Evaluation of the mechanical and dynamic properties of scrimber wood produced from date palm fronds

1 Introduction

The discipline of research pertaining to metals and their composites is of significant interest due to their exceptional mechanical and dynamic capabilities [1,2,3,4,5]. Nevertheless, the wood industry continues to be seen as a secondary business in various sectors, despite its inherent capacity to offer environmentally friendly and superior-quality materials. Several decades ago, researchers began publishing their findings on palm wood [6,7]. Due to their low density and poor mechanical properties, most fast-growing tree species were used to make pulp and paper. Several studies have examined engineered wood products made from fast-growing tree species to fulfill the increased need for wood-based structural components. Reconstituted wood panels like particleboard are made from low-grade wood [8]. The majority of its early settlements were in regions of the Middle East and Malaysia with a high concentration of palm palms [9]. The purpose of using palm waste and investigating the mechanical behavior of many kinds of industrial wood was considered, and research was conducted on using rachises in manufacturing hardboard [10,11,12,13,14]. Particleboards created from fast-growing wood have been studied extensively, and previous studies reveal that density and press time are the primary criteria controlling their qualities [15,16]. Several quick-growing tree species, including Scots pine (Pinus sylvestris), radiata pine, eucalyptus, poplar, and Gmelina arborea, have all been utilized to make laminated veneer lumber. Previous studies show that laminated wood has higher bending strength and modulus than solid wood of the same species. Inner plies of laminated composites made from fast-growing tree species may lower production costs without significantly compromising mechanical performance [17,18,19]. Natural fibers, including those from date palms and wood chips, were tested for their impact on soil brick samples’ mechanical and physical qualities [20].

I-beams from fast-growing wood may be used in roofing and flooring applications [21]. Thus, oil palm frond makes boards without glue or adhesive. Given these features, binderless boards from oil palm frond steam-explosion fibers, the authors provide an example of how palm fronds may be incorporated into particleboards [22]. The mechanical properties of the palm fronds were studied by Liu et al. [23]. The authors measured mechanical parameters, including elastic modulus, average rupture strain, ultimate tensile strength (UTS), and shear strength on the surfaces of the different pieces prepared from different parts of a palm leaf. The results showed that the surfaces of the fiber sheet obtained from the leaf sheath showed lower values of the UTS and the shear strength compared to those obtained from the leaf midrib; thus, the fiber sheet obtained from the leaf sheath can be used as a filler for particleboard. The palm wood-based particleboard was compared with particleboard based on [24]. The palm wood-based particleboard showed higher tensile strength than the particleboard based on wood chips. It was found that the mechanical properties of particleboard were significantly affected by the properties of the fibers used in the preparation of the boards. The addition of 30–40% of palm frond fibers into particleboard significantly improved its mechanical properties compared to conventional particleboard [25,26].

