JP2009127251A - Rebuilding method of building - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable efficient construction, in rebuilding of an existing building while preventing floating of an existing base plate, by minimizing adverse effects on the circumference and reducing restrictions to the structure of a new aboveground structure part. <P>SOLUTION: In the rebuilding method of building for rebuilding an existing building to a new building B while leaving a part or all of its existing subsurface structure part A1 on which groundwater pressure acts, a new support pile 1 of the new building B is placed in the middle of disassembling of the existing building and the new support pile 1 is integrated with an existing base plate 3 of the existing subsurface structure part A1, partial construction of a new aboveground structure part B2 of the new building B is then started while ensuring a support force in the new support pile 1, and the existing subsurface structure part A1 is disassembled in a state where the total sum of an increase in load acting from the new support pile 1 on the existing base plate 3 according to the partial construction of the new aboveground structure part B2 and a drawing resistance of the new support pile 1 is a decrease in load acting on the existing base plate 3 according to the disassembling of the subsurface structure part A1 of the existing building or more to build a new subsurface structure part. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for rebuilding a building that is to be rebuilt to a new building while leaving a part or all of the existing underground structure portion of the existing building on which groundwater pressure acts.

In the rebuilding of the building, as shown in FIG. 1, when the pressurized aquifer 10 is located on the ground below the existing underground structure A <b> 1, due to the influence of the pressurized water pressure of the pressurized aquifer 10. As the load on the existing bottom board 3 decreases in the dismantling of the existing building A, there may be a concern about the phenomenon of floating and board swelling. In such a case, naturally, it is necessary to take preventive measures against the above-described lifting and boarding phenomenon.
Conventionally, there are the following methods for rebuilding this type of building.
[1] If there is room in the site, as shown in FIG. 7, a new mountain retaining impermeable wall that penetrates the pressurized aquifer 10 on the outer side of the existing building A to a deeper depth. 20 is formed, and the supply of water from the surrounding ground in the aquifer aquifer 10 is cut off to balance the vertical force at the bottom of the existing building A, and then the existing underground structure A1 How to dismantle.
[2] As shown in FIG. 8, a pumping well 21 is installed around the site or its surroundings to draw the groundwater of the confined aquifer 10 and the water pressure of the confined aquifer 10 is lowered. A method of dismantling the existing underground structure A1.
[3] As shown in FIG. 9, a plurality of piles 22 are driven into the ground so as to give resistance to the pulling force, a mega truss 23 is attached over each pile 22, and the mega truss 23 and the existing underground structure part A1 are attached. The strut member 24 is installed over the existing base 3 and the upward force applied from below through the strut member 24 is received by the rigidity of the mega truss 23 that secures the reaction force on the pile 22, and the underground structure portion A1 is received. A method of rebuilding to the new underground structure B1 (for example, see Patent Document 1).

Japanese Patent No. 3761307 (Claim 1, FIG. 2)

Of the above-mentioned conventional methods for rebuilding buildings, the method [1] requires a sufficient site for the construction of the new mountain retaining wall, and there are many buildings in the city (rooms on the site). There is a problem that it is difficult to adapt to a building with no. Moreover, generally the depth of a mountain retaining impermeable wall is often large, which tends to increase the construction process and construction cost.
In addition, according to the method [2], it is assumed that the drained groundwater has drainage facilities that can handle the drainage, and that ground subsidence due to a drop in groundwater level is assumed. There are problems such as concern.
Also, according to the method [3], a large-scale beam structure such as a mega truss is required to prevent the existing bottom plate from being lifted, and the structure of the ground structure is limited. There are problems that are difficult to apply to buildings.

  Accordingly, the object of the present invention is to solve the above-mentioned problems, and in the rebuilding in a state in which the existing bottom plate is prevented from being lifted up, it is possible to perform construction in a state in which adverse effects on the surroundings are difficult to occur, and a new ground structure part The present invention provides an economical method of rebuilding a building that is not easily restricted by the structure of the building.

