S75 Grade Granulated Blast Furnace Slag Powder Is Used To Improve Concrete Erosion Resistance Performance Study

The study of S75 granulated blast funace slag powder,in order to better save energy and reduce emissions,to develop green building materials,to solve the problem of corrosion resis tance of concrete buildings in Xinjiang environmental crosive medium area,and to reduce the cost of building materials,The research results have important practical significance and refe rence value.Based on grade S75 slag powder as raw material,this paper studies the influence of different slag content on the corrosion resistance of concrete under different water-binder ratio by changing the water-binder ratio and the content of slag powder.The main research results are as follows:(1)When the water-binder ratio of ordinary cement is 0.4,0.35 and 0.3,high-efficiency water-reducing agent with different content is selected and different amount of S75 grade granulated blast furnace slag powder(slag powder content is 30%～60%)is added to prepare concrete samples with different strength grades of C35～C60 that meet the standard design age of 28d.(2)High performance concrete with superfine mineral admixture(S75 grade granulated blast furnace slag powder),the strength of which is affected by water-binder ratio,superfine mineral admixture and age,etc.(3)Compared with the common cement mortar samples,the cement mortar samples with grade S75 granulated blast furnace slag powder have significantly improved the erosion resistance.The cementitious sand sample with slag powder is mainly used to improve the corrosion resistance of concrete by reducing harmful holes through aggregate filling effect.(4)This paper mainly analyzes the failure mechanism of concrete erosion mechanism by combining the two methods of electron microscopy and energy spectrum.According to the observation of electron microscope,the pore size of the common specimen without slag powder is larger than that with slag powder.Therefore,the external erosion medium is easy to invade the ordinary concrete,so that its sulfate erosion resistance becomes worse.In the later stage,the secondary hydration reaction of slag powder produces the hydration product calcium silicate CSH,which can fill and block the capillary holes,reduce the capillary clearance,increase the density of concrete,and improve the permeability and erosion resistance of concrete.