Bamboo Culms Research Articles

Achieving sustainable built-environment using bamboo composite frame system with cow-dung masonry infills

In today's rapidly urbanizing world, there is dire need for adopting the principles of green/ sustainable built-environment so as to mitigate the ill effects of environmental degradation and climate change. However, demand for housing is on rise in developing countries like India, where sizeable population, especially the low-income strata, still lacks decent quality structurally safe housing. Extensive use of concrete and steel in construction over more than a century has led to detrimental environmental effects such uncontrolled release of greenhouse gases/ pollutants, deforestation and erosion, leading to now visible outcomes of climate change. Bamboo, on other hand provides a sustainable alternative to concrete and steel as a building material since it absorbs the atmospheric carbon dioxide, produces more oxygen than timber producing trees and is a lightweight and renewable building material. Unlike timber, it matures in four to five years and being grass family, is replenishable in nature. However, from structural point of view, the main drawback of bamboo culm is its large slenderness ratio, which renders it weak in resisting bending and compressive loads. This paper presents an alternate structural system utilizing fibre reinforced bamboo composite (FRBC) to overcome the structural deficiency of a single shoot bamboo and build a prototype structure after detailed laboratory evaluation and structural analysis. Structural elements made from FRBC are utilized for fabricating a prototype 3D frame structure, measuring about 24 m2 in plan, representing a modular unit amenable to horizontal and vertical expansion. Eco-friendly materials like cow-dung based bricks and mortar, which offer net zero additional carbon dioxide emissions and circumvent reliance on cement and river sand, have been utilized as masonry infills after structural evaluation. The built structure provides a proof-of-concept demonstration of the feasibility of using bamboo and cow-dung, sustainable building materials, for achieving a structurally safe built-environment. The technology is especially suitable for countries like India which are endowed with tropical climatic conditions. By adopting such environmentally friendly alternatives, the construction industry can create a healthier environment while addressing housing and infrastructure needs in sustainable manner.

Factors affecting the market outlet choice of bamboo culm producers in Banja district, Awi zone, Ethiopia

Factors affecting the market outlet choice of bamboo culm producers in Banja district, Awi zone, Ethiopia

Three-dimensional structural characterization and mechanical properties of bamboo parenchyma tissue

Bamboo is predominantly composed of parenchyma and fibers, with parenchyma constituting approximately 52% of the bamboo culm wall. The bamboo fibers function as the primary load-bearing elements, its structure and performance have been studied in detail. However, investigations concerning the structure and mechanical properties of parenchyma tissue remain limited. Consequently, this study focuses on the comprehensive characterization of the three-dimensional (3D) structure of bamboo parenchyma. Additionally, the study encompasses the evaluation of tensile and compressive properties of parenchyma tissue, along with an analysis and discourse on failure mechanisms. Parenchyma cells can be categorized into two types: long cells, accounting for approximately 89.37%, and short cells. The measured tensile strength and elastic modulus of the parenchyma tissue are 48.81 MPa and 706.48 MPa, respectively. The propagation of cracks leading to tensile failure predominantly occurs along the middle lamella, accompanied by partial penetration through cell walls. Concerning parenchyma tissue compression, three discernible stages can be identified: the elastic stage, plateau stage, and densification stage. The axial load-bearing capacity of parenchyma tissue exceeds that of the tangential and radial orientations. Axial compressive strength and elastic modulus of the parenchyma are measured at 18.82 MPa and 5.24 GPa, respectively. Compression failure modes in parenchyma tissue encompass compression bending and cell fracture, shear failure of the middle lamella, and detachment and debonding of the cell wall. The comprehensive structural and mechanical parameters derived from this investigation provide valuable insights for the development of numerical models and understanding the various mechanical properties of bamboo.

