基于CR列式的平面体外预应力梁非线性有限元模型  

Nonlinear Finite Element Model of Plane Externally Prestressed Beam Based on Co-rotational Formulation

作　　者：邓继华 杨倩 陈历强 谭平[3] 田仲初 DENG Jihua;YANG Qian;CHEN Liqiang;TAN Ping;TIAN Zhongchu(School of Civil Engineering,Changsha University of Science and Technology,Changsha 410114,China;Key Laboratory of Safety Control of Bridge Engineering of Ministry of Education(Changsha University of Science and Technology),Changsha 410114,China;Earthquake Engineering Research&Test Center,Guangzhou University,Guangzhou 510405,China)

机构地区：[1]长沙理工大学土木工程学院,湖南长沙410114 [2]桥梁工程安全控制教育部重点实验室(长沙理工大学),湖南长沙410114 [3]广州大学工程抗震研究中心,广东广州510405

出　　处：《湖南大学学报（自然科学版）》2023年第3期62-70,共9页Journal of Hunan University:Natural Sciences

基　　金：国家自然科学基金资助项目(52278142);广东省自然科学基金资助项目(2015A030310141);湖南省教育厅重点科学研究项目(21A0187);长沙理工大学土木工程重点学科基金项目(17ZDXK03);桥梁结构健康与安全国家重点实验室开放基金项目(BHSKL21-06-GF)。

摘　　要：将体外预应力筋视为在锚固位置和转向块位置分别与梁体固结及相连的常应变构件,基于锚固位置和转向块位置处体外预应力筋和梁体的几何关系,采用共旋坐标(co-rotational,CR)法导出体外预应力筋在结构坐标系中的切线刚度矩阵和杆端抗力.结合常规的几何非线性CR平面梁单元,建立体外预应力平面梁的几何非线性有限元模型并编制了程序,对一简支梁算例的两个工况进行了几何非线性分析并与ABAQUS程序进行了比较.结果表明:不管是预应力施加工况还是承受外载工况,对于梁端水平位移、跨中竖向位移和体外筋轴力,两种方法得到的计算结果吻合良好,从体外筋轴力方面而言,本文方法更能体现体外筋为常应变构件的受力性能,因此可用于体外预应力结构的非线性有限元分析.The external prestressed tendon is regarded as a constant strain member consolidated and connected with the beam at the anchorages and the deviators,respectively.Based on the geometric relationship of the external prestressed tendon and beam body at the anchorages and the deviators,the tangent stiffness matrix and resistance of the tendon end in the structural coordinate system are derived by the co-rotational(CR)method.Combined with the conventional CR plane beam element,a geometric nonlinear finite element model is established and the program is compiled.The geometric nonlinear analysis of the example in two cases is carried out and compared with results ob⁃tained by ABAQUS.The results show that the beam-ends horizontal displacement,the middle-span vertical dis⁃placement and the axial force of the external tendon calculated by the two methods are in good agreement,for both prestress application state and load application state.For the axial force of the external tendon,the proposed method can better reflect the mechanical performance of the external tendon as a constant strain member,which can be used for the nonlinear finite element analysis of the externally prestressed structure.

关 键 词：体外预应力筋 几何非线性 有限元 切线刚度矩阵 CR法 

分 类 号：TU378.2[建筑科学—结构工程]