Bamboo Timber Research Articles

A preliminary study on bamboo–timber composite columns under axial compression

Bamboo–timber composite columns hold significant promise as bio-based structural elements. However, research in this area remains limited, especially concerning modern buckling analysis methods that incorporate bio-based constitutive models of engineered bamboo and timber materials. This study aims to address this gap by proposing a proof-of-concept analytical framework based on component-based strategy for buckling analysis, utilising piecewise bio-based material constitutive models as the guide rail for its strain-stage-based component split-up. Preliminary experimental validation was performed to evaluate the feasibility of using component-based analysis to estimate the overall buckling resistance of both composite and non-composite bamboo and timber columns. This initial study offers an alternative analytical approach for estimating the buckling resistance of bio-composite columns and establishes a set of conceptual guidelines and indicative parameters for the experimental design of future research.

Clean production of laminated bamboo timber and efficient utilization of bamboo

ABSTRACT To reduce the environmental impact, the environmental impact of the Laminated bamboo timber (LBT) line has been assessed using Life Cycle Assessment (LCA), and the environmental impacts of four scenarios has been compared in this article. The environmental impact can be effectively reduced if the bamboo residues is burned instead of lignite to provide steam for the LBT production line. Global warming potential (GWP-100) can be reduced by 21.81%, acidification potential (AP) by 51.73% and eutrophication potential (EP) by 57.18%. In addition, the utilization rate of bamboo can be increased by 29.07% and the economic benefit can be increased by 34.73%. When the bamboo shavings from the bamboo strip rough processing stage are used to produce bamboo barbecue charcoal (BBC), the GWP-100 of the LBT line is reduced by 17.49%. And the utilization rate of bamboo can be further increased by 30.90% and the economic benefit can be further increased by 12.47%. When the GWP-100 of the BBC production is added to the GWP-100 of the LBT production line, there is a slight increase of 5.06% in the total GWP-100. However, it doesn’t make much difference whether the bamboo strip roughing workshop is located next to the LBT production line.

Responses of Soil Carbon and Microbial Residues to Degradation in Moso Bamboo Forest.

Moso bamboo (Phyllostachys heterocycla cv. Pubescens) is known for its high capacity to sequester atmospheric carbon (C), which has a unique role to play in the fight against global warming. However, due to rising labor costs and falling bamboo prices, many Moso bamboo forests are shifting to an extensive management model without fertilization, resulting in gradual degradation of Moso bamboo forests. However, many Moso bamboo forests are being degraded due to rising labor costs and declining bamboo timber prices. To delineate the effect of degradation on soil microbial carbon sequestration, we instituted a rigorous analysis of Moso bamboo forests subjected to different degradation durations, namely: continuous management (CK), 5 years of degradation (D-5), and 10 years of degradation (D-10). Our inquiry encompassed soil strata at 0-20 cm and 20-40 cm, scrutinizing alterations in soil organic carbon(SOC), water-soluble carbon(WSOC), microbial carbon(MBC)and microbial residues. We discerned a positive correlation between degradation and augmented levels of SOC, WSOC, and MBC across both strata. Furthermore, degradation escalated concentrations of specific soil amino sugars and microbial residues. Intriguingly, extended degradation diminished the proportional contribution of microbial residuals to SOC, implying a possible decline in microbial activity longitudinally. These findings offer a detailed insight into microbial C processes within degraded bamboo ecosystems.

Experimental study on tensile properties of along the grain metal-plate-connected joints of laminated bamboo lumber

Utilizing various metal-plate-connected dimensions and angles, the performance of load parallel to grain metal-plate-connected joints of laminated bamboo timber was examined. A tensile test is used to determine the effects of the metal-plate connection's dimension and angle on the connection joints' ultimate load, ultimate displacement, initial stiffness, and anti-sliding stiffness. According to the findings, when there is a 60° angle between the main shaft direction of the metal plate and the load, the ultimate strength of the load parallel to grain connection is at its highest. The metal-plate-connected joints ultimate load capacity will be impacted by changes to both the metal plate and the width. The metal plate pull-out damage that results from an increase in metal plate length in the AA direction will cause the ultimate load to decrease, whereas an increase in metal plate width in the AE direction will cause the ultimate load brought on by the increase of metal plate width to decrease due to the appearance of the metal plate shear damage. Comparing the tensile characteristics of various connecting materials, it is discovered that laminated bamboo lumber materials have good connecting characteristics. The Foschi model was used to do a non-linear fitting of the test curve, and the fitting formula was then obtained.

