Backfill structure and backfill construction method

Abstract

An object of the invention is to realize a backfill structure suitable for relatively small-scaled land improvement without causing such a problem that a retaining wall after construction is unstable. A backfill structure for constructing an underground structure is composed of a plurality of wall face panels 1 vertically provided on a front face of a ground portion, coupling members 2 which are inserted through through-holes provided in the wall face panels to be fastened on the front face side of the wall face panels, net-like sheets 3 fastened with the other ends of the coupling members 2, and backfill soil body which is filled on the net-like sheets 3 to bury and fix the net-like sheets 3, where the backfill soil body is filled between the wall face panels 1, the back face side of the wall face panels, and the ground portion.

1 . A backfill structure for constructing an underground structure by performing backfill of excavated soil, comprising:
 a plurality of wall face panels vertically provided at predetermined intervals on a slope of a ground portion;   a plurality of sheet members attached along a height direction of the plurality of wall face panels; and   coupling members for coupling the plurality of sheet members and the plurality of wall face panels, wherein   backfill of the excavated soil is performed within the predetermined intervals, and the plurality of sheet members coupled to the plurality of wall face panels are laid and buried approximately in parallel with a ground face, respectively.   
     
     
         2 . The backfill structure according to  claim 1 , wherein the plurality of sheet members are formed in a mesh shape. 
     
     
         3 . The backfill structure according to  claim 1 , wherein the plurality of sheet members are made of steel, made of cloth, or made of resin. 
     
     
         4 . The backfill structure according to  claim 1 , wherein the lengths of the plurality of sheet members are set to the lengths of about 1/3 or more of the lengths of the wall face panels  1  in a height direction thereof. 
     
     
         5 . A backfill construction method for constructing an underground structure by performing backfill of excavated soil comprising:
 an excavating step of excavating a ground face to be subjected to backfill;   a panel-vertically-providing step of vertically providing a wall face panel on a front face of a ground portion;   a step of attaching a plurality of sheet members to the wall face panel;   a backfill step of performing backfill in a backfill portion positioned between the ground portion and the wall face panel up to laying levels of the plurality of sheet members; and   a land-leveling step of leveling land after the backfill is repeated by the number of times corresponding to the number of the plurality of sheet members.   
     
     
         6 . A backfill construction method for constructing an underground structure by performing backfill of excavated soil comprising:
 an excavating step of excavating a ground face to be subjected to backfill;   a panel-vertically providing step of vertically providing a wall face panel on a front face of a ground portion;   a step of attaching a plurality of sheet members to the wall face panel;   a backfill step of performing backfill in a backfill portion positioned between the ground portion and the wall face panel up to laying levels of the plurality of sheet members;   a surface compaction step of, after the backfill is performed up to the laying levels of the plurality of sheet members, performing surface compaction to surfaces of the laying levels; and   a land-leveling step of leveling land after the backfill step and the surface compaction step are repeatedly performed by the number of times corresponding to the number of the sheet members.   
     
     
         7 . The backfill structure according to  claim 2 , wherein the plurality of sheet members are made of steel, made of cloth, or made of resin. 
     
     
         8 . The backfill structure according to  claim 2 , wherein the lengths of the plurality of sheet members are set to the lengths of about 1/3 or more of the lengths of the wall face panels  1  in a height direction thereof. 
     
     
         9 . The backfill structure according to  claim 3 , wherein the lengths of the plurality of sheet members are set to the lengths of about 1/3 or more of the lengths of the wall face panels  1  in a height direction thereof. 
     
     
         10 . The backfill structure according to  claim 7 , wherein the lengths of the plurality of sheet members are set to the lengths of about 1/3 or more of the lengths of the wall face panels  1  in a height direction thereof.