基于细观特征分析的冰水堆积体渐进破坏机理多尺度研究

项目名称： 基于细观特征分析的冰水堆积体渐进破坏机理多尺度研究

项目编号： No.51309089

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 水利工程

项目作者： 石崇

作者单位： 河海大学

项目金额： 25万元

中文摘要： 冰水堆积体是冰川搬运堆积形成的一类土石混合介质，具有很强的非均匀、非连续和非线性特征。针对冰水堆积体宏细观力学行为发展相应的多尺度分析模型，有助于揭示细观行为影响边坡渐进破坏过程的机理。首先对冰水堆积体材料中的岩块通过三维激光扫描手段进行空间定位与几何外轮廓的构建，得到细观特征的表征量，如界面面积、粗糙度等，分析其细观特征对介质力学行为的影响；借助室内大三轴试验与滑槽堆积试验揭示介质细观特征与岩土力学参数的内在联系；采用粘结组合等方法构造土体和块石颗粒单元，发展非球形颗粒离散元的非线性接触模型，建立冰水堆积体的连续-离散耦合数值算法，揭示冰水堆积体由局部破坏向整体破坏的演化机理。本项目借助细观特征统计与力学行为试验，建立数值分析多尺度方法，揭示冰水堆积体渐进破坏机理，可为冰水堆积体的稳定性分析提供科学依据。

中文关键词： 冰水堆积体；细观特征；多尺度分析；渐进破坏；离散元

英文摘要： Talus deposit is a kind of soil-rock mixture medium formed by glacial movement and transportation，which has the strong heterogeneity, discontinuous and nonlinear characteristics. Developing corresponding mechanical analysis model according to the macro and micro mechanical behavior of outwash congeries can describe the mechanism of progressive failure process and help to reveal the microscopic behavior. Firstly the 3D laser scanning method is used to construct spatial orientation and geometric contour of rock mass in outwash congeries material ,the characterization of microscopic features such as the interface area, roughness can be obtained, and the influence of micro-structural factors on mechanics behavior can be studied. Secondly the indoor three triaxial test and the chute stacking tests are used to real the inherent contact between medium microstructure and mechanical parameters of rock and soil particles, then bond portfolio construction method of soil and rock particles to describe meso-characteristics in order to develop a non spherical particles of discrete nonlinear contact model, then continuous and discrete coupled numerical algorithm of outwash congeries is established to reveal the outwash evolution mechanism of failure by local damage to the whole.This project beginning with microstructure and

英文关键词： talus deposit；meso-structure characteristic；multi-scale analysis；progressive failure；DEM