一种集中塑性铰模型算法研究及实现

Research and Implementation of a Lumped Plastic Hinge Model Algorithm

摘要:

集中塑性铰模型常用来模拟梁柱单元的非线性，但具有多种实现算法。基于有限单元柔度法提出的集中塑性铰单元模型是在无刚体位移系统下，根据弹性梁单元处和塑性铰处截面与变形的关系，通过理论及算法的推导，并在基于面向对象的有限元程序求解框架中加以实现的。为验证该单元模型的准确性和可靠性，采用此模型对典型案例进行了非线性分析，并分别将分析结果、商用软件SAP2000和MIDAS模拟值与理论值进行了横向位移和转角的对比。结果表明，该单元模型建模方便、算法简单，易于集成到有限元分析程序中，能够与普通梁单元共同组成构件，可用来分析桥墩、框架梁柱等的非线性问题。

Abstract:

The lumped plastic hinge model is often used to simulate the nonlinearity of beam-columns elements, but there are many realization algorithms for it. The lumped plastic hinge element model proposed based on the finite element flexibility method is in a system without rigid body displacement. The theory and algorithm are derived according to the relation between the section and the deformation at the elastic beam element and the plastic hinge, and are implemented in the framework of object-oriented finite element program solution. To verify the accuracy and reliability of this element model, a nonlinear analysis of typical cases is conducted using this model. And the analysis results, the simulated values of commercial software SAP2000 and MIDAS are compared with the theoretical values for lateral displacement and rotation angle respectively. The result shows that this element model is convenient to model and has a simple algorithm, which is easy to integrate into the finite element analysis program and can be used together with ordinary beam elements to form components, and can be used to analyze the nonlinear problems of bridge piers, frame beams and columns.