Dependency on bamboo by local communities in various agro climatic zones of Madhya Pradesh in India

A study has been carried out in 12 Forest Divisions of 11 agro climatic zones from Madhya Pradesh (India) in which 1374 Basod household were surveyed. The present work revealed that maximum income contribution of Basod families from traditional business were found in districts of Malwa Plateau agro climatic zone (65.12%) followed by, Satpura Plateau (58.8%), Vindhya Plateau (50.71%), Central Narmada Valley (47.25%), Chhattisgarh Plains (46.48%), Northern hills regions of Chhattisgarh (45.49%), Nimad Plains (41.53%), Jhabua hills (41.59%), Kaimur Plateau & Satpura hills (41.25%) whereas minimum contribution of Basod family annual income was found in Bundelkhand (38.79%) agro climatic zone. During the study it was observed that maximum number of consumption of bamboo for traditional business was found in districts of Bundelkhand zone (Average number of bamboo culms per annum is 421.6) whereas minimum number of consumption was observed in Satpura plateau (Average number of bamboo culms per annum is 171.6). Minimum average requirement of bamboo was found in Central Narmada Valley (657.6 culms per annum). This study revealed, cultivation of bamboo can be a profitable economy across the agro-climatic zones of Madhaya Pradesh, if proper coordination is maintained between farmers and traders.

SIFAT FISIS BAMBU SEPANJANG BATANG PADA BAMBU SERO (Schizostachyum brachycladum Kurz.)

SIFAT FISIS BAMBU SEPANJANG BATANG PADA BAMBU SERO (Schizostachyum brachycladum Kurz.)

Influence of flowering on the anatomical structure, chemical components and carbohydrate metabolism of Bambusa tuldoides culms at different ages.

Bamboo forests, which have come to occupy large areas in recent years, naturally undergo the process of blooming. However, bamboo culms and rhizomes degenerate after the plants bloom, resulting in widespread loss of raw materials. Systematic research on the properties and physiology of bamboo culms after flowering is lacking, and whether flowering bamboo culms could be used as raw materials in industry is unclear. In this paper, we compared and measured the fiber morphology, chemical components, and sugar metabolism indexes of non-flowering and flowering Bambusa tuldoides culms at different ages. The results showed that the fibers in the middle internodes of both non-flowering and flowering B. tuldoides culms had the longest length. The fibers completed their elongation within 1 year, but the fiber walls were continually deposited with age. The levels of the chemical components in the nonflowering culms also continually increased with age. The nonstructural carbohydrate (NSC) content and sugar metabolism indexes showed the highest levels in the 2-year culms and then declined in the 3-year culms. Compared to young culms that had not yet flowered, the 3-month-old and 1-year-old flowering culms had a significant decrease in the fiber length and tangential diameter, and their holocellulose and lignin levels also decreased, while the levels of ash, SiO2, 1% NaOH extractives, and benzene-ethanol extractives increased. A correlation analysis showed that sugar catabolism was accelerated in the flowering cluster, which could lead to "starvation death" in bamboo and which had a significant negative impact on the anatomical and chemical properties of the bamboo culms. Generally, the flowering bamboo culms had shorter fibers, higher levels of extractives and ash, and lower holocellulose content, which indicated that bamboo flowering has an adverse effect on the application of such components in the production of pulp, in papermaking, and in other processing and utilization activities. This study revealed the physiological changes in flowering B. tuldoides culms and provided a theoretical basis to inform the utilization of culms in this species.

Multi-locus phylogenetic analyses reveal eight novel species of Distoseptispora from southern China.

Plant debris are habitat favoring the growth of various microbial species. Over the course of our mycological surveys in Jiangxi and Yunnan Provinces, China, eight new Distoseptispora species, viz. D. gasaensis, D. guanshanensis, D. jinghongensis, D. longnanensis, D. menghaiensis, D. menglunensis, D. nanchangensis, and D. yichunensis collected on dead branches of unidentified plants, were introduced by morphological and molecular phylogenetic analyses. Multi-locus (LSU, ITS, TEF1, and RPB2) phylogenetic analyses were performed using maximum-likelihood and Bayesian inference to infer their taxonomic positions within Distoseptispora. Both molecular phylogenetic analyses and morphological characters supported them as eight independent taxa within Distoseptispora. This work improves our understanding of the diversity of Distoseptispora in southern China.IMPORTANCEDistoseptispora as a single genus in Distoseptisporaceae was introduced by morphological and phylogenetic analyses. Members of this genus occur mainly as asexual morphs, forming effuse, hairy colonies on decaying wood, plant stems, bamboo culms, and fallen leaves and shafts in terrestrial and freshwater habitats. In the present study, saprobic hyphomycetes from plant debris were investigated, and eight new Distoseptispora species were introduced based on morphology and phylogenetic analyses of LSU, ITS, TEF1, and RPB2 sequence data. This study provides important data on the species diversity, ecological environment, and geographical area of Distoseptispora, greatly updates the classification of Distoseptispora, and improves our understanding of the taxonomy of Distoseptispora.