Unveiling the intrinsic mechanism of photoprotection in bamboo under high light

The study aims to unveil the intrinsic photoprotection mechanism of bamboo under high light. Bamboo, a fast-growing and regenerative plant, exhibits a wide distribution in temperate, subtropical, and tropical regions. Bamboo frequently exposed to various environmental stresses, including excessive light, which can cause photoinhibition and even photooxidative damage to the photosynthetic apparatus. However, the characteristics and intrinsic mechanism of bamboo photoprotection are still unclear. The photosynthetic performance and photoprotective capacity of 20 bamboo species by the chlorophyll fluorescence parameters are investigated in this study. Based on the results of similar photosynthetic and photoprotective characteristics in diverse bamboo species, moso bamboo (Phyllostachys edulis) is selected as the representative bamboo species for further investigation. The light energy allocation in leaves of moso bamboo under different light intensities is analyzed to reveal its adaptability to light fluctuations in nature. Meanwhile, the expression levels of non-photochemical quenching (NPQ)-related genes in leaves of moso bamboo under high light is analyzed. The results demonstrate that the expression of NPQ-related genes is induced by high light, especially that of PsbSs and VDE is significant, indicating they play important roles in photoprotection. Furthermore, in-planta gene editing of PsbSs and VDE is conducted respectively. The sequencing results reveal that the mutation rates of edited PsbS1, PsbS2, and VDE were 12.48 %, 13.42 %, and 14.43 % respectively. As a result, the NPQ values with edited PsbSs, VDE, and both are all lower than those of control under high light, indicating that the photoprotective capacity of bamboo leaves is weakened after gene editing. These findings contribute to a deeper understanding of the photoprotection mechanism in bamboo and establish a foundation for breeding new germplasm with enhanced carbon fixation capacity and higher bamboo timber yield.

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.

Degradation reduces greenhouse gas emissions while weakening ecosystem carbon sequestration of Moso bamboo forests

Moso bamboo (Phyllostachys heterocycla cv. Pubescens) is well known for its high capacity to sequester atmospheric carbon, which has a unique role to play in combating global warming. Many Moso bamboo forests are gradually degrading due to rising labor costs and falling prices for bamboo timber. However, the mechanisms of carbon sequestration of Moso bamboo forest ecosystems in response to degradation are unclear. In this study, a space-for-time substitution approach was used to select Moso bamboo forest plots with the same origin and similar stand types, but different years of degradation, and four degradation sequences, continuous management (CK), 2 years of degradation (D-I), 6 years of degradation (D-II) and 10 years of degradation (D-III). A total of 16 survey sample plots were established based on the local management history files. After a 12-month monitoring, the response characteristics of soil greenhouse gases (GHG) emissions, vegetation, and soil organic carbon sequestration in different degradation sequences were evaluated to reveal the differences in the ecosystem carbon sequestration. The results indicated that under D-I, D-II, and D-III, the global warming potential (GWP) of soil GHG emissions decreased by 10.84 %, 17.75 %, and 31.02 %, while soil organic carbon (SOC) sequestration increased by 2.82 %, 18.11 %, and 4.68 %, and vegetation carbon sequestration decreased by 17.30 %, 33.49 %, and 44.76 %, respectively. In conclusion, compared to CK, the ecosystem carbon sequestration was reduced by 13.79 %, 22.42 %, and 30.31 %, respectively. This suggests that degradation reduces soil GHG emissions but weakens the ecosystem carbon sequestration capability. Therefore, in the background of global warming and the strategic goal of carbon neutrality, restorative management of degraded Moso bamboo forests is critically needed to improve the carbon sequestration potential of the ecosystem.