The mechanical characteristics and hygroscopicity of compressed earth blocks filled with date palm fibers (DPFs) valorize local construction resources and reduce housing costs, particularly in rural regions [27]. Several fiberboards were made by binding stalks and leaflets from date palms using specific binders. Low- and high-density fiberboards were used to make heat-insulating panels. Interior walls and dividers were manufactured from hard fiberboards. It was a common practice to construct sturdy exterior walls using date palm leaflet fiberboards reinforced with date palm stalks [28]. Particleboard samples were created from Barhi, Saqie, and Sukkari date palm fine and coarse frond particles. Hot water extraction and physical and mechanical properties were tested [29]. This study’s early results may encourage the use of underused species in value-added panel goods, alleviating a critical Saudi Arabian environmental issue. The creation of multiple DPL composite panels and the effect of resin type, fiber orientation, and processing pressure on the heat conductivity were investigated [30]. The physicochemical, thermal, and morphological properties of epoxy resin reinforced with date palm leaf fibers were studied as a function of surface modification and fiber concentration (5, 10, 15, 20, and 25 wt%) [31]. The residues obtained from palm trees include 28.7% leaflets, 27.1% rachis, 23.9% petiole, 6.3% fibrillium, 5.5% spathes, 4.9% bunches, 3.3% pedicels, and 0.8% thorns. DPFs have been used as a reinforcement for thermoplastic and thermoset polymers in an effort to boost the physical, mechanical, and thermal characteristics of these materials. There was an increase in interfacial adhesion and, therefore, mechanical and thermal characteristics in the PP composites due to the incorporation of DPF [32]. Flexural strength, modulus, and epoxy composites’ thermal and dynamic mechanical characteristics were investigated as a function of DPF loading (40, 50, and 60 wt%) [33]. DPF- and KF-reinforced epoxy hybrid composites were compared to untreated and treated DPF. Hybrid composites of 30% date palm and 70% kenaf were characterized by tensile, impact, physical, water absorption, and thickness swelling. The highest tensile strength recorded (26.45 MPa) and modulus among both untreated and treated hybrid composites (4.54 GPa) [34]. The effects that the DPFDPF density, diameter size, and content had on the mechanical and physical properties of a DPF bio-composite that was reinforced with polylactic acid [35]. The volumetric stability test may not indicate performance since wood’s dimensional stability varies significantly with the grain direction. In service, fluctuations in dimensions in a one-grain direction are typical of principal importance. Natural fibers, including those from date palms and wood chips, were tested for their impact on soil brick samples’ mechanical and physical qualities [36,37]. For example, Sargent [38] found that a change in grain orientation of up to 30 degrees resulted in a decline in ASE from 70 to 53%. Sections of specimens may be measured using calipers. Oven-dry volume may be measured using water displacement if the specimens are dry. Dynamic and free vibration analysis can provide valuable insights into the natural frequencies, mode shapes, damping ratios, and other dynamic characteristics of scrimber wood samples, which can help in predicting their behavior under different loading conditions. The failure modes, ultimate load, and cross-section stiffness of the reinforced bamboo scrimber composite beams were significantly correlated to the diameter of reinforcement as well as the heat treatment of bamboo bundle [39]. However, further research is needed to understand the dynamic behavior of Scrimber wood and its response to different loading conditions. Finite element analysis has been used to analyze the strength and serviceability of natural bamboo and bamboo scrimber [40,41]. Similarly, finite element analysis can be used to investigate the dynamic and free vibration behavior of scrimber wood samples [42].

The manufacturing of palm frond and stalk scrimber wood needs to be developed and innovated, and their mechanical properties with natural and industrial wood products need to be tested and compared. In Addition, the study aims to conduct mechanical tests and dynamic free vibration analysis on diverse specimens to gain insights into their natural frequencies, mode shapes, damping ratios, and other dynamic characteristics. This information can predict the performance of scrimber wood structures under diverse loading conditions. This research has the potential to significantly contribute to the wood science and engineering field. By developing new and improved methods for manufacturing the scrimber wood from sustainable resources, the study can help reduce the wood industry’s environmental impact. In addition, by better understanding the mechanical and dynamic behavior of the scrimber wood, the study can help to improve the design and performance of scrimber wood structures.

