Home Study on physical and mechanical properties of complex-phase conductive fiber cementitious materials
Article Open Access

Study on physical and mechanical properties of complex-phase conductive fiber cementitious materials

  • Jiuyang Li , Zhenwei Wang EMAIL logo , Jinpeng Guo , Jingwei Luo , Xinmei Fan and Yuepeng Zhu
Published/Copyright: July 20, 2024
Download Article (PDF)
Become an author with De Gruyter Brill
Submit Manuscript Author Information
REVIEWS ON ADVANCED MATERIALS SCIENCE
From the journal REVIEWS ON ADVANCED MATERIALS SCIENCE Volume 63 Issue 1

Abstract

With the continuous upgrading of infrastructure construction and the gradual development of theoretical research about engineering construction, higher performance requirements have been put forward for concrete materials. Therefore, to meet the engineering quality requirements of various concrete structures, the research direction of engineering materials has shifted towards developing new concrete with high strength, high ductility, high toughness, and other multifunctional properties. Mixing two or more types of fibers with conductive properties with the cement matrix material allows various fibers to leverage their strengths and weaknesses, thereby utilizing their respective characteristics. This results in the formation of a complex-phase conductive fiber cementitious material (CFCM), which enhances the safety, durability, and toughness of the structure. It enables the engineering structure to exhibit intelligence and resourcefulness, thereby improving its service life and reducing the full life cycle cost of the cementitious material structure. Additionally, this approach relatively eases the demand for concrete materials and reduces material consumption. This method represents one of the research directions for new concrete. Complex-phase CFCMs are essentially smart materials capable of sensing not only compressive or tensile stresses but also temperature. The emergence of CFCM represents a significant step forward in enhancing the mechanics, functionality, and sustainability of modern infrastructure. In this experiment, an orthogonal test involving 16 working conditions with three factors and four levels was designed, with steel fiber (SF) type, SF content, and carbon fiber (CF) content as the factors. The study focused on the physical and mechanical properties of composite conductive fiber cement-based materials containing both SF and CF. Performance indicators such as flexural strength, volume resistivity, and energized temperature rise of the composite conductive fiber cement-based materials were tested. The analysis of orthogonal tests produced the following results regarding the degree of influence of each factor on the mechanical and physical properties: the order of influence on flexural strength was SF doping > SF type > CF doping. Further analysis revealed that the best combination was A4B4C4. The relationship between the effect of each factor on resistivity is as follows: carbon fiber doping > SF doping > SF type. Comparing the weights between the levels, it can be observed that the optimal combination of conductivity schemes is also A3B4C4. SF and CFs, respectively, enhanced the mechanical and physical properties of complex-phase conductive fiber cementitious materials. The results of the temperature rise test on cementitious materials concluded that there is a certain relationship between the temperature rise and electrical conductivity. Specifically, the higher the electrical conductivity, the greater the temperature rise observed. Through orthogonal analysis of electrical conductivity, disregarding the effect of the non-significant influence factor SF type on the conductive heating test, the impact of two factors, CF doping and SF doping, on the heating test was investigated under 16 sets of conditions, and the data were analyzed visually. The optimal mix ratio for the test is A3B4C4, determined through comprehensive optimization of orthogonal and intuitive analyses. This means that the optimal physico-mechanical properties are achieved when using copper-plated SFs, with a SF dosage of 1.25% and a CF dosage of 0.48%. As a preceding study in the field of intelligent concrete, this experiment explores the research path of intelligent concrete, which holds positive significance for subsequent, more intricate research endeavors.

Keywords: cementitious materials; steel fibers; carbon fibers; mechanical properties; physical properties

1 Introduction

Concrete stands as a foundational building material integral to the construction of civil engineering projects, including roads, bridges, and residential structures. Its indispensable role underscores its significance in the realm of construction, forming the essential core of diverse infrastructure developments. In recent years, as society has rapidly developed and progressed, the inadequacy of traditional cementitious materials with single functional properties has become apparent. These materials struggle to meet the demands of multifunctional engineering needs and address the challenges posed by the ongoing technological revolution. The evolving landscape necessitates a reevaluation and advancement in cementitious materials to align with contemporary engineering requirements and adapt to the changing dynamics brought about by the new technological era. In contemporary times, the concept of “smart materials” has garnered widespread attention across various spheres of society. The incorporation of these “smart materials” into engineering materials, particularly concrete, imparts distinctive qualities such as self-perception, self-regulation, self-repair, and self-adaptation. This transformative integration elevates conventional concrete to the realm of “smart concrete,” reflecting advancements that align with the principles of self-awareness and adaptive functionality. Currently, numerous physical and mechanical properties of smart concrete have become a prominent research topic. This burgeoning area of study reflects the heightened interest and significance in exploring the characteristics and capabilities of smart concrete in today’s research landscape. Among these, conductive fiber concrete serves as the cornerstone of intelligent concrete. It constitutes a concrete matrix incorporating one or more “smart materials” (conductive fibers) as filler materials, resulting in the formation of conductive composite materials [1,2,3,4]. In ordinary concrete under normal conditions, the resistivity typically falls within the range of 106–109 Ω·cm. However, when incorporating “smart materials” into the mix, such as conductive concrete, the resistivity can be reduced to below 104 Ω·cm [5]. These conductive materials include steel fibers (SFs) [6,7,8], steel slag [9,10], CFs [11], carbon nanotubes [12,13], graphene [14,15], carbon black [16], and others. Conductive concrete, characterized by robust electrical conductivity, has already found application in engineering for functions related to both electrical and thermal conductivity. This versatile material serves various purposes in relevant fields, showcasing its potential for practical use [17]. With the increasing maturity of research on the mechanical properties of SF cementitious composites, there has been a gradual increase in research on their electrical and thermal properties as well. However, SFs are prone to surface corrosion and passivation in the highly alkaline environment of the cementitious matrix. This leads to a gradual decrease in the electrical conductivity of conductive cementitious composites with age. Therefore, considering the excellent strength of SFs and their good electrical conductivity, an increasing number of scholars are incorporating an appropriate amount of SFs and other conductive phases into cementitious materials. This approach allows for the preparation of composite materials that not only meet the requirements for higher strength but also ensure the stability of electrical conductivity in conductive cementitious composites. Guan et al. [18] incorporated smart concrete materials, specifically short-cut CFs, into the concrete mix. Their findings revealed an increase in tensile strength and demonstrated good sensitivity to temperature and stress. Li et al. [19,20] conducted a study on on-site snow melting, ice melting, and laboratory de-icing using CF conductive concrete panels. The study results demonstrated that the heat generated by conductive CF concrete effectively melts the snow on the road surface. As a consequence, CF concrete exhibits high temperature sensitivity. When an electric field is applied to CF concrete, it induces a thermoelectric effect, commonly referred to as the electrothermal effect, within the concrete. Hence, CF conductive concrete finds application in projects such as bridge pavements, airport runways, and plant roofs. Leveraging the electric heat effect, it achieves automatic snow melting and de-icing, offering a greener, more efficient, and feasible method. This approach aligns with China’s principles of green and sustainable development.

In the study of conductive cementitious materials, several factors need consideration, including the resistivity of the conductive material, cost, dispersion, and others. For instance, carbon nanotubes exhibit excellent electrical conductivity, mechanical strength, and thermal stability. When used as a conductive phase additive in materials, they can effectively reduce the electrical resistivity of concrete, providing more stable resistance data. However, their application in projects is constrained by cost considerations [21]. Graphite and carbon black are easily obtainable and cost-effective materials, exhibiting excellent electrical conductivity and serving as high-quality electrically conductive fillers. The particle size distribution of carbon black influences its electrical conductivity. However, excessively high graphite content in concrete may adversely impact the mechanical properties of the material [22,23]. Carbon nanotubes, carbon nanofibers, carbon black nanoparticles, and graphite all fall under the category of conductive phase materials at the carbon nanoscale, characterized by a substantial specific surface area. However, their dispersion in the concrete mixing process poses a challenge due to their nanoscale dimensions. CF possesses commendable electrical, thermal, and mechanical properties, and it is more conducive than graphite for forming a conductive network within the concrete. Consequently, CF concrete exhibits superior conductive properties compared to graphite concrete. As domestic CF production technology matures and experiences rapid growth, CF is no longer reliant on imports. This development has led to a significant reduction in the preparation costs of CF conductive concrete. SFs contribute to favorable electrical and mechanosensitive properties in concrete [6,7,24]. The incorporation of both CF and SF in concrete not only leads to a significant improvement in mechanical properties, durability, and impact resistance but also facilitates the interlacing of fibers within the concrete, forming a staggered conductive network. This arrangement further enhances electrical conductivity.

To meet the engineering specifications for conductive concrete, factors such as electrical conductivity, mechanical properties, and electro-thermal effects must be taken into account. The incorporation of conductive phase materials into cementitious materials serves to enhance the mechanical, electrical, and thermal properties of cementitious composites, all while preserving structural integrity. Conductive fiber mortar not only serves as a research foundation for cement-based materials but also functions as a material for snow and ice melting on roads. In addition to requiring mechanical strength and conductive stability, it should exhibit excellent electrical and thermal conductivity. Belli et al. [25] conducted a study wherein SFs were incorporated into mortar to investigate its physical properties and electrical conductivity. The findings revealed a notable enhancement, with the tensile and flexural strength of the mortar increasing by 100% following the inclusion of SFs. Moreover, this incorporation resulted in a reduction in the resistivity of the mortar by one order of magnitude. Reza et al. [26] discovered that the tensile strength of CF reinforced mortar, with a volumetric fraction of 0.6%, increased by approximately three times compared to normal mortar. Chiarello and Zinno [27] conducted an investigation into the electrical conductivity of CF-reinforced cement composites. They analyzed various factors influencing it, including fiber volume fraction, fiber length, hydration time, and sand–cement ratio. The results demonstrated that the addition of a small quantity of CFs to the cement mortar substantially increased the electrical conductivity of the material. In contrast, scholars such as Li and Wang [28], Ba and Gao [29], Huang et al. [30], and Chen and Chung [31] discovered that the inclusion of CFs led to a reduction in the compressive strength of cementitious materials. The phenomenon wherein conductive cementitious materials generate heat when energized is referred to as the electrothermal effect, also known as the Joule effect. Resistivity emerges as the primary factor influencing the thermal power of conductive fiber mortar composites. Under constant voltage conditions, materials with different resistivities exhibit varying heating powers.

Hence, formulating conductive mortar with excellent electrical conductivity holds great significance for its widespread application in engineering. In this study, building upon prior research, an experimental study was conducted to investigate the compounding of SF and CF on the mechanical properties, electrical conductivity, and electro-thermal effects of cement mortar. The objective is to explore the potential application of fiber conductive mortar in the snow and ice melting operations of overpasses, platforms, pavements, and other pavement structures in the cold regions of the northeast.

