基于无网格界面模拟方法的面板坝防渗体跨尺度分析  

The cross-scale analysis of concrete-face rock-fill dam anti-seepage structure based on the simulation of meshfree interface

作　　者：邹德高[1,2] 龚瑾 孔宪京[1,2] 刘京茂[1,2] 屈永倩 ZOU Degao;GONG Jin;KONG Xianjing;LIU Jingmao;QU Yongqian(State Key Laboratory of Coastal&Off shore Engineering,Dalian University of Technology,Dalian 116024,China;School of Hydraulic Engineering,Dalian Univercity of Technology,Dalian 116024,China)

机构地区：[1]大连理工大学海岸和近海工程国家重点试验室,辽宁大连116024 [2]大连理工大学水利工程学院,辽宁大连116024

出　　处：《水利学报》2019年第12期1446-1453,1466,共9页Journal of Hydraulic Engineering

基　　金：国家重点研发计划项目(2017YFC0404904);国家自然科学基金项目(51779034);中央高校基本科研业务费(DUT19ZD216)

摘　　要：混凝土面板作为面板坝关键的防渗结构,其安全性态至关重要。由于防渗面板与堆石体尺寸相差悬殊,如何在保证面板高精度模拟的前提下提高计算效率是一个亟待解决的难题。通过引入背景网格线及径向插值函数(RPIM),开发了基于无网格的界面模拟方法,实现了界面两侧节点自由分布,克服了Goodman单元点对点的限制。该方法可灵活地连接两侧不同尺寸的面板及堆石体网格,进而建立面板与垫层跨尺度分析模型。同时采用"面向对象"及"超单元"技术将该方法集成到自主开发的GEODYNA计算平台中,实现了与传统有限元法的无缝耦合,并可应用界面弹塑性本构模型模拟堆石和面板复杂的接触关系。在此基础上,通过引入虚节点进一步提高了径向插值函数(RPIM)在边界附近的模拟精度。研究表明,基于无网格的非点对点界面模拟方法可高效、灵活地实现面板坝跨尺度分析,在保证高精度的前提下大幅度降低自由度和提高计算效率。本文研究方法可以很容易地扩充到三维问题,并为面板坝面板精细化损伤演化分析提供有力的技术手段。The concrete face is the core of anti-seepage structure in concrete-face rockfill dam(CFRD)and its safety is of great importance. While,the dimensions vary significantly between anti-seepage face slab and rock-fill body,and it has been an urgent and tough problem to maintain the high simulation precision and increase the calculation efficiency. In this paper,through introduce the background mesh line and radial interpolation function(RPIM),a novel approach for simulating the interface based on meshless method is developed,which achieve the flexible nodal distribution along each surface of interface and overcome the node-to-node restrictions in traditional Goodman element. This method can connect the meshes with different size in face slab and rock-fill zone directly,thus a cross-scale model between face slab and cushion zone is established. Meanwhile,based on‘object-oriented’and‘super element’technologies the meshfree interface is integrated into the self-developed software platform GEODYNA, which can directly couple with finite element method(FEM) and adopt the elastic-plastic constitutive models to capture the complex behaviors within interface zone. In addition,via introducing the virtual nodes,the simulation precision of RPIM near the boundary obtains a further improvement. The computation results indicate that the non-matching nodes interface based on meshfree method can easily achieve cross-scale model in CFRD,which can obviously improve the calculation efficiency and maintain the high precision of delicate analysis.This research can extend to three dimensions and provide an effective tool for the damage evolution analysis of concrete face slab.

关 键 词：非点对点界面 无网格法 跨尺度分析 RPIM 面板堆石坝 

分 类 号：TV641.4[水利工程—水利水电工程]