2 Materials and fabrication process

The date palm fronds were obtained from a farm site in Saudi Arabia; hence, it is the second largest date producer in the world. Before beginning the production process, the unneeded moisture was removed by cutting the used palm fronds and allowing them to dry in an open, dry location exposed to sunshine for several months. Following the drying phase, the frond leaves were removed from the stalk and prepared for the subsequent processing stage by being cut into segments that were each 50 cm long. Following that, the stalk segments were fed through the scrim rollers of a pressing machine, which caused the body of the stalk to separate into strips. After that, the split strips were collected and categorized according to their respective thicknesses. The thick strips were divided further by either splitting them by hand or manually running them through the pressing machine again. The resultant tiny strips had diameters ranging from 0.25 to 1.8 mm. They were impregnated with a polyvinyl acetate resin before being set down in a U-channel JIS400 steel mold with dimensions of 150 cm × 75 cm × 50 cm. The mold was compressed to a pressure of four bars using a hydraulic press. At the same time, it was covered with a flat bar A36 with the following dimensions of 10 cm × 75 cm × 50 cm. Figure 1a–c shows this process. Manual clamps maintained the applied compression force of the mold during the curing phase of the resin, which occurred at room temperature of 21–220°C and humidity of (55–60%). After 2 weeks, the scrim frond panel was removed from the mold and placed in a dry location with the same circumstances for an additional 2 weeks so that it could finish drying. After the panel had fully cured, its measured density was found to be 0.707 g/cm³, and it was cut and prepared into samples with standard dimensions for tensile and flexural testing, as shown in Figure 2a and b. An optical microscope was used to examine the cross-sectional microstructure with 150× magnification to investigate the bonding between the fronds’ strips and the resin. The nonuniform distribution of the strips and the variation in the diameters of the strips before the pressing step might be to blame for some resin and strip-rich areas, as shown in Figure 3, in various locations across the panel’s cross section. This is illustrated by the fact that these locations are scattered across the panel. In addition, some air-pocket spaces were seen between the strips, which may have been caused by the high viscosity of the resin and/or the low compressing stress. The researchers saw these voids.

Figure 1

Samples from left to right are plywood, MDF, frond scrimber, and pine wood. (a) Flexural test samples and (b) tensile test samples.

Figure 2

(a) Impregnated fronds, (b) compressed fronds inside the mold, and (c) fronds panel after full curing.

Figure 3

Microstructure of the fabricated samples: (a) area rich with resin and (b) area rich with strips of palm fiber.

3 Dynamic and vibration test setup

It is important to conduct dynamic and free vibration analysis on various samples to ensure the optimal design and performance of structures made from the scrimber wood. In this study, temporal deterioration was quantified using an accelerometer, namely, the B&K model 4507 B, securely attached to the detached appendage of the specimens under examination. The specimen was excited using an impact hammer (B&K model 8206, Brüel & Kjaer, Naerum, Denmark), as shown in Figure 4, the setup test. The vibration response was measured and analyzed using the pulse data analyzer (B&K module 3160-A-4/2 Brüel & Kjaer, Naerum, Denmark) in accordance with the studies by Moustafa [43,44]. The research employed a test rig configuration to conduct the experimental investigation. The frequency response function [45], damping ratio, and fundamental frequencies were computed using ME Scope’s modal analysis software. The experiment on free vibration was performed and repeated on five occasions to ensure accuracy in the obtained measurements.

Figure 4

Free vibration impact test setup (a) unzoomed view of the sample (b) zoomed view of the sample showing the accelerometer mounting method.

4 Mechanical flexural and tensile tests

The mechanical flexural and tensile properties of the palm frond and palm stalk scrimber wood samples were evaluated using the SANS machine, a universal testing machine (UTM) manufactured by SANS Testing Equipment. It is a versatile machine that can be used to perform a wide range of mechanical tests on materials, including tensile, compression, flexural, and shear tests. The flexural test was performed in accordance with the ASTM D790 standard, while the tensile test was performed in accordance with the ASTM D143 standard.

The samples were loaded with a three-point bending fixture for the flexural test. The load was applied at the center of the span, and the deflection was measured at the center of the span. The flexural modulus (modulus of elasticity (MOE)) and the modulus of rupture (MOR) were calculated from the load–deflection curves. The samples were gripped at their ends and loaded in tension for the tensile test. The load–elongation curve was recorded, and the tensile modulus (E) and the UTS were calculated.

