JP6378873B2 - Artificial ground and construction method of artificial ground - Google Patents

Description

  The present invention relates to an artificial ground and a construction method for an artificial ground.

  Patent Documents 1 to 4 disclose a technique of reclaiming and compacting a recycled material obtained by recycling demolished concrete generated by demolishing an existing structure and using it as a support ground or a construction ground.

  In Patent Document 5, the base plate part and the basement outer wall of the basement structure part and the structure part that supports them in a self-supporting state are dismantled to leave at least the basement part, the base plate part, the basement outer wall, and the structure part. There is disclosed a technique for rebuilding a building in which fluidized soil is poured into a space portion of a configured underground residual portion to construct an integral foundation ground and a new building is constructed on the foundation ground.

  Here, pillars, beams, walls, etc. remain in the space of the remaining part of the underground structure of the existing structure. In particular, the space (pit portion) on the bottom plate is surrounded by the foundation beam. Therefore, it is very inefficient to backfill with recycled materials including demolished concrete and compact with heavy machinery or human power. In addition, just refilling with fluidized soil requires not only the cost of fluidized soil, but also the cost of carrying out and disposing of demolition concrete, which increases costs.

  Therefore, it is required to construct an artificial ground planned shallower than the underground structure of an existing structure efficiently and at a low cost.

Japanese Patent Application Laid-Open No. 2006-124962 JP 2010-189960 A JP 11-336335 A JP-A-11-350746 Japanese Patent Laid-Open No. 2007-170070

  An object of the present invention is to efficiently and inexpensively construct an artificial ground planned shallower than an underground structure of an existing structure.

The invention of claim 1 includes a first layer forming step of forming a first layer by pouring fluidized soil into the space above the bottom base of the underground structure of the dismantled existing structure, and on the first layer. A second layer forming step of forming a second layer obtained by laminating a compacted layer obtained by backfilling and compacting a recycled material including demolished concrete generated by dismantling of the existing structure, and on the bottom plate part There is a slab, and in the first layer forming step, a hole is formed in the slab, and the fluidized soil is poured from the hole into the space between the slab and the bottom plate part, and the second layer is formed. In the forming step, an artificial ground construction method in which the slab is disassembled and the recycled material including the dismantled concrete is backfilled.

  In the invention according to claim 1, in the first layer forming step, in the space on the bottom base of the underground structure of the existing structure, for example, the foundation beam remains, but by pouring the fluidized soil, A first layer is formed in which a recycled material including demolished concrete generated by demolishing an existing structure can be backfilled.

And, on this first layer, by forming a second layer in which the reclaimed material containing demolished concrete is backfilled and compacted , the artificial ground is easily and inexpensively formed on the bottom plate. It can be constructed, and the cost of carrying out and disposing of demolition concrete is suppressed.

  Therefore, the artificial ground planned shallower than the underground structure of the existing structure can be efficiently constructed at low cost.

The invention of claim 2 includes a first layer forming step of forming a first layer by pouring fluidized soil into a space above the bottom base of the underground structure of the dismantled existing structure, and on the first layer. have a, a second layer forming step of forming a second layer formed by laminating a clamping solid layer compacted back fill the recycled material comprising a demolition concrete generated by dismantling of the existing structure, the second layer formed In the step, the second layer is formed such that the upper layer surface is located above the planned flooring level, and the second layer is used on the second layer after the second layer forming step. It has a construction ground forming step of backfilling recycled material having a particle size larger than the recycled material to form a construction ground, and after the construction ground forming step, the construction ground and the upper part of the second layer are at the level with the planned floor. An artificial ground construction method that has an excavation process that excavates to a minimum.

  In the invention according to claim 2, in the first layer formation step, the space on the bottom base of the underground structure of the existing structure has, for example, foundation beams remaining, but by pouring the fluidized soil, A first layer is formed in which a recycled material including demolished concrete generated by demolishing an existing structure can be backfilled.

