多高层钢-混凝土组合框架结构体系弹塑性分析模型

以通用有限元软件MSC.MARC (2005r2)为平台，建立了纤维梁单元和分层壳单元的混合有限元模型，用于完全剪力连接多高层钢-混凝土组合框架在竖向荷载和单调水平荷载作用下的整体弹塑性分析，并得到试验和算例验证。给出了钢梁、钢柱以及混凝土楼板的有限元建模方法以及相关参数的取值建议，并就楼板和钢梁的协同工作以及半刚性梁柱节点在模型中的实现展开讨论。算例表明：节点半刚性和楼板的空间作用是影响结构性能的关键因素，而已有的相关模型并未同时解决这一问题。建议的模型忽略了钢梁与混凝土楼板之间的滑移效应，算例表明滑移效应对结构体系的整体计算结果影响不大，但能有效简化建模，提高计算效率。图23表2参31

Model for elasto-plastic analysis of multistory and highrise steel-concrete composite frame systems

This paper presents a mixed finite-element model combining the fibered beam element and the layered shell element using the general finite-element program MSC.MARC (2005r2) for global elasto-plastic analysis of multistory and highrise structures with fully shear connected steel-concrete composite frames subjected to the combined action of gravity and monotonic lateral loads. The model was verified by a number of tests and numerical examples. Modeling details of the steel beam, the steel column and the reinforced concrete (RC) slab were suggested and the realization of beam-slab compatibility and beam-column semirigidity were discussed. According to the calculation results, the beam-column semirigidity and the slab space effect are the two critical factors influencing the structural behavior, but these two factors haven’t been considered simultaneously in some previous models. Since the slip effect between the steel beam and the concrete slab exerts negligible influence on the global calculation results of the structural system verified by the test results, the model in this paper has neglected the slip effect in order to simplify the modeling procedure and enhance the calculating efficiency.