JP7466244B1 - How to adjust the floor level of a building - Google Patents

Abstract

[Problem] To enable manual restoration of a floor level that has dropped due to aging deterioration of a floor structure. [Solution] A method for adjusting the floor surface level of a building includes the following first to third steps. In the first step, a worker enters the underfloor space Hd. In the second step, a worker places a hydraulic jack Uj between the bottom surface of the slab 10 to be adjusted and the top surface of the floor slab Sf, and jacks up the slab 10 with the hydraulic jack Uj, thereby moving the slab 10 upward by approximately N mm. In the third step, a worker adjusts the adjustable underfloor support fittings FS, which are no longer loaded because the slab 10 has floated, by approximately +N mm, and supports the slab 10 to be adjusted, which has moved upward by approximately N mm, by the adjustable underfloor support fittings FS, thereby raising the floor surface level by N mm. [Selected Figure] Fig. 10

Description

The present invention relates to a method for adjusting floor levels in buildings.

Conventionally, there have been under-floor support structures that allow floor level adjustment to be easily performed from under the floor (see, for example, Prior Art Document 1).
This prior art document 1 states that due to changes in the floor structure over time or due to earthquakes, etc., it may become impossible to maintain the horizontality of the floor surface, and therefore it is necessary to restore the horizontality of the floor surface (paragraphs [0004] and [0005]).
Furthermore, Prior Art Document 1 describes that, without removing the floorboards, a worker descends into the underfloor space and adjusts the level of the floor surface by rotating a pair of level adjustment bolts and lock nuts of the underfloor supports (paragraph [0028], Figure 9).

Patent No. 3742081

However, because the underfloor supports support the beams that make up the joists, it is actually difficult to move the beams upwards simply by manually rotating the level adjustment bolts and lock nuts of the underfloor supports.
In other words, it is actually difficult to restore a floor level that has dropped due to deterioration of the floor structure over time or due to an earthquake or the like.

The present invention was made in consideration of these circumstances, and aims to provide a method for adjusting the floor level of a building that can manually restore the floor level that has dropped due to deterioration of the floor structure over time, etc.

In order to achieve the above object, a method for adjusting a floor level of a building according to one aspect of the present invention includes the steps of:
A method for adjusting the floor level of a building when the floor level after construction is lowered by N mm in a building in which a plurality of reverse beams are protruding from the upper surface of the slab at intervals, a plurality of joists are supported between the opposing reverse beams, and flooring is laid on the joists via floor joists to form one or more underfloor spaces surrounded by the plurality of reverse beams,
Both ends of the joists are supported by adjustable underfloor supports whose vertical positions can be adjusted within a range of ±M mm (M is a value equal to or greater than N);
When the underfloor space has a height necessary for a worker to place a jack on the underside of the joist and the top surface of the slab and perform jacking up work,
A first step in which the worker enters the underfloor space;
A second step in which the worker places a jack between the lower surface of the joist to be adjusted and the upper surface of the slab, and jacks up the joist to be adjusted by approximately N mm in the upward direction;
A third step in which the worker adjusts the adjustable underfloor support by approximately +Nmm to support the joist to be adjusted that has moved upward by approximately Nmm with the adjustable underfloor support, thereby raising the floor surface level by Nmm;
including.

According to the present invention, floor levels that have dropped due to deterioration of the floor structure over time can be restored manually.