The UTM used in this study is a versatile machine that can be used to perform a wide range of mechanical tests on materials. The UTM is equipped with a load cell to measure the applied load and a displacement transducer to measure the deformation of the sample. The UTM can be controlled using a computer to apply various loading conditions, such as constant load, constant displacement, and cyclic loading. The UTM used in this study is a high-precision machine capable of measuring loads and displacements with high accuracy. The UTM is also equipped with a variety of safety features to protect the operator and the sample.

5 Results and discussions

5.1 Flexural Test

Figure 5 shows the typical flexural test of some selected samples, such as pine wood, frond scrimber, MDF, Oakwood, etc. To observe which material has the most prominent resistance to the bending moment and yield strength, we need two different types of tests: One is the three-point bending test, which is commonly used in civil engineering, and the other one is the tensile test, which is common for metallurgy testing purposes [46]. The test was performed as per ASTM D1037, and the results are plotted in Figure 6. The wood types used in the tests are as follows: (A), plywood; (B), MDF; (C), frond scrimber; (D), oak; (E), pine wood; (F), bamboo. The bamboo sample was taken from a ready-made Ikea disk, ÖVRARYD. Cross-laminating bamboo strips prepared the disk. However, the test sample was taken from one layer of strips and aligned longitudinally with the direction of the tensile force on the test machine. Flexural properties (MOR and MOE) were used to characterize the investigated samples. According to the results, we can conclude that Frond Scrimber has the greatest resistance to the bending moment among the aforementioned samples. The maximum deflection is 28.9 and 39.7% greater than that of Oak wood and bamboo wood, respectively. The frond scrimber has 52 MPa in MOR, higher than Polywood and MDF wood. On the other hand, the highest MOR is the Oak wood which reaches 106 MPa. Moreover, both pinewood and bamboo have a flexural strength of around 70 MPa. This suggests that introducing a composite material made of palm fronds can increase the rigidity of the load-bearing structures and consequently improve the structural stability of houses and other buildings; this result is consistent with the study by Wei et al. [47]. As shown in Figure 6, hardwood samples D and E fractured as expected at the highest loading by recording 690.8 and 578.8 N, respectively. The sample F fractured below the load values of samples D and E by 24.8 and 10.3% at 519.2 N, and they all showed a sudden fracture after reaching their maximum loads. The maximum deflection for samples D–F is between 6.25 and 7.5 mm. Sample B fractured at the least load at 230.7 N and had a maximum deflection of 6.93 mm due to the soft nature of its structure. The other softwood sample A showed good flexural strength and fractured by 33.6% more than sample B at a maximum load of 347.4 N and with less deflection by 33.3%. However, as industrial wood panels, samples A and B did not reach the flexural strength of the other industrial wood samples C and F. The flexural test results showed that frond scrimber has the greatest resistance to the bending moment among the six types of wood tested. It also has the highest maximum deflection, suggesting that it is a more flexible material than oak or bamboo. The hardwood samples (oak and pine) fractured at the highest loads, followed by the bamboo sample. The plywood and MDF samples fractured at the lowest loads. These results suggest that frond scrimber is a promising new material for use in load-bearing structures. It is stronger and stiffer than plywood and MDF and more flexible than oak and bamboo. This could lead to more sustainable construction practices and improved structural stability of houses and other buildings. Sample C showed an outstanding flexural performance (pseudo-ductility) with its delayed fracture by recording the highest deflection before fracture at 10.55 mm, which might be due to the fibrous structures of sample C, as shown in Figure 7.

Figure 5

Typical flexural test of some selected samples: (a) pine wood, (b) frond scrimber, (c) MDF, and (d) oak wood.

Figure 6

Flexural test: (a) samples behavior against load, (b) three-point bending test setup before fracture, and (c) three-point bending test setup after fracture.

Figure 7

Maximum deflection in the flexural test of the investigated samples.

