EPS夹芯板受弯徐变的理论分析与试验研究

Theoretical Analysis and Experimental Research on the Creep Behavior of EPS Sandwich Panel Under Bending Load

EPS夹芯板作为新型的建筑保温隔热材料被广泛使用。但是由于对其在长期荷载作用下的徐变特性缺乏认识,使得在不同荷载、不同跨度下该如何选用板厚使其在工作一定年限后依然满足正常使用极限状态要求存在极大的困难,严重阻碍了夹芯板的应用及推广。采用6参数的Burgers模型对EPS芯材的剪切徐变柔量曲线进行了辨识,推导Burgers模型的本构方程,并借助数学分析软件拟合得到模型参数。然后导出以Prony级数的形式表达的剪切松弛模量的参数值,代入到有限元软件中对EPS钢面夹芯板在长期荷载作用下的徐变特性进行较为系统的分析,并通过试验来验证分析结果。

EPS sandwich panel has been widely used as new building insulation material,however its long-term creep behavior under load is unknown,it is hard for people to choose the panel to make sure the panel still meet the normal use limit state requirement after certain years of working.This greatly hinders the pace of the application and promotion of the sandwich panel.A six-parameter Burgers model was applied to describe the creep behavior of the EPS core material,and the constitutive equation of the Burgers model was deduced.The parameters of the model were got using mathematical analysis software to fit the experimental data.Then the relaxation parameter of the shear modulus,which was expressed in the form of prony series,were substituted into the finite element software to simulate the creep behavior of the whole panel under two-point bending long-term load.The result of the simulation fits the experiment very well.