一种新型复合木梁的受弯性能研究

Study on flexural behaviour of a novel wood composite beam

主要研究了杨木旋切板胶合木(LVL)受弯构件的结构性能,建立了受弯构件的计算模型。通过试验,探讨了材料的部分物理力学性能,分析了受弯构件的破坏形态与破坏机理,并将其受弯性能与建筑中常用的锯材构件作了对比分析。试验结果表明,LVL梁的结构性能大大超出了锯材构件,其不仅具有较高的强度与刚度,还具有较低的强度变异性;分析了旋切板厚度与荷载作用方向对构件结构性能的影响;验证了平截面假定。利用极限应变法对构件的弯曲性能进行了理论分析,其结果与试验结果吻合良好。

The structural behavior of poplar laminated veneer lumber （LVL） beams is reported, and a design model is put forward. Based on the experimental work, some physical and mechanical behaviors of the materials are discussed. And then the failure modes and failure mechanism of the tested beams are analyzed. Also the flexural behaviors are studied and then compared with structural sawn timber beams. The experimental results show that the structural behaviors of LVL beams are much better than those of sawn timber beams. Its strength variability is lower as well as it has higher strength and stiffness for LVL beams. In addition, the influences of the veneer thickness and the load direction on the structural performance are discussed. Also the test results show that the plane cress-section assumption is valid. Moreover, the limiting strain method is used in the theoretical study of the flexural behavior of the beams, and the theoretical analysis shows a good agreement with the experimental results.