2018 Volume 67 Issue 4 Pages 468-473
The cementitious material deterioration by biogenic sulfuric acid attack in sewage environments has become a severe problem for sewage related facilities. In general, it has been said that by using blast furnace slag sand to cementitious material is improved the resistance to sulfuric acid attack. In this research, we focused on blast furnace slag sand, and investigated, on resistance to sulfuric acid attack of mortar, the influence each of chemical composition, fineness modulus and sand to cement ratio of mix proportion. As a result, we indicated that the relationship between sulfuric acid attack resistance of mortar by using blast furnace slag sand and chemical composition of CaO, and fineness modulus, and sand to cement ratio of mix proportion, was a linear, respectively. We also indicated that sulfuric acid attack resistance of mortar by using blast furnace slag sand was improved larger chemical composition of CaO, smaller fineness modulus and larger sand to cement ratio, respectively. We found that by a change of 1% in chemical composition of CaO, by a change of 1.00 in fineness modulus and by a change of 1.0 in sand to cement ratio were changed the mortar weight loss of about 5%, about 13% and about 2.6～3.7%, respectively. Moreover, from the result of multiple linear regression analysis, it was clear that fine particle of under 0.3mm of blast furnace slag sand was improved the sulfuric acid attack resistance of the mortar.
