FRP加固混凝土梁抗弯性能有限元分析
发布时间：2018-07-22 21:12
【摘要】：混凝土材料由于其自身诸多的优点,多年来一直在土木工程中被广泛应用。混凝土是一种由骨料和砂浆构成的非线性材料,由于混凝土浇筑初期的硬化过程和水化作用,使得骨料和砂浆结合面处存在大量的初始裂缝。很多研究表明：混凝土的非线性就是由于这些裂缝的张开、闭合和发展造成的,混凝土损伤过程涉及许多重要的细观力学机制。目前国际上已经开始注意到从混凝土细观尺度出发研究混凝土宏观损伤与断裂过程的许多优点,尤其是当今计算机技术的发展,为从细观层次研究宏观层次的力学问题开辟了广阔的前景。本论文立足于对混凝土材料特性的认识,通过统计理论中的Weibull分布来表征混凝土材料力学参数的非均质性,分析了不同均质度对混凝土力学性能的影响；改进了Weibull分布表征的随机分布形式,引入空间相关尺度因子,对随机场内空间相关尺度因子对材料性能的影响进行了分析。此外,基于梁截面弯矩-曲率关系分析方法和共轭梁法,利用Fortran语言编制非线性有限元程序对FRP加固混凝土梁进行数值模拟分析,计算得到的荷载-挠度曲线可以与试验结果较好吻合；提出滞后应变计算方法,并且与现有方法进行对比,结果表明本文计算方法具有较高的计算精度；推导出FRP加固混凝土梁抗弯承载力计算公式,计算结果与试验结果和数值模拟结果均较为近似。
[Abstract]:Concrete material has been widely used in civil engineering for many years because of its many advantages. Concrete is a nonlinear material consisting of aggregate and mortar. Due to the hardening process and hydration of concrete at the early stage of concrete pouring, there are many initial cracks in the combination of aggregate and mortar. A lot of studies show that the concrete is mixed with concrete. The nonlinearity of the soil is due to the opening, closing and development of these cracks. The damage process of concrete involves many important meso mechanical mechanisms. At present, many advantages of concrete macroscopic damage and fracture process have been paid attention to from the meso scale of concrete, especially in today's computer technology. This paper has opened up a broad prospect for studying the mechanical problems at the macro level from the meso level. This paper is based on the understanding of the properties of concrete materials, characterizing the heterogeneity of the mechanical parameters of concrete materials through the Weibull distribution in the statistical theory, and analyzing the influence of the different homogenization on the mechanical properties of concrete; and the improvement of Weibull The spatial correlation scale factor is introduced to analyze the influence of spatial correlation scale factors on the properties of the material. In addition, based on the beam section bending moment curvature relationship analysis method and the conjugate beam method, the nonlinear finite element program is used in the Fortran language to carry out the numerical value of the FRP reinforced concrete beams. The simulated analysis shows that the calculated load deflection curve can be in good agreement with the test results, and the lagging strain calculation method is proposed and compared with the existing methods. The results show that the calculation method of this method has a higher calculation precision. The calculation formula of the bending bearing capacity of FRP reinforced concrete beams is derived, and the calculation results and the experimental results and numbers are also derived. The results of the value simulation are all similar.
【学位授予单位】：东北大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TU37
本文编号：2138590
[Abstract]:Concrete material has been widely used in civil engineering for many years because of its many advantages. Concrete is a nonlinear material consisting of aggregate and mortar. Due to the hardening process and hydration of concrete at the early stage of concrete pouring, there are many initial cracks in the combination of aggregate and mortar. A lot of studies show that the concrete is mixed with concrete. The nonlinearity of the soil is due to the opening, closing and development of these cracks. The damage process of concrete involves many important meso mechanical mechanisms. At present, many advantages of concrete macroscopic damage and fracture process have been paid attention to from the meso scale of concrete, especially in today's computer technology. This paper has opened up a broad prospect for studying the mechanical problems at the macro level from the meso level. This paper is based on the understanding of the properties of concrete materials, characterizing the heterogeneity of the mechanical parameters of concrete materials through the Weibull distribution in the statistical theory, and analyzing the influence of the different homogenization on the mechanical properties of concrete; and the improvement of Weibull The spatial correlation scale factor is introduced to analyze the influence of spatial correlation scale factors on the properties of the material. In addition, based on the beam section bending moment curvature relationship analysis method and the conjugate beam method, the nonlinear finite element program is used in the Fortran language to carry out the numerical value of the FRP reinforced concrete beams. The simulated analysis shows that the calculated load deflection curve can be in good agreement with the test results, and the lagging strain calculation method is proposed and compared with the existing methods. The results show that the calculation method of this method has a higher calculation precision. The calculation formula of the bending bearing capacity of FRP reinforced concrete beams is derived, and the calculation results and the experimental results and numbers are also derived. The results of the value simulation are all similar.
【学位授予单位】：东北大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TU37
【参考文献】
相关期刊论文 前1条
1 唐欣薇;周元德;张楚汉;;考虑空间相关尺度特征的细观力学模型及其应用[J];岩土力学;2012年07期
，本文编号：2138590
本文链接：https://www.wllwen.com/kejilunwen/sgjslw/2138590.html
