Mechanical Properties Of Bamboo Research Articles

Gradient Variation and Correlation Analysis of Physical and Mechanical Properties of Moso Bamboo (Phyllostachys edulis).

This study aimed to investigate the gradient properties of bamboo at the microscopic level and provide a basis for improving the utilization rate of bamboo. Using moso bamboo (Phyllostachys edulis (Carrière) J. Houz.) as a research subject, the variation of vascular bundle area percentage, chemical content, relative crystallinity (CR), mechanical properties of different bamboo slivers, and correlation between those parameters were analyzed. From the bamboo green layer (BGL) to the bamboo yellow layer (BYL), the distribution of vascular bundles changed from dense to sparse. Cellulose and lignin mass content decreased gently, and hemicellulose mass content showed gradual increases. The CR showed an order of bamboo middle layer (BML) > BGL > BYL. The tensile modulus of elasticity, tensile strength, bending modulus of elasticity, and bending strength decreased from BGL to BYL. The order of influence degree on mechanical properties of moso bamboo was vascular bundle area, hemicellulose content, lignin mass content, density, and CR, and these factors correlated with mechanical properties at a significant level (p < 0.05). Vascular bundle area had a decisive effect on the mechanical properties of bamboo. The vascular bundle area and density were linearly correlated with mechanical properties, while the lignin mass content and CR were curve-linearly correlated with mechanical properties.

Effect of thermal modification on axial compression properties and hardness of laminated bamboo

Vacuum thermal modification is an environmentally friendly method to improve the durability and reduce insect infestation of bamboo, which has the advantages of preventing deformation, preventing oxidation of the bamboo surface, and uniformity of thermal conductivity compared to previous studies that used mediums such as nitrogen, air, or oil for heating. This study thermally modified laminated bamboo materials for 1 to 5 h under vacuum conditions ranging from 170 to 230 °C and evaluated their microstructure, surface hardness, water absorption, and axial compression mechanical properties. The results showed that compared with untreated laminated bamboo timber, the colour gradually deepened as the temperature and time of heat treatment increased, while the equilibrium moisture content of heat-treated laminated bamboo timber was reduced by about 4–27% and the density by about 11–18%. This phenomenon indicates that the cell walls of laminated bamboo become denser with increasing temperature, which leads to a significant decrease in the hygroscopicity of laminated bamboo. The dimensional stability of the material was improved. Regarding the macroscopic axial compression test, the results showed that the thermal modification treatment significantly increased the axial compression strength of laminated bamboo, and this improvement in mechanical properties was inversely related to the heat treatment temperature. In addition, through the nanoindentation test, we found that the laminated bamboo's surface hardness and modulus of elasticity showed an inflexion point when the treatment temperature reached 210 °C, indicating that the material properties changed significantly in this temperature range. Investigating the response mechanism between the temperature and time of vacuum thermal heat treatment and the mechanical properties of bamboo will contribute to the development or optimization of the thermal modification process, leading to materials with excellent properties and broadening the application areas.

The Application of Bamboo in the Railway Industry: A Sustainable Solution for Track Construction

The railway industry has shown a strong interest in utilizing sustainable materials, including recycled materials and composites, in construction. Bamboo, as a highly renewable natural resource, has been proposed as a construction material for the railway industry. This material offers several advantages, such as high strength and durability, sustainability, low embodied energy, and ease of handling. It has been used in various construction materials like plywood, scrimber, laminates, and fibers. This paper aims to review the application of bamboo as a material in the railway industry and provide suggestions for its future use as railway sleepers. The mechanical properties of bamboo and its desirable features for sleeper construction, such as versatility, durability, low embodied energy and carbon footprint, lightweight, and ease of handling, are discussed. Bamboo-based products like plywood and scrimber can offer higher mechanical properties compared to traditional timber sleepers. Moreover, due to its rapid growth rate, bamboo is considered an environmentally friendly material. However, there are certain factors that limit the widespread deployment of bamboo in the railway industry. For instance, the lightweight nature of bamboo can reduce the lateral resistance of sleepers. Additionally, long-term performance studies and its performance in regions with varying weather conditions need to be further investigated. This review paper aims to promote the increased utilization of bamboo in the railway industry, contributing to the development of sustainable railway tracks. By considering the mechanical properties and advantageous characteristics of bamboo, it is possible to explore its potential as a viable and eco-friendly material for railway sleepers.

