Matrix Analysis of Variable Cross-Section Curved Beam Elements Based on Energy Method
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摘要:
为得到2节点6自由度显式变截面曲梁单元刚度矩阵的解析解公式,将变截面曲梁单元纳入常用杆系结构有限元系统. 基于卡氏第二定理推导变截面空间曲梁单元刚度矩阵,利用弹性体的势能驻值原理推导变截面曲梁单元柔度矩阵;通过逆运算得到变截面曲梁单元悬臂端刚度矩阵;根据静力平衡条件与虚功原理获得整体变截面曲梁单元刚度矩阵,且本文变截面曲梁单元有限元列式可退化为等截面等曲率梁单元列式及等截面直线梁单元标准列式;利用MATLAB编制变截面曲线梁桥的静力计算程序,并和ANSYS实体有限元模型对比,验证变截面曲梁静力分析理论. 研究结果表明:本文理论基于有限元理论分析了变截面曲梁的弯扭耦合,变截面曲梁理论与ANSYS实体有限元模型挠度最大误差为3.72%,与ANSYS梁单元模型最大误差不足0.5%;变截面曲梁理论退化后的变截面直梁与ANSYS实体有限元梁模型挠度最大误差为1.72%,与ANSYS梁单元模型最大误差不足0.1%.
Abstract:To obtain the analytical solution formula of the stiffness matrix of a 2-node 6-degree-of-freedom explicit variable cross-section curved beam element, the variable cross-section curved beam element was incorporated into the widely used finite element system of rod structures. Based on Castigliano’s second theorem, the stiffness matrix of the spatial variable cross-section curved beam element was derived, and the flexibility matrix of the variable cross-section curved beam element was deduced by using the principle of stationary potential energy of elastic bodies; then, the cantilever end stiffness matrix of the variable cross-section curved beam element was obtained through inverse calculation. According to the static equilibrium condition and the principle of virtual work, the element stiffness matrix of the overall variable cross-section curved beam was obtained. In addition, the finite element formulation of the variable cross-section curved beam element could be degenerated into the formulation of uniform cross-section and uniform curvature beam elements and the standard formulation of uniform cross-section straight beam elements. A static calculation program for variable cross-section curved beam bridges was developed using MATLAB, and it was compared with the ANSYS solid finite element model to verify the static analysis theory of variable cross-section curved beams. The results indicate that the developed theory analyzes the bending-torsion coupling of the variable cross-section curved beam based on the finite element theory. The maximum deflection error between the variable cross-section curved beam theory and the ANSYS solid finite element model is 3.72%, and the maximum error compared with the ANSYS beam element model is less than 0.5%; furthermore, the maximum deflection error between the variable cross-section straight beam degenerated from the developed theory and the ANSYS solid finite element beam model is 1.72%, and the maximum error compared with the ANSYS beam element model is less than 0.1%.
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[1] 孙广华. 曲线梁桥计算[M]. 北京: 人民交通出版社, 1995. [2] 于香杰, 游斌弟, 魏承, 等. 中性线修正型变截面梁类构件压电控制[J]. 力学学报, 2022, 54(1): 209-219.Yu Xiangjie, You Bindi, Wei Cheng, et al. Piezoelectric control investigation on beam with variable crosssection and correctional neutral line[J]. Chinese Journal of Theoretical and Applied Mechanics, 2022, 54(1): 209-219. [3] Wei G Q, Lardeur P, Druesne F. Free vibration analysis of thin to thick straight or curved beams by a solid-3D beam finite element method[J]. Thin-Walled Structures, 2023, 191: 111028.1-111028.16. doi: 10.1016/j.tws.2023.111028 [4] Deng L F, Niu M Q, Xue J, et al. A two-dimensional corotational curved beam element for dynamic analysis of curved viscoelastic beams with large deformations and rotations[J]. International Journal for Numerical Methods in Engineering, 2023, 124(7): 1564-1584. doi: 10.1002/nme.7175 [5] Horák M, La M R E, Jirásek M. Efficient formulation of a two-noded geometrically exact curved beam element[J]. International Journal for Numerical Methods in Engineering, 2023, 124(3): 570-619. doi: 10.1002/nme.7133 [6] 周文鑫, 周叮, 张建东, 等. 