装配式桥梁预制空心桥墩与承台连接性能的研究与应用

发布时间：2018-05-04 21:31

本文选题：装配式桥梁 + 预制空心桥墩　；参考：《合肥工业大学》2017年硕士论文

【摘要】：我国桥梁建设桥墩施工大多采用现浇混凝土施工工艺,这种传统施工方法现场湿作业多,施工周期长,对周围环境的影响大,与建筑工业化和绿色施工的要求不相符合。为了应对现浇混凝土施工的缺陷,使用预制装配式桥梁已成为桥梁建设的发展趋势。装配式桥梁采用工厂化生产现场拼装技术,提高了机械化施工水平,加快了施工进度,有利于环境保护,具有明显的优越性。装配式桥梁的桥墩作为桥梁结构的主要承重构件,与承台的连接是装配式桥梁结构受力的薄弱部位,在地震中容易遭受破坏。常见的预制墩柱与承台的连接分为现浇式和承插式。这两种连接方式预制桥墩拼装定位难度大,现场钢筋焊接工作量大,混凝土浇筑工艺复杂,墩柱与承台结合部的抗剪性能差。本文结合济祁高速淮河特大桥引桥工程,基于圆形空心钢筋混凝土预制桥墩与承台的两种新型连接方式的现场原位加载试验,利用非线性有限元分析软件ABAQUS对两种连接方式的受力及变形性能进行了数值模拟,提出了合理的工艺流程确保墩底和承台的连接质量。主要研究内容包括:(1)通过现场原位加载试验,了解桥墩与承台结合部的破坏过程及破坏形态,获得了试件的荷载-位移曲线以及荷载-应力曲线等试验数据,对比分析了钢板剪力钉和梯形剪力环两种连接方式的受力性能和变形能力。试验表明,试件的最终破坏形态均为弯曲破坏,两种试件的破坏模式基本相同,均为墩底后浇杯口顶面上方连接区段,预制墩受拉侧混凝土开裂,发生弯曲破坏。采用梯形剪力环连接方式的连接性能更稳定。(2)选取合适的试件材料的应力-应变本构关系,利用有限元软件ABAQUS建立了试件的有限元分析模型,通过设置合理的边界条件及截面接触,进行适当的网格划分,模拟试件在水平和竖向加载作用下的受力过程,绘制结构能力曲线。并将模拟计算结果与试验结果进行对比分析,两者吻合较好,验证了预制装配式空心桥墩与承台结合部有限元模拟的合理性。(3)在试验研究和理论分析的基础上,对两种连接方式的施工方法进行对比分析及客观评价,提出了合理的施工工艺流程,形成了较为系统的施工工法,并成功的运用于实际工程中。在此基础上形成2项国家实用新型专利已获授权,获得1项省级施工工法。论文研究为进一步完善预制装配式桥梁的应用提供了理论依据和施工方法,对促进我国装配式混凝土桥梁在工程实践中的应用,推动建筑工业化的发展具有一定的意义。
[Abstract]:The construction of bridge piers in our country mostly adopts cast-in-place concrete construction technology. This traditional construction method has many wet work on the spot and long construction period, which has a great influence on the surrounding environment and does not accord with the requirements of building industrialization and green construction. In order to deal with the defects of cast-in-place concrete construction, the use of prefabricated bridges has become the development trend of bridge construction. The assembly bridge adopts the field assembling technology of factory production, which improves the mechanization construction level, speeds up the construction progress, is advantageous to the environmental protection, and has obvious superiority. The pier of prefabricated bridge is the main bearing member of the bridge structure, and the connection with the cap is the weak part of the prefabricated bridge structure, which is easy to be damaged in the earthquake. The common connection between prefabricated pier column and cap can be divided into cast-in-place type and socket type. It is difficult to assemble and locate the two kinds of prefabricated piers, the welding work of steel bar in the field is large, the pouring technology of concrete is complicated, and the shear resistance of the joint part of pier column and cap is poor. In this paper, the field in-situ loading test based on two new connecting modes of circular hollow reinforced concrete precast pier and cap is carried out on the basis of the approach bridge project of Jiqi High-speed Huaihe River Bridge. The nonlinear finite element analysis software ABAQUS is used to simulate the stress and deformation performance of the two connection modes, and a reasonable technological process is put forward to ensure the connection quality between the pier bottom and the cap. The main research contents include: (1) through in-situ loading test, the failure process and failure pattern of the joint of pier and cap are understood, and the load-displacement curve and load-stress curve of the specimen are obtained. The mechanical properties and deformation capacity of steel plate shear nail and trapezoidal shear ring are compared and analyzed. The test results show that the ultimate failure mode of the specimens is bending failure, and the failure modes of the two specimens are basically the same, both of which are connected section above the top surface of the post-pouring cup mouth at the bottom of the pier, and the precast pier is cracked by the tensile side concrete, which results in bending failure. The connection performance of trapezoidal shear ring is more stable. (2) the stress-strain constitutive relation of the appropriate specimen is selected, and the finite element analysis model of the specimen is established by using the finite element software ABAQUS. By setting reasonable boundary conditions and cross section contact, proper mesh division is carried out, the stress process of the specimen under horizontal and vertical loading is simulated, and the structural capacity curve is drawn. The results of simulation and test are compared and analyzed, which are in good agreement with each other, and verify the rationality of finite element simulation of the junction of prefabricated hollow bridge piers and caps, which is based on the experimental research and theoretical analysis. This paper makes a comparative analysis and objective evaluation of the two construction methods, and puts forward a reasonable construction process, which forms a more systematic construction method, and is successfully applied in practical engineering. On this basis, two national utility model patents have been authorized and one provincial construction method has been obtained. This paper provides the theoretical basis and construction method for the further improvement of the application of prefabricated concrete bridges. It is of certain significance to promote the application of prefabricated concrete bridges in engineering practice and to promote the development of building industrialization.
【学位授予单位】：合肥工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：U443.2

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