Durability and strength sustainability assessment of rockwool-bamboo reinforced ceiling boards

It is increasingly important to explore means of reducing deforestation in our environment by sourcing alternatives for timber in the forest. Bamboo (Bambusa vulgaris) is known for its strength and flexibility, which makes it a popular material for construction, furniture, and other uses that are still being explored. This paper evaluated the use of bamboo for the design of ceiling boards based on the physical and mechanical properties of bamboo. We explored the use of bamboo powder, bamboo fibre, and bamboo sticks that are usually discarded during construction activities, using urea-formaldehyde as a binding agent. The bamboo ceiling boards were tested for their physical (water absorption, thickness swelling, and density) and mechanical (modulus of rupture and modulus of elasticity) properties. Water absorption ranged from 41.9% to 86.4% after 2 h immersion in water and from 41.9% to 97.6% after 24hrs immersion. The modulus of rupture was 78.915 N/mm2 and the highest density was 0.424 g/cm3. Given these results, bamboo is a suitable material for the production of ceiling boards.

The unique flexibility feature of bamboo: Cantilever-beam loading form the coupling bending-shear effects

Bamboo's remarkable attribute of flexibility has earned it widespread recognition, positioning it as an exemplary material for mimicking biological structures in advanced engineering construction. While the tension, compression, bending, shear, and torsion properties of bamboo have been extensively documented, its response under combined loads remains a topic that warrants comprehensive investigation. Filling this knowledge gap, the present study employs the cantilever-beam principle as a methodological framework to scrutinize the fracture mechanism and mechanical properties of bamboo under the coupling effect of bending-shear. The obtained results reveal a linear decrease in the bending moment from the fixed support to the free end of the strip, while the shear force maintains a constant distribution along the strip's length. Within a specific segment of the strip, the bending stress exhibits a linear increase with the distance from the neutral axis, whereas the shear stress manifests a parabolic variation above or below the neutral axis. During the plastic stage, simultaneous transverse and radial fractures occur, effectively dissipating crack energy through interfacial debonding, fiber sliding, and fiber bridging mechanisms. The presence of stepwise deflection between adjacent internodes allows for substantial overall angular deflection of the bamboo culm without incurring damage. Furthermore, the mechanical properties of the strips demonstrate a positive linear correlation with both the fiber volume fraction and the density of vascular bundles. A notable achievement of this study is the establishment of a numerical structure-activity relationship, elucidating the bending-shear coupling performance. This relationship serves to clarify the fracture toughness exhibited by bamboo and provides a valuable reference for performance testing and the formulation of standardized protocols in the realm of biomimetic material production.

A Literature Review On the Use of Bamboo as A Truss Member and Fiber-Reinforced Polymer as A Truss Jointing Material

A truss is a structure that has a rigid configuration formed by an assembly of straight members connected by pins. Many roofing systems use trusses, but the wide variety of truss configurations in architecture is an advantage to creating vast arrays of aesthetics in buildings. Steel, mainly plain carbon steel designated A36, is the most used material for truss members and joint connectors. However, these members are both heavy and non-sustainable, soseveral kinds of literature recommend studying the potential of using lightweight and sustainable alternatives. This review focuses on using bamboo in truss and the potential of fiber-reinforced composite as a truss joint connector. Bamboo culms and glued-laminated bamboo (glubam) are the two types of bamboo commonly used in truss fabrication based on the review. Bamboo culms from Dendrocalamus asper exhibit a tensile strength of 340 MPa, while the glubam made of Yushania alpina has 364 MPa. Other mechanical properties of bamboo necessary for the truss analysis are not yet clearly defined, although studies used ASTM D143-09 to determine several mechanical properties of bamboo or glubam. Fiber-reinforced composite can exhibit an enormous array of varieties and still demonstrate a strength close to or even higher than steel. It is lightweight and can reach a tensile strength of 700 MPa. The researcher recommends synthesizing bamboo or glubam as truss members and fiber-reinforced composite as truss joint connectors.

