基于显式算法的纤维梁柱单元模型  

EXPLICIT ALGORITHM-BASED FIBER BEAM-COLUMN ELEMENT MODEL

作　　者：禚一[1,2] 李忠献[1,2] 

机构地区：[1]天津大学建筑工程学院,天津300072 [2]滨海土木工程结构与安全教育部重点实验室(天津大学),天津300072

出　　处：《工程力学》2011年第12期39-44,共6页Engineering Mechanics

基　　金：国家自然科学基金重大研究计划重点支持项目(90715032);国家自然科学基金重大国际合作项目(51021140003);国家自然科学基金重大研究计划培育项目(91015005)

摘　　要：为精细模拟钢筋混凝土桥梁的强非线性行为,利用显式中心差分法,建立一种基于显式算法的纤维梁柱单元模型,并引入到前期建立的纤维梁柱单元实用模拟平台FENAP中。采用该显式单元模型,分别对一钢悬臂梁进行滞回特性分析和对一钢筋混凝土桥墩进行推覆分析,并将计算结果与采用FENAP隐式单元模型和采用OpenSEES软件纤维模型的计算结果进行对比分析。结果表明,所建立的FENAP显式纤维梁柱单元模型可有效模拟材料软化行为,避免由结构负刚度所引起的不收敛,且计算精度较高,为长大桥梁结构倒塌分析提供了一种实用手段。In order to simulate the strong nonlinear behavior of RC bridges precisely,an explicit algorithm-based fiber beam-column element model is constructed using the explicit central difference method and introduced into the FENAP platform built previously.The hysteretic analysis of a steel cantilever beam and the pushover analysis of a RC bridge pier are performed respectively using the explicit fiber beam-column element,and the calculated results are compared with that using the implicit fiber beam-column element of FENAP and the fiber element of OpenSEES.It is indicated that the material softening behavior may be simulated effectively and the nonconvergence due to structural negative-stiffness may be avoided with high precision using the proposed explicit fiber beam-column element model which provides a practical tool for the collapse analysis of large bridges.

关 键 词：钢筋混凝土桥梁 非线性行为 纤维梁柱单元 显式算法 材料软化 结构负刚度 

分 类 号：TU352[建筑科学—结构工程]