Exploring the potential applications of semi-flexible pavement: A comprehensive review

Thi My Chinh Do; Manh Tuan Nguyen

doi:10.1515/rams-2025-0159

Article Open Access

Exploring the potential applications of semi-flexible pavement: A comprehensive review

Thi My Chinh Do and Manh Tuan Nguyen

Published/Copyright: September 29, 2025

Published by

Become an author with De Gruyter Brill

Submit Manuscript Author Information

From the journal REVIEWS ON ADVANCED MATERIALS SCIENCE Volume 64 Issue 1

Abstract

A semi-flexible pavement (SFP) is formed from two materials of different characteristics, including a porous asphalt mixture (PAM) with flexible properties and hardened cement with rigid properties. Grouting materials and PAM’s porosity play an essential role in SFP, resulting in high-performance pavement. The purpose of the study is to review the authors’ aspects of SFP, focusing on selecting the data to analyze the relationships between factors affecting the characteristics of SFP, materials, technical requirements, and design methods. The study concludes with the gaps in the field, such as the interface material, porosity of PAM, application of AI in analyzing and predicting the properties of SFP, and recycled material using grout cement and PAM. This review provides researchers with a thorough understanding of the design process of SFP and the continuous development of the material to apply on the pavement. Additionally, various relationships related to SFP, grouting materials, and PAM are illustrated through figures, tables, and equations for better comprehension.

Keywords: interface materials; grouting material; cement grout; porous asphalt mixture; semi-flexible pavement

1 Introduction

Semi-flexible pavement (SFP) is a combination of a grouting material and a porous asphalt mixture (PAM), which has been widely researched by authors around the world. Although it was first used in Europe around 1960s, the material has been developed in many countries in Southeast Asia, such as Malaysia [1,2,3], Vietnam [4,5,6,7], Japan [8,9,10,11], and China [12,13,14].

SFP takes advantage of both the hardened cement and asphalt concrete. The benefits of the material were investigated in various aspects, including cracking resistance [15], high strength and stability [16], and rutting resistance [17]. There are several limitations of SFP such as the composite interface [18,19,20,21], a wide range of PAM porosity from 18 to 35% [22,23,24], and the influence of sulfuric acid rain [25]. Therefore, several researchers wanted to improve the drawbacks of SFP by adding additives, namely to improve the connection between two interfaces or find the optimum porosity of PAM. The performance of SFP in the laboratory and the field was investigated by various methods, such as the Marshall stability (MS) test [16,26], indirect tensile strength (ITS) test [27,28], compressive strength test [29,30], and microstructural analysis using X-ray computed tomography [15,31] and scanning electron microscopy [25,32]. Researchers are continuing to make discoveries to achieve the highest performance in using SFP.

This study focuses on reviewing various aspects of SFP material. Detailed work contains selection of significant data from previous studies to draw the relationship between the factors and synthesize the dataset to help the researchers design this material. Information about the study is shown in Figure 1.

Figure 1

Flowchart for reviewing the SFP.

2 Composition of SFP

2.1 Composition and factors of PAM

2.1.1 Bitumen

Asphalt or bitumen is a key material affecting the structural properties of SFP, with its type and content being critical in designing porous asphalt concrete. The bitumen type has little effect on the total air voids [30,33] but is vital for cracking resistance [20]. The high viscosity and low penetration bitumen improves high-temperature strength. Modified asphalt enhances fatigue cracking and low-temperature cracking resistance. Rubber asphalt offers rutting resistance because of enhanced compaction and densification [34], reduced environmental pollution, and lower costs [35]. Styrene–butadiene–styrene (SBS)-modified asphalt has also been widely studied for its application to investigate the properties of SFP [16,36,37,38,39,40,41]. The SBS asphalt performs well and meets all the standard requirements. Low bitumen content weakens aggregate bonding, causing cracking and reduced durability. However, excessive bitumen content can soften the mix at high temperatures [42]. The optimal content (3–5%) is therefore determined using Eq. (1) [43,44] based on three parameters, including compressive strength, tensile strength, and abrasion Cantabro loss [26,45,46]. From these studies, it can be understood that the dosage of bitumen has a relationship with the porosity of asphalt concrete, as shown in Figure 2 [15,19,23,25,42,45].

(1) OAC = α × 3.25 × A 5

Figure 2

Relationship between the content of bitumen and the porosity of asphalt concrete.

with

α = 2.65 γ G and

A = 0.25 × G + 2.3 × S + 12 × s + 135 × f .

OAC is the optimum asphalt content, which presents the amount of bitumen (%), α is the specific gravity of the combined aggregates, G is the percentage retained on a 4.75 mm sieve, S is the percentage passing through the 4.75 mm sieve but retained on the 600 µm sieve, s is the percentage of material passing through the 600 µm sieve and retained on the 75 µm sieve, and f is the percentage of material passing through the 75 µm sieve.

2.1.2 Aggregate gradation analysis

Aggregate gradation is classified into three categories: coarse aggregate (≥4.75 mm), fine aggregate (≤2.36 mm), and filler material (≤0.075 mm), as shown in Figure 3 [26,36,42,47,48,49]. The porosity of the asphalt structure depends on the proportion of coarse and fine aggregate to form the void frame structure and maintain the interconnected voids [26,48]. Larger aggregate sizes increase interconnected voids, enhancing the permeability and grout penetration [50]. However, excessively large sizes cause segregation and weaken particle bonding. A uniform particle size improves void connectivity and lowers internal particle stress [45,51].

Figure 3

Sieve size and aggregate gradation reported by previous authors.

2.1.3 Porosity of PAM

The air void content of the PAM ranges from 18 to 35%, as calculated using Eq. (2), and the interconnected void of PAM is expressed in Eq. (3) [22]. The porosity of PAM has a substantial impact on the performance of SFP. If the porosity is low, cement grout cannot penetrate all void spaces in PAM due to poor interconnectivity. Conversely, high porosity in PAM requires a larger amount of grout, making the pavement more rigid and improving the crack resistance, flexural strength, and stiffness modulus [33,52]. The air void content of PAM ranges from 20 to 26%, resulting in improved performance of compressive strength, flexural strength, ITS, dynamic stability, and modulus of SFP [19,47]. However, when the air void exceeds 25%, a slight reduction in compressive strength, elastic modulus, MS [53], and strain energy density may occur [52]. To ensure optimal performance of the SFP, the porosity of PAM should begin at 25% [19,31,54,55,56].

(2) V = ( 1 − γ 0 γ a ) × 100 ,

(3) V C = ( 1 − m a − m w v ρ w ) × 100 ,

where γ 0 and γ a are the bulk density and theoretical maximum density of PAM (g·cm⁻³), respectively; m a and m w are the weights in air and water (g), respectively; ρ w is the density of water (g·cm⁻³); v is the volume of PAM (cm³); V is the total void in the PAM (%); and V C is the interconnected porosity of PAM (%).

2.1.4 Permeability of PAM

The permeability of PAM is a major factor in ensuring that cement grout penetrates into the porous asphalt skeleton, as calculated using Eq. (4). This property is assessed based on AASHTO standards, which recommend a minimum permeability measurement of 100 m·day⁻¹ [22,42]. Notably, the permeability of PAM is not influenced by bitumen dosage but is primarily affected by aggregate gradation size, fine aggregate content, and porosity. The permeability increased with larger aggregate sizes and higher porosity of PAM. Figure 4 illustrates the correlation between the porosity and permeability of PAM [22,23,42,45].

(4) P = aL At ln h 1 h 2 ,

where a is the area of the top standpipe (cm²), L is the height of PAM (cm), A is the surface area of PAM (cm²), and t is the the time it takes for the slurry to drop from h 1 (30 cm) to h 2 (10 cm) (s).

Figure 4

Permeability of PAM.

2.2 Composition and factors of cement grout

2.2.1 Cement

Cement is a primary component of cement grout. Different types of cements are used for SFP, such as OPC, Portland cement 42.5, Portland cement 32.5, white cement, and sulfoaluminate cement (SAC), which is a low alkali sulfoaluminate. The qualities of several kinds of cement are shown in Table 1. The strength of the cement mortar is influenced by various factors such as the water-to-cement (W/C) ratio, type and dosage of admixtures, and industrial by-products. Most studies used OPC 42.5 for SFP, with only a few employing other types of cements such as SAC, OPC 32.5, and white cement. The relationship between compressive strength and curing time across different cements is shown in Figure 5. The strength values of OPC 42.5 are distributed over a wide range, with the difference between the minimum and maximum values ranging from 3.5 to 6.5 times depending on the curing time. The strength values of other cement types fall within this range, except for OPC 32.5 [1,16,48,57,58,59,60,61,62,63,64,65,66,67,68]. However, the influence of cement types on compressive strength has not been clearly investigated. Therefore, further studies are needed to examine the effect of cement type on compressive strength.

Table 1

Properties of cement used for mortar in SFP

	Chemical
Refs.	Cement	SiO₂ (%)	CaO (%)	Fe₂O₃ (%)	MgO (%)	Al₂O₃ (%)	SO₃ (%)	Loss on ignition (%)
[20]	P.O 42.5	21.51	65.44	4.88	1.99	5.51	0.5	0.48
[69]		20.35	64.66	3.71	0.87	5.57	2.56	2.25
[39]		21.1	65.9	2.5	1.5	4.3	—	—
[70]		23.45	62.13	3.39	2.08	5.24	2.05	—
[71]		23.1	57.6	3.7	2.2	7.1	2.6	2.3
[69]	R.SAC	10.25	48.48	2.16	1.61	18.67	14.36	0.22
[63]	R.SAC	8.56	41.22	3.01	2.41	34.05	9.87	0.62
[62]	P.O 32.5	29.6	46.9	—	1.9	12.1	2.6

	Physical
Refs.	Cement	Surface area (m²·kg⁻¹)	Initial set (min)	Final set (min)	Compressive strength (MPa)		Flexural strength (MPa)
Refs.	Cement	Surface area (m²·kg⁻¹)	Initial set (min)	Final set (min)	3 days or 7 days	28 days	3 days or 7 days	28 days
[69]	P.O 42.5	342	175	203	26.5–3 days	52.1	—	—
[39]		315	228	380	37.8–7 days	43.2	5.92–7 days	6.85
[71]		—	150	225	28.3–3 days	45.7	—	—
[62]	P.O 32.5	—	211	250	13.8–3 days	35.6	2.6–7 days	6.7
[69]	R.SAC	408	9	14	35.8–3 days	45.8	—	—

Figure 5

Compressive strength of different types of cements and curing time.

2.2.2 W/C ratio

The W/C ratio affects the strength and fluidity of semi-flexible materials. A high W/C ratio means a greater amount of water relative to cement, leading to increased fluidity and lower grout strength. Excess water reduces friction between cement particles, enhancing the fluidity. Additionally, voids formed in hardened grout further decrease the strength. Conversely, a lower W/C ratio results in lower fluidity but higher strength [59,72]. The W/C ratio of cement grout without superplasticizer additives has been studied within the range of 0.50.7, resulting in fluidity and compressive strength at 7 days, ranging from 10 to 15 s and 15 to 30 MPa, respectively, as shown in Figure 6 [19,33,73,74]. However, the W/C ratio of cement grout with added superplasticizers was lower, ranging from 0.2 to 0.5, depending on the composition of other materials. Figure 7 shows the relationship between the W/C ratio and fluidity and that between the W/C ratio and compressive strength at one day of cement grout with 0.52% of polycarboxylic ether polymer and without other materials of the authors [57,61,75,76]. The findings showed that the W/C ratio increased, resulting in enhanced fluidity and reduced compression strength. The compressive strength value varies with the same W/C ratio and under superplasticizer conditions. Therefore, the appropriate W/C ratio must be determined based on the specific conditions of the constituent materials in the grout.