Effects of Heat Treatment under Different Pressures on the Properties of Bamboo.

To optimize the bamboo heat treatment process, the corresponding evolution rules under various heat treatment conditions must be determined. When the heat treatment time and temperature remained constant, the effects of different heat treatment pressures on the equilibrium moisture content, dimensional stability, mechanical properties, and chemical composition of bamboo were systematically investigated. In this experiment, bamboo without heat treatment was used as the control group. The experimental findings demonstrate the following: (1) The equilibrium moisture content of heat-treated bamboo gradually decreases with increasing treatment pressure. When the heat treatment pressure was set at 0.1, 0.15, 0.2, and 0.25 MPa, the bamboo's equilibrium water content decreased to 12.1%, 11.7%, 9.9%, and 8.6%, respectively, while that of the control group was 13.8%. (2) The dimensional stability of bamboo was enhanced with increasing heat treatment pressure. At pressures of 0.1, 0.15, 0.2, and 0.25 MPa, the radial air-dry shrinkage rates of the heat-treated bamboo decreased to 3.4%, 3.4%, 2.6%, and 2.3%, respectively, while the tangential air-dry shrinkage rates reduced to 5.6%, 5.1%, 3.3%, and 3.0%. In comparison, the radial and tangential air-dry shrinkage rates of the control group were measured as 3.6% and 5.8%, respectively. Similarly, the radial and tangential full-dry shrinkage of bamboo exhibited a similar trend. (3) With the increase in heat treatment pressure, the bending strength and longitudinal compressive strength of bamboo exhibited an initial rise followed by a decline. When it was at heat treatment pressures of 0.1, 0.15, 0.2, and 0.25 MPa, the corresponding bending strengths of the heat-treated bamboo were measured as 41.2, 26.7, 22.4, and 20.4 MPa, respectively; while the longitudinal compressive strengths were recorded as 42.6, 38.1, 29.1, and 25.3 MPa. In comparison, the bending and longitudinal compressive strengths of the control group were measured as 39.8 and 38.5 MPa, respectively. It is evident that the optimal heat treatment pressure for bamboo is 0.1 MPa, resulting in a significant increase of 3.5% and 10.6% in bending strength and longitudinal compressive strength, respectively, compared to the control group. (4) Based on the FTIR and XRD patterns of bamboo samples, a range of physical and chemical transformations were observed during the heat treatment process, including cellulose adsorb water evaporation, hemicellulose and cellulose degradation, as well as acetyl group hydrolysis on the molecular chain of hemicellulose. These changes collectively impacted the physical and mechanical properties of bamboo.

Gradient changes in fiber bundle content and mechanical properties lead to asymmetric bending of bamboo

Natural biomaterial bamboo has excellent strength and toughness. The content of fiber bundles and the gradually increasing tensile strength of fiber bundles from the inside to the outside in the radial direction of the bamboo wall are the two main factors leading to significant differences in the fracture behavior and mechanical properties of bamboo under loading from different sides of bamboo strip. In this study, the flexural strength, toughness, and bending fracture energy of the bamboo loaded from the inside of the sample (Mode B) were found as 28%, 191%, and 174%, respectively, higher than those of the bamboo loaded from the outside of the sample (Mode A). The mechanical properties of samples loaded radially (Mode C) were higher than Mode A and lower than Mode B. The fracture process of the sample and the corresponding fracture morphology showed parenchyma fracture (matrix failure), fiber fracture, and interfacial debonding (fiber–fiber, fiber-parenchyma, parenchyma-parenchyma) occurring in all samples. Tearing of the cell wall, fiber debonding, fiber bridging, fiber pull-out, and crack deflection are the major fracture-toughening mechanisms of bamboo. This study reveals the relationship between the gradient changes in the mechanical properties and content of bamboo fiber bundles and the bending and fracturing behavior of bamboo, which provides theoretical basis and ideas for the development of new bamboo engineering materials, the bionic design of bamboo structures, and the structural optimization of fiber-reinforced composite materials.