2 Test materials and experimental design

2.1 Test materials

The required raw materials for this test primarily include concrete matrix components (cement, sand), conductive phase materials (SFs, CFs), and admixtures (water-reducing agent, dispersant, defoamer). The cement used is ordinary silicate cement (P.O42.5) manufactured by Jilin Yatai Group Yitong Cement Co., Ltd. Its physical properties and chemical composition comply with the specifications outlined in the General Silicate Cement standard (GB175-2020) [32]. Medium sand with a fineness modulus of 2.61 is chosen as the sand component, meeting the specifications outlined in the Standard for Quality and Inspection Methods of Sand and Stone for Ordinary Concrete (JGJ 52-2006) [33]. The water-reducing agent produced by Hongxiang Building Admixture Factory in Laiyang City, Shandong Province was selected for the test. Hydroxyethyl cellulose (HEC) and tributyl phosphate (chemical molecular formula C12H27PO4) were chosen as the dispersant and defoamer, respectively, for the test.

The test utilized four types of SFs (shear, milled pin type, copper-plated type, end-hook type) produced by Hengshui Maurer Metal Products Co. Ltd, designated as SFA, SFB, SFC, and SFD, respectively, as shown in Figure 1. The basic properties are detailed in Table 1, and they conform to the standard test for Steel Fiber for Concrete (GB/T 39147-2020) [34].

Figure 1 Types of SFs. (a) SFA. (b) SFB. (c) SFC. (d) SFD.
Figure 1

Types of SFs. (a) SFA. (b) SFB. (c) SFC. (d) SFD.

Table 1

SF performance index

Performance indicators Sheared steel fiber (SFA) Milled pinned steel fiber (SFB) SF copper plated (SFC) End hooked SF (SFD)
Fiber length (mm) 38 32 13 35
Tensile strength (MPa) 450 720 2,850 1,150

The CF selected for the test, manufactured by Toray Carbon Fiber (Guangdong) Limited Liability Company, is depicted in Figure 2, and its fundamental properties are detailed in Table 2.

Figure 2 Carbon fiber.
Figure 2

Carbon fiber.

Table 2

Basic performance parameters of CF

Fiber diameter (μm) Standard length (mm) Heap density (g·cm−3) Carbon content (%) Tensile strength (MPa) Tensile modulus (GPa) Density (g·cm−3) Resistivity (Ω·cm)
7 8 0.4 97 3,530 230 1.76 1.0–1.3

2.2 Experimental design

2.2.1 Base mix for cementitious materials

In this test, cement, sand, water, and water reducer were utilized as test materials to prepare cementitious materials with a matrix water-cement ratio of 0.49. The baseline mix ratios for the cementitious material are presented in Table 3.

Table 3

Cement mortar base mix ratio

Raw materials Clinker Sand Water Water reducing agent
Dosage (kg·m−3) 450.00 627.00 176.00 0.9

2.2.2 Orthogonal experimental design

In 2012, Yuan [35] conducted a study on the piezoelectric properties of CF concrete. The best pressure-sensitive properties were achieved when the composite was externally doped with 0.5% CFs. In 2020, Wang et al. [36] conducted a study on the compressive strength, flexural strength, resistivity, and pressure-sensitive properties under monotonic loading for hybrid fiber reactive powder concrete with varying amounts of SF and CF. The results indicate that concrete with a steel fiber content of 1% and CF content of 0.5% exhibits higher mechanical strength and excellent pressure sensitivity. In order to obtain better mechanical and electrical properties, the SF and CF are selected according to the volume of doping, in which the doping of the four SFs is 0, 0.35, 0.65, 0.95, and 1.25%; CF doping is 0, 0.12, 0.24, 0.36, and 0.48%. Two types of fibers, SFs and CFs, were compounded and blended into cementitious materials to prepare complex-phase conductive fiber mortar. A three-factor, four-level orthogonal test was designed to investigate the electrical conductivity, flexural strength, and electrical and thermal properties of complex-phase conductive fiber mortar. Four different fiber dosages were designated as design levels, utilizing SF type, SF dosage, and CF dosage as the test factors. Sixteen groups (48) of standard mortar specimens, each with dimensions of 40 mm × 40 mm × 160 mm, were fabricated. The dosage of complex-phase conductive fibers is detailed in Table 4. Among them, SF and CF represent steel fibers and carbon fibers, respectively. A, B, C, and D represent four types of SFs (shear, milled pin, copper-plated, and end-hooked), and the numbers after the letters represent the volume doping of conductive fibers. For example, SFA125 represents the shear-type SF with a volume dosage of 1.25%, and CF24 represents the CF with a volume dosage of 0.24%. HEC and tributyl phosphate are used as the dispersant and antifoam agent in this test, with selected dosages of 0.4 and 0.03% of the total mass of the cementitious material, respectively.

Table 4

Complex phase conductive fiber doping and orthogonal test factor level table

Test conditions SF CF
Factor (A) Factor (B) Factor (C)
SF types Mass admixture (kg·m−3) Admixture (%) Mass admixture (kg·m−3) Admixture (%)
L-1 1 (SFA) 27.3 1 (0.35) 2.12 1 (0.12)
L-2 1 (SFA) 50.7 2 (0.65) 4.24 2 (0.24)
L-3 1 (SFA) 74.1 3 (0.95) 8.48 3 (0.36)
L-4 1 (SFA) 97.5 4 (1.25) 16.96 4 (0.48)
L-5 2 (SFB) 27.3 1 (0.35) 4.24 2 (0.24)
L-6 2 (SFB) 50.7 2 (0.65) 2.12 1 (0.12)
L-7 2 (SFB) 74.1 3 (0.95) 16.96 4 (0.48)
L-8 2 (SFB) 97.5 4 (1.25) 8.48 3 (0.36)
L-9 3 (SFC) 27.3 1 (0.35) 8.48 3 (0.36)
L-10 3 (SFC) 50.7 2 (0.65) 16.96 4 (0.48)
L-11 3 (SFC) 74.1 3 (0.95) 2.12 1 (0.12)
L-12 3 (SFC) 97.5 4 (1.25) 4.24 2 (0.24)
L-13 4 (SFD) 27.3 1 (0.35) 16.96 4 (0.48)
L-14 4 (SFD) 50.7 2 (0.65) 8.48 3 (0.36)
L-15 4 (SFD) 74.1 3 (0.95) 4.24 2 (0.24)
L-16 4 (SFD) 97.5 4 (1.25) 2.12 1 (0.12)

2.3 Test methods

2.3.1 Mechanical property tests

Since the flexural strength of SF cementitious composites is significantly higher than that of cementitious sand specimens without SFs, ordinary flexural testing machines are unable to fully fracture them. The mechanical specimens in this study all of the dimension 40 mm × 40 mm × 160 mm, and their flexural strength tests are conducted using the three-point bending loading method. Prior to the test, the load application position on the specimen was marked. Subsequently, the specimen was positioned on the flexural testing machine according to the correct placement, and the flexural strength of the cement mortar was conducted in accordance with the relevant provisions and requirements outlined in the “Polymer-modified Cement Mortar Test Procedure” (DL/T 5126-2021) [37]. The formula for flexural strength is presented in Eq. (1), and the results are accurate to 0.01 MPa.

(1) f b = 1.5 PL b 3 ,

where f b is the flexural strength (MPa), P is the destructive load (N), L is the distance between supporting cylinders (mm), and b is the side length of prismatic square section (mm).

After calculating the flexural strength value of each specimen, the average of the flexural strength values of a group of three specimens shall be taken as the test result. If there are three flexural strength values exceeding ±10% of the average value, those values should be excluded. The average value of the remaining two values will then be considered as the final test result for flexural strength. The schematic diagram of the three-point bending loading is shown in Figure 3.

Figure 3 Flexural strength test.
Figure 3

Flexural strength test.

2.3.2 Conductivity test

The voltammetric resistance can be categorized into internal and external methods. Due to the significantly higher resistance value of conductive fiber cement-based material compared to the resistance value of the voltmeter and ammeter, employing the external method with a large voltmeter shunt introduces substantial test errors. Conversely, the internal method with a small ammeter shunt minimizes test errors, resulting in highly accurate data measurements. Therefore, the internal method is preferred for measuring the resistance of conductive fiber cement-based material. The circuit diagrams for the internal and external connection methods are depicted in Figure 4.

Figure 4 Circuit diagram of internal and external connection method.
Figure 4

Circuit diagram of internal and external connection method.

For the two-electrode voltammetry measurement of resistance, the principle equation for the derivation of Ohm’s law formula, expressing the relationship between voltage, current, and resistance, is illustrated in Eq. (2).

(2) R = U I .

Based on the measured resistance values, the resistivity of the tested parts is calculated using the volume resistivity formula (3).

(3) ρ = RA L ,

where ρ is the resistivity (Ω·m), R is the resistance value (Ω), L is the electrode spacing (m), and A is the cross-sectional area (m2).

A digital multimeter served as an ammeter connected in series to the circuit to measure the current of the specimen during the test. Additionally, a current acquisition system was employed to transmit the electrical signal to the computer through a converter and record the change in the specimen current with time in real-time. The conductivity performance test is illustrated in Figure 7.

2.3.3 Warming test

To investigate the warming pattern of specimens under energized conditions for various complex-phase conductive fiber mortars, this test applied a 64 V DC voltage to the specimens. The specimens were energized continuously for 120 min, during which the entire process involved collecting current data and monitoring temperature changes. To maintain a controlled test environment and prevent heat exchange with the surroundings, a custom-made insulation box using benzene insulation boards was employed.

In this study, the warming test is conducted based on electrical conductivity. The two-electrode method is employed to integrate the test block into the circuit. Monitoring of current and voltage is achieved by connecting the current collector and signal converter in series to the circuit. Real-time current collection is performed, and the data are recorded and saved. Qin [38] conducted resistance testing on the specimen using DC voltammetry. This method requires synchronizing the voltage and current on both ends of the specimen using the same frequency voltage collector and current collector. However, ensuring the synchronicity of the two collectors in practice is challenging, and the use of two collectors also increases costs. To address this issue, an RS485 converter was employed to collect the serial port data from the collector into an RS485 serial port. This setup enables direct connection with the computer for the conversion of electrical signals into digital signals, facilitating real-time monitoring and recording of data.

The test instruments utilized include a laptop computer, DC power supply, digital multimeter, HY004 collector, and RS485 converter. The connection scheme for receiving electrical signal data during the test is illustrated in Figure 5.

