摘要
目的为使离散单元法能够适用于钢筋混凝土梁柱构件在往复荷载作用下的非线性分析.方法在离散单元法中杆段多弹簧模型的基础上,提出了杆段纤维模型.该模型将梁柱构件划分为若干刚体单元,相邻单元间由多个混凝土与钢筋轴向纤维组成的纤维束连接.并建立单元位移与纤维变形、纤维内力与单元约束力之间的变换矩阵,以形成单元与纤维束的力-位移关系.混凝土与钢筋轴向纤维,分别采用相应材料的单轴应力-应变本构模型.并开发了基于杆段纤维模型的钢筋混凝土结构非线性分析程序DEM-COLLAPSE.对钢筋混凝土柱进行算例分析,并与有限元分析结果进行对比.结果实现了将杆段纤维模型用于低周往复荷载作用下钢筋混凝土柱的非线性性能模拟.杆段纤维模型的计算结果与有限元模拟结果及试验结果均较为吻合.杆段纤维模型中纤维数量对计算结果影响较小,截面纤维束划分方式取5×5或7×7较为合理.结论笔者提出的杆段纤维模型使得离散单元法能够模拟钢筋混凝土梁柱构件在断裂破坏前的非线性性能,并具有与有限单元法相近的计算精度,拓展了离散单元法的应用范围与计算能力.
In order to analyze the nonlinear performance of RC beam-column member under cyclic loading,the segment-fiber model(SFM)is proposed based on the segment-multi-spring model in Discrete Element Method(DEM).Beam-column member are divided in to several rigid elements,and the adjacent elements are connected by the fiber assembly.The fiber assembly is composed of concrete fibers and steel fibers.The transformation matrix between element displacement and fiber deformation,as well as fiber force and element binding force,is established to form the force-displacement relationship between element and fiber assembly.The uniaxial constitutive models of concrete and steel are respectively used on concrete fibers and steel fibers.Accordingly,a nonlinear analysis program named as DEM-COLLAPSE has been developed.Two RC columns under low cyclic loading have been simulated by DEM-COLLAPSE.The calculated results agree well with the results of the FEM and the test results.The number of fibers in SFM has little influence on the calculation results,and it is reasonable to choose 5×5 or 7×7 as the fiber division mode.The SFM can be applied to simulate the nonlinear performance of RC beam-column members,and the application range of DEM is greatly expanded.
作者
王强
路炯
侯康康
郝露露
WANG Qiang;LU Jiong;HOU Kangkang;HAO Lulu(School of Civil Engineering,Shenyang Jianzhu University,Shenyang,China,110168;Shanghai Zhongsen Architectural and Engineering Design Consultants Limited Company,Shanghai,China,200333)
出处
《沈阳建筑大学学报（自然科学版）》
CAS
CSCD
北大核心
2020年第1期38-47,共10页
Journal of Shenyang Jianzhu University：Natural Science
基金
国家自然科学基金项目(51178279)
沈阳市科技计划项目(F16-175-9-00)