Coupling Preparation of Reconstituted-Bamboo-Board and Xylooligosaccharide via Hydrothermal Desaccharification Catalyzed by Slight Solid Alkali

Low-temperature carbonization is usually used to decompose bamboo hemicellulose to improve anti-decay and anti-mildew properties of bamboo board. Since xylan extraction from bamboo can produce xylo-oligosaccharides, there is a good coupling point between bamboo desaccharification and xylo-oligosaccharide production. In this study, the solution of xylan in bamboo and the controllable degree of polymerization hydrolysis could be achieved by solid base catalytic hydrothermal desugar treatment as well as the mechanical properties of bamboo could be maintained. The yield of xylan was up to 16.8% by appropriate alkali-suppressed method. In addition, the color of the desugared bamboo board was lighter, which was applicable to a wide range. Compared with carbonized bamboo board, the key mechanical properties of desugared bamboo board were significantly improved by 2 to 4 times. Under the same conditions, the anti-decay and anti-mildew properties of d desugared bamboo board were better than those of carbonized bamboo board as well. In conclusion, this study demonstrated the feasibility of hydrothermal desaccharification coupling for the preparation of outdoor reconstituted-bamboo-board.

Microcapsules of chitosan-loaded luffa seed oil for improving the mold-resistance of bamboo

Mold infestation-induced degradation of quality and performance of bamboo remains a persistent and unresolved issue in the bamboo engineering industry. Herein, an effective strategy was proposed to prepare mold resistant bamboo by luffa seed oil (LSO) microcapsules impregnation method. First, microcapsules were prepared by ionic gelation method, with LSO as the core and chitosan as the shell. Second, the microwave-pretreated bamboo slices were vacuum impregnated with the microcapsules. Microcapsules exhibited good slow-release properties, with a maximum embedding ratio of 17.65% and an average particle size of less than 500 nm. Microcapsules got adsorbed, bonded to, or fused with the bamboo fiber cell wall, and they exhibited less effect on the moisture absorption ratio, moisture desorption ratio, and mechanical properties of bamboo. However, the microcapsule impregnation treatment led to significant improvement in the mold resistance of the bamboo slices, so that the infection level was still level 1 after 30 d of inoculation with mold. This strategy lays a strong foundation for further research on mold-resistant bamboo materials and encourages new applications in green engineering.

Physical and Mechanical Properties of Bamboo Fiber/Glass Fiber Mesh Reinforced Epoxy Resin Hybrid Composites: Effect of Fiber Stacking Sequence

ABSTRACT To further improve the preparation efficiency and properties of bamboo fiber reinforced polymer composites (BFRPs) fabricated by the vacuum-assisted resin transfer molding (VARTM) process. Here, the bamboo fiber/glass fiber mesh reinforced polymer hybrid composites (BGRPs) were fabricated by VARTM to determine the effects of three fiber stacking sequences (namely, GBBGBBG, BGBGBGB, and BBGGGBB; B: bamboo fiber, G: glass fiber mesh) on the physical and mechanical properties, as well as void characteristics of BGRPs (i.e. BGRP-1, BGRP-2, and BGRP-3). The results showed that the incorporation of glass fiber meshes could shorten the injection time of epoxy resin and improve the mechanical properties of BFRPs. BGRP-1 exhibited the lowest water absorption (1.31%) and the highest shear strength (15.55 MPa). Glass fiber meshes on the surface and bottom of BGRP-1, respectively, served as buffer layers to retard mechanical damage, so that BGRP-1 had the best drop hammer impact properties. BGRP-2 represented the highest flexural strength and flexural modulus of 92.22 MPa and 6.69 GPa, respectively. The mechanical properties of BGRP-3 were inferior to those of BGRP-1 and BGRP-2, and more voids were observed in the middle of BGRP-3 in micro-CT slices induced by inadequate epoxy resin impregnation on bamboo fibers.