This delayed fracture can also be employed in structures where catastrophic failures are monitored to allow maintenance interference before failures. Moreover, sample C flexural strength was in between the high fracture loads of hardwood samples and the low fracture loads as in the other industrial wood samples A and B, except for sample F, as shown in Figure 8. Sample C recorded less flexural strength than sample F by 20.7% at 411.96 N. Regarding P _pl, samples D, E, and F with high flexural stiffness recorded nearly the same values (445, 435, and 435 N, respectively), and this is expected due to their hard-natural properties. On the other hand, industrial samples A and B recorded the least P _pl (244.2 and 135.5 N, respectively) due to their soft nature. In contrast to the behavior of sample C in tensile test results, sample C followed the performance of the low stiffness samples with P _pl not more than 271.1 N. The MOR is a measurement that determines how strong a specimen is just before it ruptures. Figure 9 shows different behaviors of the modulus of rapture investigated from the bending test. Thus, the results showed higher rapture modulus of samples D (Oak), E (pine wood), and F (Bamboo), while samples A (plywood) and B (MDF) obtained lower rupture modulus. Sample C (frond scrimber) showed a moderated value of 48.53 ± 1.8 MPa. Eqs. (1) and (2) are used to determine the MOR, apparent MOE, and work to maximum load for each specimen according to ASTM D1037 [48,49]. Here, b is the width of the specimen measured in the dry condition (mm); d is the thickness of the specimen measured in dry condition (mm); L is the length of span (mm); E is the apparent MOE; ∆P⁄∆y is the slope of the straight line portion of the load–deflection curve; P _max is the maximum load (N); and R _b is the MOR.

(1) R b = 3 P max L 2 b d 3 ,

(2) E = L 3 ∆ P 4 b d 3 ∆ y .

Figure 8

Maximum load in the flexural test of the investigated samples.

Figure 9

(a) The MOR and (b) the apparent MOE calculated from the flexure test.

5.2 Tensile properties

The industrial wood sample A was excluded from the tensile along the fibers test experimental results because they did not resist the clamping pressure applied by the testing machine’s grips and failed prematurely. The other samples were tested successfully as per ASTM D1037, and their results of the applied tensile load against the machine’s head displacement are plotted in Figure 10. According to the data shown in Table 1, samples B and F had the worst performance by fracturing at a temperature of 2.172 and 5.225 kN, respectively. Sample B, on the other hand, had a less stiff performance than sample F and shattered at a displacement of 53.8% greater. This more flexible behavior might be desired in some applications, particularly those in which catastrophic failures significantly contribute.

Figure 10

(a) Stress–strain curve of the investigated samples and (b) typical tensile test of the frond scrimber sample.

Table 1

Tensile test results

Sample	P max (N)	Disp. (max) (mm)	Young’s modulus (GPa)
E	11,956	0.75	16.79
D	18,076	1.39	13.99
C	12,062	1.12	12.84
F	5,225	0.49	11.64
B	2,172	1.06	3.05

