JPH0978845A - Jacking-up method of existing building - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the positional shifting of an existing building due to strong wind or earthquakes, by lifting a footing beam by jacks after the lower foundation of the existing building has been separated from the ground side and installing a temporary foundation under the lower foundation to support it by a temporary base. SOLUTION: When an existing building is required to jack up for repair or expansion of the building, a footing beam 3 is supported by lifting-up jacks 8 and the lower foundation 2 of the building is separated from the ground side. The separated lower foundation 2 is supported by a temporary frame 12 installed on a temporary foundation 11 and the height of the temporary frame is adjusted in accordance with the height pushed up by the lifting-up jacks 8. The construction works are carried out in the state the existing building is raised and the building is prevented from positional shifting even when horizontal forces act thereon in this raised state owing to strong wind or earthquakes or the like. In this way, jacking-up of en existing building can be efficiently exerted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a jack-up construction method for separating a foundation of a lower part of an existing building such as a building from a foundation on a ground side and lifting it to a required height to carry out a necessary construction.

[0002]

2. Description of the Related Art In recent years, in order to improve the seismic performance of an existing building, a seismic isolation device has been installed in the lower part of the foundation of the existing building, or the existing building is further lifted and the lower part is used as a basement. Is required.

Here, in order to carry out such a construction, it is necessary to jack up the existing building to a required height and hold the state, but as the jacking-up construction method, the foundation of the lower part of the existing building is used. It is considered to separate it from the ground side foundation such as foundation pile and push it up with a jack.

[0004]

However, in the conventional lift-up work using the jack, the building is simply pushed up by the jack inserted in the lower part of the building to hold it at a required height, or after it is pushed up. Since it is only placed on the support work, it cannot withstand horizontal forces such as strong winds or earthquakes, and there is a risk of displacement if an excessive horizontal force is received.

If it is a short-term work, there is little possibility of encountering such a positional deviation, but the construction period of the lower structure is long, and it is applicable during the construction period. In order to maintain the jacked-up state while the building is in service, it is necessary to adopt a construction method that fully considers the maintenance measures for these.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a jacquard construction method for an existing building which can sufficiently resist the horizontal force applied to the jacked up existing building.

[0007]

In order to achieve the above object, in the jack-up method according to claim 1 of the present invention, the lower foundation of an existing building is separated from the ground side, and the existing building is jacked up to a required height. In the construction method
A pair of jack pedestals arranged on both sides of appropriate points of the underground girder of the existing building, a support body that is between the jack pedestals and serves as a reinforcing member for supporting the lower part of the underground girder, and each jack pedestal With a lift-up jack arranged above and suspending the support body, the support body is lifted by the lifting operation of the lift-up jack, and a temporary foundation is provided below the lower foundation of the existing building, By providing a temporary stand surrounding the lower foundation on the temporary foundation and engaging with the lower foundation, and supporting the horizontal force applied to the existing building via the temporary stand on the ground side, Underground beam rises in the state of being placed on the ground, and when an excessive horizontal force is applied, the temporary mount yields and deforms,
It has a seismic isolation effect, reducing the input to the rising existing building,
Obtains resistance to horizontal force.

The jack-up construction method according to claim 2 of the present invention is a construction method in which the lower foundation of an existing building is separated from the ground side and the existing building is jacked up to a required height. A plurality of push-up jacks are arranged, the lower foundation is raised by the raising operation of the push-up jacks, and a temporary stand that surrounds and engages with the periphery of the lower foundation is provided on the temporary foundation. By supporting the horizontal force applied to the existing building through the temporary mount on the ground side, the reaction force against the horizontal force can be obtained as described above.

In the jack-up method according to the third aspect of the present invention, the buttress frame is arranged around the existing building through a damper for shock absorption, so that when the building is moved, input is made by the shock absorbing damper. Can be reduced, and thus double security can be obtained.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the accompanying drawings.

1 to 3 show a construction procedure according to a first embodiment of the method of the present invention.

First, as shown in FIGS. 1 and 2, the lower part of an existing building is a lower foundation 2 and a foundation 2 installed on a foundation pile 1.
Consists of underground beams 3 that intersect in a cross shape, and pillars 4 are integrally erected on the foundation 2 and the upper part of the pillar 4 is located on the second floor 2FL.
Are connected to the beams and floor slabs that make up the floor. A slab that constitutes the first floor 1FL is integrated on the underground beam 3.

In the construction, first, the periphery of the foundation 2 is dug down, and the temporary base 5 is placed under the arbitrary underground beam 3 close to the foundation 2.
And installing a pair of gate-shaped jack mounts 6 on the temporary base 5 with both sides of the underground beam 3 sandwiched therebetween.
A support 7 having an inverted trapezoidal shape that also serves as a beam reinforcement is integrally provided below the underground beam 3 between the jack mounts 6. The support body 7 is integrally constructed in the lower portion of the underground beam 3 by a steel frame or the like.