  A first characteristic configuration of the present invention is a method of rebuilding a building to be rebuilt to a new building while leaving a part or all of the existing underground structure portion of the existing building on which underground water pressure acts. The new support pile of the new building is placed, and the new support pile and the existing bottom of the existing underground structure are integrated, and the support force is secured to the new support pile to The construction of a part of the new ground structure part was started, and the sum of the load increase acting on the existing bottom from the new support pile and the pulling resistance force of the new support pile with the construction of the part of the new ground structure part. However, the existing underground structure part is dismantled in a state where the amount of load acting on the existing bottom plate is equal to or greater than the dismantling of the underground structure part of the existing building, and the new underground structure part is rebuilt.

According to the first characteristic configuration of the present invention, the new support pile of the new building is placed in the middle of the dismantling of the existing building, and the new support pile and the existing bottom of the existing underground structure are integrated. In addition, since the support force is secured to the new support pile and the construction of a part of the new ground structure part of the new building is started, thereafter, as the construction of the new ground structure part is advanced, the load is It acts on the existing bottom board part from the new support pile and works effectively to suppress the existing bottom board part.
Therefore, it is possible to balance the upward force from the ground while effectively utilizing the weight of the new ground structure portion without necessarily providing a rigid mega truss in the new ground structure portion as in the prior art. As a result, it is possible to carry out the rebuilding of the building economically in a state in which the structure of the new ground structure part is not easily restricted and there is little adverse effect on the surroundings.
And with the partial construction of the new ground structure part, the sum of the load increase acting on the existing bottom plate from the new support pile and the pulling-out resistance of the new support pile is the sum of the underground structure part of the existing building. Since the existing underground structure part is dismantled in a state where the load acting on the existing bottom plate is more than the amount that has been dismantled, and the new basement part is rebuilt, the existing bottom plate is made more stable against upward force. You can keep rebuilding.

  The second characteristic configuration of the present invention is the upper end position of the existing underground structure portion when balancing with the presence of the remaining existing underground structure portion against the upward force from the ground acting on the existing bottom plate. The dismantling border depth is preliminarily determined, and the lowest layer portion of the new ground structure portion is formed at a position higher than the dismantling border depth by at least one layer.

According to the second characteristic configuration of the present invention, in addition to being able to achieve the above-described operational effects of the first characteristic configuration of the present invention, the dismantling border depth, the lowest layer portion of the new ground structure portion, The construction of the new underground structure part can be advanced at the same time as the construction of the new ground structure part in the area of one layer or more between, and the construction period can be shortened.
Furthermore, since the weight of the new underground structure part to be constructed in parallel with the new ground structure part can also act as a restraining force to the existing bottom, it is possible to proceed with rebuilding work in a safer state. Become.

  Embodiments of the present invention will be described below with reference to the drawings. In the drawings, the parts indicated by the same reference numerals as those in the conventional example indicate the same or corresponding parts.

  This embodiment shows one Embodiment of the method of rebuilding the existing building A provided with the existing underground structure part A1 as shown in FIG. 1 to the new building B shown in FIG.

  As shown in FIGS. 1 to 5, the building rebuilding method according to the present embodiment places a new support pile 1 of the new building B in the middle of dismantling the existing building A, and the new support pile 1. The existing bottom base 3 of the existing underground structure part A1 is integrated, a supporting force is secured to the new support pile 1, and a partial construction of the new ground structure part B2 of the new building B is started. With the partial construction of the structure part B2, the sum of the load increase acting on the existing bottom 3 from the new support pile 1 and the pulling resistance of the new support pile 1 is the underground structure part A1 of the existing building A. The existing underground structure part A1 is dismantled in a state where the load decreases on the existing bottom plate 3 due to the dismantling, and is rebuilt to a new underground structure part B1.

