有损伤预应力混凝土T梁静载试验和有效预应力检测方法

发布时间：2018-01-14 12:19

本文关键词：有损伤预应力混凝土T梁静载试验和有效预应力检测方法　出处：《石家庄铁道大学》2014年硕士论文　论文类型：学位论文

【摘要】：预应力混凝土桥梁构件中的有效预应力是影响桥梁营运安全和使用寿命的关键因素，一旦预应力出现较大损失，就有可能导致突发的脆性断裂事故，造成灾难性的后果。近年来，关于桥梁损伤判定和维修加固技术的研究越来越受到工程界的重视，但由于预应力施加后就成为结构内力，很难直接测得，因此，对结构构件中有效预应力的判定仍存在较大困难，，而准确识别有效预应力这一工作又对营运部门维修加固策略的选择具有重要的工程实际意义。 2012年京通线某桥换梁，更换下来2片跨度23.8m预应力混凝土梁，为进行“既有线预应力混凝土T梁工作性能及剩余预应力识别方法研究”这一课题的研究工作提供了很好的机会。文中以其中一片梁为研究对象，分别进行了静载试验、消压荷载测试以及混凝土应力释放法等试验，对梁的有效预应力进行识别计算，论文主要进行了以下研究工作：（1）归纳总结国内外预应力混凝土构件中有效预应力检测方法，着重分析阐述了混凝土应力释放法的理论依据及其应用发展；（2）使用ANSYS软件建立了试验梁的混凝土应力释放法有限元计算模型，并得出槽间距为10cm、槽长为30cm、槽深为3cm就能实现混凝土应力释放的结论；（3）进行现场足尺寸梁试验，通过消压荷载测试结果得到构件中预应力损失量为26.48%，通过混凝土应力释放法试验得到构件中预应力损失为18.24%，按现行规范通过理论计算得到构件中预应力损失为28.86%。本论文研究成果可为运营部门对同批次梁的工作性能评估工作提供依据，为维修加固策略的选择提供参照。
[Abstract]:The effective prestress of prestressed concrete bridge components is a key factor affecting the operation of the bridge safety and durability of prestressed, once appear larger losses, it may lead to brittle fracture accident, resulting in disastrous consequences. In recent years, on the bridge damage determination and maintenance of reinforcement technology has attracted more and more attention in Engineering field. But because of the internal force of the structure becomes the prestress, it is difficult to directly measure, therefore, to determine the effective prestress in structural members still exist great difficulties, and accurately identify the effective prestress of the job but also has important practical significance in strengthening the strategy choice of operating maintenance department.
2012 Beijing line of a bridge for beam, replaced 2 span prestressed concrete 23.8m beam, provide a good opportunity for the research work of this topic of "research" of existing prestressed concrete T beam performance and residual prestress identification method. In the paper, in which a beam as the research object, respectively under static load test, load test and elimination of concrete stress releasing method tests, to identify the effective prestress beam calculation, this paper mainly conducted the following research work:
(1) summarize the detection methods of effective prestressing force in prestressed concrete components at home and abroad, especially analyze and explain the theoretical basis and application development of concrete stress relief method.
(2) using ANSYS software to establish the finite element calculation model of concrete stress releasing method for test beams, and get the conclusion that the stress of the concrete is released when the slot spacing is 10cm, the trough length is 30cm, and the groove depth is 3cm.
(3) test site full size beam, by reducing load test result of prestress loss component content is 26.48%, the concrete stress releasing method test of prestress loss component was 18.24%, according to the current codes obtained by theoretical calculation of prestressed loss component for 28.86%.
The research results in this paper provide the basis for the operation performance evaluation of the same batch beam, and provide reference for the selection of the maintenance and reinforcement strategy.

【学位授予单位】：石家庄铁道大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U446

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