Next, a lift-up jack 8 is installed in the center of each jack rack 6, a lift-up rod 9 penetrating the center of the jack rack 6 is hung down to the lower side of the jack rack 6, and the lower end of the lift-up rod 9 is set as described above. The jack-up preparation work is completed by fixing the support beam 10 to the support beam 10 which is arranged below the support body 7 in a crossed manner.

Although only one place is shown in the figure, the above jack equipment is arranged for each foundation 2.

After that, the foundation pile 1 and the foundation 2 are separated from each other, the temporary foundation 11 is installed on the foundation pile 1, and the temporary foundation 1 surrounding the foundation 2 is further provided on the temporary foundation 11.
2 is arranged. The temporary pedestal 12 is a truss-shaped one in which vertical and horizontal frames 12a and 12b made of H-shaped steel are assembled in a turret shape to cover the periphery of the foundation 2 and brace members 12c are laid around the frame. The base 2 is guided to rise by extending upward.

After the above preparatory work, the jacks 8 are driven all at once, and the lift-up rod 9 is pulled up, so that FIG.
As shown in, the support 7 connected to this can be pulled up, and the foundation 2 and the underground beam 3 can be moved up.

The ascending stroke for each ascending operation depends on the length of the lift-up wire 9, but the stroke can be made extremely large as compared with the case where the jack 8 directly pushes up. In addition, when the ascending work is naturally performed by adjusting the jack-up speed and the ascending stroke of each jack 8 while measuring the verticality and the horizontalness of the building, it is possible to prevent the unevenness of each part of the building.

At this time, as shown in FIG. 3, a frame 12b and a brace member 12c in the lateral direction are additionally installed and reinforced in accordance with the rise of the foundation 2 on the temporary pedestal 12 around.
When it is further raised, the temporary pedestal 12 is extended upward to be additionally installed, the individual jack pedestals 6 are also raised, and the spacers are inserted between the respective jack pedestals 6 and the temporary base 5, so that FIG. The jack-up standby state is entered, and by repeating the jack-up work in the same manner as the scale-like insect, the existing building can be jacked up to a desired height position.

In the above-described series of work steps, the building is most unstable at the time when the ascending work is completed, but the periphery of the lower foundation 2 is engaged with the temporary pedestal 12 provided on the temporary foundation 11, and the supporting body is supported. Due to the reinforcing effect of 7 and the support 7 itself being supported by the jack stand 6 in a state of sandwiching both sides, even if lateral force such as wind or earthquake is applied to the building, it can be countered. In addition, when a horizontal force larger than expected is applied, the temporary pedestal 12 surrounding the foundation 2 yields and lowers the rigidity, so that a kind of seismic isolation effect is produced and the input to the existing building is reduced. When the existing building is lifted up by one layer and the lower part is newly used as a basement or the like, the temporary pedestal 12 can be used as a constituent member of the main installation pillar.

4 to 6 show a second embodiment of the present invention. The same portions as those described above will be denoted by the same reference numerals, and different portions will be described by using different reference numerals.

In the figure, a support 30 also serving as a reinforcement is arranged at the bottom of the foundation 2, and a temporary foundation 31 is constructed so as to surround the periphery of the foundation pile 1. The temporary foundation 31 and the support 30 By arranging the four push-up jacks 32 between them, the jack-up preparation work is performed, and the foundation 2 is raised by driving each jack 32. Further, the temporary stand 12 is arranged on the temporary foundation 31 and surrounds the periphery of the foundation 2.

Although the jack stroke is short, as shown in FIG. 6, a spacer 33 is interposed between the temporary foundation 31 and the jack 32 for each ascending operation, and the temporary foundation 31 is placed on the temporary foundation 31 every time the ascending distance becomes large to some extent. FIG. 7 shows an example of the third embodiment of the present invention in which the safety girder 34 can be stacked and the ascending work can be performed with safety. In parallel with the preparatory work, the buttress frames 40 are constructed at a plurality of locations around the existing building, and the buttress frames 40 are opposed to the existing building with a small gap between them through the fender 41 that constitutes the shock absorber. .

The buttress frame 40 is made of a combination of H-shaped steels, and is a portal frame 40a vertically fixed on a temporary foundation 42 which is located on the side surface of the existing building and extended to the outside thereof. Oblique girders 40b slantingly supported on the back surface of the gate-shaped frame 40a and supporting the same, and the oblique girders 4
Brace material 4 hung between 0b and the portal frame 40a
0c and a horizontal force receiving member 40d vertically fixed to the center of the front surface of the portal frame 40a.