FIG. 2 is a cross-sectional view taken along line 2-2 of FIG. 1. FIG. 3 is an enlarged cross-sectional view taken along line 3-3 in FIG. FIG. 4 is an enlarged cross-sectional view taken along line 4-4 in FIG. FIG. 4 is an enlarged view of a portion 5 enclosed by a dashed line in FIG. 3 . FIG. 6 is an enlarged cross-sectional view taken along line 6-6 in FIG. 5. FIG. FIG. 4 is an exploded vertical cross-sectional view of the support portion of the joist. FIG. 1 shows workers crawling into the crawl space of an apartment building to carry out floor-level restoration work. This is a diagram showing the state in which a jack is placed between the underside of the joists in the underfloor space and the upper surface of the slab. FIG. 11 is a diagram showing how the jack in FIG. 10 is used to jack up the joist. FIG. 12 is a diagram showing how the level of the floor structure, which has been freed from load by jacking up the joists shown in FIG. 11 , is being adjusted. 11A and 11B are diagrams illustrating an example of another jacking up method. This is a cross-sectional view taken along line AA in FIG. FIG. 14 is a perspective view showing a joint fitting used in the jacking up method of FIG. 13.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
First, with reference to Figs. 1 to 8, a floor support structure of an apartment house to which a method for adjusting floor level of a building according to one embodiment of the present invention is applied will be described.
Figure 1 is a partially broken plan view of an apartment building, Figure 2 is a cross-sectional view taken along line 2-2 in Figure 1, Figure 3 is an enlarged cross-sectional view taken along line 3-3 in Figure 1, Figure 4 is an enlarged cross-sectional view taken along line 4-4 in Figure 3, Figure 5 is an enlarged view of the dotted line enclosed area 5 in Figure 3, Figure 6 is an enlarged cross-sectional view taken along line 6-6 in Figure 5, Figure 7 is an oblique view of the support part of the joist, and Figure 8 is an exploded longitudinal cross-sectional view of the joist support part.

In Figures 1 to 3, the concrete structure F with an inverted beam structure that constitutes the framework of the apartment building has horizontal structure parts Fh that extend horizontally and divide the building into multiple floors, and vertical structure parts Fv that extend vertically and connect the upper and lower horizontal structure parts Fh to each other.

On each floor separated by the horizontal structural section Fh, multiple residential spaces H are arranged side by side, and each residential space H is separated by structural columns 1 erected at each of the four corners and connecting the upper and lower floor slabs Sf, and structural exterior walls 2 and structural partition walls (load-bearing walls) 3 that connect opposing structural columns 1 together.

The floor slab Sf that constitutes the horizontal structural portion Fh has vertical and horizontal inverted girders 5L, 5T that protrude upward from the floor slab Sf and divide the underfloor space Hd of each residential space H. The lower ends of the structural partition walls 3 and the structural exterior walls 2 are integrally connected to these vertical and horizontal inverted girders 5L, 5T. Furthermore, these inverted girders 5L, 5T are integrally connected to the structural columns 1 located at the four corners of the residential space H.

In each residential space H, vertical and horizontal inverted small beams 6L, 6T that are lower than the inverted main beams 5L, 5T are integrally protruded upward from the floor slab Sf. These vertical and horizontal inverted small beams 6L, 6T cross each other, and their ends are integrally connected to the middle parts of the horizontal and vertical inverted main beams 5T, 5L, respectively.

In addition, a passageway 7 is constructed on the outside of one of the structural exterior walls 2 (left side in Fig. 1) of the residential spaces H of, for example, multiple parallel residential spaces H, and a balcony 8 is constructed on the outside of the other structural exterior wall 2 (right side in Fig. 1). Urethane foam 9 is provided as a heat insulating material on the inner surface of the horizontal inverted beams 5T on the passageway 7 side and balcony 8 side.

A floor structure Fr is supported between the vertical and horizontal inverted main beams 5L, 5T and the vertical and horizontal inverted small beams 6L, 6T of each residential space H, and this floor structure Fr divides the residential space H into an underfloor space (storage space) Hd and an above-floor space (living space) Hu.