Figure 6

Relationship between the W/C ratio, fluidity, and compressive strength.

Figure 7

(a) Relationship of W/C ratio with (a) fluidity and (b) compressive strength at 1 day.

2.2.3 Additives of superplasticizers

Different kinds of superplasticizers are utilized to improve the characteristics of grouting in SFP, including polycarboxylic ether (PCE) polymer, sulfonated naphthalene formaldehyde, and polycarboxylate. Each additive has a different structure and properties, which change the grout performance.

2.2.3.1 PCEs

PCE is a product that combines an anionic backbone of carboxylic groups and side chains of polyethers attached to the backbone with a chemical structure, as shown in Figure 8. The carboxy groups drive the polymer adsorption on the cement surface, increasing dispersion and fluidity, and non-ionic polyether chains tangle into the solution. PCEs can reduce the W/C ratio to values as low as 0.2, withholding good workability [77]. The minimum dosage of PCE made the cement begin to disperse. Above this dosage, the fluidity of grout continues to increase to achieve surface saturation, which is called saturation dosage. Segregation, bleeding, and delay in hardening would occur beyond that dosage [77].

Figure 8

Chemical structure of PCE.

Varying PCE content ranging from 0.5 to 2.5% was investigated to analyze different kinds of pozzolanic materials on the performance of grouting material while ensuring the fluidity of grout applied for SFP [3,32,46,57,67,76,78]. The fluidity of cement mortar should be from 10 to 16 s to penetrate into the porous asphalt concrete [15,18,57,79]. The amount of PCE was 0.5–2% combined with a W/C ratio of 0.3–0.35, and the amount of pozzolanic materials was less than 15%, making fluidity about 10–16 s [3,32,46,75,76]. Most studies used PCE additives to enhance the flowability of grout, and the most common dosage ranged from 1 to 1.5%, corresponding to the W/C ratio of 0.3 and 0.35.

2.2.3.2 Polynaphthelene sulfonate (PNS)

PNS, called superplasticizer or naphthalene sulfonate superplasticizer, is produced by processing condensates of naphthalene sulfonic acid formaldehyde with two steps, called high-range water reducers, because of the high dispersing ability shown in Figure 9 [77]. The addition of PNS to cement grout causes the absorption of PNS by the cement particles. The enhanced fluidity of cement grout is due to its ability to repel one another, scatter particles, and release free water within the flocculation group [80]. Increasing the PNS amount increases the number of PNS molecules on cement particles and the fluidity of grout. When PNS dosage continues to increase, cement particles covered by PNS molecules can reach saturation, resulting in the fluidity of grout not growing [63]. This process takes 5–15 min. Saboo et al. [30] used the grout-modified PNS additive for SFP with sand material. The result showed that increasing PNS dosages ranging from 2 to 6% increased the fluidity from 44 s to under 16 s and decreased the grout’s compression strength at 7 days from 30 MPa to under 17 MPa. However, the strength of cement grout without sand increased from 16.4 to 43.5 MPa, when cured for 7 days, following the addition of PNS amounts from 0.5 to 3.5% [81].

Figure 9

Two steps of condensation to form PNS.

2.2.4 Pozzolanic material

Pozzolanic material is a product of the chemical reaction of siliceous-alumina with calcium hydroxide and water at ordinary temperatures to form more C–S–H gel in the cement grout [72,82,83]. Pozzolanic materials are classified into two types: natural pozzolans, like volcanic-origin zeolite, and artificial pozzolans, including fly ash (FA), slag, and silica fume (SF) [72,82]. The following sections discuss the materials influencing the properties of cement grout.

2.2.4.1 FA

FA is a by-product of coal combustion, with particle sizes ranging from 0.5 to 300 μm. Its composition is complex, primarily consisting of SiO₂, Al₂O₃, and CaO. Depending on burning techniques or coal type, the substances’ content in FA differs, but the amount of SiO₂ is usually high from 50 to 60% [84]. FA replaces cement in cement grout to reduce the amount of CO₂ emission into the environment but ensures the strength of cement mortar to apply for SFP [46,74,75]. FA is a pozzolanic material that reacts with Ca(OH)₂ from cement hydration to form a C–S–H gel, enhancing its strength over time. FA has been combined with various waste materials to replace cement for environmental protection while still ensuring that the properties of cement mortar are applied to SFP. In addition, FA production is decreasing, only meeting a part of the industrial demand. The content of FA depends on the types of materials added to the mortar. In China, Zhang et al. [73] evaluated the efficiency of combining FA with mineral powder (MP) compared to FA with sand for cement grout used for SFP. The research recommended that the mixture with 10% FA and 10% MP has better overall performance for SFP because the sand in the cement grout caused segregation and settlement, reducing the strength of the grout. In Malaysia, Khan et al. [2] combined FA with PET/IrPET into cement grout to use as an SFP because FA meets only a part of the industry’s needs. The results showed that the content of each type of FA and PET, about 10%, caused minor drying shrinkage. Mixing 5% IrPET with 5% or 10% FA can achieve compressive and flexural strengths of 60 and 4 MPa, respectively. Zhao and Yang [74] applied FA and rubber powder in cement grout to associate recycled asphalt pavement to create SFP. The study chose 15% FA and 5% rubber powder to replace cement in grout to modify recycled asphalt concrete, reducing emissions and saving energy.

2.2.4.2 SF

SF produced by processed industrial metallurgical extraction has more than 90% SiO₂, and its particles are non-crystalline with size around 0.1 μm, surface area of about 20,000 m²·kg⁻¹, and a spherical shape. SiO₂ in SF has excellent physical and amorphous properties, making it a pozzolanic material. SF will absorb Ca(OH)₂ of hydration cement to form the C–S–H gel, reducing the permeability and increasing cement grout’s strength and durability [85]. Replacing cement with SF in modified cement grout improves the fluidity and compressive strength of the mixture while enhancing the resistance of the SFP under loading cycles [26,78]. This is because the small particles of SF fill the entire pore space between cement particles or cement grains and aggregates or form bridges connecting the cement particles [61,66,86]. The SF content has been analyzed with different amounts, including 5, 6, 8, 10, and 15%, following the quantity of cement since it depends on the superplasticizer, W/C ratio, and type of cement [1,33,61,66,86]. However, the increased SF content increases the surface area of the SF to absorb water, leading to decreased strength and uncertain fluidity of grout. So, the content of SF used to cement mortar should be about 5% [1,33,61,78,86,87].

2.2.4.3 MP

Technical indexes of MP used in cement grout to modify SFP are presented in Table 2. MP influences the fluidity of mortar by a small amount and makes it weaker by a more significant amount. About 9% MP content causes a minimum dry shrinkage of grout, and about 8% MP content has a more substantial impact on the strength of grout [33]. However, Sun et al. [88] illustrated that MP has no significant effect on the flexural strength, compressive strength, fluidity, and drying shrinkage of cement during curing time, with the MP content ranging from 10 to 20%. Other researchers used MP in cement mixing with different amounts, such as 10% [58,65] and 15% [19], but the influence of MP was not dealt with.

Table 2

Technical specifications of MP

Ref.	Density (g·cm⁻³)	Moisture (%)	Size passing percent (%)
Ref.	Density (g·cm⁻³)	Moisture (%)	0.3 (mm)	0.15 (mm)	0.075 (mm)
[33]	2.65	0.23	100	97.7	87.5
[88]	2.69	0.23	96.6	91	80.94
[58]			92.4		74.4
[65]	2.76	0.27	97.5	92.3	80.34

2.2.4.4 Zeolite

Zeolite is a volcanic natural rock source that is applied in cement construction materials, including cement paste, mortar, and concrete [89] and has pozzolanic properties [89,90,91]. Zeolite is a porous hydrated aluminosilicate [90], with an irregular-angled shape, a light brown color [91], high specific surface area, and an average size of 29 μm [89]. Mixing different amounts of zeolite (10–30%) with cement and water produces the C–S–H gel and ettringite after 1 day of curing. The amount of ettringite reduced after 7 days and caused the pozzolanic reaction of zeolite, forming flower-like shaped C–S–H gels. After 14 days, the structure becomes more compact, resembling a honeycomb; however, the structure shows some microcracks. The pozzolanic reaction continues for up to 28 days, transforming CH into the CSH gel, which creates a denser structure by reducing the number and size of micropores. Zeolite replacement from 10 to 20% gives the grout high durability properties and strength. This outcome is similar to that reported by Kriptavicius et al. [91] and Hamzani et al. [35]. Increasing amounts of zeolite result in larger pores, allowing for more water to be absorbed and stored within the porous structure of zeolite [89]. Cement grout with 15% zeolite produces an SFP featuring a compressive strength of 12–16 MPa, a flexural strength of 0.6 MPa [92], a dry shrinkage of 1–1.5%, and a permeability coefficient under 0.005 cm·s⁻¹ [35].

2.2.5 Interface between the ingredients of SFP

The interface between components in a semi-flexible material includes an interface between asphalt and cement hardened and the interface between asphalt and aggregate. Two connection types are weakest in SFP, and researchers are studying to improve the faces with different additives.

2.2.5.1 Carboxylate styrene–butadiene (XSB)

XSB is a copolymer synthesized by the copolymerization of butadiene and styrene with a small amount of carboxylic acid. It is milky white, has water dispersion, high styrene content, a small benzene ring, a friendly environment [21,92], and a molecular structure. XSB enhances the interface between cement and asphalt concrete, showing cement particles covering asphalt to create good adhesion between the two materials [21]. The addition of XSB strongly influenced the initial hydration of cement. The polymer film of XSB copolymer retards the process of cement hydration and inhibits the evolution of AFm crystals [93,94]. The cement grout-modified XSB penetrates deeply into the porous asphalt structure, enhancing the interface between the two materials, as researched by Xu et al. [21]. The microstructure of the cement–asphalt interface shows an uneven cement surface, with some cracks, which can hinder penetration. In contrast, tiny XSB particles are added to cement mortar to create a strong connection with asphalt. These particles surround the asphalt, improving the bonding between the two materials [92].

2.2.5.2 Styrene–butadiene rubber (SBR)

SBR latex is a group of synthetic rubbers [95] that is a combination of both flexible butadiene chains and rigid styrene chains [95,96], as shown in Figure 10. Adding the SBR latex to fresh cement grout creates a product that combines SBR latex and cement hydration. Two substances are interconnected, working together to create bonding strength [95,96,97].

Figure 10

Chemical structure of the SBR latex.

The physical–chemical reaction between SBR latex and cement particles results in fiber products made as a bridge connecting cement particles and SBR membrane to reinforce the network between hydrated products [62]. Upon analyzing the interface between asphalt and SBR-modified cement through electron microscopy, it was found that the connection between the two materials is limited.