The fender 41 is fixed to the outer side of the foundation 2,
It is opposed to the horizontal force receiving portion 40d with a slight gap maintained. At the time of maximum lift up, the foundation 2 rises to the position of the imaginary line in FIG. 7, but the height of the horizontal force receiving member 40d corresponds to this, and the horizontal force of the existing building 1 is at any height position. It is adapted to be transmitted to the buttress frame 40 via the fender 41.

In the figure, the fender 41 is used as the base 2
It is fixed to the outer side of the building and can hit the horizontal force receiving member 40d side regardless of the height of the existing building, and when the fender 41 is provided over the entire length of the horizontal force receiving member 40d. It is economically advantageous in comparison.

Therefore, in any of the embodiments, when a horizontal force such as a strong wind or an earthquake is applied to the existing building during construction, the temporary pedestal 12 holds the existing building on the ground against the horizontal force F. . In addition, when a horizontal force more than expected is applied, the temporary pedestal 12 itself yields and lowers the rigidity, so that a kind of seismic isolation effect is produced and the input to the existing building is reduced.

Further, when the existing building moves as a result of this, the buttress frame 40 receives it by way of the fender 41, and the buffering effect of the fender 41 reduces the horizontal energy acting on the existing building while reducing the position. The deviation will be suppressed.

[0029]

As described above in detail with reference to the embodiments, according to the jack-up construction method for an existing building according to claim 1 of the present invention, the horizontal force such as strong wind, earthquake, etc., during the lift-up period of the existing building. Even if the horizontal force is applied, the horizontal force can be supported on the ground side through the temporary pedestal, and a resistance force against the horizontal force can be obtained. Further, when an excessive horizontal force is applied more than expected, the temporary pedestal yields and deforms, thereby exhibiting a seismic isolation effect and reducing the input to the existing building that is rising. In addition, there is a feature that the lifting stroke is large due to one jack-up work.

According to the second aspect of the present invention, since a general push-up jack can be used, the preparation work is simplified in addition to the above effects.

According to the third aspect of the present invention, when the existing building is moved by an excessive horizontal force,
This can be received by a buttress frame arranged around the existing building via a damper for buffering, and the buffering action of the damper can reduce the input to the existing building,
Further safety can be secured.

Therefore, according to these inventions, the safety can be ensured even when the existing building is held in the lifted-up state for a long time, and the existing building can be used even during the construction period.

[Brief description of drawings]

FIG. 1 is a side sectional view of a main part according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view taken along arrow A in FIG.

FIG. 3 is a side sectional view of an essential part showing a state after a jack-up work in the first embodiment.

FIG. 4 is a side sectional view of a main part showing a second embodiment of the present invention.

FIG. 5 is a plan sectional view of the same.

FIG. 6 is a side sectional view of an essential part showing a state after jacking up work in the second embodiment.

FIG. 7 is a side sectional view of a main part showing a third embodiment of the present invention.

[Explanation of symbols]

1 Foundation pile 2 Lower foundation 3 Underground beam 6 Jack frame 7, 20, 30 Support 8 Lift up jack 9 Lift up wire 11 Temporary foundation 12 Temporary frame 32 Push up jack 34 Reinforcing girder 40 Buttress frame 41 Fender ( Shock absorber)

Claims (3)

[Claims] 1. A method of separating a lower foundation of an existing building from a ground side and jacking up the existing building to a required height, wherein a pair of jack mounts are arranged on both sides of an appropriate portion of an underground beam of the existing building. A lift-up jack disposed between the jack mounts for supporting the lower part of the underground beam and also serving as a reinforcing member, and a lift-up jack for suspending the supports, The support is raised by the raising operation of the up-jack, and a temporary foundation is provided below the lower foundation of the existing building, and a temporary mount that surrounds and engages the periphery of the lower foundation is provided on the temporary foundation. And a horizontal force applied to the existing building through the temporary mount is supported on the ground side, and a jack-up method for the existing building. 2. A method of separating a lower foundation of an existing building from a ground side and jacking up the existing building to a required height, wherein a plurality of push-up jacks are arranged below the lower foundation of the existing building and the push-up is performed. The lower foundation is moved up by the raising operation of the up jack, and a temporary mount that surrounds and engages the periphery of the lower base is provided on the temporary base, and joins the existing building through the temporary mount. A jack-up method for existing buildings characterized by supporting horizontal force on the ground side. 3. The jack-up construction method for an existing building according to claim 1 or 2, wherein a buttress frame is arranged around the existing building via a damper for buffering.