Study On High Performance Concrete For CRTS Ⅱ Rail Slab Of Passenger Special Line

High performance concrete, as the new material of 21st century, has been widely used in large projects, such as high speed railway project, for its high strength, high workability, and high durability. The study on high performance concrete has been a hot point in concrete study, and how to rationaly get the mix proportion, how to get the characteristic of high strength, high workability, and high durability economically and effectively, has been a burning question.In this paper, based on experiment, high performance concrete for CRTSⅡrail slab of passenger special line is studied. According to the experiment data, the design of mix proportion, the effect factors of compress strength and durability of C55 high performance concrete for CRTSⅡrail slab is studied, and the study result is concluded.1. Orthogonal test is used to choose the better mix proportion, in which water to binder ratio, sand ratio and mineral ratio are comprehensively considered. According to the specific experiment data, comparing every effect factor of concrete strength with each other, the best mix proportion is found by several mathematical methed, such as figure analysis and range analysis. The best mix proportion is 0.29 for water to binder ratio,37% for sand ratio and 10% for mineral ratio.2. Using orthogonal test, the effect of water to binder ratio, sand ratio and mineral ratio to concrete compress strength in defferent age is studied by figure analysis and variance analysis. The study results show that each factor has the defferent effect to concrete strength in defferent age, the effect of mineral ratio is prominent in early age which will become unconspicuous in late age, the effects of water to binder ratio and sand ratio are unconspicuous, and after 28 days only the effect of water to binder ratio is prominent.3. The method of regression analysis is used to find the relation between concrete compress strength and concrete age. The study results show that there is high linear relation between them which is the formula P=b·ln(T)＋a. The results also show that the mineral admixture will raise the developing speed of concrete strength. Also using the method of regression analysis, the strength formulas of 28d strength and 16h strength are deduced, according to Belomey Formula.4. The durabilities of high performance concrete, such as permeability resistance, crack resistance, frost resistance, sulfate resistance, are studied through the experiments of high performance concrete durability. The effect factors are concluded and the method how to raise concrete durability is put forward.