Figure 5 Data reception connection method.
Figure 5

Data reception connection method.

The test was conducted with the specimen energized for the collection of temperature data. The experimental apparatus used included a laptop computer, thermocouples, and a sheet-type temperature probe. Among these instruments, the use of a sheet-type temperature probe is preferred due to its ability to closely adhere to the specimen and its higher sensitivity to temperature changes. Detailed test connections with the K-type temperature sensor are depicted in Figure 6.

Figure 6 Ramp-up test connection.
Figure 6

Ramp-up test connection.

Liu [39] compared the accuracy and dispersion of the internally buried copper sheet electrode method with the pasted electrode method for measuring the resistance value of conductive fiber concrete. The results indicated that the resistance values obtained by the embedded copper sheet electrode method were significantly larger than those obtained by the paste electrode method. Although the error values of both groups are within the normal error tolerance, the paste electrode method exhibits better stability. Therefore, in this test, the paste electrode method was selected to conduct the conductivity and temperature rise performance test of the conductive fiber cementitious material. For the test setup, copper foil conductive tape is pasted on both ends of the test piece, and a voltage of 64 V (DC power supply) is applied for 2 h. Four sheet-type temperature probes are adhered to the specimen surface at the positions shown in Figure 6. While the power supply is active, temperature data are recorded every 1 s for the temperature changes at the four positions on the specimen. The arrangement of the lamellar temperature probes and electrodes is depicted in Figure 7. Additionally, the temperature rise test process diagram and test schematic are illustrated in Figure 8.

Figure 7 Temperature probe and electrode arrangement.
Figure 7

Temperature probe and electrode arrangement.

Figure 8 Schematic diagram of the conductivity test experiment. (a) Mortar specimen electric heat test chart. (b) Schematic diagram of mortar specimen temperature sensitivity.
Figure 8

Schematic diagram of the conductivity test experiment. (a) Mortar specimen electric heat test chart. (b) Schematic diagram of mortar specimen temperature sensitivity.

2.4 Specimen preparation

Measure the necessary masses of sand, cement, water reducer, CF, SF, dispersant, defoamer (C12H27PO4), and water according to the test design requirements and the mix ratio for the mortar test block. Initially, sand and cement are mixed and stirred for 30 s. Subsequently, SFs are added sequentially, and dry mixing is continued for 60 s to achieve a uniform mixture of each aggregate. Subsequently, the prepared CF dispersion, along with water and water-reducing agent solution, was poured into the mixer and continued to mix for 180 s. Upon completing the molding process, it is necessary to subject the mold to vibration on the vibration table. Simultaneously, a plastering knife should be used to smooth the surface of the specimen until the pulp on the surface of the specimen mold floats without the presence of excessive bubbles. Subsequently, the vibration table can be turned off. The specimen surface should then be covered with plastic wrap to maintain the humidity of the specimen. Finally, after placing the specimens in a room for 24 h, they can be demolded and numbered. After demolding, the specimens are placed in a standard curing room under specified conditions for 28 days. Upon completion of the curing period, the specimens are removed and placed on an indoor surface for 6 h to allow them to dry before conducting various performance tests. The CF dispersion method and preparation flowchart are illustrated in Figures 9 and 10.

Figure 9 CF dispersion flow chart.
Figure 9

CF dispersion flow chart.

Figure 10 Flow chart for the preparation of complex phase conductive fiber cementitious materials.
Figure 10

Flow chart for the preparation of complex phase conductive fiber cementitious materials.

3 Orthogonal test design and result analysis

The three analysis methods employed in the orthogonal test are range analysis, variance analysis, and matrix analysis. Practical application demonstrates that the range analysis method can present test data in a visually intuitive and clear manner. Through simple numerical calculations, results can be assessed, enabling the determination of primary and secondary factors, optimal levels, and optimal combinations resulting from experimental optimization. Variance analysis is a mathematical method used to differentiate between the differences in experimental results caused by changes in factor levels (or interactions) and the differences caused by error fluctuations. As one of the most fundamental methods of mathematical statistics, variance analysis offers advantages such as simplicity, minimal calculation requirements, and easy dissemination. It serves as an effective tool for analyzing experimental data in scientific and production research. The above two methods are subject to varying degrees of influence from subjective factors during the analysis process. In contrast, matrix analysis is a relatively objective method for processing test data. By calculating the weight of each factor and level affecting the test results, the optimal combination scheme of the test can be determined.

3.1 Mechanical properties orthogonal test results

The research and analysis of the mechanical properties, specifically the flexural strength, of the complex-phase conductive fiber mortar primarily employed orthogonal test polar analysis, analysis of variance, and matrix analysis. This approach was utilized to investigate the impact of each factor on the flexural strength of the complex-phase conductive fiber mortar, discerning the main and secondary influences. The analysis involved a comprehensive examination of the factors and levels, considering the test indicators, and culminating in the identification of the optimal combination of factors and levels. Table 5 provides a summary of the orthogonal test results for the flexural strength of complex-phase conductive fiber mortar.

Table 5

Summary of flexural strength test results of complex-phase conductive fiber mortar

Test conditions Flexural strength (MPa) Test conditions Flexural strength (MPa) Test conditions Flexural strength (MPa) Test conditions Flexural strength (MPa)
L-1 5.02 L-5 11.38 L-9 12.11 L-13 13.38
L-2 10.57 L-6 8.13 L-10 14.74 L-14 16.55
L-3 13.47 L-7 16.02 L-11 16.92 L-15 15.11
L-4 15.48 L-8 13.63 L-12 17.73 L-16 18.20

3.1.1 Flexural strength extreme variance analysis

The results of the flexural strength under the 28-days orthogonal test of complex-phase fiber mortar are presented in Figure 11. The test outcomes were subjected to polar analysis, and the results of the analysis are detailed in Table 6. In the table, L-1 represents the test conditions, and the information regarding fiber types and dosages for each group of conditions is presented in Table 4.

Table 6

Summary of the results of the analysis of extreme variance

Parameters A (SF type) B (SF dosage) C (CF dosage) Blank column
k1 11.14 10.47 12.07 13.83
k2 12.29 12.50 13.70 13.63
k3 15.37 15.38 13.94 14.45
k4 15.81 16.26 14.90 12.71
Polar deviation R 4.67 5.79 2.84 1.74
Figure 11 Flexural strength of complex-phase conductive fiber mortar.
Figure 11

Flexural strength of complex-phase conductive fiber mortar.

Table 6 presents the polar analysis results derived from the orthogonal test data for complex-phase conductive fiber mortar. The polar differences in the effect of SF type, steel fiber dosage, and CF dosage on the 28-days flexural strength of complex-phase conductive fiber mortar were 4.67, 5.79, and 2.84, respectively. The degree of influence of different factors on the 28-days flexural strength of complex-phase conductive fiber mortar specimens is ranked as follows: SF dosage > SF type > CF dosage. According to the orthogonal test results, it is evident that the SF dosage has the most significant effect on its flexural strength.

To more clearly illustrate the impact of each factor on the flexural strength of complex-phase conductive fiber mortar specimens at different levels, a line graph depicting the average results obtained at each level is presented in Figure 12.

Figure 12 Orthogonal test factor analysis.
Figure 12

Orthogonal test factor analysis.

The influence of factor A (type of SF) on the flexural strength of mortar specimens is depicted in Figure 12. The end-hook type SFs exhibited the most significant impact on flexural strength, closely followed by copper-plated SFs. The difference in the contribution to flexural strength between these two types of SFs was merely 2.86%. The absence of coarse aggregate in the mortar specimen results in reduced friction between the SF and the matrix. However, the end-hook type SF, characterized by a specific bending angle at both ends of the hook, enhances its friction with the matrix. Regarding copper-plated fibers, the characteristic of a higher density of SFs per unit volume plays a role. Consequently, the end-hook type SF contributes the most, with the contribution values showing a closer proximity between copper-plated SFs and the end-hook type SFs. In Figure 12, the impact of factor B (SF dosage) on the flexural strength of mortar specimens is evident. The flexural strength exhibits a consistent upward trend with the increase in SF dosage. In other words, as the SF dosage increases, the flexural strength also gradually rises. The flexural strength of the mortar specimen reaches its maximum value when the SF dosage is 1.25%. This indicates that within a certain range, an increased dosage of SF corresponds to higher flexural strength in the fiber mortar specimen, establishing a positive and significant relationship between the two. From Figure 12 and Table 6, it is evident that factor C (CF dosage) has the smallest extreme difference, indicating the least impact of CF dosage on the flexural strength of the mortar specimens. With the increase in CF dosage, the flexural strength gradually increases, reaching its peak when the dosage of CF is 0.48%. The performance of CFs in concrete and mortar specimens differs, with the effect of CFs on flexural strength in mortar specimens being more pronounced. This is attributed to the absence of coarse aggregate incorporation, allowing the short-cut CFs to form a more thorough bond with the mortar specimen matrix, thereby fully leveraging their high resilience modulus.

3.1.2 Analysis of variance for flexural strength

The variance analysis method in the orthogonal test was employed to analyze the results of the flexural strength test for composite conductive fiber mortar. The analysis results are presented in Table 7.

Table 7

Summary of variance analysis results

Test name Factor Sum of squared deviations Degree of freedom Mean square f ratio P ratio
Flexural strength A (SF type) 63.25 3 21.08 10.16 0.0443
B (SF dosage) 84.93 3 28.31 13.64 0.0297
C (CF dosage) 16.64 3 5.55 2.67 0.2204
Error 6.22 3 2.07

As indicated in Table 7, there are two significant factors and one non-significant factor. The significant factors have a significance level (P) less than 0.05. Factor C (CF admixture) is a non-significant factor, with its significance level (P) greater than 0.05 [40]. Given that the P-value of factor B is lower than the P-value of factor A, it indicates that the impact of factor B (SF dosage) on flexural strength is more pronounced than the impact of factor A (SF type) on flexural strength. Factor C has the least influence on flexural strength, indicating that the contribution of CF content to flexural strength is minimal. As the dosage of SFs increases, the tensile strength of the complex phase conductive cementitious materials also increases due to the high modulus of the SFs. With higher SF content, the tensile strength increases due to enhanced fiber bridging. However, the tensile strain capacity at peak stress decreases [41,42]. It can be concluded that the results of variance analysis are in line with the findings of the range analysis.

3.1.3 Flexural strength matrix analysis

A matrix analysis was conducted on the flexural strength test results of the complex-phase conductive fiber mortar using the analytical method in the orthogonal test. The summarized results are presented in Table 8.

