Nuclear reactor installation in underground construction

摘要

Nuclear reactor installation in underground construction having a tunnel extending from a location at the surface of the earth to an underground concrete tank includes an auxiliary tunnel extending from a branching location of the first-mentioned tunnel to a location at the surface of the earth different than that from which the first-mentioned tunnel extends, the auxiliary tunnel having a cross section smaller than that of the first-mentioned tunnel and having means disposed therein for blocking the auxiliary tunnel, the blocking means being openable during operation of the nuclear reactor installation, the first-mentioned tunnel being substantially rectilinear and being continuously closed during operation of the nuclear reactor installation between the branching location thereof and the location at the surface of the earth from which the first-mentioned tunnel extends.