INFLUENCE OF WATERPROOFING ADMIXTURE IN WATER PENETRATION OF CONCRETE

Nowadays, concrete plays an outstanding role in construction industry and variety of engineering infrastructures such as bridges, dams, jetties, piers and channels which are made of concrete. Since from one hand, these huge and critical concrete structures in which some cases are of lifelines of a country are of great importance and on the other hand, the necessity of conservation and durability of these structures is inevitable, the importance of concrete durability will become vividly apparent. One of the factors that can deteriorate the reinforced concrete condition by corrosion and cause cracking in severe cold weather, has turned out to be water penetration into concrete. With this respect, one of the practical and efficient ways ever used to countermeasure this situation is to use water proof additives in concrete mix in order to reduce water and waste water absorption and penetration into concrete. In this investigation, PN gel, PN liquid and PN liquid along with micro silica powder as waterproofing additives, were used in separate mix designs to make specimens and then these specimens and the witness were tested by two methods in order to determine water absorption and penetration depth in concrete. in one of these two methods, water absorption percentage was just determined and in the other one which was more accurate and was implemented by triaxial apparatus, both water absorption and penetration depth in the specimens were investigated. Finally, the tables and diagrams for gained results concerning specimens containing PN additives and witness were prepared and compared. The results showed about more than 50% improvement in water penetration reduction.

کلیدواژه ها:

concrete ، durability ، waterproof additives ، penetration depth ، water absorption