Mechanical behavior of laminated bamboo–timber composite columns under axial compression

Mechanical behavior of laminated bamboo–timber composite columns under axial compression

Phytic acid-based hybrid complexes for improving the interfacial property and mildew-resistance of heat-treated bamboo

Thermally glue-laminated bamboo timber has become the most promising woody resource in the world. However, the poor glued bonding property and poor anti-mild property limit its practical applications. Current scholars focus on crack-free, flattened bamboo boards and its application. Herein, inspired by the natural phosphoric acid complexes, Phytic Acid-based hybrid complexes were fabricated on the bamboo surfaces for improving its interfacial property and mildew resistance. SEM-EDS mapping results showed that the phytic acid-based hybrid complexes were successfully coated on the bamboo surface. The average penetration depth values (AP) and effective penetration depth values (EP) of heat-treated bamboo increased from 10.55 µm and 79.32 to 15.69 µm and 98.12 µm. A large amount of phytic acid penetrates into the bamboo cell-matrix and a large number of hydrophilic groups attach to the bamboo inner tissue during the impregnation process. Thus, the grafted long-chain groups in phytic acid cross-link with the crown energy groups in phenolic resin, thus increasing the AP of phenolic resin and improving the interfacial property. Additionally, the modified bamboo samples exhibited better anti-mildew properties than those of the control.

Designing a novel type of multifunctional bamboo surface based on an RGO/Ag coating

Super-hydrophobic and fire-retardant coatings have been applied to the bamboo surface. However, it remains a significant challenge to develop coating materials that perform multiple functions simultaneously. In this paper, a novel conductive bamboo timber (RGO@AgBT), coated with reduced graphene oxide (RGO) and silver nanoparticles, was fabricated via a hydrothermal process and a silver mirror reaction process. The RGO@AgBT composites had excellent photo-catalytic activity, meanwhile, the removal rate of rhodamine B (RhB), methylene blue (MB), and methyl orange (MO) after 60 min photo-degradation were 77.6 %, 88.8 %, and 78.4 %, respectively, superior to the raw bamboo timber (BT) and the bamboo timber coated with reduced graphene oxide (RGOBT). The RGO@AgBT samples showed excellent antibacterial performance against Escherichia coli and Staphylococcus aureus. Additionally, the RGO@AgBT samples exhibited improved thermal stability and fire-resistant property with a limiting oxygen index of 30.5 %. Finally, the future directions of multifunctional bamboo research and opportunities for electronic industry application are prospected.

Combinatorial design and flexural behavior of laminated bamboo–timber​ composite beams

The use of bio-based building materials can reduce the pressure on the environment. As bio-based materials, timber and bamboo can be combined to produce excellent building materials. In order to improve the flexural performance of timber beam, a new type of laminated bamboo–timber composite beam was proposed by introducing the material of bamboo scrimber, which has better mechanical properties. The flexural behavior of seven-layer composite beams composed of bamboo scrimber and Douglas fir were tested. Four-point bending tests and theoretical derivations were conducted to study the failure modes, load–displacement curves, and flexural performance of the composite beams and to establish a theoretical model to describe the flexural performance of the composite beams. The results showed that the composite beams exhibited three failure modes. The deformation capacity and stiffness of the bamboo–timber composite beams were improved. Compared with timber beams of the same size, the flexural stiffness and capacity of the composite beams were significantly increased by 33.7% and 31.9%, respectively. Finally, the theoretical calculation proposed to describe the flexural stiffness and capacity could accurately predict the experimental results.

Improved Wettability and Dimensional Stability of Bamboo Timber by Coating Graphene/Silica Composites

Bamboo timber (BT) is a kind of natural porous material, and usually bamboo cracking and deformation are caused by the change of humidity in the environment. Inspired by the natural structure of the shell, a multilayer structure was designed to fabricate a kind of graphene/silica composite coating on the BT surface. The multilayer bamboo composite (FAS-RGO@SiO2BT) was prepared by using the self-assembly process of nanospherical silica on graphene followed by hydrophobic modification. A possible formation mechanism of FAS-RGO@SiO2BT was discussed by X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray analysis, X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy. The FAS-RGO@SiO2BT has excellent hydrophobic properties for tea, orange juice, milk, coffee, blue ink, red wine, and green juice. Also, the FAS-RGO@ SiO2BT has an obvious hydrophobic effect on any of the various solutions with a pH of 1 to 14. In addition, after a 90-day immersion test, the water absorption rate of FAS-RGO@ SiO2BT is 9.7% and the thickness swelling rate is 0.5%. The wettability and dimensional stability of the FAS-RGO@SiO2BT are significantly improved compared to those of BT.

A regulatory network driving shoot lignification in rapidly growing bamboo.

