METHOD FOR INSPECTING WATER BARRIER SHEET AND APPARATUS THEREFOR

PROBLEM TO BE SOLVED: To speedily and correctly inspect not only a joint part of a water- barrier sheet, but sheet area of a wider range at one time when a failure point of the water barrier sheet laid for the purpose of water proof of a waste disposal site, etc., is inspected at the site by a vacuum suction method. SOLUTION: In order to inspect a laid water barrier sheet at the site, the sheet is divided to a predetermined size thereby setting sheet parts 5 to be inspected, and each sheet 5 to be inspected is inspected. An inspection sheet 6 is overlapped with the sheet part 5 to be inspected, and air-extraction line- constituent materials 7 to avoid tight adhesion of upper and lower sheets are arranged between the sheet part and the inspection sheet. The air stored in a sealed space between the sheet part and inspection sheet is vacuum sucked by a suction pump 12 via a suction part 10 set at the inspection sheet, thereby turning the sealed space in a state with a reduced pressure. The pressure-reduced state is detected by a pressure reducing gage 13, whereby the presence/absence of a failure point of the water-barrier sheet is inspected.