As focus is drawn toward more sustainable construction practices, use of bamboo as a structural building material is growing as a topic of interest. It is highly renewable, has low-embodied energy, and has the highest strength-to-weight ratio of steel, concrete, and timber. Composite lumber made from bamboo, termed laminated bamboo lumber (LBL), has gained the particular interest of researchers and practitioners of late, since it has bamboo's mechanical properties but can be manufactured in well-defined dimensions, similar to commercially available wood products. Its primary drawbacks are that it is difficult to connect and is more costly than competing, locally available materials. This paper presents the advantages and challenges of embracing LBL as an alternative building material. Experimental and analytical data on production, performance, economics, and environmental impact of bamboo and LBL are reviewed, synthesized, and further analyzed to present an overview of the viability of using bamboo as a structural material in North America.

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This paper introduces a new, structural wood-concrete composite system. The system is formed by joining a wood component, such as a floor beam or laminated plate, to a concrete slab utilizing a continuous steel mesh of which one half is glued into a slot in the wood while the other half is embedded into the concrete. Two series of tests were performed and are presented: static push-out tests ͑to establish shear properties of the connector͒ and a full scale bending test with a span of approximately 10 m. Test results reveal that the steel mesh performs favorably-as a stiff yet ductile shear connector between the wood and the concrete. Design equations, per European standards ͑in absence of North American standards͒ are described and used to predict the failure load of the bending test. Calculations indicate that the tested beam performs with near full composite action-specifically, 97% effective stiffness and 99% strength of that of a beam with full composite action. This is a marked improvement in the efficiency of wood-concrete systems developed to date. The system shows itself to be superior to alternative systems in its high structural efficiency as well as being relatively easy to install and economic.

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A nonlinear stochastic model has been formulated to simulate the stress-strain behavior of strandbased wood composites based on the constitutive properties of the wood strands. Prediction models of this type save time and money in the development of wood composites by computationally gauging the effects of varying raw material characteristics with limited fabrication and testing of the full-scale product. The proposed model uses a stochastic-based materially nonlinear finite-element code with extended capacity to perform Monte Carlo simulations to predict the stress-strain behavior of [Ϯ15] s and [Ϯ30] s angle-ply laminates in tension and compression. The nonlinear constitutive behavior of the wood strands is characterized within the framework of rateindependent theory of orthotropic plasticity, where the plastic flow rule is in accordance with the Tsai-Wu criterion. Shear strength and stiffness of the strands, as well as the interaction parameter of the Tsai-Wu criterion have been estimated through a minimization technique developed in the present study. The model's accuracy was validated through comparisons of the numerical simulation results and experimental data. Excellent agreement was found.

Interest in the engineering performance of bamboo is on the rise primarily due to its rapid regenerative qualities and high strength-to-weight ratio. It has been a standard, sustainable building material for thousands of years in Asia and South America, where it grows naturally. Although there are many examples of magnificent bamboo structures, standards and documentation on safe and reliable bamboo design are scarce, particularly for connection design. Traditional connections involve friction-tight lashings (eg. ropes and cords of dried grasses) and pin-and-socket connections such as dowels and pegs, but more recent advances have involved integration with steel hardware and concrete. This paper presents bamboo as a feasible alternative building material and presents a review of past, current and emerging technologies to join hollow bamboo culms in structural applications. The paper's intent is to give an overview of the current state of bamboo connection technology and to promote developments in the emerging field of bamboo engineering. Recent technological advances and visionary architects have proven that it is possible to create safe structures that are not only sustainable but have tremendous potential for use in disaster relief and quick-build scenarios.

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