On the other hand, sample D fractured at 18.076 kN, nearly 33% more than the second and third-highest samples C and E. Despite sample E being stiffer than sample C, samples C and E showed more stiff behavior when compared to samples B and F, and they fractured merely at the same loading rate (12,062 and 11,956 N, respectively). Compared to the other industrial wood, sample C fractured 82 and 57% more than samples B and F, respectively. The max displacement of sample C is about 33% greater than the fracture displacement of sample E. Furthermore, the load–displacement curve of sample C includes distinct linear and nonlinear components; hence, as the load increases, the sample will demonstrate stiff-liner performance until it reaches a load point when the sample begins to yield and the curve changes to nonlinear till a fracture occurs. Hence, sample C might mitigate the catastrophic failure experienced in hardwood sample E. This sample C performance might be due to its fibrous structure, which effectively provided samples with high fracture points as in hardwood and protracted maximum displacement in some softwood. The mechanical properties of the scrimber wood produced from date palm fronds have ultimate tensile stress (UCS) of 64.7 MPa, and an MOE of 12.84 GPa (Table 1). The mechanical properties of scrimber wood generated from date palm fronds are comparable to previous studies on similar materials. The values of the mechanical properties reported for the scrimber wood in this study are higher than those reported in the study by Hu et al. [50]. UCS is the maximum strain that a material can withstand before it breaks. Palm wood is a type of hardwood that can withstand high tensile stresses. The UTS of oak wood is 86.5 MPa. This is much higher than the tensile strength of most other studied wood types, such as polywood, MDF, and frond scrimber wood (Figure 11). Due to the superior strength of palm wood, it is used in many construction applications, including building and furniture making. The frond scrimber wood has a UCS of 62.8 MPa; hence, this value is less than oak wood by 27.3%. The results also showed that frond scrimber wood has a fibrous structure that effectively provides samples with high fracture points and protracted maximum displacement. This suggests that frond scrimber wood may be able to mitigate the catastrophic failure experienced in hardwood samples. Overall, the results of this study suggest that frond scrimber wood is a promising new material for use in a variety of applications, including construction and furniture making. However, the values of the mechanical properties reported for the scrimber wood in this study are higher than that reported in one previous study. This suggests that there may be some variability in the mechanical properties of the scrimber wood, depending on the specific manufacturing process used.

Figure 11

Ultimate tensile stress.

5.3 Water absorption and dimensional stability

The tests were performed per the procedures described in the Chinese National Standard for bamboo scrimber and bamboo scrimber flooring (GB/T30364-2013). Samples were cut into 50 mm × 50 mm × 15 mm sizes, and two samples of each wood type except types C and E were 3 and 1, respectively. Samples were immersed in boiling water for 4 h and then dried in a ventilating oven for 20+ h at 60°C. The process was repeated before taking the measurements and letting samples cool down at room temperature.

Only the samples of four wood types were measured: wood types C–F. Samples of wood types A and B were totally dissolved in the first round of boiling water. Samples of wood type C were dented in their panels’ cross sections due to the effect of water, as shown in Figure 12. No such effect was noticed in the hardwood samples except for a little dent in sample E. Strips of sample C were bonded together in contrast to sample E, where the bamboo strips disengaged due to the wetting and drying process. The percentages of water absorption (A), thickness swelling wet and dry T _wet and T _dry, and width swelling wet and dry W _wet and W _dry were calculated as illustrated in Table 2.

Figure 12

Dent in the frond scrimber samples.

Table 2

The percentages of water absorption, T _wet and T _dry, with swelling wet and dry W _wet and W _dry

Sample	A (%)	T wet (%)	T dry (%)	W wet (%)	W dry (%)
F	105.88	4.06	−9.25	2.36	−0.80
E	84.87	1.94	−4.48	3.56	−1.27
C	71.37	25.97	23.8	4.66	−1.25
D	38.54	10.73	−1.29	3.27	0.84

5.4 Dynamic characterization

Scrimber wood is a novel composite material that has recently gained attention due to its excellent mechanical properties and potential applications in structural engineering. To fully understand and utilize scrimber wood in practical engineering, it is essential to conduct dynamic characterization studies. Dynamic characterization refers to the process of acquiring and analyzing data related to the dynamic behavior of a material, including its natural frequencies, damping ratios, and mode shapes. One method for dynamic characterization of scrimber wood is free impact vibration analysis. This technique involves applying a force impulse to the material, which generates free vibrations that can be detected and measured using accelerometers. The resulting data can then be used to calculate the material’s natural frequencies and damping ratios, which provide insights into its dynamic behavior. The use of different types of wood can greatly affect the frequency and damping ratio characteristics of structures. In a study on the effect of types of wood (scrimber wood, pine wood, MDF, bamboo, and oak wood) on frequency and damping ratio characteristics, it was found that each type of wood has its own unique properties that can impact the behavior of the structure. Figure 13 depicts the time and frequency domains of the free impact vibration test. All the samples under investigation exhibit a high damping capacity, which can be attributed to their wooden composition.

