In order to establish a nonlinear stress dependent constitutive model of asphalt treated base, incorporate it into mechanical pavement analysis and improve the accuracy of pavement structural analysis, the dynamic triaxial test was used to measure the resilient modulus of asphalt treated base in different stress state. The nonlinear stress dependent constitutive model was obtained. The finite element pavement analysis was carried out, and the material property was defined through user programed UMAT subroutine. The testing results show that, the resilient modulus of asphalt treated base has a strong stress dependent property. Within the stress state covered in the triaxial test, the maximum resilient modulus is 175% of the minimum value. From the finite element pavement analysis, compared to nonlinear analysis, the traditional linear elastic analysis underestimates the maximum tensile strain on the bottom of base about 10%, and underestimates the maximum compressive stress on the top of subbase about 5%. The pavement analysis results are significant affected by the stress dependent property and it needs to be included during pavement design process.%为建立沥青稳定碎石的非线性应力依赖本构模型,并将该模型应用于路面结构力学分析,提高路面结构分析的准确性.采用动三轴试验模拟不同应力状态,测试沥青稳定碎石的回弹模量,建立材料的非线性应力依赖本构模型;采用Abaqus有限元软件中的UMAT子程序编程并定义沥青稳定碎石的本构模型,进行基于沥青稳定碎石非线性应力依赖本构模型的路面结构数值模拟.结果表明:沥青稳定碎石的回弹模量有着较强的应力依赖特性,在研究所涵盖的应力状态下,其模量最大值为最小值的175%.通过有限元路面结构分析可知,与非线性分析相比,传统的弹性分析低估了沥青稳定碎石基层底部拉应变约10%,低估级配碎石顶部最大压应力约5%.沥青稳定碎石的非线性应力依赖特性显著影响路面分析结果,应在路面结构设计时考虑该特性.
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