And, in the second layer formation step, artificial ground can be easily formed on the bottom plate by forming a second layer in which recycled material containing demolition concrete is backfilled on this first layer and a compacted compacted layer is laminated. In addition, it can be constructed at low cost, and the cost of carrying out and disposal of demolition concrete is suppressed.

Therefore, Ru can be constructed efficiently in low cost planned artificial ground underground precursor shallower existing structures.

  ADVANTAGE OF THE INVENTION According to this invention, the artificial ground planned shallower than the underground frame of the existing structure can be constructed | assembled efficiently at low cost.

It is sectional drawing which shows the state which constructed the construction ground by refilling the reclaimed material further on the artificial ground planned shallower than the underground frame of the existing structure, and this artificial ground. FIG. 7 is a cross-sectional view of a state in which an existing structure is dismantled while leaving a part of the underground frame including the bottom plate part shown in FIG. 6. It is sectional drawing of the state which poured the fluidization process soil into the space part between the slab of a underground frame, and a bottom board part from the state of FIG. FIG. 4 is a cross-sectional view of a state in which a second layer is constructed by backfilling with a recycled material on the first layer in FIG. 3. It is sectional drawing of the state which excavated from the state of FIG. 1 to a plan flooring level, and constructed the new construction structure. It is the whole figure which shows typically the state where the existing structure was demolished leaving a part of the underground frame including the bottom board part.

<Artificial ground and construction method of artificial ground>
An artificial ground and an artificial ground construction method according to an embodiment of the present invention will be described in a process of constructing an artificial ground shallower than an underground structure of an existing structure.

  As shown in FIG. 6, an existing structure 10 made of reinforced concrete (or made of steel reinforced concrete) having an underground frame (underground structure portion) 12 composed of a plurality of floors is constructed on the ground 80. Then, the existing structure 10 is disassembled, and a new structure 150 (see FIG. 5) is newly constructed. The underground planned floor level L of this new structure 150 (see FIG. 6) is planned to be shallower than the underground structure 12 of the existing structure 10.

  First, as shown in FIGS. 6 and 2, the existing structure 10 is disassembled with a weight-removing machine, leaving a part of the underground skeleton 12 including the bottom board portion 14.

  As shown in FIG. 2, a core (hole) 18 is formed in the slab 16 of the underground frame 12. Then, as shown in FIG. 3, fluidization processing is performed by a pump (not shown) from the core 18 of the slab 16 of the underground skeleton 12 to the space 20 (see also FIG. 6) between the slab 16 and the bottom plate part 14. Pour the soil 30 and harden. The layer constructed with the fluidized soil 30 is referred to as a first layer 102.

  The fluidized soil 30 is a backfill material having fluidity produced by kneading soil to be treated such as soil or earth and sand, cement and water with a fluidized soil production apparatus. Therefore, although there are pillars, beams, walls, and the like of the underground frame 12 in the space portion 20, the fluidized soil 30 has fluidity, so every corner of the space portion 20 between the slab 16 and the bottom plate portion 14. Can be refilled quickly. Also, compaction is not necessary.

As shown in FIG. 1 , the slab 16 (see FIG. 3) is disassembled, and a recycled material 40 including demolition concrete and recycled crushed stone generated by dismantling the existing structure 10 (see FIG. 6) Back-filling is performed, and the compaction second layer 106 is constructed by performing a rolling operation. The upper surface 106A of the second layer 106 is positioned above the planned floor level L. In the present embodiment, the second layer 106 is constructed by forming 11 layers of the compacted layer 104 compacted to a thickness of about 30 cm.

  The first layer 102 composed of the fluidized soil 30 and the second layer 106 composed of a plurality of (11 layers in this embodiment) consolidated layers 104 composed of the recycled material 40 are used in the present invention. An artificial ground 100 according to an embodiment is configured.

