基于可靠度最优分配的自锚式简支桁架悬索桥优化设计研究

发布时间：2018-01-12 05:18

本文关键词：基于可靠度最优分配的自锚式简支桁架悬索桥优化设计研究　出处：《河北工业大学》2015年硕士论文　论文类型：学位论文

【摘要】：获得经济且安全可靠的桥梁结构是桥梁设计师们所追求的目标,显然优化设计是获得这一目标的有效手段,但当前的确定性优化设计方法由于无法考虑实际工程中客观存在的不确定性而无法在工程中推广实施,而基于可靠度的优化设计方法恰恰可以弥补这方面的不足。但当前该方法的研究主要限于构件设计阶段,缺乏结构体系方面的研究工作。本文以自锚式简支桁架悬索桥为研究对象,尝试采用基于可靠度最优分配的优化设计理论,对整个结构体系及其组成构件进行了静力和动力可靠度优化设计,获得了更为经济合理的桥梁结构,同时为其它桥梁结构体系采用基于可靠度的优化设计方法提供了重要参考。本文主要研究工作如下:1.基于MATLAB平台开发编制了JC法的计算程序,大大提高了可靠性指标的求解效率。2.建立了基于可靠度最优分配的数学模型,并把模型应用到桁架结构中,对静定桁架和超静定桁架分别进行了优化设计,验证了基于可靠度最优分配的优化设计理论的适用性和有效性。3.采用ANSYS软件建立了自锚式简支桁架悬索桥的有限元分析模型,并应用修正?约界法对整个桥梁结构的失效路径进行了搜索,获得了桥梁结构体系的系统可靠度。4.对自锚式简支桁架悬索桥进行了基于可靠度最优分配的静力可靠度优化设计,优化了各组成构件的可靠度和截面尺寸,获得了更为经济合理的设计方案,达到了优化设计的目的,同时证明了基于可靠度最优分配的优化设计理论对大型桥梁结构优化设计的可行性。5.对自锚式简支桁架悬索桥进行了基于可靠度最优分配的动力可靠度优化设计,建立了结构体系的动力可靠度优化设计模型,采用反应谱方法对整个结构体系组成构件的可靠度及其设计变量进行了优化分配,初步显示了基于可靠度最优分配的优化设计理论在桥梁结构抗震设计中的潜力。
[Abstract]:It is the goal of bridge designers to obtain economical and safe bridge structure. It is obvious that optimal design is an effective means to achieve this goal. However, the current deterministic optimization design method can not be popularized and implemented in engineering because it can not take into account the uncertainty existing in the actual project. The reliability based optimization design method can make up for this deficiency, but the current research of this method is mainly limited to the component design stage. This paper takes self-anchored simply supported truss suspension bridge as the research object and tries to adopt the optimal design theory based on optimal reliability allocation. The static and dynamic reliability optimization design of the whole structure system and its components is carried out, and a more economical and reasonable bridge structure is obtained. At the same time, it provides an important reference for other bridge structure systems to adopt the reliability based optimization design method. The main research work of this paper is as follows: 1. Based on the MATLAB platform, the JC calculation program is developed. A mathematical model based on optimal reliability allocation is established, and the model is applied to truss structure. The statically indeterminate truss and statically indeterminate truss are optimized respectively. The applicability and validity of the optimal design theory based on optimal reliability allocation are verified. 3. The finite element analysis model of self-anchored simply supported truss suspension bridge is established by using ANSYS software and modified? The reduced-boundary method is used to search the failure path of the whole bridge structure. The system reliability of the bridge system is obtained. 4. The static reliability optimization design of self-anchored simply supported truss suspension bridge is carried out based on the optimal distribution of reliability, and the reliability and section size of each component are optimized. A more economical and reasonable design scheme has been obtained, and the purpose of optimal design has been achieved. At the same time, the feasibility of optimal design theory based on optimal reliability allocation for large bridge structures is proved. 5. Dynamic reliability optimization of self-anchored simply supported truss suspension bridges based on optimal reliability allocation is carried out. Design. The dynamic reliability optimization design model of the structural system is established, and the reliability and design variables of the whole structural system are optimized by using the response spectrum method. The potential of optimal design theory based on optimal reliability allocation in seismic design of bridge structures is shown.
【学位授予单位】：河北工业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U448.25

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