轻型木桁架齿板连接件的动态弹性模量测试研究

Test Research on Dynamic Elastic Performance of Tooth Plate Connector of Light Wood Truss

为了推广轻型木结构在我国的发展,应该对齿板连接方式进行详细的研究,为齿板连接的木桁架提供一些设计、验算的试验依据。依据结构动力理论,采用瞬态激励法,对用于木桁架下弦杆的单杆和齿板连接组合杆进行固有频率的无损测量和动态弹性模量的计算。探究了横向放置和纵向放置两种不同放置方式对动态方法测试杆件弹性模量的影响以及杆件在齿板连接前后的刚度变化。结果表明:杆件横置和纵置时测得的动弹性模量值基本一致,不同放置方式对测得的动弹性模量值影响不大;在加上齿板后,杆件的动弹性模量值减小了5.5%,结构整体的刚度有所降低。运用无损检测试验方法,直接使用工厂生产的工程材料,以期为轻型木桁架及齿板连接件的结构优化设计工作提供技术支撑,具有工程应用价值。

In order to promote the development of light wood structures in our country,detailed research should be carried out on the connection methods of the toothed plates,so as to provide some experimental basis for the design and calculation of the wooden trusses connected by the toothed plates.Based on the structural dynamic theory,this paper adopts the transient excitation method to perform the non-destructive measurement of the natural frequency and the calculation of the dynamic elastic modulus of the single rod and the toothed plate connecting composite rod used for the lower chord of the wooden truss.The effects of two different placement methods,horizontal placement and vertical placement,on the elastic modulus of the rods tested by the dynamic method and the stiffness changes of the rods before and after the tooth plate connection are explored.The results show that the dynamic elastic modulus values measured when the rods are placed horizontally and vertically are basically the same,and different placement methods have little effect on the dynamic elastic modulus values measured in this study.After adding the tooth plate,the dynamic elastic modulus value of the rod is reduced by 5.5%,and the rigidity of the whole structure is reduced.This article uses non-destructive testing methods and directly uses the engineering materials produced in the factory to provide technical support for the structural optimization design of light-weight wooden trusses and tooth plate connectors,which has engineering application value.