As shown in Fig. 4, the floor structure Fr is integrally formed of a plurality of joists 10, a plurality of joists 11 supported perpendicularly on the joists 10, and floorboards 12 made of wood-based flooring boards or the like laid on the joists 11. The floorboards 12 are formed by integrally laminating a finishing material on a base material.
The joists 11 are wooden joists and steel joists. In the case of steel joists, it is preferable to interpose a cushioning material (soundproofing and vibration-proofing material) such as a rubber member between the joists and the joists 10. The joists 10 are formed by bending, for example, a rust-resistant galvanized steel plate into a Σ-shaped cross section, and are called Σ beams. In this embodiment, the joists 10 are exemplified by using Σ beams.

As shown in FIG. 1, each residential space H is formed in a rectangular shape in plan view, and in the direction perpendicular to its longitudinal direction, i.e., in the width direction of the residential space H, a plurality of joists 10 are supported between the relatively short spans of the vertical inverted main beams 5L and the vertical inverted small beams 6L.
As shown in Fig. 2, the side of the vertical inverted girder 5L is integrally formed with a stepped portion, i.e., a floor support portion 14, at approximately the same level as the inverted small beams 6L, 6T (formed integrally at the same time as the vertical inverted girder 5L is formed using a formwork). Between this floor support portion 14 and the upper surface of the vertical inverted small beam 6L, the ends of the multiple joists 10 are supported in a floating manner via adjustable underfloor support fittings FS.

7 and 8, this adjustable under-floor support bracket FS is made up of a galvanized steel support plate 16 bent into a pit shape, vibration-isolating rubber 17 with a concave cross section, a pair of level adjustment bolts 18, and a pair of lock nuts 22 screwed onto each of the level adjustment bolts 18. If the adjustment allowance of the adjustable under-floor support bracket FS is M, M is ±12.5 mm.
The support plate 16 has protruding portions 16a that protrude approximately horizontally on both the left and right sides. These protruding portions 16a are provided with bolt holes 16b through which level adjustment bolts 18 can pass, and weld nuts 19, concentric with the bolt holes 16b, and into which the level adjustment bolts 18 are screwed are welded to their undersides.

The anti-vibration rubber 17 is fitted into the recess of the support plate 16 with some interference, but is not joined together. The pair of level adjustment bolts 18 have hexagonal heads 18b at their lower ends. Hereinafter, these heads 18b will be referred to as hexagonal heads 18b.
A circular seating plate 20 is welded to the underside of each of the hexagonal heads 18b. A disk-shaped cushioning rubber 21 is bonded to the underside of the seating plate 20.

Next, a procedure for supporting the joists 10 on the support surface of the concrete framework F or on the vertical inverted small beams 6L using this adjustable underfloor support bracket FS will be described.
The male threads of the pair of level adjustment bolts 18 are screwed into the pair of weld nuts 19 and passed through the bolt holes 16b, so that the male threads of the pair of level adjustment bolts 18 are screwed into the left and right protruding parts 16a of the support plate 16, respectively, and lock nuts 22 are screwed onto the free ends of the male threads protruding from the left and right protruding parts 16a. In this way, the support plate 16 is fixed by the pair of level adjustment bolts 18 and the lock nuts 22.

Next, the seating plates 20 of the pair of level adjustment bolts 18 are seated on the support surface of the concrete skeleton F via the cushion rubber 21. At this time, the level adjustment bolts 18 are not fixed onto the support surface of the concrete skeleton or the vertical inverted small beams 6T.
Therefore, the pair of level adjustment bolts 18 can move freely laterally relative to the support surface of the concrete structure F, and a gap is formed between the bottom surface of the support plate 16 and the concrete structure F, so that the bottom surface does not come into contact with the concrete structure F.
Anti-vibration rubber 17 is tightly fitted into the recess of the support plate 16 without being fixed thereto. The lower surface of the joist 10 is supported on this anti-vibration rubber 17 without being fixed thereto.
Therefore, the support plate 16, the pair of level adjustment bolts 18, the pair of lock nuts 22 and the vibration-isolating rubber 17 that make up the adjustable under-floor support bracket FS are not fixed to each other and can be freely separated.

