半平面问题远域辐射阻尼的时域边界元法模拟研究  

Simulation of the far-field radiation damping for half-plane problem by time domain boundary element method

作　　者：张梅[1] 唐波 李宏军 郝文秀[1] 龚海天 ZHANG Mei;TANG Bo;LI Hong-jun;HAO Wen-xiu;GONG Hai-tian(Urban and Rural Construction Institute,Hebei Agricultural University,Baoding 071001,China;Shanghai Strong Foundation Engineering Co.,Ltd.,Shanghai 200233,China;Shimizu Corporation Singapore,Singapore 339509,Singapore)

机构地区：[1]河北农业大学城乡建设学院,保定071001 [2]上海强劲地基工程股份有限公司,上海200233 [3]新加坡清水建设株式会社,新加坡339509

出　　处：《计算力学学报》2021年第2期173-179,共7页Chinese Journal of Computational Mechanics

基　　金：河北省高等学校科学技术研究(QN2020135)资助项目.

摘　　要：辐射阻尼在岩石基坑爆破开挖、边坡稳定、结构抗震以及结构-地基动力相互作用等实际工程问题中具有重要意义。为了模拟半平面问题的远域辐射阻尼,以时域边界元法(TD-BEM)理论为基础,根据应力波在弹性介质中的传播特性,在时域内提出了一种新的单元,即自适应半无限边界单元,专门用于离散远域半无限边界。该单元外侧节点是一个始终处于应力波波前位置的动态节点,保证计算区域在任何情况下都恰好包含应力波的影响范围,从而模拟远域辐射阻尼。最后,分别采用近场和远场动力荷载作用下的弹性半平面算例进行验证,并将结果与有限元法FEM和常规TD-BEM结果进行综合对比。结果表明,采用自适应半无限单元的TD-BEM满足半无限域的辐射条件,较好地解决了远域辐射阻尼的模拟问题,且在计算时间成本与常规TD-BEM几乎相同的前提下,具有更高的计算精度。The radiation damping is of great significance in practical engineering such as blasting excavation of rock foundation pit,slope stability,structural seismic and structure-ground dynamic interaction.In order to simulate the far-field radiation damping of the half-plane problem,a new kind of element,adaptive semi-infinite boundary element,is proposed in the time domain based on the theory of the time domain boundary element method(TD-BEM)and the propagation characteristics of stress wave in elastic medium,which is specially used for discrete far-field semi-infinite boundary.The outer node of the element is always in front of the stress wave,which ensures that the calculation field can exactly contain the influence range of the stress wave in any case,so as to simulate the far-field radiation damping.Finally,two elastic half-plane examples under far-field and near-field dynamic loading respectively are used for verification,and the results are compared with those of the finite element method(FEM)and the original TD-BEM.The results show that the semi-infinite radiation condition is satisfied and far-field radiation damping can be simulated well by the TD-BEM adopted by the adaptive semi-infinite boundary element,and a higher accuracy can be obtained than the original TD-BEM under the almost same time cost.

关 键 词：辐射阻尼 自适应半无限边界单元 时域边界元法 半平面问题 应力波 

分 类 号：O343.1[理学—固体力学] O242.1[理学—力学]