PVC-U型材弹性模量测试偏差分析

在对PVC-U型材弹性模量试验中发现，同一样品的规则样条与不规则样条的弯曲弹性模量相差较大。不规则样条的负荷-挠度曲线上会出现拐点，如果不对曲线进行处理直接计算得到的弯曲弹性模量偏小。在不规则样条的负荷-挠度取拐点后直线段切线与横坐标的交点作零点修正后所测得的弯曲弹性模量比较接近真实值。通过实验可以验证处理后的方法测得的弹性模量与均匀规则样条的弯曲弹性模量相近。

Testing Deviation Analysis of Flexile Modulus of PVC-U Profiles

In the testing of the flexile modulus of PVC-U profiles, the load-deflection trace varied with the shapes of the samples, an inflection appeared when using irregular samples. The flexile modulus for irregular samples was generally lower than the usual values. In order to remove the deviation, an improved method was proposed. Drawing a tangent after inflection and intersected the abscissa, the slope of the tangent was taken as the flexile modulus. Thus the obtained value was closer to the regular ones.