A number of joists 11 are placed on the joists 10, perpendicular to the longitudinal direction of the joists 10. When these joists 11 are made of wood, i.e., joists, they are fixed to the joists 10 by driving screws into the joists. Floorboards 12 are laid on the joists 11.

Therefore, in order to adjust the level of the floor surface of the floorboards 12 when the floorboards 12 are supported via the joists 11, the slats 10 and the adjustable under-floor support brackets FS, first, a pair of lock nuts 22 of each adjustable under-floor support bracket FS are rotated in the loosening direction using a tool such as a wrench Sp to move them away from the undersides of the left and right protrusions 16a of the support plate 16.
5 and 6, by rotating the hexagonal heads 18b at the lower ends of the pair of level adjustment bolts 18 to the left or right with a tool such as a wrench Sp, the left and right overhangs 16a of the support plate 16 screwed into the pair of level adjustment bolts 18 can be individually adjusted in height. Also, the vertical movement of the joists 10 supported on the support plate 16 can be individually adjusted. Furthermore, the level of the floor surface of the floor plate 12 supported on the multiple joists 10 can be adjusted. Also, the inclination of the floor plate 12 can be corrected.
After completing the level adjustment of the floor surface of the floor plate 12, the pair of lock nuts 22 can be screwed in to fix the floor plate 12 at a desired level position.

According to this embodiment, as shown in FIG. 5, the pair of level adjustment bolts 18 and lock nuts 22 can be rotated by an operator who descends into the underfloor space Hd using a tool such as a wrench Sp, without removing the floor panel 12.
This eliminates the need to remove the floor boards 12, which has been conventionally done, and facilitates the level adjustment work of the floor surface of the floor boards 12.
In particular, in a building equipped with a concrete structure F having an inverted beam structure as in this embodiment, the height of the underfloor space Hd can be made high, for example, 430 mm or more (649 mm: approximately 60 cm where there is no joist 10), which provides a large working space and makes level adjustment work even easier.

As shown in Figure 8, each component of the adjustable underfloor support bracket FS can be separated from the joists 10 and the support surface of the concrete structure F. This means that the joists 10, which have a long service life, can be left in place while the components of the adjustable underfloor support bracket FS, which have a shorter service life, such as the anti-vibration rubber 17 and the level adjustment bolts 18, can be replaced. This can also contribute to cost reduction and resource conservation when renovating a building.

Next, a method for adjusting the floor level of a building to restore the floor level that has dropped due to deterioration of the floor structure over time, an earthquake, or the like will be specifically described with reference to Figs.
Fig. 9 is a diagram showing how a worker crawls into the underfloor space of an apartment building to restore the floor level. Fig. 10 is a diagram showing how a jack is placed between the underside of the joists in the underfloor space and the top surface of the slab. Fig. 11 is a diagram showing how the joists are jacked up by the hydraulic jack in Fig. 10. Fig. 12 is a diagram showing how the level of the floor structure, which has been lifted by jacking up the joists in Fig. 11, is being adjusted so that the load is no longer applied.

Although the floor structure Fr is supported by floor adjuster-type under-floor support fittings FS, the entire floor weighs several hundred kg because numerous joists 10 are stretched throughout the structure.
For this reason, it is practically difficult for a worker to crawl into the under-floor space Hd and use a wrench Sp to rotate the level adjustment bolt 18 and lock nut 22 of the adjustable under-floor support bracket FS to move the entire floor structure Fr upward.

Therefore, in this embodiment, the floor level of the building is adjusted by the following procedure (first to third steps).
Here, the building has a plurality of vertical inverted beams such as 5L protruding at intervals from the upper surface of the floor slab Sf, a plurality of joists 10 supported between the opposing inverted beams, and floorboards 12 laid on the joists 10 via joists 11, thereby forming one or more underfloor spaces Hd surrounded by a plurality of vertical inverted beams 5L.