2.2.5.3 Silane coupling agents (SCAs)

SCAs are silicon-based substances with two groups of chemical properties whose typical structure is (RO)₂–Si–R′–X [98]. It can react with both organic and inorganic materials at the same time. The X, R′, and RO, respectively, represent an organic group, such as an amino group, a small alkylene linkage such as –CH₂CH₂, and a hydrolyzable group, such as an alkoxy group, an inorganic group from every aspect [98]. The X interacts with oil in asphalt, and the R′ reacts with inorganic surface groups [16,18,21]. KH-550 or KH-570 is used to enhance asphalt-cement bonding with chemical structures, as shown in Figure 11 [98,99] and Figure 12 [100,101]. SCA hydrated in cement grout can be divided into five stages, including: (i) dissolution, (ii) dynamic balance, (iii) setting, (iv) hardening, and (v) steady hardening. During the first hour, cement particles and hydration products are coated by a gel-like SCA film; after 12 h, denser polycondensates form, binding hydration products and reducing pore connectivity. At 28 days, the improved microstructure results in higher compressive and flexural strength [98]. In asphalt concrete, SCAs react with hydroxyl groups in water and aggregates, forming a thin condensation film with Si–O–Si bonds. Asphalt molecules adsorb onto this film, creating a compact transition zone that improves stress transfer and adhesion [102]. However, when SCA-modified cement grout is embedded in asphalt, the cement–asphalt bond can weaken due to persistent interfacial gaps [21]. Liu et al. [18] found that pre-soaking porous asphalt in SCA before grouting enhances bonding only with low-strength grout (<60 MPa), with no benefit for high-strength grout (>70 MPa). Cheng et al. [16] reported that SCA-modified SFP performed well only under low-temperature and water-stability conditions.

Figure 11

Silane coupling agent KH-550.

Figure 12

Silane coupling agent KH-570.

2.2.5.4 Cationic asphalt emulsion (CAE)

CAE combines asphalt and a cationic emulsifier to form the substance [103], which is positively charged [104,105], NH⁴⁺, and excess water [103,104]. In cement–CAE mixtures, two processes occur: (i) dissolution of C₃S and C₂S into ions ( Ca 2 + , OH − , and H 2 SiO 4 2 − ) followed by CAE adsorption onto silicate particles, forming an asphalt film that inhibits C–S–H gel growth; (ii) cement hydration [103,105]. CAE-modified grout shows lower compressive strength but reduced shrinkage and improved flexural strength [21]. At 5% CAE, fluidity drops by 10%, shrinkage by 5%, flexural strength rises 13%, and compressive strength decreases slightly [21]. The asphalt film at the cement–asphalt interface improves adhesion without cracks [21]. There were no cracks observed, but it was also relatively flat at the interface because of the covering of asphalt film over the cement particles. Cheng et al. [16] obtained the same results as Xu et al. [21], and the force of the cement–asphalt interface investigated by the pull-out test of the SFP before and after adding 5% CAE into cement grout is shown in Table 3. The force and modulus of the interface after adding CAE were 1.4 and 2.2 times higher, respectively, than without CAE. Using microscopic morphology and energy spectrum, it can be found that after adding CAE cement grout into the porous asphalt structure, the correlation between interfaces happened in two steps: (1) the produced hydration cement Ca(OH)₂ interacts with HCl in emulsified asphalt to form CaCl₂, (2) CaCl₂ reacts with 3CaO·Al₂O₃ in cement to form salts. This makes a spatial mesh structure between materials to form a better interpenetrating network structure that causes a good linkage surface with no cracks [16].

Table 3

Modulus and force of surface bonding in SFP before and after modification [16]

Interface type	Maximum test force (N)	Interface modulus (MPa)
Fresh grout-asphalt	83	120.76
Grout with 5% CAE–asphalt	181	413.25

3 Models for analyzing SFP

Various methods, such as statistical models, computational techniques, machine learning models, and artificial neural networks (ANNs), can effectively define and measure the properties of materials. Recently, these methods have been applied to analyze SFP through specialized software.

3.1 Taguchi methodology

The Taguchi methodology is a statistical technique designed to minimize the number of experiments needed while still achieving reliable results. It also helps to identify the most significant input factors. The first step in this method involves determining the input parameters, which are then analyzed to select the appropriate experiments using orthogonal experimental tables. The input factors of cement grout using SFP included the W/C ratio [25,32,33,71,73], amount of superplasticizer [32,71], sand [25,33,73], MP [33,73], and FA [25,73] dosages. Meanwhile, Cheng et al. [16] utilized curing time, vibration frequency, and vibration time as input factors. The factors are shown in different orthogonal tables such as L₈ (2⁷), where “L” is the abbreviated orthogonal table, “8” presents 8 level combinations, “2” presents 2 levels, and “7” presents 7 level factors (Table 4) [25]. It is the same with L₉ (3⁴) [16,71], L₉ (3³) [33], and L₁₆ (4³) [32]. The second step is the output of the most influential factor based on the response table, such as fluidity, compressive strength, flexural strength, and dry shrinkage [25,32,33,71,73]. It provides the optional output parameter by using the S/N ratio that is calculated using Eqs. (5) or (6) depending on each input parameter [32].

(5) S / N ratio = − 10 × log ( 1 / n × ∑ y 2 ) ,

(6) S / N ratio = − 10 × log ( 1 / n × ∑ ( 1 y ) 2 ) ,

where y is the response for a given factor level combination; n is the number of responses in the factor level combination.

Table 4

L₈ (2⁷) orthogonal form [25]

Number	Column number
Number	1	2	3	4	5	6	7
1	1	1	1	1	1	1	1
2	1	1	1	2	2	2	2
3	1	2	2	1	1	2	2
4	1	2	2	2	2	1	1
5	2	1	2	1	2	1	2
6	2	1	2	2	1	2	1
7	2	2	1	1	2	2	1
8	2	2	1	2	1	1	2

3.2 Response surface method (RSM)

The RSM is a mathematical and statistical model used to design experiments, predict the responses, and establish relationships between independent and dependent variables [2]. It was used to design, model, and optimize the cement grout composition via Box Behnken design (BBD) to reduce experiments or central composite design (CCD) to explore extreme points [2,106]. Khan et al. [2] used the RSM with CCD to analyze the factors of percentage dosages of PET and FA and the dependence of SF on variables such as fluidity, drying shrinkage, compressive strength, and flexural strength [1]. Khan et al. [79] also investigated the same with factors such as the W/C ratio and superplasticization on cement grout’s fluidity and compressive strength. In addition, Zhang et al. [106] used the RSM with BBD to study the effect of W/C ratio, sodium oxide content, and powder quality ratio on the fluidity, strength, and dry shrinkage of grout. The experiments have a design, as shown in Table 5. The factors were run from 16, 17, or 21 experiments to obtain an optimal mixing ratio. The results of the experiment response complied with a second-degree polynomial equation with two or three independent variables, as shown in Eq. (7). The predicted results of dependent and independent variables will be expressed in the form of Eqs. (8)–(13) [1].

(7) Y = β 0 + ∑ β i X i + ∑ β ii X i 2 + ∑ β ij X i X j ,

where Y is the predicted response, β 0 is the intercept, β i is a linear coefficient, β ii is a quadratic coefficient, β ij is the interaction coefficient, and X _i and X _j are independent variables.

(8) Flow = 11.44 − 0.02 × X 1 + 0.01 × X 2 + 0.1 X 1 2 + 0.043 X 2 2 ,

(9) Drying shrinkage = 4.13 − 0.03 × X 1 + 0.05 × X 2 ,

(10) Compressive strength ( 1 day ) = 28.5 − 2.0 × X 1 + 0.2 × X 2 ,

(11) Compressive strength ( 7 ‐ days ) = 40.827 − 2.3585 × X 1 + 1.762 × X 2 + 0.049 × X 1 2 − 0.0608 × X 2 2 − 0.025 × X 1 × X 2 ,

(12) Compressive strength ( 28 ‐ days ) = 58.265 − 2.392 × X 1 + 2.92 × X 2 − 0.203 × X 2 2 ,

(13) Flexural strength ( 28 ‐ days ) = 7.009 − 0.063 × X 1 + 0.092 × X 2 − 0.00172 × X 1 2 − 0.0004 × X 2 2 − 0.0009 × X 1 × X 2 ,

where X 1 represents the amount of N-PET (%); X 2 represents the amount of SF (%).

Table 5

Design factors in the RSM

Ref.	Factors	Units	Code	Levels
Ref.	Factors	Units	Code	−α	−1	0	+1	+α
[2]	PET/Ir PET	%	X₁	0	—	5	—	10
[2]	FA	%	X₂	0	—	5	—	10
[1]	PET-N/PET-Ir	%	X₁	0	—	5	—	10
[1]	SF	%	X₂	0	—	5	—	10
[79]	W/C ratio	—		0.25	0.3	0.35	0.4	0.45
[79]	Superplasticizer	%		0	0.5	1.0	1.5	2
[106]	W/C ratio	—	X₁	—	0.42	0.45	0.48	—
	Sodium oxide content	%	X₂	—	4	5	6	—
	Powder quality ratio	—	X₃	—	7/3	6/4	5/5	—
[107]	W/C ratio	—	X₁	—	0.35	0.425	0.5	—
[107]	Waste marble dust	%	X₂	—	0	12.5	25	—

3.3 ANNs

An ANN is a parallel distributed processing system in which the input layer evolves into an output after passing through one or more hidden layers called neurons. These networks are made up of several components that are referred to as neurons or nodes and are needed for data processing. The activation or inhibition of a specific neuron depends on a set of parameters known as the activation function. To predict the output, the input data are mapped into a generalized function and then transmitted to the following layer through the hidden layer [108]. Khan et al. [109] used the ANN to analyze the effect of grout components on fluidity and compressive strength. The parameters of the input layers, such as PET, FA, SF, and OPC contents, were evaluated through a hidden layer containing 10 neurons. The output results are based on several model developments with different mathematical equations [109,110]. By running several experiments, ANNs can produce the predicted output, including compressive strength and fluidity of cement grout, quite accurately with deviations not too far from the experimental values [109].

4 Test methods

The summary of the results of various performance tests for SFP is shown in Table 6.

4.1 Uniaxial compressive test (UCT)

The UCT for cube samples with dimensions of 40 mm × 40 mm × 80 mm [39,52] were cured for 28 days at 20°C and humidity ≥90%. The loading rate of 50 mm·min⁻¹ was used at 20 and 60°C to test uniaxial compressive strength, elastic modulus, and strain energy density (G, J·m⁻³) of SFP samples. The SFP material destruction model by the uniaxial compression test describes the material destruction process into four stages: compaction stage, elastic deformation stage, crack initiation stage, and completely deactivated and correspond to failure patterns. The SFP was cured for different times such as 7, 14, and 28 days to determine the mechanical characteristics of the material [39]. Compressive strength (R _C), compressive strain (ε _C), and stiffness modulus (S _C) were calculated using Eqs. (14)–(16), respectively.

(14) R C = P C / ( b × h ) ,

(15) ε C = ∆ L / L ,

(16) S C = R C / ε C ,

where b, h, and L are the length, width, and height of samples, respectively; P _C is the maximum load; ΔL is the damage deformation at the corresponding maximum load.

