FRP抗弯加固钢筋混凝土梁的可靠度研究

发布时间：2018-01-19 23:14

本文关键词： FRP 混凝土可靠度加固梁　出处：《湖北工业大学》2017年硕士论文　论文类型：学位论文

【摘要】：纤维增强复合材料(FRP)是一种具有很高使用价值的新型材料,种类繁多,价格经济,与其他材料相比,它具有抗拉性好,质量较轻,耐腐蚀,使用方便等显著优点,因此在土木工程中得到了广泛的运用,由于我国建筑业面临着大量建筑需要修复与加固的问题,使用FRP对建筑进行加固的技术也越来越完善和成熟了,对于使用FRP加固的受弯破坏与承受力分析,国内外学者都进行过相关研究,并且提出了许多具有实际应用价值的模型,国家在这方面也较为重视,颁布了相关的设计规范。本文对FRP抗弯加固混凝土钢筋梁的四种具有代表性的破坏模式进行了分析,主要通过蒙特卡洛模拟的方法进行了相关的可靠度分析,除此之外,还对中美设计规范的差异进行了比较,本文工作及主要创新之处在于:(1)从国内外相关文献中收集关于FRP抗弯加固钢筋混凝土梁的有关试验数据,并且以此为基础建立一个庞大的数据库,并且,在此基础上,使用统计软件SPSS进行各个因素的方差分析,最终研究得出各个基本变量对于FRP共享比例。最终得出结论:混凝土轴心抗压强度,钢筋纵向配筋率,FRP截面配布率对FRP贡献比例有显著影响。(2)收集和整理现有文献对于FRP抗弯加固梁可靠度计算所涉及的各随机变量的统计特征的取值。另外,考虑到混凝土和FRP两种材料的强度对承载力较敏感,对600个混凝土试块进行立方体抗压以及50个FRP试件进行单轴拉伸试验,旨在得到这两种材料的力学性能的统计特征。分析试验结果结合现有文献,本文对于混凝土轴心抗压强度的均值与名义值之比取1.25,变异系数取0.15;FRP极限抗拉强度分别取1.15和0.1;FRP的弹性模量分别取1.0和0.04。(3)用中美规范的模型建立极限承载力的状态方程,然后通过计算,得出中国与美国的设计规范在可靠度方面的差异,还有变量对可靠度的影响情况。(4)根据Monte Carlo-JC法和Monte Carlo法分别编制了基于Matalb的计算程序,计算了海洋环境下混凝土梁加固前后的时变可靠度。同时通过对比两种可靠度计算方法,证明Monte Carlo-JC法是一种高效率的可靠度计算。
[Abstract]:Fiber reinforced composite (FRP) is a new material with high use value. It has many kinds of materials and is economical in price. Compared with other materials, FRP has good tensile resistance, light quality and corrosion resistance. Because of its obvious advantages, such as ease of use, it has been widely used in civil engineering, because the construction industry in our country is faced with a large number of problems of repair and reinforcement. The technology of using FRP to reinforce the building has become more and more perfect and mature. The domestic and foreign scholars have carried on the related research to the bending failure and the endurance analysis of using the FRP reinforcement. And put forward a lot of practical application value of the model, in this respect, the country also pay more attention to. In this paper, four representative failure modes of reinforced concrete beams strengthened with FRP bending are analyzed. In addition to the reliability analysis by Monte Carlo simulation, the differences between Chinese and American design specifications are compared. The main innovation of this paper lies in the collection of relevant experimental data on reinforced concrete beams strengthened with FRP flexural strength from domestic and foreign literature, and the establishment of a large database based on this data. And on this basis, using the statistical software SPSS to carry out the analysis of variance of each factor, the final study of the basic variables for the FRP share ratio. Finally, the conclusion: concrete axial compressive strength. Longitudinal reinforcement ratio. The distribution ratio of FRP section has a significant effect on the contribution ratio of FRP. (2) collecting and arranging the statistical characteristics of each random variable involved in the reliability calculation of FRP flexural strengthening beam. In addition. Considering that the strength of concrete and FRP is sensitive to the bearing capacity, 600 concrete specimens are tested under cube compression and 50 FRP specimens are subjected to uniaxial tensile test. The purpose of this paper is to obtain the statistical characteristics of the mechanical properties of the two kinds of materials. The experimental results are combined with the existing literature, and the ratio of the mean to nominal value of the axial compressive strength of concrete is 1.25 in this paper. The coefficient of variation was 0.15; The ultimate tensile strength of FRP is 1.15 and 0.1 respectively. The elastic modulus of FRP is taken as 1.0 and 0.04. 3 respectively) the state equation of ultimate bearing capacity is established by using the model of Chinese and American codes, and then calculated. The differences in reliability between Chinese and American design codes are obtained. And the influence of variables on reliability. 4) according to the Monte Carlo-JC method and Monte Carlo method, the calculation programs based on Matalb are developed respectively. The time-varying reliability of concrete beams before and after reinforcement in marine environment is calculated, and the Monte Carlo-JC method is proved to be a high efficiency reliability calculation by comparing two reliability calculation methods.
【学位授予单位】：湖北工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU375.1

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