地震工程学报2018，Vol.40Issue(2)：376-383,8.DOI:10.3969/j.issn.1000-0844.2018.02.376
基于能量最小化原理的弹性波CT成像频域有限元反演算法
FEM Inversion Algorithm in Frequency Domain for Elastic Wave CT Based on Energy Minimization Principles
薛龙 1刘天云 1张建民1
作者信息
- 1. 清华大学 水沙科学与水利水电工程国家重点实验室/土木水利学院,北京100084
- 折叠
摘要
Abstract
In element and model tests,high-accuracy measurement for the internal displacement field of a sample is crucial in investigating the mechanical property of the material under loading. In this study,a frequency-domain finite element method based on the energy minimization princi-ple is developed for elastic wave CT.Through solving the wave equation numerically,the dis-placement fields are estimated and then compared with their actual values.Thus,the renewal gradients of the parameters of every element are obtained,including the density (ρ)and the Lame constant (λ).Furthermore,the distribution of density (ρ)and the Lame constant (λ)can be acquired upon several iterations.The new method can avoid solving the Jacobi matrix,leading to a great improvement in calculation efficiency.In addition,the numerical inversion iteration of the Lame constant (λ)shows high efficiency and accuracy when the whole displacement field is known,and the efficiency and accuracy gradually decrease with an increased number of unknown displacement nodes.关键词
反演算法/能量最小化原理/有限元/弹性波Key words
inversion algorithm/energy minimization principle/finite element method (FEM)/elastic wave分类
建筑与水利引用本文复制引用
薛龙,刘天云,张建民..基于能量最小化原理的弹性波CT成像频域有限元反演算法[J].地震工程学报,2018,40(2):376-383,8.