4.2 Triaxial compressive test (TCT)

The TCT simulates the three-dimensional behavior of the pavement structures by applying stresses in multiple directions [111]. The cylindrical specimens (65 mm × 130 mm) of SFP were cured for 28 days, wrapped in a rubber membrane, conditioned at 60°C for 5 h, and then compressed at 7 mm·min⁻¹ under confining pressures of 0, 138, 276, and 414 kPa [31]. The failed model of SFP in the TCT was highly complicated with a non-linear stress–strain relationship. Unlike the uniaxial test, the triaxial test showed no initial compaction stage. The damage process can be divided into four steps: initial stage (samples undamaged, with many pores unfilled by mortar), elastic deformation stage (a linear elastic behavior observed in the stress–strain curve), damage initiation stage (microcracks form and propagate under accumulated stress, expanding to weak areas, and merging into larger cracks, resulting in vertical deformation), and damage propagation stage (after peak stress, the main crack extends vertically through the specimen, leading to complete failure) [31].

4.3 ITS tests

The ITS test was used to determine the tensile strength of a cylindrical specimen by applying a compressive load across a vertical diametrical plane. The vertical compressive load was applied at a constant rate of 50 mm·min⁻¹. The maximum load was recorded to calculate the ITS, as shown in Eq. (17) [44,112]. There were two types of specimens in the test. Group 1 consisted of samples conditioned at 25°C in a water bath for 2 h before testing. Group 2 consisted of samples conditioned at −16°C for 24 h, followed by placement in a 60°C environment for 24 h. The purpose was to determine the TSR ratio of two groups, as shown in Eq. (18). The higher TSR value indicates that the specimens have good resistance to moisture damage [44,70] because the cement grout prevented water from entering the voids of the asphalt structure [26].

(17) ITS = ( 2,000 × P ) / ( π × t × D ) ,

(18) TSR = ( ITS 2 / ITS 1 ) × 100 % ,

where ITS is the ITS strength (kPa); P is the maximum load (N); t is the height of specimens before the test (mm); D is the diameter of the specimen (mm). TSR presents the tensile strength ratio; ITS 1 and ITS 2 present the average of the ITS in the first and second groups, respectively.

4.4 MS test

The MS test, following the ASTM D6927-15, was used to determine the deformation resistance of SFP. The samples are cylinders with a diameter of 101.6 mm and a height of 63.5 mm applied with a constant load rate of 50 mm·min⁻¹, and cured at 3 days, 7 days, and 28 days in the water tank. The MS value increased with curing time due to the hydration process of the cement [32].

4.5 Wheel tracking test (WTT)

The WTT, following EN 12697-22 standard, was conducted on plate specimens (300 mm × 300 mm × 50 mm) to evaluate the rutting resistance and dynamic stability of SFP [37,113]. The PAM slabs were compacted with a roller at 130°C, then infiltrated with cement grout at 20°C for 1 day, and conditioned at 60°C for 5 h [26,37]. A steel wheel with a 15 mm rubber layer applied a vertical load of 686 N and a horizontal reciprocating motion (300 cycles·min⁻¹ over 300 mm) for 1 h, with deformation measured between 45 and 60 min. Dynamic stability, calculated by Eq. (19), reflects the number of cycles needed for 1 mm rut depth [37,39]. The results showed that higher grout strength improved dynamic stability, and SFP exhibited lower rutting rates and greater hardness than PAM due to grout reinforcement [37,113].

(19) DS = 42 × t 2 − t 1 d 2 − d 1 ,

where DS is the dynamic stability, d 1 is the central deflection at 45 min ( t 1 ), and d 2 is the deflection at 60 min ( t 2 ).

4.6 Indirect tensile fatigue test (ITFT)

ITFT evaluates SFP fatigue performance by applying repeated vertical loads to cylindrical specimens (100 mm diameter; 45–60 mm height) cored from the slabs or prepared by the Marshall method. Loading at 2 Hz (0.1 s of loading and 0.4 s of rest time) continued until failure or major cracking. Stress levels were set as 0.2–0.7 times the ITS value [46,114], or 250–950 kPa [27,115]. Test results relate fatigue life to applied stress or stress ratio, as shown in Eq. (20). However, according to Corradini et al. [27] the relationship between the number of fatigue life and the applied stress is expressed by Eq. (21).

(20) N f = A × σ − a ,

(21) log ⁡ ( N f ) = log ( α ) + β × log ( σ ) + γ × log ( E ) ,

where N f is the number of cycles to failure, σ is the applied stress, A and a are the regression coefficients of obtained experimental data. α , β , and γ are the regression parameters, and E is the stiffness modulus.

SFP showed higher fatigue resistance than hot mix asphalt (HMA) [27,46,114,115,116], with field performance exceeding laboratory results [115]. Fatigue resistance depends on grout additives and base layer stiffness. Waterborne epoxy resin reduces fatigue life, while emulsified asphalt and carboxyl latex improve it [116].

4.7 Four-point bending fatigue test

The four-point bending fatigue test was used to evaluate the fatigue resistance of SFP by providing repeated sinusoidal loading at a frequency range of 5 to 10 Hz according to AASHTO T 321-14. During the experiment, the specimen was placed on two supports and subjected to repeated loading at two points equidistant from the beam center, creating a region of constant bending moment. Stress levels of 200, 225, 250, 400, or 500 microstrain were applied to the beam of length 380 mm × 50 mm × 63.5 mm at a temperature of 20°C until failure occurs or stiffness decreases by 50% compared to the initial value [54,117,118,119]. The result is the relationship between the number of fatigue lives and strain, as shown in Eq. (22) [118].

(22) N f = A × ε − B ,

where N f is the number of fatigue lives (times), ε is the strain level, and A and B are the fitting coefficients.

The fatigue performance of SFP is higher than that of PAM and depends on various factors [117,118]. The fatigue life increases as the asphalt film thickness increases from 6 to 10 μm. To enhance the fatigue resistance of SFP, the asphalt-to-aggregate ratio should be greater than 6.7% or the asphalt film thickness should exceed 10 μm [118]. The fatigue performance was further improved by using surface bonding agents such as SCAs. The fatigue life increases by 10.9, 28.5, and 251.1% after interfacial enhancement using SCA [117] (Table 6).

Table 6

Summary of the test of the performance of SFP

Ref.	Components of grout	Components of PAM	UCT (MPa)	MS (kN)	ITS (MPa) and TSR	WTT (DS (cycles/mm)	Flexural strength (MPa)
[44]	Type I-II cement, FA, and superplasticizer	PG64-22 binder			2.23–2.33
[44]	Type I-II cement, FA, and superplasticizer	PG64-22 binder			TSR = 0.97
[70]	OPC cement, SF, and CAE	23–27% PAM	17–28 at 28 days; 12–26 at 7 days	10–30	0.9–1.2	3,000–16,000	1.5–3 at 7 days; 3.5–4 at 28 days
[70]	OPC cement, SF, and CAE	23–27% PAM	17–28 at 28 days; 12–26 at 7 days	10–30	TSR = 0.74–0.89	3,000–16,000	1.5–3 at 7 days; 3.5–4 at 28 days
[32]	OPC cement, sand, and superplasticizer	PBM 40 and VG 30 and 28–30% PAM		27–83	0.9–2.6
[32]	OPC cement, sand, and superplasticizer	PBM 40 and VG 30 and 28–30% PAM		27–83	TSR = 0.89–1.0
[26]	OPC cement, fine sand, SF, or FA	20–30% PAM		30–50	1.5–2.3	10,000
[26]	OPC cement, fine sand, SF, or FA	20–30% PAM		30–50	TRS: 0.85–0.95	10,000
[52]	UNIKRETE G30B high-performance cement	SBS binder, plasticizer, anti-aging agent, and 20%, 25%, and 30% PAM	2–3 at 60°C			40,000–125,000
[52]	UNIKRETE G30B high-performance cement		9–11 at 20°C			40,000–125,000
[56]	UNIKRETE G30B high-performance cement and PAM 25%	A70 asphalt, thermoplastic rubber, resin, anti-aging agent, plasticizer, and 20%, 25%, and 30% PAM	5–11 at 20°C
[39]	FA, fine sand, and superplasticizer	SBS modified asphalt, 24% PAM with 1.18 to 13.2 mm slag powder	10–16			39,375–63,000	6–9
[38]	JGM^®-301 grouting material	SBS modified asphalt, limestone, and lignin fibers					4.5 at −5°C
							3.8 at 15°C
							1.4 at 35°C
[3]	OPC, PET, FA, and PCE	Coarse and fine aggregates and 30–31% PAM		40–43	1.5–1.6		3.2–4.2
[3]	OPC, PET, FA, and PCE	Coarse and fine aggregates and 30–31% PAM		40–43	TSR = 0.94–0.95		3.2–4.2
[28]	JGM-301^® grouting materials	SBS binder, limestone MP, 17% to 23% PAM			0.75–0.85 at 25°C	25,000–31,000	7–8
					1.25–1.75 at −10°C
					TSR: 0.85–1.0
[120]	Specific cement, metakaolin, calcined silt, KOH, NaOH, and 20–30% PAM	PmB 25/55 binder, limestone filler, cellulose fibers, and 25–26% PAM			1.55–2.16
[120]					TSR: 0.87–0.93
[37]	Utrarapid cement: C3S, SiO₂, gypsum, and polyacrylate polymer	Polymer asphalt with SBS		21–24		31,500	2.9–3.2
[65]	OPC, sand, carboxyl latex, and minerals	Emulsified, organic additive, foamed asphalt, and 20–32% PAM			1.13–1.26	18,000–80,000	6.69–7.04
[113]	OPC, TH-928 polycarboxylate, UEA agent, and ZY-99 agent	A-70 matrix asphalt, TAFPACK super, and 18–24% PAM	6–7 at 20°C	8–14		20,000–30,000	5–7
			2–3 at 40°C
			1–2 at 60°C

5 Failure mechanisms of SFP

5.1 Fatigue mechanism

In SFP, fatigue is the gradual loss of load-bearing capacity under repeated traffic loading. The main mechanism is tensile stress accumulation at the bottom of the surface layer, especially in the PAM–grout transition zone. The process occurs in three stages: 1) at low stress ratios or temperatures, cracks initiate in the asphalt phase as stress exceeds its fatigue limit, while the stiffer grout remains intact; 2) with higher stress ratios and temperatures, cracks develop in both asphalt and grout, and in some cases the brittle grout fails first. Asphalt modulus decreases with temperature, shifting more stress to the grout and increasing its presence on fracture surfaces; 3) at stress ratios above 0.7 or at high temperatures, both phases degrade rapidly – softened asphalt and overstressed grout allow cracks to spread quickly, causing severe structural damage in a shorter time [38].

5.2 Interfacial failure mechanism

5.2.1 Interfacial failure mechanism by applying loads

The interfacial failure process of SFP occurs in three stages. (1) Elastic deformation – internal microcracks are minimal and plane porosity remains nearly unchanged and closely resembles that of the initial state [31]. (2) Damage initiation – stress concentrated at voids and at the interfaces between cement, asphalt, and aggregate, leading to the formation of microcracks that link into macrocracks, marking the onset of plastic deformation in the material [31,121]. (3) Damage propagation – after the peak stress is reached, cracks propagate rapidly along weak interfaces such as aggregate–asphalt–aggregate, cement–asphalt–aggregate, and through the cement mortar itself. The main cracks widen and slip, forming a distinct failure plane, while internal voids accelerate complete structural breakdown [31,121].

