高墩大跨连续刚构桥挠度与应力主动控制研究

发布时间：2018-05-16 09:25

本文选题：非对称高墩大跨连续刚构桥 + 主动控制　；参考：《山东大学》2015年硕士论文

【摘要】：由于经济建设的需要,高墩大跨连续刚构桥的应用也越来越广泛,其安全问题也越来越需要重视,与一般的连续刚构桥相比,非对称高墩大跨连续刚构桥在合拢期间结构受力更为复杂且线形不易控制,因此有必要对其合拢期间结构的挠度与应力实施主动控制,以确保成桥后结构线形可以满足设计要求。本文以凯峡河特大桥主桥为依托,对非对称高墩大跨刚构桥合拢期间的主动控制技术进行了相关研究。首先,主要总结与介绍了温度作用以及混凝土收缩徐变作用对高墩大跨连续刚构桥在合拢成桥期间与后期长期运营过程中的结构内力与变形的影响。其次,对合拢期问顶推主动控制技术进行了研究。详细研究了所需顶推力的计算方法,利用有限元模拟分析得出了当结构实际合拢温度不同于设计合拢温度时,应该如何合理选取顶推位移与顶推力。另外研究了不同合拢顺序下对结构变形和内力的影响,并通过比较确定按照边跨、次中跨、主中跨的合拢顺序为最优合拢顺序。最后,对合拢段预应力钢束不同张拉顺序对结构的影响进行了分析研究,发现按照先长束后短束的张拉顺序较为合理,最后提出了减少预应力损失的相关建议,建议在跨中下挠较大时及时设置备用束。
[Abstract]:Because of the need of economic construction, the application of high pier and long span continuous rigid frame bridge is becoming more and more extensive, and its safety problems need more and more attention. Compared with the general continuous rigid frame bridge, the structural stress is more complex and the line shape is not easy to control during the closure of the continuous rigid frame bridge with asymmetric high piers, so it is necessary to the torsion of the structure during the closure. On the basis of the main bridge of the kayaxi River Bridge, the research on the active control technology of the unsymmetrical high pier and Large Span Rigid Frame Bridge is studied in this paper. First, the effect of temperature and the action of shrinkage and creep of concrete are introduced. The influence of pier Large Span Continuous Rigid Frame Bridge on structural internal force and deformation during the period of closure and later period of long term operation. Secondly, the active control technology of closing time is studied. The calculation method of the required thrust is studied in detail. It is concluded that the closing temperature of the structure is different from the design combined with the finite element simulation analysis. At the temperature, how to select the push displacement and the top thrust should be reasonably selected. In addition, the effect of different closure sequence on the structural deformation and internal force is studied. By comparison, the optimal closure order is determined according to the side span, the secondary span and the closure order of the main and middle span. Finally, the influence of the different tensile order of the pre stress steel bundles on the structure is carried out. It is found that the tensioning order of the short beam is more reasonable in accordance with the first long beam. Finally, some suggestions are put forward to reduce the loss of prestress. It is suggested that the spare beam should be set in time when the middle and lower deflection is larger.

【学位授予单位】：山东大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U448.23

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