WATERPROOF SHEET FOR TUNNEL WITH PLURAL RECESSED GROOVES FOR DRAINING SEEPAGE WATER

摘要

PURPOSE: A waterproof sheet for a tunnel is provided to prevent the waterproof sheet from being ripped by draining seepage water through recessed grooves around the tunnel, and to restrict defect of the tunnel by preventing inflow of seepage water into the lining concrete surface. CONSTITUTION: A basic tunnel hole(3) is bored with the large semicircular section, and a shotcrete surface(4) is finished by pouring shotcrete inside the basic tunnel hole. Nonwoven fabric(7) is contacted and fastened to the shotcrete surface by arranging and fixing randelles on the nonwoven fabric. A waterproof sheet(1) is made of EVA, PVC or V-LDPE, and fastened to the randelle. A waterproof layer(5) is formed by thermal-bonding, and a lining concrete surface(6) is formed by pouring lining concrete on the waterproof sheet. Plural recessed grooves(2) are arranged in the circumference of the tunnel hole and formed in the surface of the waterproof sheet to drain seepage water from voids of the nonwoven fabric through a drain hole.