New Constitutive Relation for Granular Soils Based on RecentParticulate Mechanics Findings

这项探索性研究（SGER）小额赠款的资助是为了支持基于PI最近的一些颗粒力学发现的砂和其他颗粒介质的新本构关系的发展研究。这些发现揭示了在文章接触层面上的行为与期望的本构关系之间的一些简单而有力的联系。新的关系是基于PI开发的两个球体接触时的力-变形模型，并将通过计算机程序实现。初步评价表明，新关系式可以很自然地预测实验中观察到的应力诱导的各向异性、卸载时的体积收缩和循环加载过程中的致密化。用计算机程序进行参数化研究，并将预测结果与现有实验结果进行比较。最后，还将探讨将其他目前未包括在关系中的影响，如固结过程中的膨胀和非弹性行为，纳入基本颗粒力学考虑的方法。考虑到新的本构关系的基本颗粒力学基础以及它的强大和简单性，它应该对颗粒介质静载荷和循环载荷的分析建模产生重大影响。＊＊＊

CMS 97-28623 Dobry This Small Grant for Exploratory Research (SGER) award is funded to support research on the development of a new constitutive relation for sands and other granular media, based on some recent particulate mechanics findings by the PI. These findings reveal some simple and very powerful connections between behavior at the article contact level and the desired constitutive relation. The new relation is based on the force-deformation model at the contact between two spheres developed by the PI, and it will be implemented through a computer program. A preliminary assessment indicates that the new relation will naturally predict the stress-induced anisotropy, volumetric contraction upon unloading, and densification during cyclic loading observed experimentally. Parametric studies will be performed with the computer program, and the predications will be compared with available experimental results. Finally, ways will be explored to incorporate, also on the basis of fundamental particulate mechanics consideration, other effects currently not included in the relation, like dilation and anelastic behavior during consolidation. The new constitutive relation should have significant impact on the analytical modeling of static and cyclic loading of granular media, given its fundamental particulate mechanics grounding as well as its power and simplicity. ***