STRUCTURE OF EARTH RETAINING WALL, ITS CONSTRUCTING METHOD, AND STEEL BOX USED FOR THIS CONSTRUCTION

摘要

PROBLEM TO BE SOLVED: To facilitate the excavation just under an existing underground structure for newly constructing another underground structure by constructing an earth retaining wall by use of a steel box just under the existing underground structure such as buried pipeline, subway lining tunnel or the like. ;SOLUTION: A shaft 28 reinforced by a sheathing pile 24 and a timbering 26 is provided on the periphery of an existing underground structure 10, and a box line 14a formed by longitudinally connecting steel boxes 16 opened in both end parts to each other by bolts is pressed by a jack 30, the bedrock is excavated within the box line 14a, and the box line 14a is progressed while the excavated earth and sand are discharged through the shaft 28 to cross just under the existing underground structure. Box lines 14b, 14c are progressed in the same manner, and after the propulsion is terminated, the upper and lower steel boxes 16 are mutually connected by bolts, and concrete is filled into the steel boxes 16 as occasion demands. Two underground walls are thus constructed just under the existing underground structure, whereby excavation can be performed while reinforcing the part just under the existing underground structure between them by timberings.;COPYRIGHT: (C)1997,JPO