Further, as shown in FIG. 4, the recycled material 42 is backfilled on the second layer 106. And various construction work is performed on the construction ground of the recycled material 42 buried back on the artificial ground 100. The recycled material 42 has a larger particle size than the recycled material 40 used for the second layer 102. Further, the recycled material 42 to be backfilled on the second layer 106 is not compacted (it is not necessary to compact).

  As shown in FIG. 5, when the new structure 150 is constructed, the reclaimed recycled material 42 (construction ground) and the upper part (part) of the second layer 106 of the artificial ground 100 are excavated to the planned floor level L. To do. And the direct foundation 152 which makes the level L with a plan floor the lower end is constructed, and the new structure 150 is constructed. In the present embodiment, the foundation of the new structure 150 is a pile draft foundation having a direct foundation 152 and a pile (not shown).

<Action and effect>
Next, the operation and effect of this embodiment will be described.

  For example, pillars, beams, walls, and the like remain in the space 20 above the bottom plate portion 14 of the underground structure 12 of the existing structure 10, but by disposing the fluidized soil 30, the existing structure 10 is disassembled. As a result, the first layer 102 capable of backfilling the recycled material 40 including the demolished concrete generated by the above is formed.

  Then, by refilling the recycled material 40 including demolition concrete on the first layer 102 and compacting it to form the second layer 106, the new structure 150 can be supported on the bottom plate portion 14. A possible artificial ground (supporting ground) 100 can be easily constructed at low cost, and the amount and amount of dismantled concrete carried out are reduced. As a result, the carrying-out cost and the processing cost are suppressed.

  Therefore, the artificial ground (support ground) 100 where the planned floor level L is planned shallower than the underground structure 12 of the existing structure 10 can be efficiently constructed at low cost.

  Here, the demolished concrete generated by the dismantling of the existing structure 10 is carried out from the construction site by a truck. When this construction site is a downtown area, a business area, or a neighborhood of a residential area, the traffic of the truck may be restricted. If the truck is restricted in this way, it takes a lot of time to carry out the demolished concrete, which affects the construction period. However, by applying the present invention, it becomes possible to use the reclaimed material 40 including demolition concrete for the artificial ground 100, reducing the amount of demolition concrete carried out, and restricting the passage of the truck. Influence is suppressed.

<Others>
The present invention is not limited to the above embodiment.
INDUSTRIAL APPLICABILITY The present invention can be applied to all artificially constructed construction ground planned shallower than an underground structure of an existing structure.
Moreover, it cannot be overemphasized that it can implement with a various aspect in the range which does not deviate from the summary of this invention.

10 Existing structures
12 underground building
14 Bottom board
20 Space (space)
30 Fluidized soil
40 Recycled material 100 Artificial ground 102 First layer 106 Second layer

Claims (2)

  A first layer forming step of forming a first layer by pouring fluidized soil into the space above the bottom base of the underground structure of the dismantled existing structure;
  A second layer forming step of forming a second layer obtained by laminating a compacted layer backfilled with a reclaimed material including demolished concrete generated by dismantling of the existing structure on the first layer;
  Have
  There is a slab on the bottom board,
  In the first layer forming step, a hole is formed in the slab, and the fluidized soil is poured from the hole into the space between the slab and the bottom plate part,
  In the second layer forming step, the slab is disassembled and the recycled material containing the dismantled concrete is backfilled.
  Construction method for artificial ground. A first layer forming step of forming a first layer by pouring fluidized soil into the space above the bottom base of the underground structure of the dismantled existing structure;
A second layer forming step of forming a second layer obtained by laminating a compacted layer backfilled with a reclaimed material including demolished concrete generated by dismantling of the existing structure on the first layer;
I have a,
In the second layer forming step, the second layer is formed so that the upper layer surface is located above the planned floor level,
After the second layer forming step, it has a construction ground forming step in which a reclaimed material having a particle size larger than the reclaimed material used for the second layer is refilled on the second layer to form a construction ground.
After the construction ground formation step, the excavation step of excavating the construction ground and the upper part of the second layer to the planned flooring level,
Construction method for artificial ground.

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