混合多位移模式的非连续变形分析法研究

发布时间：2018-04-04 23:20

本文选题：DDA　切入点：线性位移模式　出处：《岩土力学》2016年03期

【摘要】：传统的非连续变形分析法(DDA)法采用简单的线性位移模式计算效率高,描述大块体的高阶多项式位移模式在一定程度保留了该特点,并提高了计算精度。近年来流行的耦合有限元、自然单元的DDA法实质上是引入相应的插值形函数构成块体位移函数,计算相对低效,但具有计算更精细、更容易施加边界条件等优点。为结合传统DDA法与DDA耦合法各自的优点,建立了一种同时利用传统DDA法线性位移模式与耦合型DDA法非线性位移模式的混合法。该方法非线性模式主要针对大块体,采用了自然单元插值,缘于其具有一定无网格特征,且效率比有限元高。建立了混合模式下的整体矩阵并推导出接触等因素刚度子矩阵和荷载子向量的具体表达式。该方法建模更加方便合理,计算精度、效率介于线性模式的传统DDA法和非线性位移模式的耦合法之间。通过基本算例验证了混合法的有效性,并给出了节理围岩-隧道衬砌整体分析模型的计算结果,体现了新方法的优越性。
[Abstract]:The traditional method of discontinuous deformation analysis (DDAA) has high computational efficiency using simple linear displacement model. The higher-order polynomial displacement model for describing large blocks retains this characteristic to some extent and improves the accuracy of calculation.In recent years, coupled finite element method (DDA method) has been widely used. In essence, the DDA method of natural element is to introduce the corresponding interpolation form function to form the block displacement function, and to calculate the displacement function relatively inefficiently, but it has the advantages of more precise calculation and easier application of boundary conditions.In order to combine the advantages of the traditional DDA method and the DDA coupling method, a hybrid method using the linear displacement model of the traditional DDA method and the nonlinear displacement model of the coupled DDA method is established.The nonlinear model is mainly used for large blocks and natural element interpolation is used because it has some meshless features and its efficiency is higher than that of finite element method.The global matrix in mixed mode is established and the concrete expressions of stiffness submatrix and load subvector of contact and other factors are derived.This method is more convenient and reasonable in modeling, accuracy and efficiency is between the traditional DDA method of linear model and the coupling method of nonlinear displacement mode.The effectiveness of the hybrid method is verified by a basic example, and the calculation results of the whole analysis model of jointed surrounding rock and tunnel lining are given, which reflects the superiority of the new method.
【作者单位】：宁波工程学院建筑与交通工程学院;中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验;
【基金】：973项目(No.2014CB047100) 浙江省自然科学基金(No.LY13E080009,No.Y1111133)~~
【分类号】：TU45

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