WATERPROOF STRUCTURE OF CONNECTIVE PORTION OF PRECAST CONCRETE SEGMENT BLOCK

摘要

PURPOSE: A waterproof structure of a connective portion of a concrete block is provided to semi-permanently prevent water contained in the ground from permeating into a tunnel and to simplify an installation work. CONSTITUTION: A bottom face of a connective portion is waterproofed by a bentonite layer(14). A side wall and an upper face of the connective portion are waterproofed by a bentonite sheet(16). The bentonite layer or the bentonite sheet is expanded by water before the water flows in a gap of the connective portion. Thus, the water is excluded by the bentonite layer or the bentonite sheet so that the inflow of the water is blocked. In addition, even if some of the water flows in the connective portion, the water is blocked by a waterproof material.