基于非概率理论的碳纤维布加固桥梁可靠性研究

发布时间：2018-01-23 11:42

本文关键词： 非概率可靠性碳纤维布加固区间模型改进一维优化算法　出处：《武汉工程大学》2015年硕士论文　论文类型：学位论文

【摘要】：粘贴碳纤维布加固桥梁具有施工方便、耐腐蚀等优点,在桥梁维修加固工程中得到了推广应用。由于传统的概率模型分析需要足够的数据信息,且对参数取值范围的变化很敏感。而非概率模型对数据样本的要求较低,只需参数变量的上下限。因此在桥梁加固工程中,非概率可靠性分析方法具有很强的实用性。本文首次将非概率可靠性理论应用到碳纤维布加固桥梁的分析中,说明碳纤维布加固效果的可靠性和合理性。具体研究内容如下:(1)在阅读相关规范与文献的基础上,详细的介绍了非概率可靠性的区间概念、可靠性模型以及非概率可靠性指标的计算方法。(2)根据非概率可靠性理论提出了加固前桥梁的非概率可靠性分析的研究方法。通过一个具体的工程实例,对加固前的桥梁进行敏感性分析,找出影响结构功能函数大的区间变量。利用区间模型的一维优化算法求解非概率可靠性指标,为加固前的桥梁提供了研究依据。(3)对常见的几类桥梁加固方法进行归纳总结,根据工程经验分析,对实例桥梁选择合适的加固方法。本文选择碳纤维布加固方法,并对加固后的桥梁进行非概率可靠性分析,分别通过改进一维优化算法和失效点寻优法求解非概率可靠性指标。改进一维优化法主要针对极限状态方程已知的情况,但实际工程中很多桥梁的极限状态方程不易求出,需要求助有限元建模分析方法。应用已有的失效点寻优法进行建模数值求解,同时和改进一维优化算法进行比较,为那些粘贴碳纤维布加固得不到功能函数的桥梁提供思路。最后通过改变碳纤维布的宽度以及层数,研究加固后非概率可靠性指标的变化,为碳纤维布加固桥梁提供依据。
[Abstract]:The bridge strengthened with CFRP has the advantages of easy construction, corrosion resistance and so on. It has been widely used in bridge maintenance and reinforcement engineering. Due to the traditional probability model analysis needs enough data information. And it is sensitive to the change of the range of parameter values, but the non-probabilistic model requires less data samples, only the upper and lower limits of parameter variables. Therefore, in the bridge reinforcement engineering. The non-probabilistic reliability analysis method is very practical. In this paper, the non-probabilistic reliability theory is applied to the analysis of CFRP strengthened bridges for the first time. Explain the reliability and rationality of CFRP reinforcement effect. The specific research contents are as follows: 1) on the basis of reading the relevant codes and literature, the non-probabilistic reliability interval concept is introduced in detail. Based on the theory of non-probabilistic reliability, the research method of non-probabilistic reliability analysis of bridges before reinforcement is put forward. A concrete engineering example is given. The sensitivity analysis of the bridge before reinforcement is carried out to find out the interval variables that affect the large function of the structure. The one-dimensional optimization algorithm of the interval model is used to solve the non-probabilistic reliability index. This paper provides the research basis for the bridge before reinforcement. (3) summarizes the common methods of bridge reinforcement and analyzes them according to the engineering experience. In this paper, the method of CFRP reinforcement is chosen, and the non-probabilistic reliability analysis of the strengthened bridge is carried out. The improved one-dimensional optimization algorithm and the failure point optimization method are used to solve the non-probabilistic reliability index respectively. The improved one-dimensional optimization method is mainly aimed at the case where the limit state equation is known. However, the limit state equation of many bridges in practical engineering is difficult to be solved, so it is necessary to use finite element modeling and analysis method. The existing failure point optimization method is used to solve the numerical model. At the same time, compared with the improved one-dimensional optimization algorithm, it provides ideas for those bridges that can not be strengthened with CFRP sheets. Finally, by changing the width and the number of layers of CFRP sheets. The change of non-probabilistic reliability index after reinforcement is studied to provide basis for strengthening bridge with carbon fiber sheet.
【学位授予单位】：武汉工程大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U445.72

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