The adjustment method of the embodiment is a method for adjusting the floor level of a building when the floor level of the building drops by N mm after construction.
The conditions under which this adjustment method can be applied are shown below.
First, both ends of the joists 10 are supported by adjustable underfloor support brackets FS, the vertical position of which can be adjusted within a range of, for example, ±12.5 mm (±M mm (M is a value equal to or greater than N)).
Another point is that the underfloor space Hd has a height H necessary for a worker to place a hydraulic jack Uj on the underside of the slat 10 and on the top surface of the floor slab Sf and perform jacking up work. Specifically, the height H of the underfloor space Hd needs to be, for example, 430 mm or more. In this example, the height H of the underfloor space Hd is set to 430 mm, and the part above the underfloor space Hd (to the floor surface) is 219 mm, so the distance from the floor surface to the top surface of the slab Sf is 430 + 219 = 649 mm, and a certain amount of work space can be secured by avoiding the position where the slat 10 is crossing.

Under such conditions, in the first step, as shown in FIG. 9, an operator enters the underfloor space Hd.
Specifically, the worker enters the underfloor space Hd and places a wooden spacer Kb (spacer) between the underside of the joist 10 and the upper surface of the floor slab Sf at the end of the joist 10 in the sunken area (at a position near the adjustable underfloor support bracket FS of the horizontal inverted girder 5T). The wooden spacer Kb is, for example, 90 mm x 90 mm x 200 mm, stacked in two layers to create a base 180 mm high.

Next, in the second step, the worker places a hydraulic jack Uj between the underside of the joist 10 to be adjusted and the upper surface of the floor slab Sf, and jacks up the joist 10 with the hydraulic jack Uj, moving the joist 10 upward by approximately N mm.
Specifically, the worker sets a hydraulic jack Uj (height approximately 250 mm) on a base made of a wooden slat corner Kb so that it is inserted directly below the joists 10, as shown in FIG.
In addition, since the approximate weight of one joist 10 is about 160 kg, a small manual hydraulic jack Uj of about 2 tonnes is used.
Here, the worker operates the hydraulic jack Uj in the direction of the arrow, lightly applies hydraulic pressure, and adjusts the position so that the upper part of the stroke is at the center of the width of the joists 10.

Then, as shown in Fig. 11, the worker operates the handle of the hydraulic jack Uj to jack up the spur 10, thereby moving the spur 10 upward by approximately N mm and separating (floating) the spur 10 from the floor adjuster-type underfloor support fittings FS. Approximately N mm is the height at which the lowered floor level is restored to its original height.
Specifically, the handle of the hydraulic jack Uj is moved up and down (in the direction of the arrow in FIG. 10) to extend the stroke, thereby jacking up the vehicle.

When jacking up the building, in order to prevent the level being raised too high and damaging the interior baseboard, another worker is stationed on the raised floor to observe, and the worker below the floor will work in unison. The workers may wear wireless devices, such as headsets, and exchange information with each other via the wireless devices. The worker above the floor may also take pictures of the interior baseboard with a camera, and the worker below the floor may perform the jacking up work while watching the camera image on a monitor.

In the third step, the worker adjusts the adjustable under-floor support bracket FS by approximately +Nmm, and raises the floor surface level by Nmm by supporting the joist 10 to be adjusted, which has moved upward by approximately Nmm, with the adjustable under-floor support bracket FS.
Specifically, if the worker has been able to jack up the joists 10 to the appropriate level through the jacking up operation, there will be no load due to the weight of the joists 10 on the adjustable under-floor support bracket FS, so as shown in Figure 12, he or she will use a wrench Sp to rotate and loosen the lock nut 22 of the adjustable under-floor support bracket FS shown in Figures 5 and 6, and then use the wrench Sp to rotate the hexagonal head 18b (including the seat plate 20) at the lower end of the level adjustment bolt 18 until the support plate 16 with the vibration-isolating rubber 17 in Figures 7 and 8 reaches the appropriate level, thereby adjusting the position of the support plate 16 upward by approximately +Nmm.