Drying of Highland Bamboo (Oldeania alpina) Culms Grown in Ethiopia as Quality Enhancement

Drying is an essential step in the manufacturing process of bamboo culms which enhances its quality. Even though in the case of Ethiopia, effective bamboo culm drying has not been practiced. This is due to limited information/technology regarding bamboo culm drying. Therefore, this study aimed to investigate the effective drying technologies and the effect of site and culm height on the drying characteristics of Oldeania alpina (O. alpina). For this study, matured 3-5 years old samples of O. alpina culms sectioned into three segments were collected from Hagere-Selam and Rebu-Gebeya, Ethiopia. The culms were stacked and dried using kiln and air-drying methods. The mean values of basic density in O. alpina collected from Hagere-Selam and Rebu-Gebeya sites were 0.65 and 0.63 gcm-3, respectively. The average initial moisture content (MC) of Hagere-Selam and Rebu-Gebeya culms were 91.78% and 80.32%, respectively. The Hagere-Selam culm kiln-dried within 6.5 days while air-dried within 75 days to attain the final MC for kiln (10.15%) and air-drying (14.13%). The Rebu-Gebeya culm kiln dried within 5.4 days while they required 61 days for air-drying to attain the final MC for the kiln (10.60%) and air-drying (13.01%). The MC and drying time needed for drying the culms were significantly affected by site, culm height, and drying method. Drying O. alpina culms using kiln and air-drying methods was successful without significant drying defects. Well-seasoned culms of Hagere-Selam and Rebu-Gebeya are recommended for wider utilization in Ethiopia including furniture, flooring, handcrafts, etc.

The Impact of Bamboo Consumption on the Spread of Antibiotic Resistance Genes in Giant Pandas.

The spread of antibiotic resistance genes (ARGs) in the environment exacerbates the contamination of these genes; therefore, the role plants play in the transmission of resistance genes in the food chain requires further research. Giant pandas consume different bamboo parts at different times, which provides the possibility of investigating how a single food source can affect the variation in the spread of ARGs. In this study, metagenomic analysis and the Comprehensive Antibiotic Resistance Database (CARD) database were used to annotate ARGs and the differences in gut microbiota ARGs during the consumption of bamboo shoots, leaves, and culms by captive giant pandas. These ARGs were then compared to investigate the impact of bamboo part consumption on the spread of ARGs. The results showed that the number of ARGs in the gut microbiota of the subjects was highest during the consumption of bamboo leaves, while the variety of ARGs was highest during the consumption of shoots. Escherichia coli, which poses a higher risk of ARG dissemination, was significantly higher in the leaf group, while Klebsiella, Enterobacter, and Raoultella were significantly higher in the shoot group. The ARG risk brought by bamboo shoots and leaves may originate from soil and environmental pollution. It is recommended to handle the feces of giant pandas properly and regularly monitor the antimicrobial and virulence genes in their gut microbiota to mitigate the threat of antibiotic resistance.

Value Chain Analysis of Highland Bamboo (Yushania alpina) in Banja District, Awi Zone, Ethiopia

Bamboo is one of the most important vegetation resources in highlands of Ethiopia. In Ethiopia, understanding the socioeconomic significance of bamboo resources and linkages between policy makers and other organizations is a persistent issue for the expansion of bamboo industry. This study aims at analyzing the value chain of highland bamboo originating from Banja district, Awi zone, Ethiopia. Specifically, it investigates the current value chain structure of highland bamboo and the role of actors and identifies the existing upgrading strategies along the chain, estimates the market performance, analyzes the determinants that affect the market supply of highland bamboo, and analyzes the governance structure along the highland bamboo value chain. Primary data were collected from direct value chain actors such as 122 sampled households, 13 traders, 16 processors, and 30 final users through semistructured interview schedules, key informant interviews, focus group discussions, and personal observation. Descriptive statistics, multiple linear regression, and value chain analysis were employed to analyze the data. Government offices and international network of bamboo and rattan and micro and small enterprises were support service providers. The governance structures in the bamboo value chain differ from one stage to the other stage. The result of multiple linear regression model indicated that the land size allocated for bamboo plantation, number of culm harvested, access of market information, and silviculture management practice positively affected the market supply of bamboo culm, whereas distance to the market affected the market supply of bamboo culm negatively and significantly. Based on the findings of this study, designing policies help to increase farmers’ knowledge and skills through capacity building and help to improve information access, silviculture management practice, and market supply of culm.