5.2.2 Interfacial bonding mechanism by nanoindentation tests

In addition to investigating material failure mechanisms under loading, nanoindentation techniques have also been increasingly employed in recent years to evaluate the interfacial bonding between different phases in the SFP [122,123,124]. Using nanoindentation, researchers have identified that the SFP contains various interfacial transition zones (ITZs). According to Cai et al., there are four interface transition zones (ITZs) in the SFP: 1) the ITZ in the aggregate–asphalt phase, 2) the original asphalt mastic phase, 3) the ITZ in the asphalt mastic–cement phase on the asphalt side, and 4) the ITZ in the asphalt mastic–cement phase on the cement side [123]. Liu et al. utilized nanoindentation tests to assess the bonding characteristics across these zones. The aggregate–asphalt ITZ was identified as the weakest, both before and after treatment with a SCA. However, more cracking was observed in the asphalt–grout ITZ [122]. According to Wang et al., the cement–asphalt interface is generally the weakest interfacial zone in the SFP. However, this interfacial bond can be effectively reinforced by using emulsified asphalt, which improves adhesion and microstructural integrity [124].

6 Structure design and field performance

6.1 Structural design

The structural design of SFP is typically based on a porous asphalt skeleton with the air void content ranging from 20 to 30% [125], which is considered optimal to ensure grout penetration while maintaining a mechanical interlock of approximately 25% [34,56]. This configuration allows for the full-depth penetration of cement-based grout. The thickness of the SFP surface layer varies from 4 to 15 cm, depending on the traffic loading and pavement function. Thicker sections are often used in heavy-duty applications such as intersections and airfields [34,56,126]. The base layer is generally a semi-rigid, cement-treated layer, or HMA which provides sufficient support and reduces deformation under repeated loading. The cement grout used for filling the voids is often enhanced with polymers, micro-silica, or other admixtures, offering high compressive strength and improved flexural properties. Laboratory studies and finite element modeling confirm that such a structure provides excellent fatigue resistance and rutting control when properly constructed. Mechanized grout application methods with vibration have proven more effective than manual methods, ensuring consistent filling and improved durability.

6.2 Field performance

Field results from various projects around the world have demonstrated the outstanding performance of SFP under heavy loads and harsh environmental conditions. In terms of load-bearing capacity and stiffness, SFP core samples collected after 2–10 years of service showed a significant increase in stiffness, mainly due to bitumen oxidation and cement grout hardening, particularly in the study of Spadoni et al. [115]. At Copenhagen Airport (Denmark), SFP with thicknesses ranging from 90 to 100 mm has been successfully implemented in high-load areas such as aircraft stands for type E aircraft, with over 300,000 m² constructed between 1988 and 2000. This system has demonstrated clear economic benefits, saving up to 50% in costs compared to traditional Portland cement concrete pavements [127]. Regarding fatigue resistance, field samples exhibited significantly better performance than laboratory specimens, especially under high strain levels. This improvement is attributed to densification under repeated loading and bitumen aging. In ports such as Thessaloniki (Greece) and Ravenna (Italy), SFP has maintained impermeability, wear resistance, and high load capacity after more than a decade in service [115]. In Singapore and Malaysia, the SFP system has proven to be highly durable, with a service life of up to 12 years without maintenance, making it effective for bus terminals, industrial roads, and container yards [125]. Furthermore, the SFP has demonstrated excellent rutting resistance and raveling resistance, even at high temperatures and under heavy rainfall, with rutting depths smaller than 3.6 mm after 2 years of heavy traffic and excellent fatigue life, confirmed by SCB, IDT, and APT studies [34,52]. Field inspections revealed that after 2 years in service, SFP maintained high dynamic stability, impermeability, mechanical strength, and resistance to raveling [115].

7 Conclusions and prospects

Based on previous research, this study has reviewed the performance of SFP to help new researchers understand composite materials and develop new methods for evaluating the quality of SFP. The main conclusions include the following:

There is a wide range of PAM porosity from 18 to 35%.
The W/C ratio is an important parameter of grout affected by various additives. To ensure the strength, fluidity, and cracking resistance of grout, the W/C ratio should be evaluated separately for different additives.
Researchers investigated the interface connection of additives between hardened cement and PAM, and it should be used for SFP. However, the kind of additive could continue to be explored for good achievement of interface bonding.
Pozzolan materials should be used to replace cement to reduce carbon emissions throughout the environment. However, the content should be less than 20% to ensure the strength of cement in the early ages for traffic.
Artificial intelligence (AI) has gained popularity in different fields and has recently been utilized by some researchers to predict SFP performance. The application of AI combined with experimental testing should be further studied to evaluate the AI’s potential in determining material performance.

Acknowledgments

The authors acknowledge the support of time and facilities provided by Ho Chi Minh City University of Technology (HCMUT), VNU-HCM, for carrying out this study. The authors also acknowledge Nguyen Tat Thanh University, Ho Chi Minh City, Vietnam, for supporting this study.

Funding information: The authors state no funding involved.
Author contributions: All authors have accepted responsibility for the entire content of this manuscript and approved its submission.
Conflict of interest: The authors state no conflict of interest.
Data availability statement: All data generated or analyzed during this study are included in this published article.

References

[1] Khan, M. I., M. H. Sutanto, M. B. Napiah, K. Khan, and W. Rafiq. Design optimization and statistical modeling of cementitious grout containing irradiated plastic waste and silica fume using response surface methodology. Construction and Building Materials, Vol. 271, 2020, id. 121504.10.1016/j.conbuildmat.2020.121504Search in Google Scholar

[2] Khan, M. I., M. H. Sutanto, M. B. Napiah, S. E. Zoorob, N. I. M. Yusoff, A. Usman, et al. Irradiated polyethylene terephthalate and fly ash based grouts for semi-flexible pavement: Design and optimisation using response surface methodology. International Journal of Pavement Engineering, Vol. 23, No. 8, 2020, pp. 2515–2530.10.1080/10298436.2020.1861446Search in Google Scholar

[3] Khan, M. I., M. H. Sutanto, M. B. Napiah, S. E. Zoorob, A. M. Al-Sabaeei, W. Rafiq, et al. Investigating the mechanical properties and fuel spillage resistance of semi-flexible pavement surfacing containing irradiated waste PET based grouts. Construction and Building Materials, Vol. 304, 2021, id. 124641.10.1016/j.conbuildmat.2021.124641Search in Google Scholar

[4] Đào, V. Đ. Nghiên cứu ứng dụng mặt đường bán mềm cho xây dựng mặt đường cấp cao ở Việt Nam. Tạp chí Giao thông vận tải, Vol. 5, 2011, pp. 22–27.Search in Google Scholar

[5] Nguyễn, M. H. and Đ. V. Cao. Kết quả nghiên cứu bước đầu vật liệu bê tông nhựa vữa xi măng tự chèn. Khoa học và công nghệ, Vol. 5, 2016, pp. 75–77.Search in Google Scholar

[6] Infrasol Company. Kết quả thi công bê tông nhựa vữa vinkems asphalsol (Thí điểm Quốc lộ 1A, lý trình Km1912 + 561.5 đến Km1912 + 661.5).Infrasol.vn, 2018, https://infrasol.vn/wp-content/uploads/2019/01/baocaokythuat.pdf.Search in Google Scholar

[7] Nguyễn, M. T., Đ.T. Nguyễn, N. M. T. Phan, T. Á. H. Lâm, Đ. D. Lăng, and B. T. Vũ. Nghiên cứu thiết kế vữa tự chèn gốc Styrene butadiene ứng dụng cho mặt đường bán mềm. Tạp chí xây dựng, Vol. 6, 2019, pp. 99–102.Search in Google Scholar

[8] 富山アスファルト工事相談所. 大粒径アスファルト舗装、半たわみ性舗装とは？特徴や適用箇所、注意事項をご紹介！.Japan, 2022, 28/2/2022 https://asphalt-navi.com/column/646/2/.Search in Google Scholar

[9] 八谷好高, 坪川将丈. 半たわみ性材料によるオーバーレイの現場試験施工. 土木学会舗装工学論文集, Vol. 6, 2001, pp. 209–17.Search in Google Scholar

[10] 八谷好高, 坪川将丈, 勤喜董. 半たわみ性材料による空港アスファルト舗装の補修設計. 土木学会舗装工学論文集, Vol. 7, 2002, id. 21p1–21p10.Search in Google Scholar

[11] 進清, 浩巳藤, 正知丸. 論文半たわみ性舗装に使用するセメントミルクの充填性に関する研究. コンクリート工学年次論文集, Vol. 39, No. 1, 2017, pp. 1279–1284.Search in Google Scholar

[12] 牟长江, 程凯, 刘瑞. 灌注式半柔性路面材料性能研究综述. 材料科学, Vol. 1, No. 4, 2021, pp. 405–410.10.12677/MS.2021.114048Search in Google Scholar

[13] 杨宇亮!, 张肖宁, 王树森, 张宏伟. 半柔性混合料的设计与性能研究. 山东交通学院学报, Vol. 11, No. 3, 2003, pp. 32–41.Search in Google Scholar

[14] 李生隆, 孙登科, 胡玲玲. 半柔性复合路面设计与施工方法的探讨水利与建筑工程学报, Vol. 5, No. 4, 2007, pp. 70–74.Search in Google Scholar

[15] Cai, X., Z. Leng, P. Kumar Ashish, J. Yang, and M. Gong. Quantitative analysis of the role of temperature in the mesoscale damage process of semi flexible pavement composite through finite element method. Theoretical and Applied Fracture Mechanics, Vol. 124, 2023, id. 103742.10.1016/j.tafmec.2022.103742Search in Google Scholar

[16] Cheng, P., G. Ma, and Y. Li. Preparation and performance improvement mechanism investigation of high-performance cementitious grout material for semi-flexible pavement. Polymers (Basel), Vol. 15, No. 12, 2023, id. 2631.10.3390/polym15122631Search in Google Scholar PubMed PubMed Central

[17] Pan, B., H. Zhang, S. Liu, M. Gong, and J. Yang. Dynamic responses of semi-flexible pavements used for the autonomous rail rapid transit. Applied Sciences, Vol. 13, No. 6, 2023, id. 3673.10.3390/app13063673Search in Google Scholar

[18] Liu, X., K. Wu, X. Cai, W. Huang, and J. Huang. Influence of the composite interface on the mechanical properties of semi-flexible pavement materials. Construction and Building Materials, Vol. 397, 2023, id. 132466.10.1016/j.conbuildmat.2023.132466Search in Google Scholar

[19] Zhang, Z., J. Li, and F. Ni. Material innovation preparation and performance study of semi-flexible pavement materials. Case Studies in Construction Materials, Vol. 17, 2022, id. e01355.10.1016/j.cscm.2022.e01355Search in Google Scholar

[20] Wu, K., X. Liu, X. Cai, W. Huang, J. Yu, and G. Nie. Performance and fracture analysis of composite interfaces for semi-flexible pavement. Coatings, Vol. 11, No. 10, 2021, id. 1231.10.3390/coatings11101231Search in Google Scholar