Thermal treatment of bamboo with flame: influence on the mechanical characteristics

The mechanical properties of bamboo are susceptible to degradation due to both physical and biological agents. Among the non-chemical treatments, we studied the influence of a short-time heat treatment, using an LPG-gas torch, on the mechanical properties of a bamboo (Phyllostachys viridiglaucescens) growing in Italy. The response was very encouraging as we found no significant reduction in either elastic modulus or tensile, compressive and bending strength.Several samples were subject to tension, compression and bending tests to compare the responses of the treated and untreated culms. The average tensile elastic modulus was slightly greater for the untreated culms. The average tensile strength of the untreated culms was only slightly greater, and the differences can be assumed to be insignificant from a structural point of view. The average value of the treated culms compressive elastic modulus was slightly greater than that of the untreated ones. The compressive strength was essentially the same. The bending mechanical behaviour was barely influenced by the thermal treatment.A microscopic investigation (optical and electron microscopy) was undertaken to investigate the possible deterioration of the bamboo microstructure due to the heat treatment. No appreciable damage was detectable in the treated material.The proposed heat treatments can be considered as a reliable and sustainable protection practice for bamboo culms.

Evaluation of Physical Properties of Some Selected Bambusa Species of Manipur

Background: Bambusa is one of the three largest genera of bamboo found in India. Physical properties have direct influence on mechanical properties of bamboo. This study was conducted to investigate the physical properties viz. moisture content, specific gravity, water absorption and dimensional shrinkage of some selected Bambusa species of Manipur in order to find their suitability for various end uses. Methods: The culms were harvested at 30 cm above ground level. Each culm was divided into bottom, middle and top positions. Moisture content, specific gravity and dimensional shrinkage percentage were determined using Indian Standard Method IS 6874 (2008) while ASTM D 1034-72 method was used for water absorption test. Result: Moisture content and water absorption decreased with the increase in culm height whereas specific gravity increased from bottom towards the top portion in all selected eight Bambusa species. Dimensional shrinkage percentages exhibited an irregular pattern. Radial and tangential shrinkages were higher than longitudinal shrinkage. Analysis of variance of the physical properties among the Bambusa species exhibited significant variations at all height positions. B. kingiana is the most desirable among the selected Bambusa species due to comparatively higher specific gravity and low moisture content, water absorption capacity, dimensional shrinkage and T/R ratio

Effects of Accelerated Ageing by Humidity and Heat Cycles on the Quality of Bamboo.

The effect of humidity and heat environmental conditions on the durability of conventional bamboo materials is a pressing issue in the reserving phase of biomass materials. In this study, the relationship between the main physicochemical, pyrolytic, and mechanical properties of bamboo before and after ageing has been investigated. Exposure of engineered bamboo raw materials with moisture content up to 10% to alternating humidity and heat cycles (20 °C 98% RH-30 °C 64% RH-40 °C 30% RH) of ageing (HHT) causes degradation of the chemical polymer matrix. Byk Gardner 6840 color difference meter, X-ray diffraction, Fourier transform infrared spectroscopy (FTIR), compression intensity, thermogravimetric-infrared spectroscopy (TG-IR), and density changes are used to assess the quality of the material before and after ageing. No significant changes in the moisture content within the range of 6.12 ± 0.327 after two weeks of the engineered bamboo during wet thermal cyclic ageing were determined. However, there were significant differences in mass loss (7.75–9.93 g), cellulose crystallinity, chemical changes, compression strength, and pyrolytic properties. Differences in specimen colors were observed during 10 weeks of the accelerated humidity heat cycling ageing, and TCD variations ranged from 3.75 to 20.08 and from 0.25 and 3.24, respectively. Reduced cellulose crystallinity (36.459–22.638%), axial compressive strength (63.07–88.09 MPa), and modulus of rupture (2409–4286 MPa) were found during aging, whereas deformation and ductility properties were improved. Both natural and humidity heat ageing improve thermal stability and peak pyrolysis rates (0.739–0.931; 0.731–0.797). Humidity heat cyclic ageing will assist in the design and risk assessment of warehousing environments for industrial applications.