Different hydraulic and photosynthetic responses to summer drought between newly sprouted and established Moso bamboo culms.

The subtropical regions in China are prone to recurrent summer droughts induced by the Western Pacific Subtropical High-Pressure, which has induced the death of tens of millions of culms of Moso bamboo (Phyllostachys edulis (Carriere) J. Houzeau), a widely distributed giant bamboo with high economic and ecological values. In the future, the intensity and frequency of the summer drought are projected to increase in these areas due to global climate change, which may lead to significant age-specific mortality of Moso bamboo. So far, it is still unclear about the age-specific response mechanisms of hydraulic traits and carbon balance of Moso bamboo when it is suffering to an ongoing summer drought. This study aimed to investigate the hydraulic and photosynthetic responses of newly sprouted (1 year old) and established (2-5 years old) culms of Moso bamboo to summer drought, which was manipulated by throughfall reduction in Lin'an of Zhejiang. The results showed that both newly sprouted and established culms had a gradually weakening hydraulic conductivity and photosynthesis during the whole drought process. In the early stage of the manipulated drought, the established culms had more loss of hydraulic conductivity than the newly sprouted culms. However, the newly sprouted culms had significant more loss of hydraulic conductivity and lower photosynthetic rates and stomatal conductance in the middle and late stages of the manipulated drought. The results suggest that the newly sprouted culms were more susceptible to summer drought than established culms due to the combined effects of hydraulic damage and photosynthetic restriction, explaining why the newly sprouted culms have higher mortality than elder culms when subjected to extreme drought. These findings provided insights into the mechanisms of Moso bamboo's age-specific drought-induced mortality, which will help for the anti-drought management of bamboo.

Cold pressing and hot curing process for assembly of hexagonal pre-shaped bamboo culm sections

Bamboo is widely used in the construction industry due to its excellent mechanical properties, short production cycle, and environmental concerns. Reconstructing and processing bamboo into biomass-based composite materials that can replace wood alleviates the imbalance between wood supply and demand. This article uses cold press setting and hot press curing molding processes to prepare small samples of Hexagonal Recombinant Bamboo Material (glued HexBam). Through orthogonal analysis, the preparation process parameters, adhesive types, adhesive application amounts, and the relationship between the temperature and time of hot pressing solidification molding and the mechanical properties of glued HexBam were determined. A phenolic adhesive (PF) was used with a dosage of 200 g/m2, a heat setting and molding temperature of 130 °C, and a heat setting molding time of 10 minutes. Under these process conditions, the prepared glued HexBam had a longitudinal compressive strength of 73.8 MPa and a specific strength of 0.0535 N•m/kg, which is superior to ordinary steel.

Anatomical and Transcriptome Analyses of Moso Bamboo Culm Neck Growth: Unveiling Key Insights.

The Moso bamboo culm neck, connected with the rhizome and the shoot bud, is an important hub for connecting and transporting the aboveground and belowground systems of bamboo for the shoot bud development and rapid growth. Our previous study revealed that the culm neck generally undergoes six different developmental stages (CNS1-CNS6), according to the primary thickening growth of the underground shoot bud. However, the molecular mechanism of the culm neck development remains unknown. The present study focused on the developmental process of the CNS3-CNS5 stages, representing the early, middle, and late elongation stages, respectively. These stages are densely packed with vascular tissues and consist of epidermis, hypodermis, cortex, and ground tissue. Unlike the hollow structure of the culms, the culm necks are solid structures. As the culm neck continues to grow, the lignin deposition increases noticeably, contributing to its progressive strengthening. For the transcriptome analysis, a total of 161,160 transcripts with an average length of 2373 were obtained from these stages using both PacBio and Illumina sequencing. A total of 92.2% of the reads mapped to the Moso bamboo reference genome. Further analysis identified a total of 5524 novel genes and revealed a dynamic transcriptome. Secondary-metabolism- and transport-related genes were upregulated particularly with the growth of the culm neck. Further analysis revealed the molecular processes of lignin accumulation in the culm neck, which include differentially expressed genes (DEGs) related to cell wall loosening and remodeling and secondary metabolism. Moreover, the upregulations of transcription factors such as MYBH and RSM in the MYB family play crucial roles during critical transitions in the culm neck development, such as changes in the angle between the rhizome and the culm neck. Our new findings provide essential insights into the cellular roadmaps, transcriptional networks, and key genes involved in the culm neck development.

