黏质路基土永久变形改进计算方法

通过室内重复荷载三轴试验,测试了36种工况下黏质路基土永久应变与试验加载次数之间的关系；采用统计回归的方法对黏质路基土永久变形预估模型进行了标定与修正.以分层应变总和法为基础,结合道路渠化交通的考虑,提出了分条分层总和法作为柔性路面路基土在车辆重复荷载作用下永久变形的改进计算方法,并详细说明该方法的计算原理及步骤.结合典型柔性路面结构实例,计算了黏质路基土的永久变形量,并通过对比分析,验证了该方法的合理性.

Improved Calculation Method of Permanent Deformation for Cohesive Subgrade Soil

The paper presents a study on permanent deformation characteristics of clayed subgrade soils on the basis of the repeated load triaxial test. The relationship between permanent strain and loading times was tested through 36 working conditions. A prediction model for permanent deformation of cohesive subgrade soils is established by improving and calibrating AASHTO 2002 model. With a consideration of the highly channelized road traffic, the itemize and layerwise summation method is proposed on the basis of the layerwise summation method as the improved method to calculate permanent deformation of cohesive subgrade soil under vehicle repeated load, calculation principle and steps of the proposed method were explained in detail. Based on a case study of a typical asphalt pavement structure, permanent deformation of clayed subgrade soils is calculated, and a comparative study verifies the rationality of this method.