[21] Xu, Y., Y. Jiang, J. Xue, X. Tong, and Y. Cheng. High-performance semi-flexible pavement coating material with the microscopic interface optimization. Coatings, Vol. 10, No. 3, 2020, id. 268.10.3390/coatings10030268Search in Google Scholar

[22] Ling, S., Y. Sun, D. Sun, and D. Jelagin. Pore characteristics and permeability simulation of porous asphalt mixture in pouring semi-flexible pavement. Construction and Building Materials, Vol. 330, 2022, id. 127253.10.1016/j.conbuildmat.2022.127253Search in Google Scholar

[23] Setyawan, A. Design and properties of hot mixture porous asphalt for semi-flexible pavement applications. Jurnal penelitian Media Teknik Sipil, 2005, pp. 41–45.Search in Google Scholar

[24] Wang, D., X. Liang, D. Li, H. Liang, and H. Yu. Study on mechanics-based cracking resistance of semiflexible pavement materials. Advances in Materials Science and Engineering, Vol. 2018, 2018, id. 8252347.10.1155/2018/8252347Search in Google Scholar

[25] Hu, C., Z. Zhou, and Y. Luo. Study on damage evolution and mechanism of semi-flexible pavement under acid rain erosion. Case Studies in Construction Materials, Vol. 19, 2023, id. e02286.10.1016/j.cscm.2023.e02286Search in Google Scholar

[26] Kumar, S. and S. Kumar Suman. Investigating the properties of cement grouted bituminous mix with alternative grout compositions. Materials Today: Proceedings, Vol. 65, 2022, pp. 831–838.10.1016/j.matpr.2022.03.335Search in Google Scholar

[27] Corradini, A., G. Cerni, A. D’Alessandro, and F. Ubertini. Improved understanding of grouted mixture fatigue behavior under indirect tensile test configuration. Construction and Building Materials, Vol. 155, 2017, pp. 910–918.10.1016/j.conbuildmat.2017.08.048Search in Google Scholar

[28] Gong, M., Z. Xiong, C. Deng, G. Peng, L. Jiang, and J. Hong. Investigation on the impacts of gradation type and compaction level on the pavement performance of semi-flexible pavement mixture. Construction and Building Materials, Vol. 324, 2022, id. 126562.10.1016/j.conbuildmat.2022.126562Search in Google Scholar

[29] Setyawan, A. Asessing the compressive strength properties of semi-flexible pavements. Procedia Engineering, Vol. 54, 2013, pp. 863–874.10.1016/j.proeng.2013.03.079Search in Google Scholar

[30] Saboo, N., V. Khalpada, P. K. Sahu, R. Radhakrishnan, and A. Gupta. Optimal proportioning of grout constituents using mathematical programming for semi flexible pavement. International Journal of Pavement Research and Technology, Vol. 12, No. 3, 2019, pp. 297–306.10.1007/s42947-019-0036-xSearch in Google Scholar

[31] Ling, S., P. Igor Itoua, D. Sun, and D. Jelagin. Damage characterization of pouring semi-flexible pavement material under triaxial compressive load based on X-ray computed tomography. Construction and Building Materials, Vol. 348, 2022, id. 128653.10.1016/j.conbuildmat.2022.128653Search in Google Scholar

[32] Kumar, D. H., R. K. Chinnabhandar, K. Chiranjeevi, and A. U. R. Shankar. Effect of aggregate gradation and bitumen type on mechanical properties of semi-flexible asphalt mixtures. Case Studies in Construction Materials, Vol. 18, 2023, id. e02025.10.1016/j.cscm.2023.e02025Search in Google Scholar

[33] Jiahong, W. Research on crack resistance of semi-flexible pavement materials. In 3rd International Conference on Civil Architecture and Energy Science (CAES 2021), Vol. 248, EDP Sciences, Hangzhou, China, 2021, id. 01020.10.1051/e3sconf/202124801020Search in Google Scholar

[34] Zhao, Z., L. Xu, X. Li, X. Guan, and F. Xiao. Comparative analysis of pavement performance characteristics of flexible, semi-flexible and rigid pavement based on accelerated pavement tester. Construction and Building Materials, Vol. 387, 2023, id. 131672.10.1016/j.conbuildmat.2023.131672Search in Google Scholar

[35] Hamzani, Munirwansyah, M. Hasan, and S. Sugiarto. Determining the properties of semi-flexible pavement using waste tire rubber powder and natural zeolite. Construction and Building Materials, Vol. 266, 2021, id. 121199.10.1016/j.conbuildmat.2020.121199Search in Google Scholar

[36] An, S., C. Ai, D. Ren, A. Rahman, and Y. Qiu. Laboratory and field evaluation of a novel cement grout asphalt composite. Journal of Materials in Civil Engineering, Vol. 30, No. 8, 2018, pp. 04018179(1)–04018179(9).10.1061/(ASCE)MT.1943-5533.0002376Search in Google Scholar

[37] Bang, J. W., B. J. Lee, and Y. Y. Kim. Development of a semirigid pavement incorporating ultrarapid hardening cement and chemical admixtures for cement grouts. Advances in Materials Science and Engineering, Vol. 2017, 2017, pp. 1–9.10.1155/2017/4628690Search in Google Scholar

[38] Wang, S., H. Zhou, X. Chen, M. Gong, J. Hong, and X. Shi. Fatigue resistance and cracking mechanism of semi-flexible pavement mixture. Materials (Basel), Vol. 14, No. 18, 2021, id. 5277.10.3390/ma14185277Search in Google Scholar PubMed PubMed Central

[39] Yang, Q., Y. Li, H. Zou, L. Feng, N. Ru, L. Gan, et al. Study of the effect of grouting material strength on semiflexible pavement material. Advances in Materials Science and Engineering, Vol. 2022, 2022, id. 5958896.10.1155/2022/5958896Search in Google Scholar

[40] Fan, J., M. Gong, L. Jiang, J. Cheng, S. Li, Z. Li, et al. Interlayer failure characteristics of semi-flexible composite pavement structures (SFCPS) at high temperatures. Construction and Building Materials, Vol. 441, 2024, id. 137563.10.1016/j.conbuildmat.2024.137563Search in Google Scholar

[41] Songqiang, C., Z. Jian, W. Xi, and C. Zining. Research on innovative preparation and performance of semi flexible pavement materials. Case Studies in Construction Materials, Vol. 20, 2024, id. e03050.10.1016/j.cscm.2024.e03050Search in Google Scholar

[42] Saboo, N., R. Ranjeesh, A. Gupta, and M. Suresh. Development of hierarchical ranking strategy for the asphalt skeleton in semi-flexible pavement. Construction and Building Materials, Vol. 201, 2019, pp. 149–158.10.1016/j.conbuildmat.2018.12.131Search in Google Scholar

[43] Ahlrich, R. C. and G. L. Anderton. Construction and evaluation of resin modified pavement. In Tech Rept GL-91-13, Department of the Army US Army corps of Engineers, Washington, DC, Vicksburg, MS, USA, 1991.Search in Google Scholar

[44] Zhang, W., S. Shen, R. D. Goodwin, D. Wang, and J. Zhong. Performance characterization of semi-flexible composite mixture. Materials (Basel), Vol. 13, No. 2, 2020, id. 342.10.3390/ma13020342Search in Google Scholar PubMed PubMed Central

[45] Guo, X. and P. Hao. Influential factors and evaluation methods of the performance of grouted semi-flexible pavement (GSP)—A review. Applied Sciences, Vol. 11, No. 15, 2021, id. 6700.10.3390/app11156700Search in Google Scholar

[46] Khan, M. I., M. H. Sutanto, S. H. Khahro, S. E. Zoorob, M. N. I. Yusoff, A. M. Al-Sabaeei, et al. Fatigue prediction model and stiffness modulus for semi-flexible pavement surfacing using irradiated waste polyethylene terephthalate-based cement grouts. Coatings, Vol. 13, No. 1, 2022, id. 76.10.3390/coatings13010076Search in Google Scholar

[47] Khan, M. I., M. H. Sutanto, N. I. M. Yusoff, S. E. Zoorob, W. Rafiq, M. Ali, et al. Cementitious grouts for semi-flexible pavement surfaces-A review. Materials (Basel), Vol. 15, No. 15, 2022, id. 5466.10.3390/ma15155466Search in Google Scholar PubMed PubMed Central

[48] Zhang, H., S. Liang, Y. Ma, and X. Fu. Study on the mechanical performance and application of the composite cement–asphalt mixture. International Journal of Pavement Engineering, Vol. 20, No. 1, 2016, pp. 44–52.10.1080/10298436.2016.1255530Search in Google Scholar

[49] Yu, S., S. Shen, H. Huang, and C. Zhang. Engineered semi-flexible composite mixture design and its implementation method at railroad bridge approach. Transportation Research Record: Journal of the Transportation Research Board, Vol. 2675, No. 9, 2021, pp. 789–797.10.1177/03611981211004981Search in Google Scholar

[50] Husain, N. M., M. R. Karim, H. B. Mahmud, and S. Koting. Effects of aggregate gradation on the physical properties of semiflexible pavement. Advances in Materials Science and Engineering, Vol. 2014, 2014, pp. 1–8.10.1155/2014/529305Search in Google Scholar

[51] Ding, Q. J., Z. Sun, F. Shen, and S. L. Huang. The performance analysis of semi-flexible pavement by the volume parameter of matrix asphalt mixture. Advanced Materials Research, Vol. 168–170, 2010, pp. 351–356.10.4028/www.scientific.net/AMR.168-170.351Search in Google Scholar

[52] Ling, S., Z. Chen, D. Sun, H. Ni, Y. Deng, and Y. Sun. Optimal design of pouring semi-flexible pavement via laboratory test, numerical research, and field validation. Transportation Research Record: Journal of the Transportation Research Board, Vol. 2676, No. 11, 2022, pp. 479–495.10.1177/03611981221093631Search in Google Scholar

[53] Yang, B. and X. Weng. The influence on the durability of semi-flexible airport pavement materials to cyclic wheel load test. Construction and Building Materials, Vol. 98, 2015, pp. 171–175.10.1016/j.conbuildmat.2015.08.092Search in Google Scholar

[54] Li, G., H. Xiong, Q. Ren, X. Zheng, and L. Wu. Experimental study and performance characterization of semi-flexible pavements. Coatings, Vol. 12, No. 2, 2022, id. 241.10.3390/coatings12020241Search in Google Scholar

[55] Jiang, D., D. Wang, Z. Chen, L. Fan, and J. Yi. Research on the mesoscopic viscoelastic property of semi-flexible pavement mixture based on discrete element simulation. Case Studies in Construction Materials, Vol. 17, 2022, id. e01282.10.1016/j.cscm.2022.e01282Search in Google Scholar

[56] Ling, S., M. Hu, D. Sun, H. Ni, and L. Xu. Mechanical properties of pouring semi-flexible pavement material and engineering estimation on contribution of each phase. Construction and Building Materials, Vol. 315, 2022, id. 125782.10.1016/j.conbuildmat.2021.125782Search in Google Scholar

[57] Koting, S., H. Mahmud, and M. R. Karim. Influence of superplasticizer type and dosage on the workability and strength of cementitious grout for semi-flexible pavement application. Journal of the Eastern Asia Society for Transportation Studies, Vol. 7, 2007, pp. 2156–2167.Search in Google Scholar