Table 8

Summary of matrix analysis results

Level of factors Flexural strength
Weighted calculated value Grand total
A1(SFA) 0.0716 0.3511
A2(SFB) 0.0790
A3(SFC) 0.0988
A4(SFD) 0.1017
B1(0.35%) 0.0835 0.4353
B2(0.65%) 0.0996
B3(0.95%) 0.1226
B4(1.25%) 0.1296
C1(0.12%) 0.0472 0.2136
C2(0.24%) 0.0536
C3(0.36%) 0.0545
C4(0.48%) 0.0583

According to the results of matrix analysis, the weight values of its three factors are 0.3511, 0.4353, and 0.2136, respectively. Based on the magnitude of the weight values, the order of significance of the factors can be directly derived as B > A > C. Further analysis results in the optimal combination as A4B4C4. The matrix analysis method remains unaffected by subjective factors throughout the entire evaluation cycle, ensuring the high reliability of the research results. Through range, variance, and matrix analysis, it is observed that the impact of various factors on the flexural strength of mortar test blocks is consistent. The test results have undergone the steps of analysis, verification, and re-verification, leading to greater accuracy in the findings.

3.2 Conductivity orthogonal test results

The electrical conductivity (volume resistivity) of composite conductive fiber mortar undergoes scrutiny through range analysis, variance analysis, and matrix analysis. The discussion delves into the impact of various factors on the volume resistivity of composite conductive fiber mortar. A comprehensive analysis of the influence of different factors and levels on the test index is conducted, leading to the determination of the optimal combination of factors and levels. Table 9 summarizes the orthogonal test results for the volume resistivity of composite conductive fiber mortar.

Table 9

Summary of volume resistivity test results for complex-phase conductive fiber mortar

Test conditions Volume resistivity (Ω·m) Test conditions Volume resistivity (Ω·m) Test conditions Volume resistivity (Ω·m) Test conditions Volume resistivity (Ω·m)
L-1 71.47 L-5 29.72 L-9 24.79 L-13 23.56
L-2 34.88 L-6 38.76 L-10 23.60 L-14 12.20
L-3 25.80 L-7 14.90 L-11 14.34 L-15 45.48
L-4 12.42 L-8 30.02 L-12 15.92 L-16 24.02

3.2.1 Volume resistivity polarization analysis

The results of volume resistivity under the 28-days orthogonal test of complex-phase fiber mortar are depicted in Figure 13. The test outcomes underwent characterization through polar analysis, and the analysis results are presented in Table 10.

Figure 13 Flexural strength of complex phase conductive fiber mortar.
Figure 13

Flexural strength of complex phase conductive fiber mortar.

Table 10

Summary of the results of the extreme variance analysis

Parameters A (SF type) B (SF dosage) C (CF dosage) Blank column
k1 36.14 37.39 37.15 28.62
k2 28.35 27.36 31.50 25.70
k3 19.66 25.13 23.20 25.78
k4 26.31 20.59 18.62 30.36
Polar deviation R 16.48 16.79 18.53 4.66

As observed in Table 10, the corresponding extreme values for the three factors (A, B, and C) are 21.28, 25.01, and 28.02, respectively. The relationship between the effect of each factor on resistivity is as follows: (C) CF doping > (B) SF doping > (A) SF type. The better the conductivity of the complex-phase conductive fiber mortar, the smaller its resistivity value. The optimized level combination is A3B4C4, indicating that the use of copper-plated SFs at a dosage of 1.25% and CFs at a dosage of 0.48% has the most significant impact on reducing mortar resistivity, resulting in the highest degree of resistivity reduction and the best electrical conductivity.

To better illustrate the influence of each factor on the volume resistivity of the mortar test block at different levels, an effect line chart has been created to represent the average value of the results obtained at each level, as depicted in Figure 14.

Figure 14 Orthogonal test factor analysis.
Figure 14

Orthogonal test factor analysis.

As observed in Figure 14, each type of SF has a varying impact on resistivity, with copper-plated (SFC) concrete exhibiting the lowest resistivity and superior electrical conductivity. The rationale behind this observation is that the copper-plated SF has a shorter and finer length, resulting in a higher number of fibers per unit volume, facilitating interlacing between the fibers. As seen in Figure 14, the resistivity tends to decrease with the increase in SF and CF doping. The resistivity was lower when SF doping was 1.25%, showing a decrease of 44.93% relative to the doping level of 0.35%. Similarly, when CF doping was 0.48%, the resistivity decreased by 50.12% relative to the doping of 0.12%. The reason for this is that with increased doping of conductive phases, the structure of the conductive backbone improves, leading to enhanced electrical properties in both optimal and ideal scenarios.

3.2.2 Analysis of variance

The variance analysis method of orthogonal test was employed to analyze the variance of the volume resistivity test results of the composite conductive fiber mortar. The analysis results are presented in Table 11.

Table 11

Summary of variance analysis results

Test name Factor Sum of squared deviations Degree of freedom Mean square f ratio P ratio
Volume resistivity A (SF type) 552.61 3 184.20 8.86 0.0531
B (SF dosage) 604.09 3 201.36 9.69 0.0472
C (CF dosage) 825.25 3 275.08 13.24 0.0309
Error 62.34 3 20.78

It can be observed from Table 11 that the significance levels (P) of factor B and factor C are 0.0472 and 0.0309, respectively, both of which are less than 0.05, indicating that both are significant factors. Among them, CF content (C) is a highly significant influencing factor, while SF type (B) is not a significant influencing factor. It is evident that the results of this analysis align with the findings of the range analysis.

3.2.3 Matrix analysis

Matrix analysis was conducted on the volume resistivity test results of the complex-phase conductive fiber mortar using the analytical method in the orthogonal test, and the results are summarized in Table 12.

Table 12

Summary of results of matrix analysis

Level of factors Flexural strength
Weighted calculated value Grand total
A1(SFA) 0.0580 0.3181
A2(SFB) 0.0739
A3(SFC) 0.1065
A4(SFD) 0.0797
B1(0.35%) 0.0571 0.3241
B2(0.65%) 0.0781
B3(0.95%) 0.0850
B4(1.25%) 0.1038
C1(0.12%) 0.0619 0.3577
C2(0.24%) 0.0730
C3(0.36%) 0.0992
C4(0.48%) 0.1235

From Table 12, it can be observed that the sum of the weight values for the three factors (A, B, and C) is 0.3181, 0.3241, and 0.3577, respectively. It can be concluded that the factors affecting the electrical resistivity of the complex-phase conductive fiber mortar are, in descending order, C > B > A. Among the four levels of SF type (A), A3 has the highest influence weight; among the four levels of SF doping (B), B4 has the highest influence weight; and among the four levels of CF doping (C), C4 has the highest influence weight. Comparing the weights between the levels, it can be seen that the optimal combination scheme is A3B4C4, which means copper-plated SF, with a SF content of 0.125%, and a CF content of 0.48% should be added. Through matrix analysis, the above range and variance analysis are further verified, and the conclusions of the three analysis methods are consistent with each other.

3.3 Conductive fiber mortar temperature rise test study

3.3.1 Analysis of the amount of change in temperature of conductive fiber mortar at elevated temperatures

In the heating test of complex-phase conductive fiber mortar, the temperature data from four measurement points (T1, T2, T3, and T4) were averaged to obtain the maximum values, minimum values, and the differences, as shown in Table 13.

Table 13

Temperature rise of complex phase conductive fiber mortar

Test conditions Temperature initial value (°C) Temperature final value (°C) Temperature difference (°C)
L-1 28.75 32.55 3.80
L-2 24.35 30.75 6.40
L-3 29.30 41.15 11.85
L-4 28.83 57.63 28.80
L-5 30.10 35.38 5.28
L-6 30.08 34.33 4.25
L-7 28.05 49.40 21.35
L-8 31.48 51.70 20.23
L-9 27.45 36.13 8.68
L-10 30.03 46.38 16.35
L-11 25.90 32.63 6.73
L-12 27.60 35.00 7.40
L-13 27.30 41.38 14.08
L-14 30.13 40.55 10.43
L-15 27.95 35.10 7.15
L-16 28.05 34.83 6.78

3.3.2 Conductive fiber mortar temperature rise test analysis

Zhou [43] discovered that under the same voltage, the conductivity of the test specimen is enhanced, resulting in lower resistance. Consequently, the heating power of the test specimen increases, leading to a greater amount of temperature change. The temperature rise test exhibits a certain correlation with conductivity; the higher the conductivity, the greater the temperature rise. In this study, orthogonal analysis of electrical conductivity reveals that the order of influence of the three factors on electrical conductivity is as follows: (C) CF content > (B) SF content > (A) SF type. The SF type factor has the lowest influence and is the least significant factor. Therefore, the influence of the SF type factor is ignored, and only two factors, CF doping and SF doping, are considered for visual analysis of the data from the 16 sets of temperature rise tests under working conditions. Utilizing the data from Table 13, we can draw intuitive bar graphs to analyze the temperature difference in the complex-phase conductive fiber mortar. The following figures provide a visual analysis of the temperature difference during the warming process of the complex-phase conductive fiber mortar, as shown in Figures 15 and 16.

Figure 15 Effect of CF doping on warming test.
Figure 15

Effect of CF doping on warming test.

Figure 16 Effect of SF dosage on warming test.
Figure 16

Effect of SF dosage on warming test.

Figure 15 illustrates the impact of CF doping on the temperature rise test. It is evident that, with a constant SF doping level, the temperature difference during the heating process increases with higher CF doping levels, indicating a proportional increase in temperature rise. The maximum temperature difference in the warming test is achieved when SF doping is at 1.25% and CF doping is at 0.48%, signifying an optimal combination for the highest temperature rise during the test. Figure 16 illustrates the impact of SF dosage on the temperature rise test. It is evident that, with a constant CF dosage, the temperature difference gradually increases as the SF dosage increases. After comparing Figure 15 with Figure 16, it is found that the magnitude of change is more pronounced with the increase in CF doping when the SF doping is constant. Conversely, when the CF doping is constant, with the gradual increase in SF doping, the magnitude of change is relatively flat. The reason is that the conductivity of CF is greater than that of SF. With the incorporation of CF, the conductivity is greatly improved, leading to a noticeable change in temperature rise.

3.4 Conductive mortar current change rate

To investigate the relationship between the rate of current change and the change in temperature rise of the composite conductive fiber mortar, a data analysis was conducted on the obtained test data. The average temperature data obtained from the four temperature sensors were utilized. The data for the rate of current change and the change in temperature rise were selected at the 2 min time point to create the relevant line chart. The analysis of the above test leads to the conclusion that the conductivity and temperature rise performance of Case 4 are optimal. Figure 17 illustrates the relationship between the rate of current change, temperature, and time for Case 4.

Figure 17 The change curve of current change rate and temperature with time.
Figure 17

The change curve of current change rate and temperature with time.

