Influence Of Cement Tvpes And Sand On The Properties Of High Performance Concrete And Cracking Risk Analysis

As the concrete is more and more widely used in engineering field, and the resulting early structure cracking problem is becoming more and more serious. Early age crack problem of concrete lead to the concrete deterioration of engineering structures and affect the durability of the structure. Especially, express highway and tunnel appear many this phenomena, which had affected economical quickly development greatly. Therefore, preparing concrete mixed with mineral admixtures with a good workability and crack resistance ability through tests and theoretical research on the early cracking problems of concrete can improve the durability of concrete engineering and guarantee the quality of concrete engineering and safety, which is of great significance. Based on all of these, the main research work is as follows:1. In practical engineering, instability sources of raw material of concrete have serious impact on the quality of concrete. From the source of the life cycle of concrete, the impact of cement types, sand fineness modulus on concrete work performance and basic mechanical properties has been studied. Basic mechanical properties of concrete mixed with mineral admixture have also been tested for up to360d.The relationship between the basic mechanical properties of concrete with the age and the law of their relationships was studied, which considered the effect of concrete compressive strength with age in the study of compressive strength and considered the relationship between the tensile strength and compressive strength of the concrete.2. According to tests, the influence of cement types, sand fineness modulus of concrete on impermeability, free shrinkage performance, cracking resistance was studied, a comprehensive evaluation of the different mix of concrete’influence on the durability and shrinkage cracking resistance performance of concrete has been done.3. By comparing performance of concrete mixed with mineral admixtures and the basic mixed concrete, it was found that the right amount of mineral admixtures mixed with concrete can improve the mechanical, impermeability and shrinkage cracking resistance properties of concrete at later age.4. From the factors affecting the concrete cracking, a comprehensive analysis of the influence of mechanical properties of concrete, temperature deformation, shrinkage and other factors on the concrete cracking, cracking risk prediction model of concrete under heterogeneous load was established, by using large finite element analysis software ANSYS, the variation of temperature, humidity and stress of restraint slab of concrete has been analyzed...