Through this adjustment, the joists 10 to be adjusted, which have moved upward by approximately N mm, are supported by the adjustable under-floor support bracket FS, and are fixed in a state in which the floor surface level has been raised by N mm.
Specifically, after the support plate 16 with the anti-vibration rubber 17 is set in the appropriate position, the worker tightens the lock nut 22 with the wrench Sp to fix the support plate 16 in place.
Then, after the worker confirms with another worker on the double floor that the floor level has been restored to its original position, the worker removes the hydraulic jack Uj and wooden flap corners Kb and cleans up the area.

According to the method for adjusting the floor level of a building in this embodiment, an operator jacks up the joists 10 with a hydraulic jack Uj (lifts them off the adjustable underfloor support bracket FS), and then adjusts the floor level by rotating the hexagonal head 18b and lock nut 22 at the lower end of the level adjustment bolt 18 of the adjustable underfloor support bracket FS, which is no longer carrying the load of the joists 10, with a wrench Sp.
This makes it possible to restore the floor level that has dropped due to deterioration of the floor structure Fr over time, an earthquake, or the like, simply by using the human force of a worker who enters the underfloor space Hd.

In this way, according to the method for adjusting the floor level of a building in this embodiment, a worker who crawls under the floor jacks up the sills 10 and then adjusts the adjustable underfloor support brackets FS, which have an adjustment margin, making it easy to manually restore the floor level that has dropped due to deterioration of the floor structure Fr over time or due to an earthquake, etc.

Next, other jacking up methods (methods for adjusting the floor level of other buildings) will be explained.
The subsidence phenomenon that may occur in the double floor structure of the Lunes method does not necessarily occur in only one of the multiple joists 10 arranged in the underfloor space Hd of 600 mm below the floor. It is also possible that level adjustment will be required for the multiple joists 10 or the entire joist 10.

In such a case, clamping hydraulic jacks Uj to the bottom of all the joists 10 placed in the underfloor space Hd and adjusting the levels while jacking up each joist 10 one by one is a labor-intensive task, and it is difficult to precisely adjust the parallelism of the floor surface.

Therefore, another adjustment method will be described with reference to FIGS.
Fig. 13 is a side view of a jig used in another example of the method for adjusting the floor level of a building according to the present invention, which is placed in the underfloor space. Fig. 14 is a cross-sectional view taken along the line A-A in Fig. 13. Fig. 15 is a diagram showing an example of a joint metal fitting used together with the jig shown in Fig. 13.

In this adjustment method, as shown in Figures 13 and 14, a 3,000 mm long jig G is used that is made of the same material as the joists 10 (a beam material made by bending a 2.3 mm thick galvanized steel plate into a Σ-shaped cross section), and a joint fitting Jk is inserted between the joists 10 and the hydraulic jack Uj.
The jig G is placed below the joists 10 so as to intersect, for example perpendicular to, the multiple joists 10 to be adjusted.

The joint fitting Jk is intended to accommodate various spacings between the joists 10 and is inserted between the joists 10 and the jig G.
Specifically, as shown in FIG. 15, the joint fitting Jk is formed by placing two fittings K1, K2, each of which has a U-shaped cross section, facing each other above and below with their backs to each other and fixing them to each other by welding or the like in an orientation rotated 90 degrees around the center of the opposing faces as an axis.

Rubber members Gm for fastening are placed on all sides of the main support of the metal fitting K1. The width of the main support 10 is 50 mm, so the thickness of the rubber members Gm is set to 1 mm, and the distance (width) between the sides of the main support of the metal fitting K1 is set to 52 mm, so that the main support 10 fits snugly into the main support of the metal fitting K1.