A comprehensive evaluation of the effects of bamboo nodes on the mechanical properties of bamboo culms

Architectural pavilions made of round bamboo are undergoing rapid development due to their appealing appearance and low carbon footprint, but their structural analysis is challenging due to the existence of bamboo nodes. Generally, bamboo nodes provide positive effects on the mechanical behavior of bamboo culms in terms of evolution. However, the loading conditions of bamboo culms used in buildings greatly differ from the natural conditions. Some studies have been conducted on this issue but come to different conclusions. In this regard, this work conducts a comprehensive study on the effects of bamboo nodes on the mechanical properties of bamboo culms. A total of 168 specimens divided into four types were tested, including compressive, tensile and shear tests parallel to the grain and radial compressive tests. The load–displacement curves and failure modes were analyzed. The analysis of variance method was used to evaluate the effects of bamboo nodes on the mechanical properties. A comprehensive discussion based on fiber morphology is presented to explain the effects of nodes under different load conditions. Additionally, the fiber distribution in the diaphragm was observed, and the compressive strength of the diaphragm was tested. It was found that the bamboo node had significant effects on the tensile strength and radial compressive modulus. Compared to the bamboo culm without nodes, the tensile strength of bamboo culm with nodes decreased by 47%, while the node could improve the pipe stiffness by 123%. In compressive and shear tests parallel to the grain, the bamboo node showed slight effects on the strength. The differences in both strengths were all within 9% in value. Based on the geometric model, the relationship between the fiber morphology and the mechanical properties was built. In short, the bamboo node showed less improvement in compressive and shear tests parallel to the grain but should be carefully considered in tensile conditions due to its weakening effect.

Why bundengan musicians always drench their instruments prior to playing

Bundengan is an indigenous musical instrument from Indonesia. It evolved from a bamboo-woven dome originally used by duck herders as a portable shelter during rain and sun. By embedding strings and bars into the dome, the herders turned this shelter into a unique instrument, under which they sit and play music. Bundengan musicians have learned from experience that the instrument sounds better when played under the rain. Nowadays, they use various ways to drench their instruments prior to playing, such as soaking it in fish ponds or putting it under the shower. We explore the physics of why wetter bundengan sounds better. First, we analyze the construction steps of the bamboo dome: the weaving of the bamboo splits, the bending of the woven splits, the layering of bamboo culm sheaths on the woven splits, and the deformation of the sheaths during wetting. Second, we analyze the coupling between the mechanical vibrations in the dome and the acoustical waves from the instrument. Certain conditions of the coupling may lead to an evanescent acoustical field dominating over the radiating acoustical field, which may explain why the best bundengan sound is confined only to under the dome, where the musicians sit.

Physical and Chemical Properties of Highland Bamboo (Yushania alpina) Culms Grown in Ethiopia

Bamboo is the fastest growing plant currently known on earth, a property that enables it to be the best alternative as a future source of wood fi ber. This study investigated the effect of site and culm height on the physical and chemical properties of Yushania alpina culms grown in Ethiopia. Matured Yushania alpina 3 to 5-year-old samples were harvested from Hagere-Selam and Rebu-Gebeya sites. The culms were subdivided into three equal lengths (bottom, middle, and top), and the variations in physical and chemical properties between the two sites and the culm heights of Yushania alpina were investigated. The results showed that the average values of MC, basic density, tangential and longitudinal shrinkage of Yushania alpina culms for Hagere-Selam and Rebu-Gebeya sites were (91.78 and 80.32 %), (0.65 and 0.63 g/cm3), (6.63 and 5.84 %) and (0.63 and 0.56 %), respectively. The average values of cellulose, lignin, extractive and ash contents in the culms for Hagere-Selam and Rebu-Gebeya sites were (52.84 and 50.71 %), (26.55, and 26.04 %), (8.41 and 8.02 %) and (1.95 and 2.17 %), respectively. The results revealed that the site affected the MC, basic density, cellulose, lignin, extractive, and ash contents of Yushania alpina culms but not the tangential and longitudinal shrinkage. The culm height of Yushania alpina affected MC, basic density, tangential shrinkage, longitudinal shrinkage, cellulose, lignin, extractive, and ash contents. In the case of both sites, the highest percentages of MC, tangential and longitudinal shrinkage, and ash content were observed at the base and lowest at the top of the culms. On the contrary, both sites observed thehighest magnitude of basic density, cellulose and extractive at the top and lowest at the base of the culms. The variations in physical and chemical properties at different sites and culm heights infl uence the utilization of Yushania alpina culms for industries and end products.

