全风化花岗岩路基路面结构动力特性模型试验研究

路基路面结构受交通动荷载重复作用,表现出疲劳特性,并会产生不可恢复的残余塑性变形。通过3组室内大比例模型试验,研究了全风化花岗岩、全风化花岗岩水泥稳定土和土工格室加强等不同路基结构形式的路基路面结构受交通动荷载作用的动力特性,分析了路基路面结构动应力应变分布规律,得到路基路面结构动应力、应变和永久变形随车辆荷载大小、车辆荷载通过量(对应加载次数)、运行速度的变化规律,试验论证了全风化花岗岩及其水泥稳定土和土工格室加强作为高速公路路基填料的可行性和适用范围,评价了路基处理的效果,确定了路基质量控制标准,对高速公路的设计与施工具有指导意义。

Research of the Dynamic Performance of the Full Weathering Granite Subgrade and Pavement by Model Test

Subgrade has fatigue characteristic with residual plastic deformation under cycle dynamic traffic loads.The residual plastic deformation is determined by dynamic strength of roadbed filling and the actual level of dynamic stress.Through full scale model experiment,the variations of the subgrade dynamic strain and stress and total deformation are discussed under the conditions of three subgrade soil including full weathering granite,cement stable soil and reinforced soil with geogrid.The variations of the dynamic strain and stress with velocity and subgrade strength are analyzed.The design norm of the dynamic strength and modulus on which the full weathering granite and cement stable soil are used in expressway are presented.The reliability of this granite as filling soil is expounded and proved by experimental study.It is successfully applied to Lingxiang-Changsha Expressway's subgrade construction with full weathering granite.