拱桥吊杆断裂响应分析及对策研究

发布时间：2018-12-09 11:28

【摘要】：吊杆作为中、下承式拱桥的关键构件,其重要性显而易见,而由于各种不确定因素的存在导致吊杆很可能会提前断裂,但现行的吊杆设计理论对吊杆骤断时拱桥的安全性考虑不足,且现有的理论与技术手段无法准确的判断吊杆何时断裂,因此吊杆突然断裂导致桥梁损毁的事故时有发生。为此,针对单吊杆系统拱桥,本文基于已有的研究进行拱桥吊杆断裂时的动力响应分析,并提出预防拱桥吊杆突然断裂的对策方法,对吊杆破损安全设计进行分析研究,旨在实现拱桥不会因吊杆突然断裂而坍塌,且能保证拱桥正常运营并给桥梁提供足够的修复时间。本文结合一中承式钢管混凝土拱桥,研究吊杆断裂对拱桥的影响,探讨分析单吊杆系统的破损安全设计方法。主要研究内容为:(1)总结引起吊杆断裂的原因及相关对策,分析了拱桥吊杆破损安全的研究现状,明确了进行吊杆破损安全设计的目的及意义。(2)综述了破损安全理论和破损安全结构的实现途径,基于多路传力的思想提出了两类针对单吊杆系统的吊杆破损安全设计方法,并将其应用到现有拱桥上进行研究。(3)运用半动力模拟方法模拟吊杆断裂时拱桥的响应,分析短吊杆与长吊杆断裂对拱桥的冲击作用,研究普通单吊杆系统拱桥吊杆断裂时的安全性,得出吊杆断裂时拱桥受力不利的地方,结果表明吊杆断裂可能会引起拱桥纵横梁连接失效导致桥梁损毁。(4)对单吊杆系统进行改造,将改造后的破损安全系统应用到茅草街大桥上,建模分析具有破损安全吊杆系统的拱桥的安全性能,分析结果表明改造后的破损安全吊杆系统能有效地提高拱桥的安全性能,证明了吊杆破损安全设计原理的合理性。(5)探讨了单吊杆系统破损安全的合理设计方法,所得的结论为设计人员进行单吊杆系统拱桥的吊杆破损安全设计提供了一定的参考价值。
[Abstract]:As the key component of the through arch bridge, the importance of the suspension rod is obvious, and because of the existence of various uncertain factors, it is likely to break ahead of time. However, the current design theory of suspenders has insufficient consideration for the safety of arch bridges when the suspenders break suddenly, and the existing theories and technical means cannot accurately judge when the suspenders break, so the accidents of the sudden rupture of the suspenders lead to the damage of the bridges from time to time. For this reason, based on the existing research, this paper analyzes the dynamic response of arch bridge suspenders when they break, and puts forward the countermeasures to prevent the sudden rupture of arch bridge suspenders, and analyzes and studies the safety design of suspenders' breakage. The purpose of this paper is to ensure that the arch bridge will not collapse because of the sudden rupture of the suspenders, and that the arch bridge can be operated normally and provide enough repair time for the bridge. In this paper, the influence of the break of suspenders on the arch bridge is studied, and the design method of the damage safety of single suspension system is discussed in combination with a middle through concrete filled steel tube arch bridge. The main research contents are as follows: (1) summarize the causes of the rupture of the suspenders and the relevant countermeasures, and analyze the current research situation of the safety and damage of the suspenders of the arch bridge. The purpose and significance of the design of the damaged safety of the suspension rod are clarified. (2) the theory of damage safety and the way to realize the damaged safety structure are summarized. Based on the idea of multi-channel force transfer, two kinds of safety design methods for single suspender system are proposed and applied to the existing arch bridge. (3) the response of arch bridge when the suspension is broken is simulated by semi-dynamic simulation method. This paper analyzes the impact of short and long suspenders on the arch bridge, studies the security of the common single suspension system when the arch bridge is broken, and draws the conclusion that the arch bridge is unfavorable to the force when the suspender is broken. The results show that the fracture of suspenders may lead to the failure of longitudinal and transverse beam connections of arch bridges and lead to bridge damage. (4) the single suspension system is reformed and the damaged safety system is applied to the Maocaojie Bridge. The safety performance of the arch bridge with damaged safety suspension system is analyzed. The analysis results show that the improved damaged safety suspension system can effectively improve the safety performance of the arch bridge. This paper proves the rationality of the design principle of the damage safety of the suspension rod. (5) the reasonable design method of the breakage safety of the single boom system is discussed. The conclusion provides a certain reference value for designers to design the damaged safety of single suspension system arch bridge.
【学位授予单位】：长安大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：U448.22

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