The red curve in Figure 17 represents the results of the heating test of the composite fiber conductive paste test block in continuous power mode for 120 min. Due to the 48 mortar specimens subjected to a 2 h warming test for each power condition, the average values were taken for each condition from three mortar specimens. Due to the varying sensitivity of the test instrument, slight differences in the initial temperature of individual mortar specimens were observed, all falling within the error range. As seen from the figure, the heating curve of the complex fiber mortar specimen can be divided into two stages. The first stage of heating is faster, mainly evidenced by a larger temperature increase within the same energization time. In the second stage, the temperature rise gradually slowed down, and the curve approached a plateau, resulting in a relatively stable temperature. This is because at a constant temperature, the applied electric power is equal to the rate of heat exchange between the specimen and the environment, reaching a state of thermal equilibrium.

Figure 17 shows the red and blue curves representing the results of the conductive mortar electro-thermal performance test, illustrating the relationship between the rate of change of current and the amount of change in warming temperature. From the figure, it can be observed that the relationship between the rate of change of current and temperature can be divided into two stages. In the first stage, the complex-phase conductive fiber mortar exhibits a decreasing trend in current with the increase in temperature. Given that the voltage is constant, it can be inferred that the resistivity of the complex-phase conductive fiber mortar gradually increases with the rise in temperature. The phenomenon of resistivity increasing with temperature is referred to as the positive temperature coefficient (PTC) effect. Under specific conditions, the resistivity of all specimens increases within 30 min, a phenomenon known as the PTC effect [44]. At higher voltages, the PTC effect dominates in all specimens, while at lower input voltages, the negative temperature coefficient (NTC) effect dominates [45]. Both the PTC effect and the NTC effect are attributed to thermal expansion, as reported by Luo et al. [46]. It can be inferred from this that, since a 64 V DC voltage is used in this work, under energized conditions, for a very short period of time, first, thermal expansion causes the NTC effect. Subsequently, thermal expansion quickly reaches a certain level, and then the PTC effect occurs. In other words, the PTC effect begins when a high enough degree of thermal expansion is reached [45]. It is only because of the extremely short time to reach sufficient expansion that the PTC effect dominates in this test at the applied voltage. In the second stage of the phenomenon, the current curve and temperature curve of the complex-phase conductive fiber mortar show a gradual smoothing trend. This is due to the fact that the internal circuit that can be connected is basically in a stable state, and the resistivity is no longer decreasing.

As mentioned earlier, when the degree of thermal expansion is below a certain level, the NTC effect occurs due to the lapping of CF and SF and their close proximity to each other. In contrast, when the thermal expansion of the complex-phase conductive fiber material exceeds a certain value, discontinuities between the CFs occur, leading to the occurrence of PTC. It was found that the coefficient of thermal expansion of cement paste is higher [47,48]. CF is known to have a lower coefficient of thermal expansion than cement mortar and SF. When CF is subjected to temperature, its elongation is more stable than that of other materials, and the smaller coefficient of thermal expansion makes it more suitable for environments at both room and elevated temperatures. Hence, CFs exhibit commendable dimensional stability in cementitious materials, even under the demanding conditions of high temperatures. Contrarily, cement paste and SFs are susceptible to the thermal expansion associated with high temperatures. In the case of complex-phase conductive fiber mortar, where the degree of thermal expansion is higher, the discrepancy in expansion coefficients among cement paste, SFs, and CFs can result in discontinuities between the fibers. As the temperature rises, the resistance gradually decreases, manifesting a distinct PTC effect.

4 Conclusion

In this study, the impact of resistivity and flexural strength in complex-phase conductive fiber mortar was investigated through an orthogonal test. A 64 V DC voltage was applied to the electrodes of the conductive fiber mortar, and the continuous recording of specimen temperature during a 2 h energization period was conducted. Warming curves were plotted to examine the current variations throughout the warming process. Simultaneously, the influence of different combinations of fiber types and dosages on the temperature changes over time during mortar warming was also explored. Finally, the electrothermal properties of the complex-phase conductive fiber mortar were investigated in terms of the relationship between temperature and the rate of change of current. The following main conclusions were drawn:

  1. Based on the results of the orthogonal test on electrical conductivity and mechanical properties, a comprehensive analysis of the significance of each factor was conducted. The optimal combination was identified as A3B4C4, indicating that doping copper-plated SFs at 1.25% and CFs at 0.48% has a positive impact on the electrical conductivity, mechanical properties, and electrothermal properties of the composite conductive fiber mortar.

  2. At a constant voltage, increased fiber doping results in enhanced specimen conductivity, reduced volume resistivity, increased heating power, and a greater temperature change.

  3. The heating curve of the complex fiber mortar specimen can be divided into two stages. The first stage exhibits a faster rate of heating, primarily characterized by a notable increase in temperature within the same energized duration. The second stage involves a gradual slowdown in the heating process, and the curve approaches a plateau, indicating a more stable temperature under continuous energization.

  4. The relationship between the rate of change of current and temperature can be divided into two phases. In the first phase, the current of the complex-phase conductive fiber mortar tends to diminish as the temperature increases, exhibiting a PTC effect. At higher voltages, the PTC effect dominates in all mortar specimens. In the second phase of the phenomenon, both the current curve and temperature curve of the complex-phase conductive fiber mortar exhibit a gradual flattening trend. This is attributed to the fact that the internal circuit, which can be connected, has essentially stabilized, and the resistivity is no longer decreasing.

Acknowledgments

First of all, I thank teacher Li Jiuyang for determining the research direction for me and guiding my experiment. Thanks to Guo Jinpeng, Luo Jingwei, Fan Xinmei and Zhu Yuepeng for helping me complete the experiment. Thank you for your help and support.

  1. Funding information: This project is financially supported by the Science and Technology Development Plan of Jilin Province (20210203178SF) and (YDZJ202302CXJD052).

  2. Author contributions: Teacher Li Jiuyang determined the research direction and the guidance of the experiment. Wang Zhenwei, designed the experiment and wrote the thesis. Guo Jinpeng, Luo Jingwei, Fan Xinmei, and Zhu Yuepeng, provided help to complete the experiment together. All authors have accepted responsibility for the entire content of this manuscript and approved its submission.

  3. Conflict of interest: The authors state no conflict of interest.

References

[1] Chung, D. D. L. Self-heating structural materials. Smart Materials and Structures, Vol. 13, No. 3, 2004, pp. 562–565.10.1088/0964-1726/13/3/015Search in Google Scholar

[2] Li, H., Q. Zhang, and H. Xiao. Self-deicing road system with a CNFP high-efficiency thermal source and MWCNT/cement-based high-thermal conductive composites. Cold Regions Science and Technology, Vol. 86, 2013, pp. 22–35.10.1016/j.coldregions.2012.10.007Search in Google Scholar

[3] Tuan, C. Y. and S. Yehia. Evaluation of electrically conductive concrete containing carbon products for deicing. Materials Journal, Vol. 101, No. 4, 2004, pp. 287–293.10.14359/13362Search in Google Scholar

[4] Tuan, C. Y. Conductive concrete for bridge deck deicing and anti-icing. Technical Report, Nebraska Department of Road, No. SPR-PL-1(037); 2004.Search in Google Scholar

[5] Ding, S., S. Dong, A. Ashour, and B. Han. Development of sensing concrete: Principles, properties and its applications. Journal of Applied Physics, Vol. 126, No. 24, 2019.10.1063/1.5128242Search in Google Scholar

[6] Fan, L., W. Meng, L. Teng, and K. H. Khayat. Effect of steel fibers with galvanized coatings on corrosion of steel bars embedded in UHPC. Composites Part B: Engineering, Vol. 177, 2019, id. 107445.10.1016/j.compositesb.2019.107445Search in Google Scholar

[7] Demircilioglu, E., E. Teomete, and O. E. Ozbulut. Strain sensitivity of steel-fiber-reinforced industrial smart concrete. Journal of Intelligent Material Systems and Structures, Vol. 31, No. 1, 2020, pp. 127–136.10.1177/1045389X19888722Search in Google Scholar

[8] Tuan, C. Y. Electrical resistance heating of conductive concrete containing steel fibers and shavings. Materials Journal, Vol. 101, No. 1, 2004, pp. 65–71.10.14359/12989Search in Google Scholar

[9] Santillán, N., S. Speranza, J. M. Torrents, and I. Segura. Evaluation of conductive concrete made with steel slag aggregates. Construction and Building Materials, Vol. 360, 2022, id. 129515.10.1016/j.conbuildmat.2022.129515Search in Google Scholar

[10] Ding, Y., Y. Yang, R. Liu, T. Xiao, and J. Tian. Study on pressure sensitivity of smart polymer concrete based on steel slag. Measurement, Vol. 140, 2019, pp. 14–21.10.1016/j.measurement.2019.03.040Search in Google Scholar

[11] Vaidya, S. and E. N. Allouche. Strain sensing of carbon fiber reinforced geopolymer concrete. Materials and Structures, Vol. 44, No. 8, 2011, pp. 1467–1475.10.1617/s11527-011-9711-3Search in Google Scholar

[12] Wang, Y. Y. and L. Q. Zhang. Development of self-sensing cementitious composite incorporating hybrid graphene nanoplates and carbon nanotubes for structural health monitoring. Sensors and Actuators A: Physical, Vol. 336, 2022, id. 113367.10.1016/j.sna.2022.113367Search in Google Scholar

[13] Luo, B. and J. Dong. Optimizing piezoresistivity of alkaliactivated mortar using carboxylated multi-walled carbon nanotubes/basalt fibers. Materials Letters, Vol. 329, 2022, id. 133151.10.1016/j.matlet.2022.133151Search in Google Scholar

[14] Song, F., Q. Chen, Z. Jiang, X. Zhu, B. Li, B. He, et al. Piezoresistive properties of ultra-high-performance fiber-reinforced concrete incorporating few-layer graphene. Construction and Building Materials, Vol. 305, 2021, id. 124362.10.1016/j.conbuildmat.2021.124362Search in Google Scholar

[15] Lu, D., D. Wang, and J. Zhong. Highly conductive and sensitive piezoresistive cement mortar with graphene coated aggregates and carbon fiber. Cement and Concrete Composites, Vol. 134, 2022, id. 104731.10.1016/j.cemconcomp.2022.104731Search in Google Scholar

[16] Liu, L., J. Xu, T. Yin, Y. Wang, and H. Chu. Improving electrical and piezoresistive properties of cement-based composites by combined addition of nano carbon black and nickel nanofiber. Journal of Building Engineering, Vol. 51, 2022, id. 104312.10.1016/j.jobe.2022.104312Search in Google Scholar