多跨高墩变截面梁桥的动力学特性研究[J]. 振动与冲击, 2021, 40(16): 111-117, 182. doi: 10.13465/j.cnki.jvs.2021.16.014Zhou Wenxin, Zhou Ding, Zhang Jiandong, et al. Dynamic characteristics of a multi-span high-pier bridge with variable cross-sections[J]. Journal of Vibration and Shock, 2021, 40(16): 111-117,182. doi: 10.13465/j.cnki.jvs.2021.16.014 [7] 吴鸿庆, 任侠. 结构有限元分析[M]. 北京: 中国铁道出版社, 2000. [8] Wang T M, Merrill T F. Stiffness coefficients of noncircular curved beams[J]. Journal of Structural Engineering, 1988, 114(7): 1689-1699. doi: 10.1061/(ASCE)0733-9445(1988)114:7(1689) [9] 陈代海, 周帅, 李银鑫, 等. 变截面梁单元刚度矩阵的推导及影响因素分析[J]. 中外公路, 2022, 42(2): 100-106.Chen Daihai, Zhou Shuai, Li Yinxin, et al. Derivation for stiffness matrix of beam element with variable cross-section and analysis of influnecing factors[J]. Journal of China & Foreign Highway, 2022, 42(2): 100-106. [10] 王勖成. 有限单元法[M]. 北京: 清华大学出版社, 2003. [11] 刘磊, 许克宾. 曲杆结构非线性分析中的直梁单元和曲梁单元[J]. 铁道学报, 2001, 23(6): 72-76.Liu Lei, Xu Kebin. Curved-beam element and straight-beam element used in the nonlinear analysis of curved frame structures[J]. Journal of the China Railway Society, 2001, 23(6): 72-76. [12] 传光红, 陈以一, 童根树. 变截面Timoshenko梁的单元刚度矩阵[J]. 计算力学学报, 2014, 31(2): 265-272. doi: 10.7511/jslx201402021Chuan Guanghong, Chen Yiyi, Tong Genshu. Element stiffness matrix for Timoshenko beam with variable cross-section[J]. Chinese Journal of Computational Mechanics, 2014, 31(2): 265-272. doi: 10.7511/jslx201402021 [13] Kapania R K, LI J. A formulation and implementation of geometrically exact curved beam elements incorporating finite strains and finite rotations[J]. Computational Mechanics, 2003, 30(5): 444-459. [14] 齐东春, 沈锐利, 刘章军, 等. 悬索桥有限元计算的三节点空间鞍座单元[J]. 西南交通大学学报, 2014, 49(6): 942-947. doi: 10.3969/j.issn.0258-2724.2014.06.002Qi Dongchun, Shen Ruili, Liu Zhangjun, et al. 3-node sptial saddle element for finite element calculation of suspension bridge[J]. Journal of Southwest Jiaotong University, 2014, 49(6): 942-947. doi: 10.3969/j.issn.0258-2724.2014.06.002 [15] Cazzani A, Malagù M, Turco E. Isogeometric analysis of plane-curved beams[J]. Mathematics and Mechanics of Solids, 2016, 21(5): 562-577. doi: 10.1177/1081286514531265 [16] Li W X, Ma H T, Gao W. Geometrically exact curved beam element using internal force field defined in deformed configuration[J]. International Journal of Non-Linear Mechanics, 2017, 89: 116-126. doi: 10.1016/j.ijnonlinmec.2016.12.008 [17] 董长军, 刘世忠, 李爱军. 变曲率曲线梁的单元刚度矩阵分析[J]. 西南交通大学学报, 2017, 52(3): 474-481. doi: 10.3969/j.issn.0258-2724.2017.03.006Dong Changjun, Liu Shizhong, Li Aijun. Element stiffness matrix analysis for variable curvature curved beam[J]. Journal of Southwest Jiaotong University, 2017, 52(3): 474-481. doi: 10.3969/j.issn.0258-2724.2017.03.006 [18] Tang Y Q, Du E F, Wang J Q, et al. A co-rotational curved beam element for geometrically nonlinear analysis of framed structures[J]. Structures, 2020, 27: 1202-1208. doi: 10.1016/j.istruc.2020.07.030 [19] 孙训方, 方孝淑, 关来泰. 材料力学[M]. 北京: 高等教育出版社, 2019. [20] 中交公路规划设计院有限公司. 《公路桥涵设计通用规范》: JTG D60—2015[M]. 北京: 人民交通出版社, 2015. -
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