In this case, the worker first places wooden flap corners Kb at each of the two positions where the jig G will be passed, and then places the hydraulic jack Uj on top of them.
Next, the joint fittings Jk are arranged on the jig G in a number equal to the number of the joists 10 to be adjusted.

Next, the worker positions the jig G so that it spans under multiple stilts 10. Then, while placing it on two hydraulic jacks Uj, the worker slides each joint fitting Jk on the jig G to the position of each stilt 10 and places it against the stilt 10.

Then, the worker loosens the lock nuts 22 (see Figures 7 and 8) of the adjustable underfloor support brackets FS at both ends of each spur 10, and then operates the two hydraulic jacks Uj to jack up the multiple spurs 10 together with the jig G at one go.

After jacking up, the adjustable underfloor support fittings FS at the ends of each joist 10 are adjusted and the support plate 16 is raised to the height of the joist 10 and fixed in the restored position.
Thereafter, the stroke of the hydraulic jack Uj is lowered, and the hydraulic jack Uj and the wooden flap angle Kb are removed.

In this way, according to the floor level adjustment method of this example, joint fittings Jk and jigs G are placed under multiple joists 10, and hydraulic jacks Uj placed in two places under the jigs G raise the multiple joists 10 together with the jigs G in one go, which significantly reduces the amount of work required and allows the parallelism of the floor surface to be precisely adjusted.

Although one embodiment of the present invention has been described above, the present invention is not limited to the above-mentioned embodiment, and modifications, improvements, etc. that can achieve the object of the present invention are considered to be included in the present invention.

For example, in the above embodiment, a single joist 10 (a beam material made by bending a 2.3 mm thick steel plate into a Σ-shaped cross section) is used to support the bridge between two opposing beams, but it is also possible to use a double beam with two joists 10 facing each other with their backs facing each other to increase strength.

For example, in the above embodiment, a joist 10 with a Σ-shaped cross section is exemplified, but other types of beams such as C-beams with a U-shaped cross section and H-beams with an H-shaped cross section may also be used, and the shape of the beams is not limited.

For example, in the above embodiment, the hydraulic jack Uj was placed on a wooden flaps Kb as a base in the underfloor space Hd to jack it up, but the equipment used for jacking up should be a hydraulic jack Uj with performance according to the weight of the floor structure Fr, and the number and shape of the bases should be selected according to the height of the underfloor space Hd and the hydraulic jack Uj.

In summary, the method for adjusting floor level of a building to which the present invention is applied is sufficient as long as it has the following steps, and can take various forms.
That is, the method for adjusting the floor level of a building to which the present invention is applied is as follows:
A method for adjusting the floor level of a building when the floor level after construction is lowered by N mm in a building in which a plurality of inverted beams (e.g., vertical inverted small beams 6L in FIG. 2, vertical inverted large beams 5L in FIG. 10, etc.) are provided on the upper surface of a slab (e.g., floor slab Sf in FIG. 2, etc.) at intervals, a plurality of joists (e.g., joists 10 in FIG. 10, etc.) are supported between the opposing inverted beams, and flooring materials (e.g., floor boards 12 in FIG. 10, etc.) are laid on the joists (e.g., joists 11 in FIG. 10, etc.) via joists, thereby forming one or more underfloor spaces (e.g., underfloor space Hd in FIG. 10, etc.) surrounded by a plurality of inverted beams,
Both ends of the joist (e.g., joist 10 in FIG. 10 ) are supported by an adjustable underfloor support (e.g., adjustable underfloor support bracket FS in FIG. 10 ) that can adjust the vertical position within a range of ±M mm (M is a value equal to or greater than N),
The underfloor space (e.g., underfloor space Hd in FIG. 10 ) has a height (e.g., height H in FIG. 10 ) necessary for an operator to perform jacking up work by placing a jack (e.g., hydraulic jack Uj in FIG. 10 ) on the underside of the joists (e.g., joists 10 in FIG. 10 ) and the upper surface of the slab (e.g., floor slab Sf in FIG. 10 ),
A first step in which the worker enters the underfloor space (for example, the underfloor space Hd in FIG. 10 );
A second step in which the worker places a jack (e.g., hydraulic jack Uj in FIG. 10 ) between the underside of the joist to be adjusted (e.g., joist 10 in FIG. 10 ) and the upper surface of the slab (e.g., floor slab Sf in FIG. 10 ), and jacks up the jack (e.g., hydraulic jack Uj in FIG. 10 ), thereby moving the joist to be adjusted (e.g., joist 10 in FIG. 10 ) upward by approximately N mm;
A third step in which the worker adjusts the adjustable underfloor support (e.g., the adjustable underfloor support bracket FS in FIG. 10 ) by approximately +Nmm, and supports the joist to be adjusted (e.g., the joist 10 in FIG. 10 ) that has moved upward by approximately Nmm with the adjustable underfloor support (e.g., the adjustable underfloor support bracket FS in FIG. 10 ), thereby raising the floor surface level by Nmm;
including.
In this way, by jacking up the joists (such as joists 10 in Figure 2) and adjusting the adjustable underfloor support fixtures (such as adjustable underfloor support fittings FS in Figure 10) that have adjustment room, the floor level that has dropped due to deterioration over time of the floor structure (such as floor structure Fr in Figure 2) can be restored by manual work.

