地面沉降的三维离散元模型建立和模拟研究

项目名称： 地面沉降的三维离散元模型建立和模拟研究

项目编号： No.41302216

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 天文学、地球科学

项目作者： 刘春

作者单位： 南京大学

项目金额： 26万元

中文摘要： 本项目从土体结构系统为松散堆积物这一特点出发，建立具有一定力学性质砂颗粒、粘土颗粒的离散元模型，并构建用于模拟地面沉降过程的三维离散元模型；自主研发软件"MatDEM"以进行特定的三维离散元模拟；根据土体的成分和级配，建立相应离散元模型并模拟土体压缩沉降过程，与实验中土体的压缩沉降特性及其微观结构变化进行对比分析；开展土体地下水抽取和回灌过程的模型箱试验和三维离散元模拟，揭示土体结构系统在地下水抽取和回灌过程中的不可逆变化及宏观变形响应，为地面沉降的研究提供一种新的研究方法。

中文关键词： 地面沉降；离散元法；数值模拟；抽灌水；负孔隙水压力

英文摘要： On the basis of the characteristic that soils are loose debris in micro scale, discrete element models for sand particles and clay particles will be built in the project, with which a three-dimensional discrete element model can be established for the simulation of land subsidence. A software "MatDEM" will be developed to run specific three-dimensional discrete element simulation. According to the analysis of composition and gradation of soils, corresponding discrete element models will be built to simulate the processes of soil compression and subsidence, which can be compared with the characteristics of soil compression and variation of micro structures during soil experiments. Both three-dimensional numerical simulations and experiments of soil ground water extraction and reinjection processes will be established, to reveal the irreversible changes of soil structures and the macro response during water extraction and reinjection processes. The project provides a new research method for the study of land subsidence.

英文关键词： land subsidence；discrete element method；numerical simulation；pumping-recharging；negative pore water pressure