碎石料应力路径大型三轴试验的离散元模拟研究

发布时间：2018-06-27 23:01

本文选题：高填方 + 离散元　；参考：《工程力学》2014年10期

【摘要】：碎石料在高填方工程中得到广泛应用。由于其粒径较大,对碎石料力学特性的研究通常需要大型的试验设备。该文探索通过离散元数值模拟方法研究碎石料的应力路径相关力学特性。离散元程序可以将若干球形单元粘结成一个捆绑单元,从而模拟可破碎的碎石颗粒。该文首先简要介绍了离散元的计算原理、特点和模拟过程,并建立碎石料试件的离散元模型。通过对比一组恒定围压下的大型三轴试验,确定了各参数,对所建模型进行了标定。进而通过该模型独立预测碎石料试件在三种不同应力路径加载时的应力-应变关系及体变特性,并与相应的应力路径大型三轴试验结果进行对比,验证了离散元方法可以较为准确地计算碎石料沿不同应力路径加载时的力学特性,同时还讨论了碎石料的小应变刚度特性。
[Abstract]:Gravel is widely used in high fill engineering. Because of its large particle size, the study of mechanical properties of crushed stone usually requires large test equipment. In this paper, discrete element numerical simulation method is used to study the stress path related mechanical properties of crushed stone. The discrete element program can bond several spherical elements into a binding element, thus simulating broken gravel particles. In this paper, the calculation principle, characteristics and simulation process of the discrete element are briefly introduced, and the discrete element model of the gravel specimen is established. By comparing a group of large triaxial tests under constant confining pressure, the parameters are determined and the model is calibrated. Furthermore, the stress-strain relationship and bulk deformation characteristics of crushed stone specimens under three different stress paths are independently predicted by this model, and the results are compared with the corresponding large triaxial test results of stress paths. It is verified that the discrete element method can accurately calculate the mechanical properties of gravel under different stress paths, and the small strain stiffness characteristics are also discussed.
【作者单位】：清华大学土木工程系;
【基金】：国家973计划项目(2014CB047003) 国家自然科学基金项目(41272280) 高等学校博士学科点专项科研基金课题项目(200800031061) 国家高技术研究发展计划(863计划)项目(2007AA11Z113)
【分类号】：TU41

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