预应力混凝土箱形梁局部应力分析

发布时间：2018-01-21 09:55

本文关键词： 预应力混凝土箱形梁主梁根部锚固区局部应力　出处：《长安大学》2014年硕士论文　论文类型：学位论文

【摘要】：目前，许多桥梁均采用预应力混凝土箱形梁建造。然而，在实际使用中，预应力混凝土箱形梁桥的裂缝开展是比较普遍的，特别是翼板与腹板交界处和锚固区，已经严重影响箱形梁桥的安全性和耐久性。针对这一比较严重的问题，本文从局部应力的角度出发，，通过有限元分析，进行了如下研究：首先介绍了箱形梁的优缺点，箱形梁的出现和发展；阐述了箱形梁因为局部应力引起的病害以及各局部应力的研究现状。然后分析了箱形梁的受力特点，介绍了箱梁局部应力的计算方法；介绍了混凝土局部承压的受力状态以及规范中关于局部承压区的验算规定。为了分析箱梁主梁根部截面局部应力，运用有限元分析软件Midas FEA，建立某三跨预应力混凝土连续梁桥的0、1号块空间实体有限元模型，分别分析了此桥在成桥运营状态下和施工最大悬臂状态主梁根部截面的局部应力大小和分布规律。并与用有限元软件Midas Civil所建立的杆系有限元模型计算结果进行了对比分析。最后对于锚固区局部应力的分布规律，针对预应力混凝土箱形梁桥中典型的锚固区位置，根据我国JTG D62-2004规范对局部承压区的验算规定，分别对腹板锚固区、齿板锚固区、端部群锚区进行了实体有限元分析，搞清了这些锚固区应力的大小以及分布规律，并对其原因进行了阐述。
[Abstract]:At present, many bridges are constructed with prestressed concrete box beam. However, in practical use, the crack development of prestressed concrete box girder bridge is quite common, especially at the junction of flange and web plate and anchoring area. The safety and durability of box girder bridge have been seriously affected. In view of this serious problem, this paper, from the point of view of local stress, through finite element analysis, has carried out the following research: Firstly, the advantages and disadvantages of box beam, the appearance and development of box beam are introduced, and the disease caused by local stress of box beam and the research status of each local stress are expounded. Then, the stress characteristics of box beam are analyzed, the calculation method of local stress of box girder is introduced, the stress state of concrete local bearing pressure and the checking calculation rules of local bearing zone in code are introduced. In order to analyze the local stress of the root section of the box girder, the finite element model of a three-span prestressed concrete continuous beam bridge is established by using the finite element analysis software Midas fea. The local stress size and distribution of the root section of the main beam under the operation condition of the bridge and the maximum cantilever state in construction are analyzed respectively. The results are compared with that of the finite element software Midas. The calculation results of the finite element model of the bar system established by Civil are compared and analyzed. Finally, for the distribution law of local stress in anchoring area, according to the JTG D62-2004 code of our country, according to the typical Anchorage zone location of prestressed concrete box girder bridge, the local pressure zone is checked and calculated. The finite element analysis of the web Anchorage zone, the tooth plate Anchorage area and the end group Anchorage area is carried out, and the magnitude and distribution of the stress in these Anchorage zones are clarified, and the reasons are expounded.
【学位授予单位】：长安大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U441.5

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