Figure 13

Vibration response of the investigated samples: (a) time domain and (b) frequency response.

In Figure 13a, it was observed that both oak and MDF wood samples exhibited a fast decay time in the time domain. On the other hand, Figure 13b illustrates the fundamental frequency or the first mode natural frequency in the corresponding frequency domain. The time domain plot shows the samples’ vibration response as a time function. The plot shows that all the samples exhibit a high damping capacity, meaning the vibrations decay quickly over time. This is due to the wooden composition of the samples. The time domain plot also shows that the oak and MDF wood samples have the fastest decay times. This means that the vibrations in these samples decay more quickly than in the other samples. This is likely since oak and MDF wood are denser and stiffer than the other types of wood tested. The frequency domain plot shows the vibration response of the samples as a function of frequency. The plot shows each sample’s fundamental frequency or first mode natural frequency. The fundamental frequency is the lowest frequency at which the sample will vibrate freely. The frequency domain plot shows that the oak wood sample has the highest fundamental frequency. This means that the oak wood sample is stiffer than the other types of wood tested. The bamboo sample has the second-highest fundamental frequency.

Figure 14 depicts the dynamic properties of the wood samples under study. It can be observed that the frond scrimber wood exhibits favorable properties when compared to oak and MDF woods. Figure 14a illustrates that bamboo wood, pine wood, and scrimber wood exhibited the highest damping ratio, whereas MDF and oak wood demonstrated the lowest damping ratio. Conversely, the maximum resonant frequency at the first mode shape was observed for oakwood, while the minimum resonant frequency was recorded for bamboo wood, as shown in Figure 14b. Furthermore, the study found that the properties of wood are closely related to the impact of sound insulation performance of structures. Overall, the type of wood used in a structure can significantly impact its frequency and damping ratio characteristics. It is important to consider the properties of different types of wood when designing or evaluating structures to optimize their performance. It should be noted, however, that the study only investigated a limited number of wood types and may not represent all types of wood. Therefore, further research is necessary to fully understand the impact of wood types on frequency and damping ratio characteristics. According to a study on the effect of types of wood on frequency and damping ratio characteristics, each type of wood exhibits unique properties that can affect the behavior of a structure. The study found that all wood samples had a high damping capacity, but oak and MDF woods exhibited a fast decay time in the time domain, while frond scrimber wood exhibited the most favorable properties in terms of damping and resonant frequency characteristics.

Figure 14

Dynamic characteristics: (a) damping ratio and (b) first mode resonant frequency.

6 Conclusion

This article gives promising results in using palm fronds in industrial wood. In the future, we would like to extend our study to examining panels under a vacuum to reduce the voids in the internal structure of specimens. This might improve the material’s mechanical properties and reduce its water absorption.

• The quality of the manufactured frond panel was good, reflected in the panels’ tensile and flexural performance. However, the performance might also be enhanced by improving the manufacturing steps, especially in splitting more homogenous and uniform strips and using less viscous resin to mitigate the presence of voids within the panel’s internal structures.

• The frond panel performed better than most other industrial wood in both flexural and tensile tests due to its unique structure, emulating the natural wood’s fibrous structure.

• The flexural pseudo-ductility performance of the fronds panels serves the applications where structural health monitoring systems are required.

• The fronds panel showed good dimensional stability compared to the other types of wood used in this study. The plywood and MDF wood were totally dissolved in the first round of boiling water. Strips of the frond scriber were bonded together, where bamboo strips disengaged due to the wetting and drying processes.

• The selection of wood type and its inherent properties, including natural vibration frequency, damping ratio, and mode of vibration, are crucial factors that require careful consideration in constructing a structure. Notably, the viscoelastic properties of various wood species may differ and could be influenced by factors such as temperature and the corresponding moisture level.