Experimental Study on Alkali Activated Slag Solidification of Earth Pressure Balance Shield Muck

Alkali-activated blast furnace slag is used to solidify soil pressure balance shield muck. The effects of slag content, liquid-solid ratio, alkali activator, molding pressure and curing temperature on mechanical properties of solidified earth pressure balance (EPB) shield muck were investigated. The main products of solidification reaction and microstructure of solidified muck were analyzed, and the acid and salt resistance of solidified soil was studied. The results show that alkali-activated blast furnace slag has good solidification ability for EPB shield muck. With the increase of blast furnace slag content, the compressive strength and apparent density of solidified soil increase; the main source of strength of solidified muck is C-S-H and C-A-S-H generated by alkali-activated blast furnace slag; the combined excitation of sodium hydroxide and sodium silicate has better solidification effect than single excitation molding pressure and curing temperature have certain influence on the compressive strength of solidified soil. The erosion of sodium sulfate on the prepared solidified soil is small, while that of sulfuric acid and hydrochloric acid is relatively large.