The adjustable-type under-floor support device (such as the adjustable-type under-floor support bracket FS in Figure 10) has a pair of level adjustment bolts (such as the level adjustment bolts 18 in Figures 7 and 8) and a lock nut (such as the lock nut 22 in Figures 7 and 8) for adjustment.
The adjustment allowance M of the adjustable underfloor support (for example, the adjustable underfloor support bracket FS in FIG. 10) is ±12.5 mm.
The height (for example, the height arrow H in FIG. 10) of the underfloor space (for example, the underfloor space Hd in FIG. 10) is 430 mm or more.

10: joist, 16: support plate, 16a: extension, 16b: female thread hole, 17: vibration-proof rubber, 18: level adjustment bolt, 18a: male thread, 18b: head, 20: seat plate, 22: lock nut, F: concrete body, Fr: floor structure, FS: adjustable underfloor support bracket, G: jig, Hd: underfloor space, Jk: joint bracket, Kb: wooden flaps, Sf: floor slab, Sp: spanner, Uj: hydraulic jack

Claims (4)

A method for adjusting the floor level of a building when the floor level after construction is lowered by N mm in a building in which a plurality of inverted beams are protruding from the upper surface of the slab at intervals, a plurality of joists are supported between the opposing inverted beams, and flooring is laid on the joists via floor joists to form one or more underfloor spaces surrounded by the plurality of inverted beams,
Both ends of the joists are supported by adjustable underfloor supports whose vertical positions can be adjusted within a range of ±M mm (M is a value equal to or greater than N);
When the underfloor space has a height necessary for a worker to place a jack on the underside of the joist and the top surface of the slab and perform jacking up work,
A first step in which the worker enters the underfloor space;
A second step in which the worker places a jack between the lower surface of the joist to be adjusted and the upper surface of the slab, and jacks up the joist to be adjusted by approximately N mm in the upward direction;
A third step in which the worker adjusts the adjustable underfloor support by approximately +Nmm to support the joist to be adjusted that has moved upward by approximately Nmm with the adjustable underfloor support, thereby raising the floor surface level by Nmm;
A method for adjusting floor levels in a building, including: The adjustable under-floor support has a pair of level adjustment bolts and lock nuts for adjustment.
The method for adjusting floor levels of a building according to claim 1. The adjustment margin M of the adjuster-type under-floor support is ±12.5 mm.
The method for adjusting floor levels of a building according to claim 1. The height of the underfloor space is 430 mm or more.
The method for adjusting floor levels of a building according to claim 1.

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