[58] Ling, T.-Q., Z.-J. Zhao, C.-H. Xiong, Y.-Y. Dong, Y.-Y. Liu, and Q. Dong. The application of Semi-flexible pavement on heavy traffic road. International Journal of Pavement Research and Technology, Vol. 2, No. 5, 2009, pp. 211–217.Search in Google Scholar

[59] Wang, Y. J., C. Y. Guo, Y. F. Tian, and J. J. Wang. Design of mix proportion of cement mortar with high-performance composite semi-flexible pavement. Advanced Materials Research, Vol. 641-642, 2013, pp. 342–345.10.4028/www.scientific.net/AMR.641-642.342Search in Google Scholar

[60] Huang, C., J. X. Hong, J. T. Lin, C. Deng, and L. Li. Utilization of waste rubber powder in semi-flexible pavement. Key Engineering Materials, Vol. 599, 2014, pp. 361–367.10.4028/www.scientific.net/KEM.599.361Search in Google Scholar

[61] Koting, S., M. R. Karim, H. B. Mahmud, and N. A. Abdul Hamid. Mechanical properties of cement-bitumen composites for semi-flexible pavement surfacing. The Baltic Journal of Road and Bridge Engineering, Vol. 9, No. 3, 2014, pp. 191–199.10.3846/bjrbe.2014.24Search in Google Scholar

[62] Fang, B., T. Xu, and S. Shi. Laboratory study on cement slurry formulation and its strength mechanism for semi-flexible pavement. Journal of Testing and Evaluation, Vol. 44, No. 2, 2016, pp. 907–913.10.1520/JTE20150230Search in Google Scholar

[63] Zhang, G., G. Li, and Y. Li. Effects of superplasticizers and retarders on the fluidity and strength of sulphoaluminate cement. Construction and Building Materials, Vol. 126, 2016, pp. 44–54.10.1016/j.conbuildmat.2016.09.019Search in Google Scholar

[64] Luo, S., X. Yang, K. Zhong, and J. Yin. Open-graded asphalt concrete grouted by latex modified cement mortar. Road Materials and Pavement Design, Vol. 21, No. 1, 2018, pp. 61–77.10.1080/14680629.2018.1479290Search in Google Scholar

[65] Wang, D., X. Liang, C. Jiang, and Y. Pan. Impact analysis of Carboxyl Latex on the performance of semi-flexible pavement using warm-mix technology. Construction and Building Materials, Vol. 179, 2018, pp. 566–575.10.1016/j.conbuildmat.2018.05.173Search in Google Scholar

[66] Husain, N. M., N. N. Ismail, K. M. Ismail, D. Syamsunur, and M. M. Taib. Development of high workability grout on semi rigid wearing course. IOP Conference Series: Materials Science and Engineering, Vol. 512, 2019, pp. 012–033.10.1088/1757-899X/512/1/012033Search in Google Scholar

[67] Wismadi, A., N. Chairunnisa, A. F. Fardheny, P. A. P. Agustiananda, M. Fauziah, B. Kushari, et al. The study of flowability and the compressive strength of grout/mortar proportions for pre- placed concrete aggregate (PAC). MATEC Web of Conferences, Vol. 280, 2019, id. 04010.10.1051/matecconf/201928004010Search in Google Scholar

[68] Davoodi, A., M. Aboutalebi Esfahani, M. Bayat, and S. E. Mohammadyan-Yasouj. Evaluation of performance parameters of cement mortar in semi-flexible pavement using rubber powder and nano silica additives. Construction and Building Materials, Vol. 302, 2021, id. 124166.10.1016/j.conbuildmat.2021.124166Search in Google Scholar

[69] Liu, W., Y. Jiang, Z. Zhao, R. Du, and H. Li. Material innovation and performance optimization of multi-solid waste-based composite grouting materials for semi-flexible pavements. Case Studies in Construction Materials, Vol. 17, 2022, id. e01624.10.1016/j.cscm.2022.e01624Search in Google Scholar

[70] Zarei, S., J. Ouyang, W. Yang, and Y. Zhao. Experimental analysis of semi-flexible pavement by using an appropriate cement asphalt emulsion paste. Construction and Building Materials, Vol. 230, 2020, id. 116994.10.1016/j.conbuildmat.2019.116994Search in Google Scholar

[71] Pei, J., J. Cai, D. Zou, J. Zhang, R. Li, X. Chen, et al. Design and performance validation of high-performance cement paste as a grouting material for semi-flexible pavement. Construction and Building Materials, Vol. 126, 2016, pp. 206–217.10.1016/j.conbuildmat.2016.09.036Search in Google Scholar

[72] Kosmatka, S. H., B. Kerkhoff, and W. C. Panarese. Design and control of concrete mixturers, Portland Cement Association, Illinois, USA, 2003.Search in Google Scholar

[73] Zhang, J., J. Cai, J. Pei, R. Li, and X. Chen. Formulation and performance comparison of grouting materials for semi-flexible pavement. Construction and Building Materials, Vol. 115, 2016, pp. 582–592.10.1016/j.conbuildmat.2016.04.062Search in Google Scholar

[74] Zhao, W. and Q. Yang. Performance characterization and life cycle assessment of semi-flexible pavement after composite modification of cement-based grouting materials by desulfurization ash, fly ash, and rubber powder. Construction and Building Materials, Vol. 359, 2022, id. 129549.10.1016/j.conbuildmat.2022.129549Search in Google Scholar

[75] Khan, M. I., H. Y. Huat, M. Dun, M. H. Sutanto, E. N. Jarghouyeh, and S. E. Zoorob. Effect of irradiated and non-irradiated waste pet based cementitious grouts on flexural strength of semi-flexible pavement. Materials (Basel), Vol. 12, No. 24, 2019, id. 4133.10.3390/ma12244133Search in Google Scholar PubMed PubMed Central

[76] Vijaya, S. S. A., M. R. Karim, H. Mahmud, and N. F. Ishak. Influence of superplasticiser on properties of cementitious grout used in semi-flexible pavement. In The Eastern Asia society for transportation studiesThe 8th International Conference of Eastern Asia Society for Transportation Studies, 2009, Vol. 7, Chiyoda-Ku, Tokyo, Japan, 2009.Search in Google Scholar

[77] Flatt, R. and I. Schober. Superplasticizers and the rheology of concrete. In Understanding the rheology of concrete, Woodhead Publishing Limited, Sawston, Cambridge, United Kingdom, 2012, pp. 144–208.10.1533/9780857095282.2.144Search in Google Scholar

[78] Koting, S., M. R. Karim, H. Mahmud, and N. A. A. Hamid. Development of cement-bitumen composites for semi-flexible pavement surfacing. In The Eastern Asia society for transportation studies, Vol. 8, 2011, pp. 20–23.Search in Google Scholar

[79] Khan, M. I., M. H. Sutanto, M. B. Napiah, M. Zahid, and A. Usman. Optimization of cementitious grouts for semi-flexible pavement surfaces using response surface methodology. IOP Conference Series: Earth and Environmental Science, Vol. 498, No. 1, 2020, id. 012004.10.1088/1755-1315/498/1/012004Search in Google Scholar

[80] El-Gamal, S. M. A., F. M. Al-Nowaiser, and A. O. Al-Baity. Effect of superplasticizers on the hydration kinetic and mechanical properties of Portland cement pastes. Journal of Advanced Research, Vol. 3, No. 2, 2012, pp. 119–124.10.1016/j.jare.2011.05.008Search in Google Scholar

[81] Anagnostopoulos, C. A. Effect of different superplasticisers on the physical and mechanical properties of cement grouts. Construction and Building Materials, Vol. 50, 2014, pp. 162–168.10.1016/j.conbuildmat.2013.09.050Search in Google Scholar

[82] Dondson, V. H. Pozzolans and the Pozzolanic reaction. In Concrete admixture, Springer, Boston, MA, USA, 1990, pp. 159–201.10.1007/978-1-4757-4843-7_7Search in Google Scholar

[83] Ahmed, A., J. Kamau, J. Pone, F. Hyndman, and H. Fitriani. Chemical reactions in pozzolanic concrete. Modern Approaches on Material Science, Vol. 1, No. 4, 2019, pp. 128–133.10.32474/MAMS.2019.01.000120Search in Google Scholar

[84] Bhatt, A., S. Priyadarshini, A. Acharath Mohanakrishnan, A. Abri, M. Sattler, and S. Techapaphawit. Physical, chemical, and geotechnical properties of coal fly ash: A global review. Case Studies in Construction Materials, Vol. 11, 2019, id. e00263.10.1016/j.cscm.2019.e00263Search in Google Scholar

[85] Alhajiri, A. M. and M. N. Akhtar. Enhancing sustainability and economics of concrete production through silica fume: A systematic review. Civil Engineering Journal, Vol. 9, No. 10, 2023, pp. 2612–2629.10.28991/CEJ-2023-09-10-017Search in Google Scholar

[86] Fang, Y., X. Wang, L. Jia, C. Liu, Z. Zhao, C. Chen, et al. Synergistic effect of polycarboxylate superplasticizer and silica fume on early properties of early high strength grouting material for semi-flexible pavement. Construction and Building Materials, Vol. 319, 2022, id. 126065.10.1016/j.conbuildmat.2021.126065Search in Google Scholar

[87] Koting, S., M. R. Karim, H. Mahmud, N. S. Mashaan, M. R. Ibrahim, H. Katman, et al. Effects of using silica fume and polycarboxylate-type superplasticizer on physical properties of cementitious grout mixtures for semiflexible pavement surfacing. Scientific World Journal, Vol. 2014, 2014, id. 596364.10.1155/2014/596364Search in Google Scholar PubMed PubMed Central

[88] Sun, Y., Y. Cheng, M. Ding, X. Yuan, and J. Wang. Research on properties of high-performance cement mortar for semiflexible pavement. Advances in Materials Science and Engineering, Vol. 2018, 2018, id.4613074.10.1155/2018/4613074Search in Google Scholar

[89] Toma, I. O., G. Stoian, M. M. Rusu, I. Ardelean, N. Cimpoesu, and S. M. Alexa-Stratulat. Analysis of pore structure in cement pastes with micronized natural zeolite. Materials (Basel), Vol. 16, No. 13, 2023, id. 4500.10.3390/ma16134500Search in Google Scholar PubMed PubMed Central

[90] Woszuk, A. and W. Franus. A review of the application of zeolite materials in warm mix asphalt technologies. Applied Sciences, Vol. 7, No. 3, 2017, pp. 293–308.10.3390/app7030293Search in Google Scholar

[91] Kriptavicius, D., G. Girskas, and G. Skripkiunas. Use of natural zeolite and glass powder mixture as partial replacement of Portland cement: The effect on hydration, properties and porosity. Materials (Basel), Vol. 15, No. 12, 2022, id. 4219.10.3390/ma15124219Search in Google Scholar PubMed PubMed Central

[92] Xu, J., B. Hong, G. Lu, T. Li, S. Wang, C. Wang, et al. Carboxylated styrene-butadiene latex (XSB) in asphalt modification towards cleaner production and enhanced performance of pavement in cold regions. Journal of Cleaner Production, Vol. 372, 2022, id. 133653.10.1016/j.jclepro.2022.133653Search in Google Scholar

