【作者】 孙治国；

【导师】 司炳君；

【作者基本信息】 大连理工大学 ， 结构工程， 2006， 硕士

【摘要】 ANSYS软件在混凝土结构有限元分析中具有很大的实用性和方便性,Solid65单元是ANSYS软件中专门为分析混凝土结构定义的单元,国内外利用Solid65单元对混凝土结构进行了大量的有限元模拟分析并取得了一定的进展。本文在总结国内外研究工作的基础上,以桥梁结构现场静载试验和实验室试验结果为依据,建立了针对于桥梁上部结构(无粘结预应力混凝土梁)和下部结构(桥墩)的有限元计算模型,进行了桥梁结构极限承载力和滞回特性的研究工作,具体包括以下内容: 1、综述了国内外利用Solid65单元分析钢筋混凝土结构、钢—混凝土组合结构和FRP加固混凝土结构取得的进展,总结了Solid65单元的使用方法及应该注意的事项。结合2根钢筋混凝土简支梁抗弯试验,具体讨论了利用ANSYS软件分析混凝土结构极限承载力的若干技术细节。 2、为了对桥梁工程中的无粘结预应力混凝土箱型梁的承载能力做出正确评价,利用ANSYS软件建立了无粘结预应力混凝土箱型梁的有限元计算模型,并分别对两个工程实例梁的承载力进行数值分析,为其承载能力的评定提供有效依据。 3、建立了无粘结预应力混凝土连续梁的有限元计算模型,在验证了计算模型正确性的基础上,利用有限元方法分析了无粘结预应力混凝土连续梁在单跨集中荷载和两跨对称集中荷载下的承载性能。 4、基于钢筋混凝土桥墩低周反复荷载试验结果,建立了钢筋混凝土桥墩的有限元计算模型,并分别进行了单调加载和低周反复荷载下全过程的非线性有限元分析,将计算结果与试验结果进行对比,讨论了不同的混凝土强化模型、本构关系和有限元求解方法对计算结果的影响。总体来看,建立的有限元模型可以较好的模拟桥墩的荷载—位移曲线、极限承载力以及桥墩在不同受力阶段的破坏形态,且计算结果对剪力传递系数、混凝土强化法则和本构关系的选取并不敏感,但它们会影响计算的收敛性。更多还原

【Abstract】 The ANSYS software is practicable and convenient in finite element analysis of concrete structures and Solid65 element is defined for concrete material specially in ANSYS software. Much finite element analysis of concrete structures by Solid65 element has been carried out and certain progress has been made.The research progress of analyses concrete structure by ANSYS software is summarized and finite element model for superstructure(unbonded prestressed concrete beam)and substructure(bridge piers) of bridge are established based on the field static load test and laboratory experiment results.Then, research on ultimate bearing capacity and hysteretic behavior of bridge structures is carried out.The main contents of this paper are summarized as follows:1 .The research progress in analysis of RC structures, steel-concrete composite structures and FRP-strengthened concrete structures by using Solid65 element are reviewed.The methods of how to use this element and some matters needing attention are summarized. Then,some details of analysis ultimate bearing capacity of concrete structure by using ANSYS software are discussed based on the bending test results of two simply supported beams.2. In order to evaluate correctly the bearing capacity of unbonded prestressed concrete box girder in bridge engineering, a finite element model for unbonded prestressed concrete box girder is presented. Then the bearing capacity of two box girders in engineering are analyzed respectively by using ANSYS software,which provide effective basis for evaluation of the bearing capacity of the two box girders.3.A finite element model for unbonded prestressed concrete continuous beams is presented and the model proved correctly.Then,the bearing capacity of continuous beams under single-span loading or two-span symmetric loading is studied by finite element method.4.Based on the low-cycle reversed loading test results,three RC bridge piers are modeled with ANSYS software and the tests are non-linearly simulated respectively under monotonic or cyclic loading.The calculated results are compared with experimental ones.The influences of hardening model and constitutive relations of concrete and solution method on the calculated results are discussed. In general, the simulated load-deformation curves, ultimate loads and failure mode of the bridge piers are corresponding well with experimental results.Also, The calculated results are not sensitive to the shear retention coefficients,hardening model and constitutive relations of the concrete,but the convergence rate will be influenced.更多还原