Pressure-Steam Heat Treatment-Enhanced Anti-Mildew Property of Arc-Shaped Bamboo Sheets.

Bamboo is one of the most promising biomass materials in the world. However, the poor anti-mildew property and poor dimensional stability limits its outdoor applications. Current scholars focus on the modification of bamboo through heat treatment. Arc-shaped bamboo sheets are new bamboo products for special decoration in daily life. In this paper, we reported pressure-steam heat treatment and explored the effect of pressure-steam on the micro-structure, crystallinity index, anti-mildew, chemical composition, physical properties, and mechanical properties of bamboo via X-ray diffractometer (XRD), scanning electron microscopy (SEM), Fourier-transform infrared (FTIR), wet chemistry method and nanoindentation (NI). Herein, saturated-steam heat treatment was applied for modified moso bamboo for enhancing the anti-mildew properties and mechanical properties of moso bamboo. Results showed that with the introduction of saturated steam, the content of hemicellulose and cellulose decreased, while the lignin-relative content increased significantly. The anti-mildew property of moso bamboo was enhanced due to the decomposition of polysaccharide. Last, the modulus of elasticity and hardness of treated moso bamboo cell walls were enhanced after saturated-steam heat treatment. For example, the MOE of the treated moso bamboo cell wall increased from 12.7 GPa to 15.7 GPa. This heat treatment strategy can enhance the anti-mildew property of moso bamboo and can gain more attention from entrepreneurs and scholars.

Chemical, Physical, and Mechanical Properties of Belangke Bamboo (Gigantochloa pruriens) and Its Application as a Reinforcing Material in Particleboard Manufacturing.

This study aimed to analyze the basic properties (chemical composition and physical and mechanical properties) of belangke bamboo (Gigantochloa pruriens) and its potential as a particleboard reinforcement material, aimed at increasing the mechanical properties of the boards. The chemical composition was determined by Fourier transform near infrared (NIR) analysis and X-ray diffraction (XRD) analysis. The physical and mechanical properties of bamboo were evaluated following the Japanese standard JIS A 5908 (2003) and the ISO 22157:2004 standard, respectively. The results showed that this bamboo had average lignin, holocellulose, and alpha-cellulose content of 29.78%, 65.13%, and 41.48%, respectively, with a degree of crystallinity of 33.54%. The physical properties of bamboo, including specific gravity, inner and outer diameter shrinkage, and linear shrinkage, were 0.59%, 2.18%, 2.26%, and 0.18%, respectively. Meanwhile, bamboo’s mechanical properties, including compressive strength, shear strength, and tensile strength, were 42.19 MPa, 7.63 MPa, and 163.8 MPa, respectively. Markedly, the addition of belangke bamboo strands as a reinforcing material (surface coating) in particleboards significantly improved the mechanical properties of the boards, increasing the modulus of elasticity (MOE) and bending strength (MOR) values of the fabricated composites by 16 and 3 times.

Effect of preservative treatment on physical and mechanical properties of bamboo (Gigantochloa scortechinii) strips

Using a vacuum pressure cylinder, Gigantochloa scortechinii was treated with boron and copper chrome boron (CCB) preservative at different concentrations of 2% and 3%. The treatability of untreated and treated bamboo, as well as its physical and mechanical properties, were investigated. Both preservatives showed a high level of penetration into the bamboo strips. Weight percent gain (WPG) and extent of retention of CCB-treated bamboo strips were higher than those of the boron-treated samples. Swelling and shrinkage were proportionately reduced with treatment, with a significant difference between radial and tangential dimensions. When compared to untreated bamboo, treated bamboo showed a greater reduction in radial swelling but a lower reduction in shrinkage. The mechanical properties of untreated and treated samples differed in modulus of elasticity (MOE) and compression. Untreated samples had the highest MOE of 26,100 N.mm-2, while boron and CCB had MOE values of 22,800 and 22,900 N.mm-2, respectively. Copper chrome boron samples had the highest compression value of 86.3 N.mm-2, while the boron and untreated samples had values of 84.0 and 78.3 N.mm-2, respectively.