Woody bamboo is environmentally friendly, abundant, and an alternative to conventional timber. Degree of lignification and lignin content and deposition affect timber properties. However, the lignification regulatory network in monocots is poorly understood. To elucidate the regulatory mechanism of lignification in moso bamboo (Phyllostachys edulis), we conducted integrated analyses using transcriptome, small RNA, and degradome sequencing followed by experimental verification. The lignification degree and lignin content increased with increased bamboo shoot height, whereas phenylalanine ammonia-lyase and Laccase activities first increased and then decreased with shoot growth. Moreover, we identified 11,504 differentially expressed genes (DEGs) in different portions of the 13th internodes of different height shoots; most DEGs associated with cell wall and lignin biosynthesis were upregulated, whereas some DEGs related to cell growth were downregulated. We identified a total of 1,502 miRNAs, of which 687 were differentially expressed. Additionally, in silico and degradome analyses indicated that 5,756 genes were targeted by 691 miRNAs. We constructed a regulatory network of lignification, including 11 miRNAs, 22 transcription factors, and 36 enzyme genes, in moso bamboo. Furthermore, PeLAC20 overexpression increased lignin content in transgenic Arabidopsis (Arabidopsis thaliana) plants. Finally, we proposed a reliable miRNA-mediated “MYB-PeLAC20” module for lignin monomer polymerization. Our findings provide definite insights into the genetic regulation of bamboo lignification. In addition to providing a platform for understanding related mechanisms in other monocots, these insights could be used to develop strategies to improve bamboo timber properties.

The complete chloroplast genome of a solid type of Phyllostachys nidularia (Bambusoideae: Poaceae), a species endemic to China

Phyllostachys nidularia (Bambusoideae: Poaceae), widely distributed in the Yangtze River Basin and various provinces (regions) in southern China, is one of the most important small and medium-sized bamboo species used in both bamboo shoots and timber. In the present study, we assembled a complete chloroplast genome of the economically important bamboo form Phyllostachys nidularia f. farcta H.R.Zhao & A.T.Liu using whole genome sequencing data previously reported. The complete chloroplast (cp) genome is 139,706 bp in length. A total of 129 unique genes were annotated, including 82 protein-coding, 39 tRNA, and eight rRNA genes. Phylogenetic analysis results supported that P. nidularia f. farcta was closely related to Phyllostachys reticulata. This work would help us better understand the evolution of the Phyllostachys cp genome.

Analysis of settlement on slab-on-ground in soil strengthened with dolken, mangrove, and bamboo timber

Shallow foundation and slab on ground that were built on soft clays might have some settlement because of the low bearing capacity. If the settlement that happened was a differential settlement, it can cause damage to the structure. There are many ways to fix the soil by improving the bearing capacity such as using wood pile. Wood pile is often used because it was easy to find, easy to use, and cheaper than using the pile made of concrete. There are many types of wood that can be used, for example dolken wood, mangrove, and bamboo. Those type of woods have different specification that effected the wood strength as a pile to improve the soil bearing capacity. The diameter and length of the wood also influence the pile effectiveness. All this factor can give a different result in reducing the settlement that happened on the soil.

Green synthesis of fluorescent graphene quantum dots and its application in selective curcumin detection

Herein, we present a facile low-cost and eco-friendly approach for conversion of bamboo timber waste (Bf) derived cellulose nanocrystals (Bf-CNCs) into strong blue luminescent graphene quantum dots (Bf-GQDs) by hydrothermal route. The various properties of synthesized Bf-GQDs were investigated using different spectroscopic techniques. The probable mechanism of Bf-GQDs formation from Bf-CNCs and the effect of pH, particle size on the fluorescent properties of Bf-GQDs also executed. Furthermore, Bf-GQDs were used for the detection of curcumin in an aqueous environment which is the major prerequisite of the present study. The Bf-GQDs showed remarkable photoluminescence (PL) quenching kinetics toward the curcumin (LOD 30.0 nM L−1) assessed by Stern-Volmer plot. The practicability of the method assessed using ginger rhizome juice, while the selectivity of the Bf-GQDs evaluated against different metal ions and different biochemicals. The proposed method will support to establish the strategies for the detection of biochemicals from the aqueous system.