[17] Liang, J. and Q. Yang. Prediction of over-permeability threshold of conductive polymer composites. Journal of South China University of Technology (Natural Science Edition), Vol. 8, 2007, pp. 80–82 + 88.Search in Google Scholar

[18] Guan, X., J. Ou, B. Han, M. Zhao, L. Wang, F. Zhang, et al. Research and progress of carbon fiber mechanosensitive concrete materials. Journal of Harbin Architecture University, Vol. 6, 2002, pp. 55–59.Search in Google Scholar

[19] Tang, Z., Z. Li, Z. Hou, X. Wang, Y. Liu, M. Chen, et al. Analysis of snow and ice melting mechanism of conductive concrete. Concrete, Vol. 7, 2001, pp. 8–11.Search in Google Scholar

[20] Sun, M., Z. Li, and Q. Mao. Research on the electro-thermal characteristics of CFRC. Journal of Wuhan University of Technology, Vol. 2, 1997, pp. 72–74 + 77.18.Search in Google Scholar

[21] Zhu, S. and D. D. L. Chung. Numerical assessment of the methods of measurement of the electrical resistance in carbon fiber reinforced cement. Smart Materials and Structures, Vol. 16, No. 4, 2007, pp. 1164–1170.10.1088/0964-1726/16/4/026Search in Google Scholar

[22] Kim, H. K., I. W. Nam, and H. K. Lee. Enhanced effect of carbon nanotube on mechanical and electrical properties of cement composites by incorporation of silica fume. Composite Structures, Vol. 107, 2014, pp. 60–69.10.1016/j.compstruct.2013.07.042Search in Google Scholar

[23] Nam, I. W., H. K. Kim, and H. K. Lee. Influence of silica fume additions on electromagnetic interference shielding effectiveness of multi-walled carbon nanotube/cement composites. Construction and Building Materials, Vol. 30, 2012, pp. 480–487.10.1016/j.conbuildmat.2011.11.025Search in Google Scholar

[24] Zhou, T., Y. Sun, and Y. Peng. Piezoresistive response of mechanically sensitive concrete composites with compounded functional fillers. Journal of Materials Science and Engineering, Vol. 39, No. 5, 2021, pp. 763–767.Search in Google Scholar

[25] Belli, A., A. Mobili, T. Bellezze, and F. Tittarelli. Commercial and recycled carbon/steel fibers for fiber-reinforced cement mortars with high electrical conductivity. Cement and Concrete Composites, Vol. 109, 2020, id. 103569.10.1016/j.cemconcomp.2020.103569Search in Google Scholar

[26] Reza, F., J. A. Yamamuro, and G. B. Batson. Electrical resistance change in compact tension specimens of carbon fiber cement composites. Cement and Concrete Composites, Vol. 26, No. 7, 2004, pp. 873–881.10.1016/j.cemconcomp.2003.06.002Search in Google Scholar

[27] Chiarello, M. and R. Zinno. Electrical conductivity of self-monitoring CFRC. Cement and Concrete Composites, Vol. 27, No. 4, 2005, pp. 463–469.10.1016/j.cemconcomp.2004.09.001Search in Google Scholar

[28] Li, G.-Y. and P.-M. Wang. Mechanical properties and microstructure of carbon nanotube-cementitious composites. Journal of Silicates, Vol. 1, 2005, pp. 105–108.Search in Google Scholar

[29] Ba, H. and X. Gao. Research on early cracking control measures of high performance concrete. Journal of Harbin Architecture University, Vol. 5, 2002, pp. 77–80.Search in Google Scholar

[30] Huang, L., Z. Li, and X. Song. Study on the durability of carbon fiber concrete under repeated temperature changes. Concrete, Vol. 12, 2002, pp. 35–37.Search in Google Scholar

[31] Chen, P. and D. D. L. Chung. Low-drying-shrinkage concrete containing carbon fibers. Composites Part B: Engineering, Vol. 27, No. 3, 1996, pp. 269–274.10.1016/1359-8368(95)00020-8Search in Google Scholar

[32] GB 175-2007, General purpose silicate cement.Search in Google Scholar

[33] JGJ 52-2006, Standard for quality and test methods of sand and gravel for ordinary concrete.Search in Google Scholar

[34] GB/T 39147-2020, Steel fibers for concrete.Search in Google Scholar

[35] Yuan, L. Experimental study on force electrical properties of carbon fiber smart concrete, Doctoral dissertation, Zhengzhou University, Zhengzhou, China, 2012.Search in Google Scholar

[36] Wang, L., H. Du, and X. Liu. Effect of mixed fibers on the pressure-sensitive properties of activated powder concrete. Concrete, Vol. 1, 2021, pp. 66–69.Search in Google Scholar

[37] DL/T 5126-2001, Test procedure for polymer modified cement mortar.Search in Google Scholar

[38] Qin, R. Research on the conductive, pressure-sensitive and electrothermal properties of multi-scale carbon-based cement composites, Doctoral dissertation, Harbin Institute of Technology, Harbin, China, 2014.Search in Google Scholar

[39] Liu, Z. Research on mechanical, electrical and pressure-sensitive properties of complex-phase conductive fiber concrete, China University of Mining and Technology, Xuzhou, 2022.Search in Google Scholar

[40] Abdellatief, M., W. E. Elemam, H. Alanazi, and A. M. Tahwia. Production and optimization of sustainable cement brick incorporating clay brick wastes using response surface method. Ceramics International, Vol. 49, No. 6, 2023, pp. 9395–9411.10.1016/j.ceramint.2022.11.144Search in Google Scholar

[41] Abdellatief, M., M. A. Elrahman, G. Elgendy, G. Bassioni, and A. M. Tahwia. Response surface methodology-based modelling and optimization of sustainable UHPC containing ultrafine fly ash and metakaolin. Construction and Building Materials, Vol. 388, 2023, id. 131696.10.1016/j.conbuildmat.2023.131696Search in Google Scholar

[42] Tahwia, A. M., A. M. Heniegal, M. Abdellatief, B. A. Tayeh, and M. A. Elrahman. Properties of ultra-high performance geopolymer concrete incorporating recycled waste glass. Case Studies in Construction Materials, Vol. 17, 2022, id. e01393.10.1016/j.cscm.2022.e01393Search in Google Scholar

[43] Zhou, T. Research on mechanosensitivity of cementitious materials with compounded functional fillers, Jiangsu University, Zhenjiang, 2020.Search in Google Scholar

[44] He, X. J., J. H. Du, Z. Ying, H. M. Cheng, and X. J. He. Positive temperature coefficient effect in multiwalled carbon nanotube/high-density polyethylene composites. Applied Physics Letters, Vol. 86, No. 6, 2005, id. 062112.10.1063/1.1863452Search in Google Scholar

[45] Kim, G. M., F. Naeem, H. K. Kim, and H. K. Lee. Heating and heat-dependent mechanical characteristics of CNT-embedded cementitious composites. Composite Structures, Vol. 136, 2016, pp. 162–170.10.1016/j.compstruct.2015.10.010Search in Google Scholar

[46] Luo, Y., G. Wang, B. Zhang, and Z. Zhang. The influence of crystalline and aggregate structure on PTC characteristic of conductive polyethylene/carbon black composite. European Polymer Journal, Vol. 34, No. 8, 1998, pp. 1221–1227.10.1016/S0014-3057(98)00099-8Search in Google Scholar

[47] Meng, F., X. Zhang, R. Li, J. Zhao, X. Xuan, X. Wang, et al. Electro‐induced mechanical and thermal responses of carbon nanotube fibers. Advanced Materials, Vol. 26, No. 16, 2014, pp. 2480–2485.10.1002/adma.201305123Search in Google Scholar PubMed

[48] Sellevold, E. J. and Ø. Bjøntegaard. Coefficient of thermal expansion of cement paste and concrete: Mechanisms of moisture interaction. Materials and Structures, Vol. 39, 2006, pp. 809–815.10.1617/s11527-006-9086-zSearch in Google Scholar
Received: 2024-01-29
Revised: 2024-03-25
Accepted: 2024-06-05
Published Online: 2024-07-20

© 2024 the author(s), published by De Gruyter

This work is licensed under the Creative Commons Attribution 4.0 International License.

