静态和动态法测定加拿大SPF结构材弹性模量

Evaluation of modulus of elasticity of Canadian SPF structural lumber using static and dynamic methods

运用静态3点弯曲试验和动态两端自由梁振动试验对加拿大SPF(云杉-松树-冷杉)结构材的弹性模量进行测试,分析了两种方法测量弹性模量的特点、联系及差异。试验结果显示,该批试件的平均弹性模量高于美国林务局林产品实验室《木材手册》提供的数据,静态法测试的弹性模量与动态法测试的没有显著差异。此外,节子、裂纹等缺陷是影响SPF结构材弹性模量的重要因素。

The modulus of elasticity（ MOE） of Canadian SPF（ spruce-pine-fir） structural lumber was measured respectively using static（ three-point bending） and dynamic（ free-free beam vibration） methods. Characteristics,relationships and differences of MOE determined by these two methods were analyzed and discussed. The results showed that the average MOE of the tested specimens were higher than the data recorded in Wood Handbook published by Forest Products Laboratory of the USA. The difference between MOE tested by static and dynamic methods were not significant. Meanwhile,defects such as knots,cracks,etc. were important factors affecting the MOE of Canadian SPF structural lumber.