Method for constructing underground structure

Abstract

A method of building a hollow structure in an embankment during its embanking work, wherein portions inside the embankment which are to form slope or side wall layers of later excavated cavity for the structure are embanked simultaneously with remaining portion of the embankment, with a plurality of nets buried as vertically spaced and to substantially horizontally intersect sliding surfaces appearing in said layers upon excavation of the cavity, upper ceiling portion of the cavity later excavated is prestressed during further embanking work by means of at least crushed stone filling between supporting plates buried respectively above each of said slope layer portions as opposed to each other with their surface and coupled by steel wires tightly hung between them, and after completion of the embanking work the cavity is excavated by removing embanked material in a zone surrounded by the slope layer portions and prestressed ceiling portion, so that the structure can be built within the cavity with the slope layers and ceiling layer highly stably maintained as prevented from being collapsed by the nets buried in the layers and favorably interlinking with the embanked material and crushed stone layer held between the supporting plates across the cavity.