JP6043574B2 - Caisson method - Google Patents

Description

  The present invention relates to a caisson method for constructing an underground structure.

  The earth retaining method and the caisson method are known as methods for constructing underground structures such as a skyscraper having a basement and an underground parking lot. The caisson method has the merit that the temporary construction cost is lower than the earth retaining method and less excavation than the required volume is required. In addition, the caisson method, which is free from noise and vibration and can be constructed close to the boundary of the site, is optimal in urban areas where there is no room on the site. However, in the caisson method, the caisson often tilts during subsidence because the soil properties and excavation around the edge of the caisson are not uniform. Therefore, as a method of correcting the inclination of the caisson, a method of correcting using a hydraulic jack (JP-A-6-108473), a method of correcting using an expansion / contraction mat (JP-A-2004-44242), blade edge A method (Japanese Patent Application Laid-Open No. 2004-92275) for correcting by changing the direction of the part has been proposed.

JP-A-6-108473 JP 2004-44242 A JP 2004-92275 A

  If the caisson tilts during subsidence, the excavation of the soil around the edge of the caisson on the lower side of the caisson is stopped, and the soil around the edge of the caisson on the lower side of the caisson, i.e. If you try to correct the slope of the caisson by excavating the caisson, the plasticity of the soil will compact the soil on the side that settles earlier, the higher side of the caisson will rise further, and the slope of the caisson will increase further . In addition, the method described in the prior art document has a problem that a load is applied to the caisson housing for forcibly correcting the inclination of the caisson and a cost is required because a special device is used. Accordingly, an object of the present invention is to provide a caisson method that realizes a method capable of easily correcting the inclination of the caisson at low cost.

The caisson method according to the invention of claim 1 is a caisson method capable of correcting the inclination of the caisson, and when sinking the caisson, excavating the soil around the edge of the caisson to form a hole, The outside of the caisson is excavated from the hole to form a gap between the outer peripheral wall and the earth wall of the caisson, and the polystyrene foam is inserted into the gap from the hole.

The caisson method according to the invention described in claim 2 is a caisson method for correcting the inclination of the caisson, and when the caisson is inclined when the caisson is lowered , the caisson method around the blade edge portion of the lower caisson Excavating the soil to form a hole, excavating the outside of the caisson from the hole to form a gap between the outer wall of the caisson and the earth wall, and inserting polystyrene foam into the gap from the hole Features.

  According to the present invention, even when the caisson is inclined during the settlement, the cushioning material such as styrene foam inserted between the outer peripheral wall and the earth wall of the caisson compresses and repels, so that If the excavation of the soil around the edge of the caisson on the lower side is stopped and the soil around the edge of the caisson on the slower side, that is, the caisson on the higher side is excavated, the inclination of the caisson can be easily corrected. it can. Further, since the cushioning material such as polystyrene foam is very inexpensive, it is possible to correct the inclination of the caisson at low cost. In addition, even after the underground structure is constructed, the cushioning material is interposed between the structure and the earth wall, thereby providing a horizontal seismic isolation effect. Since the cushioning material is in the ground, there is no quality deterioration due to ultraviolet rays, and it has a seismic isolation effect for a long time.

It is sectional drawing which showed a mode that the buffer material was inserted in the clearance gap between the outer peripheral wall of a caisson, and a soil wall. It is sectional drawing which showed the mode when correcting the inclination of the caisson which inclined during subsidence. It is sectional drawing which showed the mode when a box-type structure was constructed. It is sectional drawing which showed the mode when the inner side of a box-type structure was covered with the waterproof film, and the underground structure was constructed inside the said box-type structure. It is sectional drawing which showed a mode that the buffer material was inserted in the clearance gap between the outer peripheral wall of a caisson and the earth wall inclined during subsidence.

  The present invention will be described below with reference to the drawings. First, a first embodiment of the present invention will be described. FIG. 1 is a cross-sectional view showing a state where a cushioning material is inserted into a gap between an outer peripheral wall and a soil wall of a caisson. The soil around the edge portion 11 of the caisson 1 is excavated to form a hole 3, and the soil outside the outer peripheral wall 12 of the caisson 1 is excavated from the hole 3 to form a gap 4 between the outer peripheral wall 12 and the soil wall 5. Form. The cushioning material 2 is inserted into the gap 4 from the hole 3. The above operation is repeated from the start of sinking of the caisson 1 until the caisson 1 reaches a predetermined depth. The buffer material 2 may be a slab type or a block type. The width of the gap 4 is preferably about 20 cm. The caisson 1 may have any shape such as a cylindrical shape or a rectangular tube shape.

  FIG. 2 is a cross-sectional view showing a state in which the inclination of the caisson inclined during subsidence is corrected. If the excavation of the soil on the lower side 13 of the caisson 1 is stopped and the soil around the cutting edge 11 on the higher side 14 of the caisson 1 is excavated to form the hole 3, the buffer material 21 is compressed and the buffer material 22 is compressed. By repelling the high side 14 of the caisson 1 sinking, the inclination of the caisson 1 can be easily corrected.

