钢支撑滞回曲线的模拟方法

Simulation methods for hysteretic curve of steel braces

钢支撑滞回曲线主要有三种模拟方法:现象描述法、有限元法和塑性铰法。在分析了各模拟方法优劣的基础上,提出一种新型的基于现象描述法的支撑模型。该模型通过一系列控制参数来包络钢支撑复杂的滞回曲线,并根据已有的同类型支撑试验结果标定控制参数。研究表明,该模型具有较高的模拟精度及计算效率,解决了早期基于现象描述法支撑模型模拟结果较为粗糙的问题。此外,为研究通用性更高的支撑模型,还提出了一种纤维支撑模型。该模型在跨中引入初始几何缺陷以模拟钢支撑的屈曲及屈曲后滞回特性,模型参数仅涉及支撑的几何及材料特性而易于确定。分析表明,该模型能满足多尺度整体结构分析的精度要求。两种模拟方法可应用于带支撑结构的地震反应分析和设计。

Three simulation methods for hysteretic curve of steel braces,including phenomenological description method,finite element method and plastic-hinge method,were reviewed.A new brace model based on phenomenological description method was proposed.This model contains a series of governing variables to envelop the complicated hysteretic curve of steel braces and the governing variables can be calibrated by available test results.Simulation results of some available test data prove that this model is more accurate and proficient than those previous brace models based on phenomenological description method.Furthermore,in order to study a more generous brace model,a fiber brace model was demonstrated as well.In this model,certain geometric initial imperfection in the middle of a brace is required to simulate its buckling and post buckling hysteretic characters.The variables of the model are only geometry and material characters of the brace and can be easily determined.The analytical results show that the fiber brace model is precise enough to carry out integral structure analysis under multi-scale requirement.The proposed two models can be used in analysis and design of a structure system containing braces under earthquake excitation.