三维混凝土Cap模型在OpenSees中的实现

Abstract

综述了由HOfSTETTEr g和SIMOn J C提出的经典三维混凝土非光滑多屈服面塑性本构模型,即CAP模型,详述了此模型的算法和流程,并将此模型在通用非线性有限元软件OPEnSEES中编程实现。对CAP模型上每个作用区域使用最近点投影法计算得到其应力,并计算得到此模型的一致切线模量。将CAP模型应用于一个二维混凝土重力坝非线性动力响应分析,验证了此模型的稳定性和工程实用性。CAP模型的实现,将OPEnSEES功能拓展到三维混凝土结构的数值分析中,拓展了OPEnSEES的计算能力和分析功能,使其可用于混凝土重力坝等大型水利工程结构的非线性动力计算分析。

This paper reviews an existing classical three dimensional(3D)nonsmooth multi-yield surface plasticity concrete model proposed by Hofstetter and Simon,i.e.the Cap model,details its algorithm and calculation flowchart and implements it into OpenSees,ageneral nonlinear finite element analysis software.The model uses a closest point projection method to compute the stress in each region defined by the yield surfaces,and computes the consistent tangent modulus.As an illustration application example,the paper analyzes the nonlinear dynamic responses of a two-dimensional concrete gravity dam by using this newly implemented Cap model,and verifies the stablity and applicability of the model.The implementation of cap model extends OpenSees′capability to modelling 3Dconcrete structures,so that it can be used to analyze the large-scale hydraulic engineering,e.g.,nonlinear dynamic analysis of concrete gravity dam.