基于薄层单元的黏弹性人工边界的模拟  

Simulation of Viscoelastic Artificial Boundary Based on Thin Layer Element

作　　者：侯恒 杨杰[1] 程琳[1,2] 吕高 马春辉 HOU Heng;YANG Jie;CHENG Lin;Lü Gao;MA Chun-hui(College of Water Conservancy and Hydropower,Xi’an University of Technology,Xi’an 710048,China;State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,Hohai University,Nanjing 210098,China)

机构地区：[1]西安理工大学水利水电学院,西安710048 [2]河海大学水文水资源与水利水电工程科学国家重点实验室,南京210098

出　　处：《长江科学院院报》2020年第2期164-169,共6页Journal of Changjiang River Scientific Research Institute

基　　金：国家自然科学基金项目(51409205,51579085)。

摘　　要：为了解决黏弹性人工边界在实际应用过程中前处理时间长、不易实现等不足之处,提出了基于薄层单元的黏弹性人工边界的模拟方法。利用单元矩阵等效原理,采用薄层单元构造了等效黏弹性边界单元,并通过在大型通用有限元软件MSC Marc中设置等效黏弹性边界单元的参数属性,实现了黏弹性人工边界的模拟。三维均匀弹性半空间算例和某混凝土重力坝工程实例结果表明:采用等效黏弹性边界单元得到的计算结果与理论解、基于黏弹性人工边界的计算值非常相近,相对误差不超过1%。因此,采用薄层单元的模拟的黏弹性人工边界具有足够的精度,且施加方便,这为实际工程进行抗震分析提供了简便且精确的方法。In practical application,viscoelastic artificial boundary is featured with such defects as long preprocessing and difficulty of implementation.In view of this,a method of simulating viscoelastic artificial boundary based on thin layer element is proposed.Equivalent viscoelastic boundary element composing thin layer is constructed in light of the principle of element matrix equivalence.By setting the parameter attributes of the equivalent viscoelastic boundary element in finite element software MSC MARC,the artificial viscoelastic boundary can be simulated.A computation example of three-dimensional uniform elastic semi-space and a practical engineering example of concrete gravity dam demonstrate that the calculated results obtained by using the equivalent viscoelastic boundary element are very close to the theoretical solution and the calculated values based on the viscoelastic artificial boundary,with the relative error smaller than 1%.Therefore,the simulated viscoelastic artificial boundary using thin-layer elements has sufficient accuracy and is easy to apply,thus providing a simple and accurate method for seismic analysis in practical engineering.

关 键 词：薄层单元 刚度矩阵 阻尼矩阵 黏弹性人工边界 动力响应 

分 类 号：TV31[水利工程—水工结构工程]