DURABILITY AND CHEMICAL RESISTANCE OF SEWER CONCRETE CONTAINING FERRONICKEL SLAG POWDER.

Concrete sewer pipe line is one of the important civil infrastructures. Since the concrete sewer pipe is buried underground, the deterioration could be serious problem in maintenance and the repair and replacement cost is very high. The main aggressive factor affecting the durability of concrete sewer pipe is chemical attack by chloride and sulfate, so the sulfate resistant concrete should be used for the construction of sewer pipe line. In this study, the feasibility for the application of ferronickel slag powder (FSP) as a supplementary cementing material (SCM) used to improve the performance of concrete sewer pipe was investigated and the experimental tests were performed with different replacement ratio and fineness to determine the optimum level of replacement securing the improved chemical resistance and durability. The improvement of durability and chemical resistance of FSP contained mortar was verified through accelerated chloride ion penetration test, chemical resistance test and microstructural analysis. The optimum replacement rate of FSP can be considered as 40 % to assure the durability of concrete sewer pipe. [ABSTRACT FROM AUTHOR]