An Overview on Physical and Mechanical Properties of Bamboo as a Natural Reinforcement in Concrete

Bamboo regained popularity as a reinforcement for concrete, especially in simple construction because of its high in tensile strength. Bamboo’s material that has a fast reproduction which increases its suitability to use as a sustainable source especially in construction works. However, when bio-based materials in general, and bamboo in particular, are expected to be used in construction, the sensitivity to moisture and their durability are usually questionable. Physical and mechanical properties bamboo should be improved by treated with chemical to prevent the bamboo from insects, pesticides and ensure the longevity of bamboo. Bamboo fibres are mainly used as a natural reinforcement in concrete that can minimize energy consumption, protect non-renewable natural resources, reduce pollution and maintain a healthy environment. Therefore, this study was to review and collect data for physical and mechanical properties of concrete containing bamboo as a natural reinforcement. The addition percentages of bamboo fibres 0.5%, 1.0%, 1.5%, 2.0% and 2.5%, used in the research were evaluated. Overall, the bamboo fibres as reinforced concrete for 1.0% to 1.5% are the best ratio of mix designation that have significant increase in compressive and tensile strength that tested and reviewed after 28 days of curing. Meanwhile, the density test for concrete is shown lower compared to the British Standard of steel as reinforced in concrete. The treated bamboo that used chemical treatment were improved the bonding strength and reduced water absorption more than 50% compared to the untreated bamboo. Form the review that have been done, bamboo as reinforces in concrete are suitable for lightweight construction building.

Investigation on Mechanical Properties of Bamboo and Coconut Fiber with Epoxy Hybrid Polymer Composite

The present study focused to improve material characteristics and quality in terms of the NaOH concentration for treating the coconut and bamboo fiber to enhance the mechanical properties of natural fiber polymer-based hybrid composites. The NaOH-treated fibers were washed thoroughly using distilled water and allowed to dry for 24 hours. Composition of each specimen, bamboo (B) and coconut (C) fiber with epoxy composite, was prepared by hand layup process as per the American Society for Testing and Materials (ASTM) standard. The proportionality of the material was carefully fulfilled according to the previous literature reports. The weight fraction of the composite material content was set to be 30% and 70% of epoxy (E) resin and isolated fibers. Three distinct criteria were used to calculate mechanical parameters such as tensile strength, flexural strength, and material hardness. It was found that the combination of 70% E with 30% BC of hybridized composite had a maximum tensile strength of 62.42 MPa, whereas the flexural strength and hardness of the other combinations, such as 70% E with 30% C and 70% E with 30% B, were observed to be 58 MPa and 185 HRC (Hardness Rockwell C), respectively.

Comparative Study on Clear Specimen Strength and Member Strength of Side-Pressure Laminated Bamboo

Side-pressure laminated bamboo (LB) made from heat-modified, fast-growing bamboo is introduced in this document. As a relatively new type of bamboo composite fabricated by bamboo strips, side-pressure LB has some favorable mechanical properties, such as thermal insulation, light mass, high strength, and earthquake resistance. To promote the application of side-pressure LB in structural engineering, according to the test standards for timber, the mechanical properties of bamboo, including tensile strength parallel to the grain, compressive strength parallel to the grain, bending strength and bending modulus, and shear strength parallel to the grain, were obtained by testing clear bamboo. Meanwhile, the bending and shear tests were performed on full-sized beams of side-pressure LB. Comparing the strength of clear bamboo and full-sized bamboo beams under bending and shear, explore the effect of size on bending and shear strength. The results demonstrate that the size effect has a significant influence on the bending strength, and the bending strength decreases clearly with the increase of the span of member; the shear strength is mainly affected by the shear area and decreases with the increase of the shear area. Based on the measured indicators of shear strength, a formula suitable for converting the shear strength of clear bamboo to full-sized bamboo beam is proposed. And the recommended design strengths of bamboo are given by using the limit state method, which provides a design basis for the engineering application of bamboo.