  FIG. 3 is a cross-sectional view showing a state in which a caisson reaches a predetermined depth and a bottom structure is constructed to construct a box structure. Since the cushioning material 2 is interposed between the outer peripheral wall 12 and the earth wall 5 of the box-shaped structure 6, there is a horizontal seismic isolation effect. Moreover, since the buffer material 2 is in the ground, quality deterioration due to ultraviolet rays can be prevented, and a seismic isolation effect can be obtained over a long period of time.

  FIG. 4 is a cross-sectional view showing a state in which the inside of the box-type structure is covered with a waterproof film, and an underground structure is constructed inside the box-type structure. A waterproof film 7 such as an asphalt waterproof material is applied to the inside of the box-type structure 6, and an underground structure 8 is constructed inside the box-type structure 6. The underground structure 8 is waterproofed from the outside by the waterproof film 7 and can be completely waterproofed.

  Next, a second embodiment of the present invention will be described. FIG. 5 is a cross-sectional view showing a state in which a cushioning material is inserted into the gap between the outer peripheral wall of the caisson inclined during subsidence and the earth wall. While caisson 1 is sinking horizontally, soil around blade edge 11 of caisson 1 is excavated to form hole 3, and caisson 1 is allowed to sink without forming gap 4. When the caisson 1 tilts during subsidence, the outer side of the outer peripheral wall 12 of the caisson 1 is excavated from the hole 3 formed below the lower side 13 of the caisson 1 and a gap 4 is formed between the outer peripheral wall 12 and the earth wall 5. And the cushioning material 2 is inserted into the gap 4. If the excavation of the soil on the lower side 13 of the caisson 1 is stopped and the soil around the cutting edge 11 on the higher side 14 of the caisson 1 is excavated to form the hole 3, the cushioning material 2 is compressed and the inclination of the caisson 1 The high side 14 of the caisson 1 sinks while correcting. Note that the cushioning material 2 may be inserted by forming a gap 4 on the outside of the high side 14 of the caisson 1. The gap 4 is formed until the caisson 1 is corrected, and the caisson 1 is lowered while the buffer material 2 is inserted. When the caisson 1 becomes horizontal, the formation of the gap 4 and the insertion of the buffer material 2 are stopped. When caisson 1 tilts again, the above operation is repeated. The buffer material 2 may be a slab type or a block type. The width of the gap 4 is preferably about 20 cm. The caisson 1 may have any shape such as a cylindrical shape or a rectangular tube shape.

Hereinafter, the example which implemented this invention by the open caisson method is shown. A bottomless caisson 1 made of reinforced concrete was constructed on the ground. The foam packaging material of household appliances was recycled and used as the buffer material 2. Asphalt waterproof material was used as the waterproof membrane 7. The hole 3 was formed by excavating the soil around the edge 11 of the caisson 1 by about 30 cm. When the caisson 1 tilts while sinking, a gap 4 with a width of about 20 cm is formed between the outer peripheral wall 12 of the caisson 1 and the earth wall 5 by digging the outside of the caisson 1 from the hole 3 with a scoop. The styrofoam was inserted into the gap 4 from the hole 3 using a hand. After the excavation of the soil on the lower side 13 of the caisson 1 is stopped and the soil around the blade 11 on the higher side 14 of the caisson 1 is excavated to form the hole 3, the styrofoam is compressed to correct the inclination of the caisson 1. However, the high side 14 of caisson 1 sank. The above operation was repeated until caisson 1 was horizontal. When the caisson 1 reached a predetermined depth, the bottom structure was leveled, the bars were placed, and concrete was placed to construct a box structure 6. After the asphalt waterproofing material was applied to the inside of the box structure 6, the underground structure 8 was constructed inside the box structure 6. Since polystyrene foam was recycled and used as the buffer material 2, the cost was low, and it was easy to correct the inclination of the caisson 1 during subsidence. Moreover, in the building constructed above the underground structure 8, there is almost no vibration of the earthquake. Further, the asphalt waterproofing material is applied to the inside of the box-shaped structure 6 so that the underground structure 8 is completely waterproofed.

1 Caisson 11
The edge of caisson 1 12 The outer wall of caisson 1 13 The low side of caisson 1 14 The high side of caisson 1 2, 21, 22 Cushioning material 3 Hole 4 Gap 5 Earth wall 6 Box structure 7 Waterproof film 8 Basement structure

Claims (2)

A caisson method capable of correcting the inclination of the caisson, and when sinking the caisson, excavating the soil around the edge of the caisson to form a hole, and excavating the outside of the caisson from the hole to form the caisson A caisson method characterized in that a gap is formed between the outer peripheral wall and the earth wall, and polystyrene foam is inserted into the gap from the hole. A caisson method for correcting the inclination of the caisson, in the case where the caisson is inclined when sinking the caisson, excavating the soil around the edge of the caisson on the lower side to form a hole, the hole The caisson method is characterized in that the outside of the caisson is excavated to form a gap between the outer peripheral wall and the earth wall of the caisson, and polystyrene foam is inserted into the gap from the hole.

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