Articles in the same Issue

  1. Review Articles
  2. Effect of superplasticizer in geopolymer and alkali-activated cement mortar/concrete: A review
  3. Experimenting the influence of corncob ash on the mechanical strength of slag-based geopolymer concrete
  4. Powder metallurgy processing of high entropy alloys: Bibliometric analysis and systematic review
  5. Exploring the potential of agricultural waste as an additive in ultra-high-performance concrete for sustainable construction: A comprehensive review
  6. A review on partial substitution of nanosilica in concrete
  7. Foam concrete for lightweight construction applications: A comprehensive review of the research development and material characteristics
  8. Modification of PEEK for implants: Strategies to improve mechanical, antibacterial, and osteogenic properties
  9. Interfacing the IoT in composite manufacturing: An overview
  10. Advances in processing and ablation properties of carbon fiber reinforced ultra-high temperature ceramic composites
  11. Advancing auxetic materials: Emerging development and innovative applications
  12. Revolutionizing energy harvesting: A comprehensive review of thermoelectric devices
  13. Exploring polyetheretherketone in dental implants and abutments: A focus on biomechanics and finite element methods
  14. Smart technologies and textiles and their potential use and application in the care and support of elderly individuals: A systematic review
  15. Reinforcement mechanisms and current research status of silicon carbide whisker-reinforced composites: A comprehensive review
  16. Innovative eco-friendly bio-composites: A comprehensive review of the fabrication, characterization, and applications
  17. Review on geopolymer concrete incorporating Alccofine-1203
  18. Advancements in surface treatments for aluminum alloys in sports equipment
  19. Ionic liquid-modified carbon-based fillers and their polymer composites – A Raman spectroscopy analysis
  20. Emerging boron nitride nanosheets: A review on synthesis, corrosion resistance coatings, and their impacts on the environment and health
  21. Mechanism, models, and influence of heterogeneous factors of the microarc oxidation process: A comprehensive review
  22. Synthesizing sustainable construction paradigms: A comprehensive review and bibliometric analysis of granite waste powder utilization and moisture correction in concrete
  23. 10.1515/rams-2025-0086
  24. Research Articles
  25. Coverage and reliability improvement of copper metallization layer in through hole at BGA area during load board manufacture
  26. Study on dynamic response of cushion layer-reinforced concrete slab under rockfall impact based on smoothed particle hydrodynamics and finite-element method coupling
  27. Study on the mechanical properties and microstructure of recycled brick aggregate concrete with waste fiber
  28. Multiscale characterization of the UV aging resistance and mechanism of light stabilizer-modified asphalt
  29. Characterization of sandwich materials – Nomex-Aramid carbon fiber performances under mechanical loadings: Nonlinear FE and convergence studies
  30. Effect of grain boundary segregation and oxygen vacancy annihilation on aging resistance of cobalt oxide-doped 3Y-TZP ceramics for biomedical applications
  31. Mechanical damage mechanism investigation on CFRP strengthened recycled red brick concrete
  32. Finite element analysis of deterioration of axial compression behavior of corroded steel-reinforced concrete middle-length columns
  33. Grinding force model for ultrasonic assisted grinding of γ-TiAl intermetallic compounds and experimental validation
  34. Enhancement of hardness and wear strength of pure Cu and Cu–TiO2 composites via a friction stir process while maintaining electrical resistivity
  35. Effect of sand–precursor ratio on mechanical properties and durability of geopolymer mortar with manufactured sand
  36. Research on the strength prediction for pervious concrete based on design porosity and water-to-cement ratio
  37. Development of a new damping ratio prediction model for recycled aggregate concrete: Incorporating modified admixtures and carbonation effects
  38. Exploring the viability of AI-aided genetic algorithms in estimating the crack repair rate of self-healing concrete
  39. Modification of methacrylate bone cement with eugenol – A new material with antibacterial properties
  40. Numerical investigations on constitutive model parameters of HRB400 and HTRB600 steel bars based on tensile and fatigue tests
  41. Research progress on Fe3+-activated near-infrared phosphor
  42. Discrete element simulation study on effects of grain preferred orientation on micro-cracking and macro-mechanical behavior of crystalline rocks
  43. Ultrasonic resonance evaluation method for deep interfacial debonding defects of multilayer adhesive bonded materials
  44. Effect of impurity components in titanium gypsum on the setting time and mechanical properties of gypsum-slag cementitious materials
  45. Bending energy absorption performance of composite fender piles with different winding angles
  46. Theoretical study of the effect of orientations and fibre volume on the thermal insulation capability of reinforced polymer composites
  47. Synthesis and characterization of a novel ternary magnetic composite for the enhanced adsorption capacity to remove organic dyes
  48. Couple effects of multi-impact damage and CAI capability on NCF composites
  49. Mechanical testing and engineering applicability analysis of SAP concrete used in buffer layer design for tunnels in active fault zones
  50. Investigating the rheological characteristics of alkali-activated concrete using contemporary artificial intelligence approaches
  51. Integrating micro- and nanowaste glass with waste foundry sand in ultra-high-performance concrete to enhance material performance and sustainability
  52. Effect of water immersion on shear strength of epoxy adhesive filled with graphene nanoplatelets
  53. Impact of carbon content on the phase structure and mechanical properties of TiBCN coatings via direct current magnetron sputtering
  54. Investigating the anti-aging properties of asphalt modified with polyphosphoric acid and tire pyrolysis oil
  55. Biomedical and therapeutic potential of marine-derived Pseudomonas sp. strain AHG22 exopolysaccharide: A novel bioactive microbial metabolite
  56. Effect of basalt fiber length on the behavior of natural hydraulic lime-based mortars
  57. Optimizing the performance of TPCB/SCA composite-modified asphalt using improved response surface methodology
  58. Compressive strength of waste-derived cementitious composites using machine learning
  59. Melting phenomenon of thermally stratified MHD Powell–Eyring nanofluid with variable porosity past a stretching Riga plate
  60. Development and characterization of a coaxial strain-sensing cable integrated steel strand for wide-range stress monitoring
  61. Compressive and tensile strength estimation of sustainable geopolymer concrete using contemporary boosting ensemble techniques
  62. Customized 3D printed porous titanium scaffolds with nanotubes loading antibacterial drugs for bone tissue engineering
  63. Facile design of PTFE-kaolin-based ternary nanocomposite as a hydrophobic and high corrosion-barrier coating
  64. Effects of C and heat treatment on microstructure, mechanical, and tribo-corrosion properties of VAlTiMoSi high-entropy alloy coating
  65. Study on the damage mechanism and evolution model of preloaded sandstone subjected to freezing–thawing action based on the NMR technology
  66. Promoting low carbon construction using alkali-activated materials: A modeling study for strength prediction and feature interaction
  67. Entropy generation analysis of MHD convection flow of hybrid nanofluid in a wavy enclosure with heat generation and thermal radiation
  68. Friction stir welding of dissimilar Al–Mg alloys for aerospace applications: Prospects and future potential
  69. Fe nanoparticle-functionalized ordered mesoporous carbon with tailored mesostructures and their applications in magnetic removal of Ag(i)
  70. Study on physical and mechanical properties of complex-phase conductive fiber cementitious materials
  71. Evaluating the strength loss and the effectiveness of glass and eggshell powder for cement mortar under acidic conditions
  72. Effect of fly ash on properties and hydration of calcium sulphoaluminate cement-based materials with high water content
  73. Analyzing the efficacy of waste marble and glass powder for the compressive strength of self-compacting concrete using machine learning strategies
  74. Experimental study on municipal solid waste incineration ash micro-powder as concrete admixture
  75. Parameter optimization for ultrasonic-assisted grinding of γ-TiAl intermetallics: A gray relational analysis approach with surface integrity evaluation
  76. Producing sustainable binding materials using marble waste blended with fly ash and rice husk ash for building materials
  77. Effect of steam curing system on compressive strength of recycled aggregate concrete
  78. A sawtooth constitutive model describing strain hardening and multiple cracking of ECC under uniaxial tension
  79. Predicting mechanical properties of sustainable green concrete using novel machine learning: Stacking and gene expression programming
  80. Toward sustainability: Integrating experimental study and data-driven modeling for eco-friendly paver blocks containing plastic waste
  81. A numerical analysis of the rotational flow of a hybrid nanofluid past a unidirectional extending surface with velocity and thermal slip conditions
  82. A magnetohydrodynamic flow of a water-based hybrid nanofluid past a convectively heated rotating disk surface: A passive control of nanoparticles
  83. Prediction of flexural strength of concrete with eggshell and glass powders: Advanced cutting-edge approach for sustainable materials
  84. Efficacy of sustainable cementitious materials on concrete porosity for enhancing the durability of building materials
  85. Phase and microstructural characterization of swat soapstone (Mg3Si4O10(OH)2)
  86. Effect of waste crab shell powder on matrix asphalt
  87. Improving effect and mechanism on service performance of asphalt binder modified by PW polymer
  88. Influence of pH on the synthesis of carbon spheres and the application of carbon sphere-based solid catalysts in esterification
  89. Experimenting the compressive performance of low-carbon alkali-activated materials using advanced modeling techniques
  90. Thermogravimetric (TG/DTG) characterization of cold-pressed oil blends and Saccharomyces cerevisiae-based microcapsules obtained with them
  91. Investigation of temperature effect on thermo-mechanical property of carbon fiber/PEEK composites
  92. Computational approaches for structural analysis of wood specimens
  93. Integrated structure–function design of 3D-printed porous polydimethylsiloxane for superhydrophobic engineering
  94. Exploring the impact of seashell powder and nano-silica on ultra-high-performance self-curing concrete: Insights into mechanical strength, durability, and high-temperature resilience
  95. Axial compression damage constitutive model and damage characteristics of fly ash/silica fume modified magnesium phosphate cement after being treated at different temperatures
  96. Integrating testing and modeling methods to examine the feasibility of blended waste materials for the compressive strength of rubberized mortar
  97. Special Issue on 3D and 4D Printing of Advanced Functional Materials - Part II
  98. Energy absorption of gradient triply periodic minimal surface structure manufactured by stereolithography
  99. Marine polymers in tissue bioprinting: Current achievements and challenges
  100. Quick insight into the dynamic dimensions of 4D printing in polymeric composite mechanics
  101. Recent advances in 4D printing of hydrogels
  102. Mechanically sustainable and primary recycled thermo-responsive ABS–PLA polymer composites for 4D printing applications: Fabrication and studies
  103. Special Issue on Materials and Technologies for Low-carbon Biomass Processing and Upgrading
  104. Low-carbon embodied alkali-activated materials for sustainable construction: A comparative study of single and ensemble learners
  105. Study on bending performance of prefabricated glulam-cross laminated timber composite floor
  106. Special Issue on Recent Advancement in Low-carbon Cement-based Materials - Part I
  107. Supplementary cementitious materials-based concrete porosity estimation using modeling approaches: A comparative study of GEP and MEP
  108. Modeling the strength parameters of agro waste-derived geopolymer concrete using advanced machine intelligence techniques
  109. Promoting the sustainable construction: A scientometric review on the utilization of waste glass in concrete
  110. Incorporating geranium plant waste into ultra-high performance concrete prepared with crumb rubber as fine aggregate in the presence of polypropylene fibers
  111. Investigation of nano-basic oxygen furnace slag and nano-banded iron formation on properties of high-performance geopolymer concrete
  112. Effect of incorporating ultrafine palm oil fuel ash on the resistance to corrosion of steel bars embedded in high-strength green concrete
  113. Influence of nanomaterials on properties and durability of ultra-high-performance geopolymer concrete
  114. Influence of palm oil ash and palm oil clinker on the properties of lightweight concrete
https://doi.org/10.1515/rams-2024-0041
Keywords for this article
cementitious materials; steel fibers; carbon fibers; mechanical properties; physical properties
Creative Commons
BY 4.0

