On design of mixing ratio of concrete C70

The strength of concrete is increasing constantly all over the world.How to make full use of materials' performance and create the concrete with higher strength and durability is the inevitable trends of development of concrete.The paper mainly aims at the experiments made on the designed high performance and high strength concrete;and makes brief introductions about the selection of raw materials and the trial mixture of concrete.The experiments validate that the results of the concrete accord with the requirements of JGJ/T55-2000;so that the concrete is suitable for use in the construction sites.