As shown in FIG. 1, the existing building A is a building to be demolished and includes an existing underground structure A1 and an existing ground structure A2.
And both the said existing underground structure part A1 and the existing above-ground structure part A2 are the structures provided with the floor of several floors.
Each floor is configured by providing a side wall portion 6 on the side surface, a floor structure portion 7, and a column structure portion 8 extending over the upper and lower floor structure portions 7.
And the said existing bottom board 3 is formed in the lowest part of the existing underground structure part A1.
Incidentally, the floor structure 7 is constituted by a slab or a beam. Moreover, the said existing base 3 is comprised with the foundation slab and the underground beam.

  Moreover, in the lower ground of the existing underground structure part A1, the highly confined aquifer 10 is located, and if the existing building A is demolished as a whole, it will return to the foundation ground part that has been operating until then. The building load is reduced, the balance with the upward pressurized water pressure of the highly pressurized aquifer 10 is lost, and there is a high risk that the foundation ground part will be lifted and the bulging phenomenon will occur.

  As shown in FIG. 5, the new structure B has a structure in which a new underground structure B1 and a new ground structure B2 are supported by a plurality of new support piles 1 in this embodiment.

Next, a specific rebuilding procedure from the existing building A to the new building B will be described.
[1] The existing ground structure A2 of the existing building A is dismantled within the range where the balance with the pressurized water pressure at the existing bottom 3 is not lost, and a new support pile 1 is hit in the existing bottom 3 of the existing underground structure A1. The guide wall G is integrally formed by filling concrete around the installation position (see FIG. 2).
[2] The new support pile 1 is constructed in the ground through the guide wall G (see FIG. 3). In the pile construction, although not shown in the figure, for example, in the pile driving position, the stand pipe is raised from the existing bottom board 3 to the work stage, and the pile construction is carried out through the inner space, so that the underground structure part Construction can be carried out in a state where the groundwater, concrete and the like accompanying the construction of the pile are prevented from flowing into the space of A1.
In addition, the new support pile 1 is integrated with the existing bottom plate 3, and a shaped steel pillar 1 a is integrally provided on the upper portion of the new support pile 1. Incidentally, the upper end portion of the structural pillar 1a is raised to a height at which it can be integrally connected to the floor structure portion 7 of the lowermost layer of the new ground structure portion B2. By this step, it is possible to cause the load acting on the new support pile 1 to act against the existing bottom plate 3 and to counter the upward pressurized water pressure.
[3] The formation of the new ground structure portion B2 is started in a state extending over the upper end portions of the respective structural pillars 1a (see FIG. 4). And the support force of new ground structure part B2 is ensured by the new support pile 1 through the said true pillar 1a. At the same time, the weight of the new ground structure B2 also acts on the existing bottom board 3. In parallel with these processes, the existing underground structure A1 is gradually dismantled and rebuilt to a new underground structure B1.
The dismantling of the existing underground structure part A1 is a dismantled body with respect to the sum of the load increase acting on the existing bottom 3 with the construction of the new ground structure part B2 and the pulling resistance force of the new support pile 1 It is implemented at a pace that maintains a relationship that does not exceed the weight.
[4] The new ground structure B2 is reconstructed into an integrated new building B while the underground structures A1 and B1 are disassembled and constructed in parallel (see FIG. 5).
In addition, you may implement new underground structure part B1 by any of a reverse driving method and a forward-plowing method.

  According to the rebuilding method of the building of this embodiment, the construction can proceed while effectively utilizing the existing underground structure part, and a new underground impermeable wall and a pumping well can be provided as in the past. Even without adopting a highly rigid structure such as a mega truss for the new ground structure part, it is possible to rebuild the structure part in a state in which the floating of the bottom plate and the board bulge phenomenon are suppressed and economically. Furthermore, it is possible to adapt even to a building where there is no room on the site, and it is possible to perform construction in a state where the influence on the surroundings hardly occurs.

