沥青混合料局部三轴压缩试验方法

Method of partial triaxial compression test for asphalt mixture

为了优化常规三轴压缩试验与单轴贯入试验,介绍了局部三轴压缩试验原理、试验设计方法及过程等.基于与沥青路面实际受力情况相似的原则,通过ANASYS有限元论证了该方法的可行性.认为公称最大粒径及试件提供的围压是影响压头直径的主要影响因素,实际路面层厚与试件径高比是确定试件高度的主要因素,并设计了压头和试件的直径与高度.对AC13,SMA13和PA13三种级配沥青混合料进行局部三轴压缩试验,结果发现,该试验与常规三轴压缩试验的结果规律性一致.该试验具有应力状态明确,符合实际路面围压情况,所得参数的规律性、稳定性和准确性较好,且试验方法简单的优点.

In order to optimize the conventional triaxial compression test and uniaxial penetration test, the principle, design method, and testing process of partial triaxial compression test （ PTCT） are introduced.This method is verified by using ANSYS finite element method based on the similar stress of asphalt pavement.The nominal maximum aggregate size and confining pressure provided by specimen are considered as key factors to determine the diameter of platens.The specimen＆#39;s height is determined by the layer thickness of actual asphalt pavement and the diameter height ratio of speci-men.And the size of platens and the height and diameter of specimen are designed.Three types of asphalt mixtures, AC13, SMA13 and PA13, were tested by PTCT.The results show that the re-sponse of asphalt mixtures in PTCT fits in with that in the conventional triaxial compression test.The PTCT represents clear stress state characteristics of asphalt mixtures and accords with the actual con-fining pressure of asphalt pavement.The regularity, stability and accuracy of PTCT parameters are better than those of conventional triaxial test.Also, PTCT is easy to be carried out.