基于GPU并行计算的地下结构非线性动力分析软件平台开发

为解决地下结构隐式非线性动力分析收敛性差和计算效率低的技术瓶颈，该文建立了基于GPU并行计算的地下结构显式动力分析软件平台。在此平台中提出并实现了一种混凝土弥散开裂模型；给出并实现了一种钢筋纤维与实体单元的耦合方法；基于等参元思想，提出了人工边界节点的单元从属面积的计算方法；为实现节点不协调情况下的土与结构相互作用分析，开发实现了一种实体单元间的两节点接触单元。利用该文开发的软件对日本大开地铁站进行了重力场分析、线性和非线性动力分析。将重力场和线性动力分析结果与ABAQUS分析结果进行了对比，结果表明该文软件计算结果与ABAQUS计算结果一致，且计算效率约为ABAQUS计算效率的5.68倍，验证了软件各模块的正确性和效率。另外，通过将非线性计算结果与灾害调查结果进行对比分析，验证了软件非线性分析的稳定性和合理性。

DEVELOPMENT ON SOFTWARE PLATFORM FOR NONLINEAR DYNAMIC ANALYSIS OF UNDERGROUND STRUCTURE BASED ON GPU PARALLEL COMPUTING

The implicit nonlinear dynamic analysis of underground structures is of poor convergence and low computational efficiency.Based on GPU parallel computing,a software platform for the explicit dynamic analysis of underground structures was established,which can solve the technical bottleneck of the implicit method.In this platform,a smeared crack model for concrete was proposed and implemented.A coupling method for rebar fibers and solid elements was developed and implemented.Based on the isoparametric element idea,a method for calculating the element area of artificial boundary nodes was proposed.A two-node interface element for solid elements was proposed to perform the interaction analysis between soil and structure with uncoordinated nodes.The gravity field analysis,linear and nonlinear dynamic analysis of Daikai subway station in Japan were performed by the software.The results of gravity field analysis and linear dynamic analysis were compared with the results of ABAQUS.The results of the software were in an agreement with the results of ABAQUS,and the computational efficiency was about 5.68 times the efficiency of ABAQUS.Thusly,the accuracy and efficiency of the software modules were verified.Besides,the stability and rationality of the software nonlinear analysis were verified by comparing the results of nonlinear analysis with the disaster investigation.