[Another embodiment]
Other embodiments will be described below.

<1> The existing building A and the new building B are not limited to the configuration described in the previous embodiment, and for example, the number of layers, the arrangement and structure of pillars, and the like can be freely set. In addition, the formation of the new underground structure B1 can employ either the reverse driving method or the forward driving method.
<2> The underground structure part and the ground structure part do not mean the upper and lower structure parts strictly bounded by the ground surface, and when the new building B is constructed separately in parallel up and down, A block mainly including a hierarchy above the ground surface and a block mainly including a hierarchy below the ground surface are referred to as a new ground structure part B2 and a new underground structure part B1. Therefore, the boundary between the upper and lower structure portions does not necessarily coincide with the ground surface height.
<3> As a method of setting the height of the boundary between the upper and lower structure portions, that is, the lowermost layer portion 7a (see FIG. 6) of the new ground structure portion B2, a method of unconditionally setting the height according to the ground surface height In addition, the following setting method is given as an example.
As shown in FIG. 6, the upper end position of the existing underground structure A1 when balanced by the presence of the existing underground structure A1 remaining with respect to the upward force U from the ground acting on the existing bottom 3 The demolition border depth K is determined in advance, and the lowermost layer portion 7a of the new ground structure portion B2 is formed at a position higher than the demolition border depth K by at least one layer. By doing so, a new underground structure part is formed at the same time as the construction of the new ground structure part B2 in an area of one layer or more between the dismantling border depth K and the lowermost layer part 7a of the new ground structure part B2. Construction of B1 can be advanced and a work period can be shortened. Furthermore, since the weight of the new underground structure part B1 constructed in parallel with the new ground structure part B2 can also act as a restraining force to the existing bottom board 3, the rebuilding construction in a safer state is advanced. Is possible.
Incidentally, in determining the dismantling border depth K, the upward force U may be calculated by considering only the weight balance of the existing underground structural part A1, but the pulling resistance force of the new pile or the existing underground You may consider the frictional resistance etc. with the ground in contact with structure part A1.

  In addition, as mentioned above, although the code | symbol was written in order to make contrast with drawing convenient, this invention is not limited to the structure of an accompanying drawing by this entry. In addition, it goes without saying that the present invention can be carried out in various modes without departing from the gist of the present invention.

Cross section showing an existing building Sectional view explaining how to rebuild a building Sectional view explaining how to rebuild a building Sectional view explaining how to rebuild a building Sectional view showing the rebuilt building The conceptual diagram which shows the rebuilding method of the building of another embodiment Sectional drawing which shows the rebuilding method of the conventional building Sectional drawing which shows the rebuilding method of the conventional building Sectional drawing which shows the rebuilding method of the conventional building

Explanation of symbols

1 New support pile 3 Existing bottom A Existing building A1 Existing underground structure B New building B1 New underground structure B2 New ground structure

Claims (2)

A method of rebuilding a building that is to be rebuilt to a new building while leaving a part or all of the existing underground structure part of the existing building on which groundwater pressure acts,
During the dismantling of the existing building, a new support pile of the new building is placed, and the new support pile and the existing bottom of the existing underground structure are integrated to secure support force to the new support pile. Then, the construction of a part of the new ground structure part of the new building is started, and with the construction of the part of the new ground structure part, the load increase acting on the existing bottom from the new support pile and the new support pile Dismantle the existing underground structure in a state where the sum of the pulling resistance and the load of the existing floor is reduced due to the dismantling of the underground structure of the existing building, and rebuild to the new underground structure How to rebuild a building.   The dismantling border depth, which is the upper end position of the existing underground structure when balancing with the upward force from the ground acting on the existing bottom, is determined in advance, and the dismantling border The building rebuilding method according to claim 1, wherein the rebuilding is performed by forming a lowermost layer portion of the new ground structure portion at an upper position at least one layer above the depth.

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