METHOD FOR TREATING WET SURPLUS SOIL

PROBLEM TO BE SOLVED : To reduce treatment cost of highly fluid wet surplus soil discharged on the ground from the earth in the shield method or the jacking method. SOLUTION : This method for treating wet surplus soil discharged on the ground from the earth in the underground engineering works such as the shield method and the jacking method is conducted as follows. First, sodium arginate is added to the wet surplus soil as a mud additive at the time when an excavator or a propelling pipe is moved in the underground. Next, the wet surplus soil improved in fluidity by the addition of the sodium arginate is discharged on the ground. Next, calcium chloride is added to the discharged wet surplus soil to cause the added calcium chloride to react with the sodium arginate in the surplus soil to form gel where the sodium agrinate acts as a flocculant of the wet surplus soil. Next, the agglomerate generated by using the sodium arginate as the flocculant is separated from water.