重组竹横纹销槽承压强度的试验研究

Experiment Investigation on Dowel-bearing Strength Perpendicular to Grain of Parallel Strand Bamboo

设计4组竹销槽直径不同的试件来分析螺杆直径对重组竹横纹销槽承压强度的影响。根据试验结果评价美国木结构设计规范和欧洲木结构设计规范推荐的理论计算公式对重组竹的适应性。采用1 mm/min的速度加载至试件破坏。根据试验结果,得到了所有试件的荷载-位移曲线和极限强度值;并且得到基于美国规范5%d偏移法的屈服强度试验值。结果表明采用5%d偏移法得到的重组横纹竹销槽承压屈服强度值比较均匀,变异系数13.36%之内;并且其平均值随螺杆直径增大而减小,大于理论公式的计算结果;因此采用规范推荐的理论计算公式具有较高的可靠性。

Four group specimens in same dimension with only different dowel diameter were designed to analyze the affection of the diameter of bolts to dowel-bearing strength perpendicular to grain of parallel strand bamboo（PSB）,the application for PSB of the theoretical equations of American code and European code on dowel-bearing strength predication was assessed in terms of experiment.A loading velocity of 1 mm per minute was applied up to specimen failure,according to tested results,the load-displacement curve,ultimate bearing capacity and experimental yielded strength value based on 5% d offset approach in National Design Specification for Wood Construction of American National Standard Institute of all specimens were obtained.The results shows that the mean value of dowel-bearing strength perpendicular to grain based on the 5% d-offset parallel line is homogeneous,the coefficient of variation is less than 13.36%,and the average value decreases with the increasing in bolt diameter and is larger than that of code equations,moreover the theoretical equation on yielding strength is more reliable.