Articles in the same Issue

  1. Review Articles
  2. Effect of superplasticizer in geopolymer and alkali-activated cement mortar/concrete: A review
  3. Experimenting the influence of corncob ash on the mechanical strength of slag-based geopolymer concrete
  4. Powder metallurgy processing of high entropy alloys: Bibliometric analysis and systematic review
  5. Exploring the potential of agricultural waste as an additive in ultra-high-performance concrete for sustainable construction: A comprehensive review
  6. A review on partial substitution of nanosilica in concrete
  7. Foam concrete for lightweight construction applications: A comprehensive review of the research development and material characteristics
  8. Modification of PEEK for implants: Strategies to improve mechanical, antibacterial, and osteogenic properties
  9. Interfacing the IoT in composite manufacturing: An overview
  10. Advances in processing and ablation properties of carbon fiber reinforced ultra-high temperature ceramic composites
  11. Advancing auxetic materials: Emerging development and innovative applications
  12. Revolutionizing energy harvesting: A comprehensive review of thermoelectric devices
  13. Exploring polyetheretherketone in dental implants and abutments: A focus on biomechanics and finite element methods
  14. Smart technologies and textiles and their potential use and application in the care and support of elderly individuals: A systematic review
  15. Reinforcement mechanisms and current research status of silicon carbide whisker-reinforced composites: A comprehensive review
  16. Innovative eco-friendly bio-composites: A comprehensive review of the fabrication, characterization, and applications
  17. Review on geopolymer concrete incorporating Alccofine-1203
  18. Advancements in surface treatments for aluminum alloys in sports equipment
  19. Ionic liquid-modified carbon-based fillers and their polymer composites – A Raman spectroscopy analysis
  20. Emerging boron nitride nanosheets: A review on synthesis, corrosion resistance coatings, and their impacts on the environment and health
  21. Mechanism, models, and influence of heterogeneous factors of the microarc oxidation process: A comprehensive review
  22. Synthesizing sustainable construction paradigms: A comprehensive review and bibliometric analysis of granite waste powder utilization and moisture correction in concrete
  23. 10.1515/rams-2025-0086
  24. Research Articles
  25. Coverage and reliability improvement of copper metallization layer in through hole at BGA area during load board manufacture
  26. Study on dynamic response of cushion layer-reinforced concrete slab under rockfall impact based on smoothed particle hydrodynamics and finite-element method coupling
  27. Study on the mechanical properties and microstructure of recycled brick aggregate concrete with waste fiber
  28. Multiscale characterization of the UV aging resistance and mechanism of light stabilizer-modified asphalt
  29. Characterization of sandwich materials – Nomex-Aramid carbon fiber performances under mechanical loadings: Nonlinear FE and convergence studies
  30. Effect of grain boundary segregation and oxygen vacancy annihilation on aging resistance of cobalt oxide-doped 3Y-TZP ceramics for biomedical applications
  31. Mechanical damage mechanism investigation on CFRP strengthened recycled red brick concrete
  32. Finite element analysis of deterioration of axial compression behavior of corroded steel-reinforced concrete middle-length columns
  33. Grinding force model for ultrasonic assisted grinding of γ-TiAl intermetallic compounds and experimental validation
  34. Enhancement of hardness and wear strength of pure Cu and Cu–TiO2 composites via a friction stir process while maintaining electrical resistivity
  35. Effect of sand–precursor ratio on mechanical properties and durability of geopolymer mortar with manufactured sand
  36. Research on the strength prediction for pervious concrete based on design porosity and water-to-cement ratio
  37. Development of a new damping ratio prediction model for recycled aggregate concrete: Incorporating modified admixtures and carbonation effects
  38. Exploring the viability of AI-aided genetic algorithms in estimating the crack repair rate of self-healing concrete
  39. Modification of methacrylate bone cement with eugenol – A new material with antibacterial properties
  40. Numerical investigations on constitutive model parameters of HRB400 and HTRB600 steel bars based on tensile and fatigue tests
  41. Research progress on Fe3+-activated near-infrared phosphor
  42. Discrete element simulation study on effects of grain preferred orientation on micro-cracking and macro-mechanical behavior of crystalline rocks
  43. Ultrasonic resonance evaluation method for deep interfacial debonding defects of multilayer adhesive bonded materials
  44. Effect of impurity components in titanium gypsum on the setting time and mechanical properties of gypsum-slag cementitious materials
  45. Bending energy absorption performance of composite fender piles with different winding angles
  46. Theoretical study of the effect of orientations and fibre volume on the thermal insulation capability of reinforced polymer composites
  47. Synthesis and characterization of a novel ternary magnetic composite for the enhanced adsorption capacity to remove organic dyes
  48. Couple effects of multi-impact damage and CAI capability on NCF composites
  49. Mechanical testing and engineering applicability analysis of SAP concrete used in buffer layer design for tunnels in active fault zones
  50. Investigating the rheological characteristics of alkali-activated concrete using contemporary artificial intelligence approaches
  51. Integrating micro- and nanowaste glass with waste foundry sand in ultra-high-performance concrete to enhance material performance and sustainability
  52. Effect of water immersion on shear strength of epoxy adhesive filled with graphene nanoplatelets
  53. Impact of carbon content on the phase structure and mechanical properties of TiBCN coatings via direct current magnetron sputtering
  54. Investigating the anti-aging properties of asphalt modified with polyphosphoric acid and tire pyrolysis oil
  55. Biomedical and therapeutic potential of marine-derived Pseudomonas sp. strain AHG22 exopolysaccharide: A novel bioactive microbial metabolite
  56. Effect of basalt fiber length on the behavior of natural hydraulic lime-based mortars
  57. Optimizing the performance of TPCB/SCA composite-modified asphalt using improved response surface methodology
  58. Compressive strength of waste-derived cementitious composites using machine learning
  59. Melting phenomenon of thermally stratified MHD Powell–Eyring nanofluid with variable porosity past a stretching Riga plate
  60. Development and characterization of a coaxial strain-sensing cable integrated steel strand for wide-range stress monitoring
  61. Compressive and tensile strength estimation of sustainable geopolymer concrete using contemporary boosting ensemble techniques
  62. Customized 3D printed porous titanium scaffolds with nanotubes loading antibacterial drugs for bone tissue engineering
  63. Facile design of PTFE-kaolin-based ternary nanocomposite as a hydrophobic and high corrosion-barrier coating
  64. Effects of C and heat treatment on microstructure, mechanical, and tribo-corrosion properties of VAlTiMoSi high-entropy alloy coating
  65. Study on the damage mechanism and evolution model of preloaded sandstone subjected to freezing–thawing action based on the NMR technology
  66. Promoting low carbon construction using alkali-activated materials: A modeling study for strength prediction and feature interaction
  67. Entropy generation analysis of MHD convection flow of hybrid nanofluid in a wavy enclosure with heat generation and thermal radiation
  68. Friction stir welding of dissimilar Al–Mg alloys for aerospace applications: Prospects and future potential
  69. Fe nanoparticle-functionalized ordered mesoporous carbon with tailored mesostructures and their applications in magnetic removal of Ag(i)
  70. Study on physical and mechanical properties of complex-phase conductive fiber cementitious materials
  71. Evaluating the strength loss and the effectiveness of glass and eggshell powder for cement mortar under acidic conditions
  72. Effect of fly ash on properties and hydration of calcium sulphoaluminate cement-based materials with high water content
  73. Analyzing the efficacy of waste marble and glass powder for the compressive strength of self-compacting concrete using machine learning strategies
  74. Experimental study on municipal solid waste incineration ash micro-powder as concrete admixture
  75. Parameter optimization for ultrasonic-assisted grinding of γ-TiAl intermetallics: A gray relational analysis approach with surface integrity evaluation
  76. Producing sustainable binding materials using marble waste blended with fly ash and rice husk ash for building materials
  77. Effect of steam curing system on compressive strength of recycled aggregate concrete
  78. A sawtooth constitutive model describing strain hardening and multiple cracking of ECC under uniaxial tension
  79. Predicting mechanical properties of sustainable green concrete using novel machine learning: Stacking and gene expression programming
  80. Toward sustainability: Integrating experimental study and data-driven modeling for eco-friendly paver blocks containing plastic waste
  81. A numerical analysis of the rotational flow of a hybrid nanofluid past a unidirectional extending surface with velocity and thermal slip conditions
  82. A magnetohydrodynamic flow of a water-based hybrid nanofluid past a convectively heated rotating disk surface: A passive control of nanoparticles
  83. Prediction of flexural strength of concrete with eggshell and glass powders: Advanced cutting-edge approach for sustainable materials
  84. Efficacy of sustainable cementitious materials on concrete porosity for enhancing the durability of building materials
  85. Phase and microstructural characterization of swat soapstone (Mg3Si4O10(OH)2)
  86. Effect of waste crab shell powder on matrix asphalt
  87. Improving effect and mechanism on service performance of asphalt binder modified by PW polymer
  88. Influence of pH on the synthesis of carbon spheres and the application of carbon sphere-based solid catalysts in esterification
  89. Experimenting the compressive performance of low-carbon alkali-activated materials using advanced modeling techniques
  90. Thermogravimetric (TG/DTG) characterization of cold-pressed oil blends and Saccharomyces cerevisiae-based microcapsules obtained with them
  91. Investigation of temperature effect on thermo-mechanical property of carbon fiber/PEEK composites
  92. Computational approaches for structural analysis of wood specimens
  93. Integrated structure–function design of 3D-printed porous polydimethylsiloxane for superhydrophobic engineering
  94. Exploring the impact of seashell powder and nano-silica on ultra-high-performance self-curing concrete: Insights into mechanical strength, durability, and high-temperature resilience
  95. Axial compression damage constitutive model and damage characteristics of fly ash/silica fume modified magnesium phosphate cement after being treated at different temperatures
  96. Integrating testing and modeling methods to examine the feasibility of blended waste materials for the compressive strength of rubberized mortar
  97. Special Issue on 3D and 4D Printing of Advanced Functional Materials - Part II
  98. Energy absorption of gradient triply periodic minimal surface structure manufactured by stereolithography
  99. Marine polymers in tissue bioprinting: Current achievements and challenges
  100. Quick insight into the dynamic dimensions of 4D printing in polymeric composite mechanics
  101. Recent advances in 4D printing of hydrogels
  102. Mechanically sustainable and primary recycled thermo-responsive ABS–PLA polymer composites for 4D printing applications: Fabrication and studies
  103. Special Issue on Materials and Technologies for Low-carbon Biomass Processing and Upgrading
  104. Low-carbon embodied alkali-activated materials for sustainable construction: A comparative study of single and ensemble learners
  105. Study on bending performance of prefabricated glulam-cross laminated timber composite floor
  106. Special Issue on Recent Advancement in Low-carbon Cement-based Materials - Part I
  107. Supplementary cementitious materials-based concrete porosity estimation using modeling approaches: A comparative study of GEP and MEP
  108. Modeling the strength parameters of agro waste-derived geopolymer concrete using advanced machine intelligence techniques
  109. Promoting the sustainable construction: A scientometric review on the utilization of waste glass in concrete
  110. Incorporating geranium plant waste into ultra-high performance concrete prepared with crumb rubber as fine aggregate in the presence of polypropylene fibers
  111. Investigation of nano-basic oxygen furnace slag and nano-banded iron formation on properties of high-performance geopolymer concrete
  112. Effect of incorporating ultrafine palm oil fuel ash on the resistance to corrosion of steel bars embedded in high-strength green concrete
  113. Influence of nanomaterials on properties and durability of ultra-high-performance geopolymer concrete
  114. Influence of palm oil ash and palm oil clinker on the properties of lightweight concrete
Sign up now to receive a 20% welcome discount
Institutional Access
How does access work?
Have an idea on how to improve our website?
Please write us.
© 2025 De Gruyter Brill
Downloaded on 10.9.2025 from https://www.degruyterbrill.com/document/doi/10.1515/rams-2024-0041/html
Scroll to top button