Experimental Study On Mechanical Properties And Durability Of High-strength Concrete

High-strength concrete is well adapted to the needs of modern engineering for its excellent characteristics, but with the increasingly wide application range, many problems are getting exposed, especially because of the improper materials and maintenance system, the actual structure the stress state is far below its design use, so that the structure can not be obtained using the function into full play, and shorten the life of the structure, resulting in a waste of potential safety problems and the economy. Hence the need for high strength concrete impact force performance and durability by raw materials, additives and construction methods in the process of curing depth research and analysis in order to be able to play more of the economic and security advantages of high strength concrete.In this paper, starting from the composition of high strength concrete, high strength concrete based on the composition of its various properties were described, and the factors affecting the performance of research carried out in-depth analysis; Based on the above analysis, for the mechanism of high-strength concrete durability were studied; order to explore the impact of raw materials and conservation methods on the mechanical properties of high strength concrete and durability, we design and implement the relevant experimental studies, the final test results were analyzed and summarized. Specific studies and results are as follows:(1) Systematic study of the material composition of high-strength concrete and its effect on the mechanical properties of high strength and durability of concrete and conducted in-depth analysis of its impact mechanism;(2) Design of high strength concrete mechanics performance and durability test scheme, the fly ash, silica fume and water reducing agent on the mechanical properties of high strength concrete and durability are analyzed. Little effect of fly ash on the early strength of high strength concrete, high strength concrete splitting tensile strength of the impact is relatively small, the influence of flexural strength is relatively large; different from fly ash, silica fume can improve the early strength of high strength concrete, high strength concrete with silica fume on the splitting tensile strength and flexural strength are affected relatively large; similar with silica fume, efficient water reducing agent can effectively improve the early strength of high strength concrete superplasticizer, but the splitting tensile strength and flexural strength of silica fume effect is slightly larger for high strength concrete;(3) launched a high-strength concrete materials mechanical properties and durability of the impact test, from the perspective of experiments to in-depth analysis of various factors on the performance of high-strength concrete affect the test results showed that early on fly ash concrete intensity of the impact is not obvious, but the latter can effectively improve the strength of concrete; silica fume not only can effectively improve the late strength of concrete, its early strength has also increased significantly. Although super plasticizer early and late can increase strength of concrete, but the rate of increase is not obvious effect of silica fume. Fly ash, silica fume and super plasticizer in high-strength concrete strength while improving its durability but also have a significant role in upgrading.High strength concrete standard curing at room temperature, water conservation and water curing three kinds of maintenance mode specimen relationship: hot water curing is better than room temperature water, and room temperature water is better than standard water, indicating that a higher curing temperature and humidity are conducive to improve the strength of high strength concrete.(4) High strength concrete has good resistance to water penetration, carbonation and chloride ion penetration test on it, the results show that the higher the strength of high strength concrete, the carbonation and chloride ion penetration ability is strong.