A review of the evolution of research on proposals for bamboo culms connections in structural systems

Structural systems built from raw bamboo have been used for years due to its highly renewable characteristics, versatility, and abundance in various countries, e.g., China, Indonesia, all over South America, and especially Brazil. It is also considered a low specific weight material, which means it is easy to handle and transport. These characteristics make it a low-cost material for building construction. The objective of this systematic bibliometric review is to identify innovations in bamboo culms structural connections in order to contribute to the advancement of technology applied to civil construction by seeking joints that consider the use of industrialized or standardized products. This review revealed there is still no ideal connection capable of solving the great problem of this subject, which points out the need for more studies on the topic. This investigation also allows for the classification of the connections into 5 categories: Bolted connections; Steel member and Steel plate connections; Reinforced Connections with filler; Parameterized connections, and; Connections with the use of wooden dowels.

Quantitative morphological transformation of vascular bundles in the culm of moso bamboo (Phyllostachys pubescens).

Vascular bundles of bamboo are determinants for mechanical properties of bamboo material and for physiological properties of living bamboo. The morphology of vascular bundles reflecting mechanical and physiological functions differs not only within internode tissue but also among different internodes in the culm. Although the distribution of vascular bundle fibers has received much attention, quantitative evaluation of the morphological transformation of vascular bundles associated with spatial distribution patterns has been limited. In this study deep learning models were used to determine quantitative changes in the distribution and morphology of vascular bundles in the culms of moso bamboo (Phyllostachys pubescens). A precise model for extracting vascular bundles from cross-sectional images was constructed using the U-Net model. Analyses of extracted vascular bundles from different internodes showed significant changes in vascular bundle distribution and morphology among internodes. Vascular bundles in lower internodes showed outer relative position and larger area than those in upper internodes. Aspect ratio and eccentricity indicate that vascular bundles in internodes near the base have more elliptical morphology, with a long axis in the radial direction. The variational autoencoder model using extracted vascular bundles enabled simulation of the morphological transformation of vascular bundles along with radial direction. These deep learning models enabled highly accurate quantification of vascular bundle morphologies, and will contribute to a further understanding of bamboo development as well as evaluation of the mechanical and physiological properties of bamboo.

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.

Assessment of the drying behaviour of young and mature Bambusa vulgaris from Ghana

This study assessed the drying behaviour of young and mature Bambusa vulgaris culms and evaluated their utilisation potential. Two and four-year old Bambusa vulgaris culms were harvested and prepared to the required length of 21 internodes. The first seven internodes were taken as the bottom, the second seven were taken as middle and the last seven internodes were taken as the top. The study used samples from the bottom and top. Physical properties, including basic density and moisture content, were determined in accordance with ISO 13061–2 (ISO 2014) and EN 13183–1 (EN 2002), respectively, while shrinkage properties (radial, tangential, longitudinal and volumetric) were determined following established procedures. For the bottom and top portions of the mature bamboo after 18 days of drying, radial shrinkage values were 3.31% and 5.01%, tangential values were 4.95% and 5.78%, and longitudinal values were 0.28% and 0.35%, respectively. For the bottom and top portion of two-year-old culms, the values were 15.0% and 18.6% for radial shrinkage, 20.5% and 25.8% for tangential shrinkage and 0.46% and 0.47% for longitudinal shrinkage, respectively. The tangential shrinkage values were higher than the radial and longitudinal shrinkage values. The moisture content of the bottom part of the mature bamboo culm after 3 and 18 days of drying were 31.4% and 12.2%, while the young culms had values of 53.5% and 27.8%, respectively. Mature bamboo culms had better drying behaviour than young culms. Consequently, mature bamboo culms are more suitable for use in engineered composite materials.