水泥沥青砂浆损伤本构关系研究

摘要

水泥沥青砂浆（CA 砂浆）是高速铁路板式无砟轨道的充填层材料。采用 CSS8810电子万能试验机对不同龄期的 CA 砂浆进行了单轴压缩试验，结果表明：CA 砂浆的力学性能具有明显的龄期效应，峰值应力和弹性模量随龄期的增长而逐渐增大；CA 砂浆的应力－应变关系具有明显的应变硬化特性，沥青网络结构的横向约束作用是其主要影响因素。考虑损伤部分通过相互摩擦仍具有一定的承载能力，通过理论推导建立了 CA 砂浆的损伤本构关系，拟合结果与试验曲线一致性较高，能够有效体现 CA 砂浆力学性能的龄期效应和应变硬化特性。研究成果有望进一步推动 CA 砂浆力学性能的研究进展。%Cement and asphalt mortar (CA mortar)is the filling layer material of the slab track of high-speed rail-way.Uniaxial compression test was carried out on CA mortar specimens of different ages by CSS881 0 electronic u-niversal testing machine.Results show that the mechanical properties of CA mortar display obvious age effect,and the peak stress and elastic modulus gradually increase with the growth of age.The stress-strain relation of CA mor-tar displays obvious strain hardening characteristic,and the lateral constraint of asphalt network structure is the main influencing factor.Through theoretical derivation,the damage constitutive relation of CA mortar was estab-lished in consideration of the carrying capacity of the damaged part through mutual friction.The fitting result is highly consistent with test curves,and effectively reflects the age effect and strain hardening characteristics of the mechanical properties of CA mortar.The research result is expected to promote the research on mechanical proper-ties of CA mortar.