用振动方式测定足尺人造板弹性模量

为了无损检测足尺人造板的弹性模量，提出一种基于薄板横向自由振动原理的测定方法。利用自行开发的足尺人造板力学性能检测试验装置，以206张足尺人造板为试验对象，包括86张刨花板和120张胶合板，进行了测定试验。同时，从每张板材上裁制6块小试件，通过传统的小试件3点弯曲检测法来获得静态弹性模量，并将2种检测方法的结果进行对比。结果表明:以所有足尺人造板为研究对象，足尺人造板动态弹性模量比其静态弹性模量稍大，两者比值为1.03~1.22；2种检测方法获得的足尺人造板弹性模量值间的相关系数为0.94（P<0.001），证明基于薄板横向自由振动原理的足尺人造板弹性模量振动方式测定是可行的。图5表4参19

Measuring modulus of elasticity of full-size wood composite panels using vibration method

In order to detect the modulus of elasticity of full-size wood composite panels non-destructively, this research presents a test method based on the transverse free vibration of thin plate. A laboratory testing apparatus for measuring mechanical performance of full-size panels was built. Two hundred and six pieces of full-size wood composite panels including eighty-six pieces of particleboard panels and one hundred and twenty pieces of plywood panels were tested. Following free vibration testing, six small specimens were cut from each panel and traditional static mid-point bending test was then performed on each specimen to obtain static MOE. Then, the test results of two methods were compared. The results indicated that:all the full-size wood composite panels as the research object, the dynamic MOE of full-size panels by vibration method was slightly higher than their static MOE and their ratio were in the range of 1.03-1.22; a highly significant correlation relationship (P<0.001) was found between dynamic MOE and static MOE of full-size panels,which proved that determination of modulus of elasticity of full-size wood composite panels based on the transverse free vibration of thin plate was feasible.[Ch, 5 fig. 4 tab. 19 ref.]