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A strand-particle board SPB was manufactured using unoriented strands for the surface layers and unoriented particles for the core layer. Todomatsu Abies sachalinensis strands, recycled waste wood particles, and emulsifiable methylene diphenyl diisocyanate EMDI as a resin adhesive were used. The effect of resin content 3 and 6% , surface moisture content 5, 10, 15 and 20% and press temperature 170, 200 and 230 C on physical properties, and the effect of resin content 10% , surface moisture content 20% and press temperature 170, 200 and 230 C on blisters were investigated using laboratory boards. The results are summarized as follows :1 A suitable manufacturing condition for the EMDI bonded SPB was found to be a press temperature of 230 C, a resin content of 6%, and a surface moisture content of 15%. This condition produced the most superior properties, namely a board density of 0.62 g/cm 3 , an internal bond of 0.93 MPa, a modulus of rupture of 43.1 MPa and a thickness swelling of 1.9%.2 There were blisters in surface strand layers of all manufactured boards when surface moisture content was 20%.3 It was supposed that the carbon dioxide generated by the reaction of EMDI and water influences blisters and physical properties.

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Strength tests of madake (Phyllostachys reticulate) and mosochiku (Phyllostachys pubescens) culms, which are useful bamboos in Japan, were conducted in the green condition. Internal diameter d was estimated from external diameter D in the culm by the known regression line d＝0.81D. Section properties in the culm were calculated from D and d. Strength properties of the culm were calculated from the assumptions that the culm was homogeneous and a hollow circular cross-section material. As a result of tests, the strength properties of the culm could be expressed by several regression lines with external diameter D as explanatory variable. Of these, regression lines of stiffness data (flexural rigidity E・I, axial rigidity E・A, torsional rigidity G・J) necessary for structural analysis of space frame are as follows, regardless of bamboo species.Log E・I＝3.