Research Of Ultra-High Strength And High Wear-Resistant Concrete Material

With the development of concrete research, the high performance cement-based composite material has been paid high attention to in worldwide. High performance and high wear-resistant concrete has been prepared by using wearable aggregates such as sintered bauxite, alumina ceramic and so on in some company abroad and has been used in the practical projects. But the wear-resistant performance was lessly involved in the research of high performance concrete at domestic, however, concrete with high wear-resistant performance is needed in many practical projects, such as heavy plant, runway of the airport, lining of large-scale pipe and so on.In the paper, the high pozzolanic activity and filling effect of silica fume was fully used, steel fiber was incorporated to improve the ductility of concrete. Under the instruction of the theory of high performance concrete, the preparing method of ultra-high strength cement-based material was used. Through test, studies were made among the effects of properties and mix amount of materials such as superplasticizer, silica fume, steel fiber and sintered bauxite on the strength, fluidity and wearability of concrete.The test studies indicated that, the variety and mix amount of superplasticizer, silica fume, steel fiber, aggregates and water-binder ratio have effects of different degree on the performance of concrete. Considering the influence of the factors on fluidity of freshly mixed concrete, compressive strength and abrasion value, it is considered that when water-binder ratio is about 0.20, silica fume-cement ratio is 0.25, mix amount of superplasticizer is 2% and aggregate mix amount to cement mix amount is about 1.1, the comprehensive performance of concrete is better.With the adoption of silica sand, sintered bauxite, brown corundum and black silicon carbide respectively as the concrete aggregate, cubic compressive strength and abrasion value of concrete under three curing methods were tested by the method of The Orthognal Test Design. Variance analysis of 28d compressive strength and abrasion value of concrete prepared of four kinds of aggregates were done, and the influence level of experimental factors to indexes were further analyzed. Concrete prepared of four kinds of aggregates were comprehensively compared in four aspects including fluidity of freshly mixed concrete, phenomenon of abrasion test of concrete specimens, compressive strength and abrasion value of concrete. Then considering the price of materials, the conclusion was got that, the comprehensive performance of concrete prepared of sintered bauxite is the best of the four aggregates, concrete of ultra-high strength and high wear-resistant performance can be prepared of sintered bauxite.By variance analysis of the orthogonal test results of concrete prepared of sintered bauxite, the influence level of experimental factors to compressive strength and wear-resistant performance of concrete under three curing methods were obtained. The development rules of compressive strength and abrasion value of concrete prepared of sintered bauxite under three curing methods were studyed. By comparing compressive strength and abrasion value of concrete prepared of sintered bauxite of the nine mixture ratios, the result was got that the fourth mixture ratio was the best one,and the concrete prepared of sintered bauxite according to the fourth mixture ratio was of ultra-high strength and high wear-resistant performance that research the target of the study, and its 28d compressive strength was up to 132.4MPa, abrasion value was 0.0912g/cm2.