Fabrication of Superhydrophobic Film on the Surface of Indonesian Bamboo Timber by TiO<sub>2</sub> Deposition and Using Octadecyltrichlorosilane as a Surface Modifier Agent

The tropical bamboo has been widely used in modern society as a potential material for various applications. It is well known that bamboo has low durability due to its hydrophilic properties. To overcome this problem, the superhydrophobic surface on Indonesian bamboo timber had been successfully fabricated via hydrothermal deposition of an anatase TiO2 and solution immersion of octadecyltrichlorosilane (ODTS), which exhibited a maximum water contact angle (WCA) of 155°. The as-fabricated superhydrophobic bamboo timber not only showed high mechanical resistance against the abrasion of SiC sandpaper but had also been proven to possess high chemical stability after immersion in acidic and basic aqueous solutions. Moreover, the superhydrophobic bamboo timber also demonstrated excellent self-cleaning and flame-resistance properties, in comparison to pure bamboo timber. It is believed that the strategy offered in this study can increase the utilization of bamboo timber for various purposes, especially as a self-cleaning material.

Effects of bamboo species, steam-heating treatment, and adhesives on mechanical properties and dimensional stability of oriented bamboo scrimber boards

Effects of bamboo species, adhesives, and steam-heating treatment (SHT) were examined relative to mechanical properties and dimensional stability of oriented bamboo scrimber board (OBSB) made from makino bamboo (Phyllostachys makinoi Hayata) and moso bamboo (P. pubescens (Mazel)) strips. Results indicated that OBSB produced using makino bamboo culms bonded with water-soluble phenol formaldehyde resin (PF) had significantly higher ultrasonic wave velocity (Vu (//)), tap tone sound velocity (Vt (//)), dynamic modulus of elasticity (DMOEu (//)), and DMOEt (//) than that produced using moso bamboo bonded with water-soluble urea formaldehyde resin (UF) (p < 0.05). The two types of OBSB showed the same trend of DMOEu > DMOEt > modulus of elasticity (MOE). In addition, OBSB made using steam-heated makino bamboo and PF had the largest modulus of rupture (MOR) (210.5 MPa), exceeding that of OBSB made using laminated bamboo timber and wood-plastic composite (WPC). However, OBSB made using steam-heated moso bamboo and UF exhibited the highest screw holding strength (SHS). Improvement in dimensional stability was observed in OBSB manufactured using steam-heated culms. Finally, OBSB glued with UF had lower water absorption, thickness swelling, and volumetric swelling than that glued with PF.

Evaluating the comprehensive influences of heat treatment and polydimethylsiloxane on integrated performance of bamboo timber.

The main objective of this work is to analyse the influence of heat treatment with polydimethylsiloxane on integrated performance of bamboo timber. Bamboo timber was heat treated using polydimethylsiloxane as a medium at 120, 150, 180 and 210 °C for 3 h in this study. Results revealed that the equilibrium moisture content (EMC) and linear swelling ratio of heat-treated bamboo specimens was remarkable decreased with increasing heat treatment temperature. The surface contact angle of water on the bamboo specimens was observed to increase with the increasing heat treatment temperature, indicating the reduction of wettability with water. Additionally, the modulus of rupture (MOR) and modulus of elasticity (MOE) was decreased with the increasing heat treatment temperature and lower than that of untreated specimens. Cellulose crystallinity of bamboo specimens was slightly decreased with the increase of heat treatment temperature. TG-DTG results illustrated a reduction in relative content of hemicellulose, and increase in relative content of lignin and cellulose of bamboo specimens with the increase of heat treatment temperature. Presence of the stretching vibration Si–C in Si–CH3 indicated the bonding of siloxane to bamboo timber by forming covalent bonds. The colour of the heat-treated bamboo timber was even deepened after heat treatment, endowing the bamboo timber with better surface decoration performance.

Evaluating the performance of bamboo forests managed for carbon sequestration and other co-benefits in Suichang and Anji, China

Using the Methodology for Bamboo Forest Management Projects for Carbon Sequestration and field data, we assess the performances of China Certified Emissions Reduction bamboo management projects for carbon sequestration in Suichang and Anji. We also explore the performance variation in response to differences in site condition and price and cost levels. Our results show that within a 30-year time period, the annual net present values (NPV) and carbon sequestration per hectare of the Suichang project are 3330.53 yuan (1 US dollar is about 6.7 Chinese yuan) and 7.19 tons, whereas they are 3895.53 yuan and 6.01 tons in Anji. Compared to the traditional bamboo forest management systems, large gains are found in bamboo timber and shoot revenues as well as the NPVs of carbon projects. Further, the NPV per unit area of the carbon sequestration project in Suichang, which has a poorer site condition, is lower than that in Anji, while Suichang's carbon sequestration revenue per unit area is higher than that of Anji. Variation in NPV can be caused by differences in site condition or price/cost factors.