IMPERVIOUS SHEET

摘要

PROBLEM TO BE SOLVED: To provide an impervious sheet capable of preventing the breaking. SOLUTION: Because a protective sheet 4 is joined to a sheet body 2, there is no fear that the impervious sheet 1 is broken even by being in contact with a projecting material such as rock in a conduct at the time of being pushed into the conduct. There is no fear that the impervious sheet is broken even if the projecting material is stuck into the impervious sheet 1 by the earth pressure applied after the impervious sheet 1 is pushed into the conduct.