[93] Wang, R., X. Liu, and X. Yue. Effect of carboxylated styrene–butadiene copolymer on the hydration of tricalcium aluminate in the presence of gypsum and calcium hydroxide. Journal of Thermal Analysis and Calorimetry, Vol. 147, No. 4, 2021, pp. 3015–3023.10.1007/s10973-021-10670-0Search in Google Scholar

[94] Baueregger, S., M. Perello, and J. Plank. Influence of carboxylated styrene–butadiene latex copolymer on Portland cement hydration. Cement and Concrete Composites, Vol. 63, 2015, pp. 42–50.10.1016/j.cemconcomp.2015.06.004Search in Google Scholar

[95] Ali, A. S., H. S. Jawad, and I. S. Majeed. Improvement the Properties of cement mortar by Using Styrene Butadiene Rubber Polymer. Journal of Engineering and Sustainable Development, Vol. 16, No. 3, 2012, pp. 61–72.Search in Google Scholar

[96] Wang, R., R. Lackner, and P. M. Wang. Effect of styrene–butadiene rubber latex on mechanical properties of cementitious materials highlighted by means of nanoindentation. Strain, Vol. 47, No. 2, 2011, pp. 117–126.10.1111/j.1475-1305.2008.00549.xSearch in Google Scholar

[97] Xiao, J., W. Jiang, D. Yuan, A. Sha, and Y. Huang. Effect of styrene–butadiene rubber latex on the properties of modified porous cement-stabilised aggregate. Road Materials and Pavement Design, Vol. 19, No. 7, 2017, pp. 1702–1715.10.1080/14680629.2017.1337042Search in Google Scholar

[98] Chen, B., H. Shao, B. Li, and Z. Li. Influence of silane on hydration characteristics and mechanical properties of cement paste. Cement and Concrete Composites, Vol. 113, 2020, id. 103743.10.1016/j.cemconcomp.2020.103743Search in Google Scholar

[99] Wang, Z., Y. Liu, H. Li, and M. Sun. Effect of enhancement of interface performance on mechanical properties of shape memory alloy hybrid composites. Composite Interfaces, Vol. 25, No. 2, 2017, pp. 169–186.10.1080/09276440.2017.1353838Search in Google Scholar

[100] Hu, H., Z. Cheng, H. Song, H. Li, H. Wang, Y. Wang, et al. Preparation and properties of loess-based hydrophobic materials. Materials Chemistry and Physics, Vol. 305, 2023, id. 127962.10.1016/j.matchemphys.2023.127962Search in Google Scholar

[101] Li, G., J. Yue, C. Guo, and Y. Ji. Influences of modified nanoparticles on hydrophobicity of concrete with organic film coating. Construction and Building Materials, Vol. 169, 2018, pp. 1–7.10.1016/j.conbuildmat.2018.02.191Search in Google Scholar

[102] Cui, B. and H. Wang. Molecular interaction of asphalt-aggregate interface modified by silane coupling agents at dry and wet conditions. Applied Surface Science, Vol. 572, 2022, id. 151365.10.1016/j.apsusc.2021.151365Search in Google Scholar

[103] Li, W., Y. Fan, L. Hua, Z. Liu, Z. Mao, and J. Hong. Influence of cationic asphalt emulsion on the water transportation behavior and durability of cement mortar. Case Studies in Construction Materials, Vol. 17, 2022, id. e01548.10.1016/j.cscm.2022.e01548Search in Google Scholar

[104] Merten, E. W. and J. R. Wright. Cationic asphalt emulsions: How they differ from conventional emulsions in theory and practice. Materials and Construction, Vol. 38, 1959, pp. 386–397.Search in Google Scholar

[105] Li, W., Z. Mao, G. Xu, H. Chang, J. Hong, H. Zhao, et al. Study on the early cement hydration process in the presence of cationic asphalt emulsion. Construction and Building Materials, Vol. 261, 2020, id. 120025.10.1016/j.conbuildmat.2020.120025Search in Google Scholar

[106] Zhang, Y., Y. Wang, Z.-G. Wu, Y.-M. Lu, A.-H. Kang, and P. Xiao. Optimal design of geopolymer grouting material for semi-flexible pavement based on response surface methodology. Construction and Building Materials, Vol. 306, 2021, id. 124779.10.1016/j.conbuildmat.2021.124779Search in Google Scholar

[107] Khan, M. N., M. I. Khan, J. H. Khan, S. Ahmad, and R. W. Azfar. Exploring waste marble dust as an additive in cementitious grouts for semi-flexible pavement applications: Analysis and optimization using RSM. Construction and Building Materials, Vol. 411, 2024, id. 134554.10.1016/j.conbuildmat.2023.134554Search in Google Scholar

[108] Gurney, K. Neural networks—an overview. In An introduction to neural networks, UCL Press, New Fetter Lane, Lon Don, 1997, pp. 1–18.10.4324/9780203451519Search in Google Scholar

[109] Khan, M. I., M. H. Sutanto, K. Khan, M. Iqbal, M. B. Napiah, S. E. Zoorob, et al. Effective use of recycled waste PET in cementitious grouts for developing sustainable semi-flexible pavement surfacing using artificial neural network (ANN). Journal of Cleaner Production, Vol. 340, 2022, id. 130840.10.1016/j.jclepro.2022.130840Search in Google Scholar

[110] Khan, M. I., N. Khan, S. R. Z. Hashmi, M. R. M. Yazid, N. I. M. Yusoff, R. W. Azfar, et al. Prediction of compressive strength of cementitious grouts for semi-flexible pavement application using machine learning approach. Case Studies in Construction Materials, Vol. 19, 2023, id. e02370.10.1016/j.cscm.2023.e02370Search in Google Scholar

[111] Wang, J., A. A. A. Molenaar, M. F. C. van de Ven, and S. Wu. Behaviour of asphalt concrete mixtures under tri-axial compression. Construction and Building Materials, Vol. 105, 2016, pp. 269–274.10.1016/j.conbuildmat.2015.12.036Search in Google Scholar

[112] ASTM D6931-12. Standard test method for indirect tensile (IDT) strength of bituminous mixtures, ASTM International, West Conshohocken, Pennsylvania, USA, 2012.Search in Google Scholar

[113] Cai, J., J. Pei, Q. Luo, J. Zhang, R. Li, and X. Chen. Comprehensive service properties evaluation of composite grouting materials with high-performance cement paste for semi-flexible pavement. Construction and Building Materials, Vol. 153, 2017, pp. 544–556.10.1016/j.conbuildmat.2017.07.122Search in Google Scholar

[114] Zarei, S., J. Ouyang, and Y. Zhao. Evaluation of fatigue life of semi-flexible pavement with cement asphalt emulsion pastes. Construction and Building Materials, Vol. 349, 2022, id. 128797.10.1016/j.conbuildmat.2022.128797Search in Google Scholar

[115] Spadoni, S., A. Graziani, and F. Canestrari. Laboratory and field investigation of grouted macadam for semi-flexible pavements. Case Studies in Construction Materials, Vol. 16, 2022, id. e00853.10.1016/j.cscm.2021.e00853Search in Google Scholar

[116] Liang, X. and B. Xie. Analysis of the effect of the cement mortar admixture on the fatigue resistance of the semi-flexible pavement. In Advances in Machinery, Materials Science and Engineering Application (Advances in Transdisciplinary Engineering, IOS Press, Wuhan, China, 2022.10.3233/ATDE220428Search in Google Scholar

[117] Liu, X., K. Wu, G. Giacomello, Y. Yue, F. Ren, X. Cai, et al. Enhancing cracking resistance in semi-flexible pavements using an interfacial immersion method. Case Studies in Construction Materials, Vol. 22, 2025, id. e04311.10.1016/j.cscm.2025.e04311Search in Google Scholar

[118] Song, J., B. Chen, M. Sun, K. Wu, J. Chen, and X. Cai. Study on the improvement of fatigue and crack resistance of semi-flexible pavement materials using the mixing -molding method. Construction and Building Materials, Vol. 450, 2024, id. 138728.10.1016/j.conbuildmat.2024.138728Search in Google Scholar

[119] Oliveira, J., J. C. Pais, N. H. Thom, and S. E. Zoorob. A study of the fatigue properties of grouted macadams. International Journal of Pavements, Vol. 6, No. 1–2–3, 2007, pp. 112–123.Search in Google Scholar

[120] Solouki, A., P. Tataranni, and C. Sangiorgi. Thermally treated waste silt as geopolymer grouting material and filler for semiflexible pavements. Infrastructures, Vol. 7, No. 8, 2022, id. 99.10.3390/infrastructures7080099Search in Google Scholar

[121] Chen, Z., S. Ling, D. Sun, L. Xu, and Y. Wu. Research on cracking characteristics and failure modes of semi-flexible pavement materials. Construction and Building Materials, Vol. 452, 2024, id. 138915.10.1016/j.conbuildmat.2024.138915Search in Google Scholar

[122] Liu, X., K. Wu, B. Ni, Y. Li, Y. Yue, X. Cai, et al. Microcosmic mechanism of reinforced interfacial transition zone in SFP materials: An insight from micro- and nano-scale tests. Construction and Building Materials, Vol. 481, 2025, id. 141521.10.1016/j.conbuildmat.2025.141521Search in Google Scholar

[123] Cai, X., J. Zhang, H. Zhang, Z. Yao, X. Chen, and J. Yang. Identification of microstructural characteristics in semi-flexible pavement material using micromechanics and nano-techniques. Construction and Building Materials, Vol. 246, 2020, id. 118426.10.1016/j.conbuildmat.2020.118426Search in Google Scholar

[124] Wang, Y., D. Li, Y. Xu, R. Chen, H. Zhao, and J. Ren. Damage mechanisms of cement–asphalt interface within semi-flexible pavement materials under fatigue state, Vol. 48, No. 7, 2025, pp. 2919–2932.10.1111/ffe.14654Search in Google Scholar

[125] Zhang, Y. and D. Q. Wu. General applications of the semi-rigid pavement in South East Asia. International Journal of Pavement Research and Technology, Vol. 13, No. 3, 2020, pp. 296–302.10.1007/s42947-020-0114-1Search in Google Scholar

[126] Gong, M., Z. Xiong, H. Chen, C. Deng, X. Chen, J. Yang, et al. Evaluation on the cracking resistance of semi-flexible pavement mixture by laboratory research and field validation. Construction and Building Materials, Vol. 307, 2019, pp. 387–395.10.1016/j.conbuildmat.2019.02.064Search in Google Scholar

[127] Mayer, J. and M. Thau. Jointless pavements for heavy-duty airport application: The semi-flexible approach. In Advancing Airfield Pavements, American Society of Civil Engineers (ASCE), Reston, VA, USA, 2001, pp. 87–100.10.1061/40579(271)7Search in Google Scholar

Received: 2025-08-16

Revised: 2025-08-16

Accepted: 2025-08-28

Published Online: 2025-09-29

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

Articles in the same Issue

https://doi.org/10.1515/rams-2025-0159

Keywords for this article

interface materials; grouting material; cement grout; porous asphalt mixture; semi-flexible pavement

Creative Commons

BY 4.0