钢纤维混凝土等效弹性模量的均匀化理论及计算

发布时间：2018-10-16 11:16

【摘要】：钢纤维混凝土是一种性能优良、运用较广的新型复合材料，钢纤维混凝土抗拉、抗弯以及抗剪强度比普通混凝土强度高，前人对钢纤维混凝土的力学性能进行了广泛的研究。弹性模量是钢纤维混凝土的一项重要的力学性能，前人一般采用实验法或者理论计算法对钢纤维混凝土弹性模量进行研究，本文采用均匀化理论结合有限元分析研究二维乱向钢纤维混凝土等效弹性模量。主要研究内容及结论如下：（1）对钢纤维的应用与发展、钢纤维在混凝土内大体的分布情况、钢纤维的基本特性以及钢纤维混凝土的发展和应用现状、基本理论研究做了总结回顾。（2）对均匀化理论以及将钢纤维混凝土进行均匀化处理做了详细的介绍。（3）建立3D单胞模型，将几何模型导入HyperMesh，划分网格、分配材料属性、导出模型并导入ANSYS，编写均匀化程序完成有限元模型后处理。（4）研究钢纤维混凝土内钢纤维的不同含量、不同长径比、不同分布以及基体不同强度对等效弹性模量的影响，并将得到的数值与文献值进行对比。研究结果表明：钢纤维含量的增加能提高材料的等效弹性模量、长径比的改变对材料的等效弹性模量的影响不是很大、钢纤维的分布能改变材料的弹性模量、基体强度的改变能改变材料的等效弹性模量、当钢纤维体积率低于1.2%时，等效弹性模量与现有研究成果基本吻合，可知利用均匀化理论研究二维乱向分布的钢纤维混凝土弹性模量具有可行性。当钢纤维体积率超过1.2%时，，不适应于运用均匀化理论计算其等效弹性模量。（5）现今广泛运用的层布式钢纤维混凝土路面是由二维乱向钢纤维混凝土组成，当钢纤维含量低于1.2%时，对于采用钢纤维混凝土的刚性路面可用均匀化方法，将路面各层均匀化成为一个叠层板体系用以研究路面的受力性能。
[Abstract]:Steel fiber reinforced concrete (SFRC) is a new type of composite material with excellent properties and wide application. The tensile, flexural and shear strength of SFRC is higher than that of ordinary concrete. The mechanical properties of SFRC have been studied extensively. Elastic modulus is an important mechanical property of steel fiber reinforced concrete (SFRC). In this paper, the equivalent elastic modulus of two-dimensional steel-fiber reinforced concrete (SFRC) is studied by using homogenization theory and finite element analysis. The main contents and conclusions are as follows: (1) the application and development of steel fiber, the general distribution of steel fiber in concrete, the basic characteristics of steel fiber and the development and application of steel fiber concrete. The basic theoretical research is summarized and reviewed. (2) the homogenization theory and the homogenization of steel fiber reinforced concrete (SFRC) are introduced in detail. (3) the 3D unit cell model is established and the geometric model is introduced into HyperMesh, to mesh. Distribution of material properties, derivation of model and introduction of ANSYS, homogenization program to complete finite element model post-processing. (4) the different content and aspect ratio of steel fiber in steel fiber reinforced concrete are studied. The effects of different distributions and different strength of the matrix on the equivalent elastic modulus are compared with those obtained in the literature. The results show that the increase of steel fiber content can increase the equivalent elastic modulus of the material, and the change of aspect ratio has little effect on the equivalent elastic modulus of the material, and the distribution of steel fiber can change the elastic modulus of the material. The change of matrix strength can change the equivalent elastic modulus of the material. When the volume ratio of steel fiber is lower than 1.2%, the equivalent elastic modulus is basically consistent with the existing research results. It is shown that it is feasible to study the elastic modulus of steel fiber reinforced concrete (SFRC) with the theory of homogenization. When the volume ratio of steel fiber exceeds 1.2, it is not suitable to use homogenization theory to calculate its equivalent elastic modulus. (5) the widely used layered steel fiber reinforced concrete pavement is composed of two-dimensional disorderly steel-fiber concrete. When the steel fiber content is lower than 1.2, the uniform method can be used for the rigid pavement with steel fiber reinforced concrete, and each layer of the pavement can be homogenized into a laminated slab system to study the mechanical properties of the pavement.
【学位授予单位】：湘潭大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TU528.572

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