沥青路面加热型密封胶的低温黏弹性模型

Low-temperature Viscoelastic Model for Hot-Poured Sealant of Asphalt Pavement

为了描述加热型裂缝密封胶在低温条件下的应力-应变本构关系,以标准线性固体模型为基础,利用玻尔兹曼叠加原理对密封胶在拉伸-松弛过程中的力学行为进行分析,建立密封胶拉伸-松弛阶段的理论方程.采用ASTM D5329的粘结试验方法,选择6种加热型密封胶进行常应变拉伸-应力松弛试验,3种应变量分别为2.25 mm、3.75 mm和6.90 mm,采用标准线性固体模型拟合试验数据,求得拉伸和应力松弛回归方程.实验结果表明,标准线性固体模型可以较理想地拟合密封胶在低温条件下的黏弹性力学行为,应变量越小,模型的拟合精度越高.

In order to describe the constitutive stress-strain relationship of hot-poured bituminous crack sealants at low service temperatures,the mechanical behavior of extension-relaxation process was analyzed by Boltzmann superposition principle based on standard linear model.The extension-relaxation equations of sealants were deduced.The constant strain extension and stress relaxation tests of six sealants were conducted with the bond test of ASTM D5329.Three strains were 2.25 mm,3.75 mm and 6.90 mm respectively.Standard linear solid model was used to characterize the test results,and the fitting equations of extension and relaxation were developed.The equations displayed agreement with the test results very well both in the extension and relaxation process.It turned out that the mechanical behavior of hot-poured sealants can be accurately described by standard linear solid model,and the fitting accuracy of the model is higher when the strain is smaller.