JP7472249B2 - Anti-vibration floating floor support spring extension mechanism and anti-vibration floating floor construction method - Google Patents

Description

The present invention relates to an anti-vibration floating floor support spring extension mechanism and an anti-vibration floating floor construction method.

In the past, there have been cases where vibrations caused by excitation forces on the floor have been transmitted through the ground to the surrounding area, resulting in vibration problems. In live music venues, concert halls, dance studios, etc., there have been cases where vibrations caused by so-called vertical movement, where many people move in time with the music, have caused surrounding buildings to shake, resulting in problems.

As a countermeasure against such vibration problems, there is a method of designing a floor made of RC slabs as a floating floor that is insulated from the structural frame to suppress vibration propagation (see Patent Document 1 below). The structure of such a vibration-proof floating floor is shown in Figure 34. The structural frame is partially recessed, and a floating floor supported by springs is provided. The floating floor needs to be displaced vertically relative to the structural frame, and the displacement of the support springs corresponds to this. In order to increase the vibration-proof effect, the stiffness of the support springs should be reduced and the floor should be supported more softly. However, if the stiffness of the support springs is too small, problems may occur in the usability of the floor, such as excessive sinking due to the load on top and discomfort caused by the floor moving when walking. Therefore, the vertical natural frequency of the floating floor is generally set to about 1 Hz or more, and the characteristics of the support springs are set so that the vertical displacement during normal use is about 20 mm or less.

Air springs, coned disc springs, and coil springs are used as support springs for floating floors like the one described above. However, air springs are expensive and require mechanical equipment such as compressors, so coned disc springs and coil springs are often used in buildings. Such spring members are generally expected to deform only in the axial direction (support force direction), and there is a risk that the specified performance will not be achieved if deformation occurs in a direction perpendicular to the axis. For this reason, as shown in Figure 34, a gap is provided between the floating floor and the structure to insulate them, allowing the floating floor to smoothly move vertically relative to the structural frame. Also, in order to prevent the support springs from being displaced in directions other than the support force direction, horizontal restraint materials to restrain the horizontal displacement of the floating floor may be provided between the floating floor and the structural frame.

JP 2013-53720 A

However, it is difficult to prevent the floating floor from moving horizontally during construction. If the floating floor concrete is poured while supported by the support springs, the work involved in pouring the concrete or the drying shrinkage of the concrete may cause horizontal displacement of the support springs, which may adversely affect the performance of the springs. To prevent this, it is preferable to support the load not with the support springs but with temporary support members such as shoring when pouring the floating floor concrete, and then transfer the load to the support springs after the floating floor concrete has hardened. To perform such load transfer work, it is necessary to expand and contract the support springs at the installation position.
Furthermore, in the unlikely event that the support springs are damaged by the application of unexpected external forces such as a major earthquake, the support springs will need to be replaced. In order to replace the support springs, temporary support members such as shoring must be installed to temporarily support the floating floor's own weight, the damaged support springs must then be compressed and removed, and new support springs must be installed in the designated position, after which the load must be transferred to the new support springs, which also requires the support springs to be expanded and contracted at the installed position.

The present invention has been made in consideration of the above circumstances, and provides an anti-vibration floating floor support spring extension mechanism that allows the support spring to be extended or contracted at the installation position during construction and replacement, and a construction method for an anti-vibration floating floor.

In order to achieve the above object, the present invention employs the following means.
In other words, the vibration-proof floating floor support spring extension mechanism of the present invention is a vibration-proof floating floor support spring extension mechanism used when installing a floating floor above a foundation, and comprises a first spring unit having a lower body installed on the foundation, an upper body arranged above the lower body and on which the floating floor is installed, a lower plate fixed to the lower body, an upper plate arranged below the upper body so as to be able to support the upper body, and a support spring arranged between the lower plate and the upper plate, a first jack set fixed to the lower body or the lower plate and capable of applying a downward force to the upper plate, and a first temporary support member capable of supporting the floating floor, and the first jack set comprises a reaction support structure fixed to the lower body or the lower plate, a first steel rod connected to the upper plate, a first jack capable of applying a downward force to the first steel rod, and a position holding member capable of fixing and releasing the first steel rod to any position of the reaction support structure.

In the vibration-proof floating floor support spring extension mechanism configured in this manner, when constructing the floating floor, a downward force is applied to the upper plate of the first spring unit by the first jack set to shorten the overall length of the first spring unit. When constructing the floating floor, the floating floor is supported by a first temporary support member such as a shoring. After at least a portion of the floating floor is completed (for example, the first layer of concrete has hardened), the downward force is removed from the first spring unit by the first jack set, the overall length of the first spring unit is lengthened, and the floating floor is supported by the first spring unit. Therefore, in the initial stage of construction of the floating floor, it is the first temporary support member such as a shoring that supports the floating floor's own weight, and the first spring unit is insulated from the floating floor, so that external forces caused by construction work are prevented from acting on the first spring unit.

In addition, in the vibration-proof floating floor support spring extension mechanism configured in this manner, when the first jack of the first jack set is loaded with the upper plate not connected to the upper body, the first steel rod is pulled downward and moves downward relative to the reaction support frame. A downward force is applied to the upper plate of the first spring unit connected to the first steel rod, so the overall length of the first spring unit is shortened. In this state, when the first steel rod is fixed in its current position to the reaction support frame by the position retaining member, the short overall length of the first spring unit is maintained. In this state, the first jack of the first jack set can be unloaded and removed. In this state, a tensile force is generated in the first steel rod between the connection part with the upper plate and the position retaining member.
Furthermore, from this state, the first jack is installed and a force greater than the load when the first spring unit is compressed is applied to apply a tensile force to the entire first steel rod. After that, the position retaining member that secures the first steel rod to the reaction support structure is released and the first jack is unloaded. This removes the downward force that was acting on the first spring unit, and the overall length of the first spring unit becomes longer.
In this way, by using the support spring expansion and contraction mechanism, the installed dimensions of the first spring unit can be reduced while the length can be easily adjusted.

The vibration-isolating floating floor construction method according to the present invention is characterized by comprising a spring unit installation step of installing a first spring unit on a lower body, a jack set installation step of installing a first jack set on the lower body and connecting a first steel rod of the first jack set to the upper plate of the first spring unit, a first temporary support member installation step of installing a first temporary support member capable of supporting a floating floor, an upper body installation step of installing an upper body above the first spring unit and the first jack set, a downward force application step of applying a downward force from the first jack set to the upper plate of the first spring unit, a floating floor construction step of constructing the floating floor above the upper body and supporting the floating floor with the first temporary support member, and a load transfer step of removing the downward force applied to the upper plate and supporting the floating floor with the first spring unit.

In the vibration-isolation floating floor construction method configured in this manner, in the downward force application process, a downward force is applied to the upper plate of the first spring unit by the first jack set. This shortens the overall length of the first spring unit. In the floating floor construction process, the floating floor's own weight is supported by the first temporary support member. After at least a portion of the floating floor is completed (for example, the first layer of concrete has hardened), the downward force applied to the upper plate in the load transfer process is removed. This causes the first spring unit to expand and support the floating floor. Therefore, in the initial stage of floating floor construction, it is the first temporary support member such as a shoring that supports the floating floor's own weight, and the first spring unit is insulated from the floating floor, so it is possible to prevent external forces caused by construction work from acting on the first spring unit and adversely affecting the performance of the first spring unit.

The anti-vibration floating floor support spring extension mechanism and the anti-vibration floating floor construction method of the present invention can prevent external forces caused by construction work from acting on the spring unit during construction, which can adversely affect the performance of the spring unit.

1 is a diagram showing the basic configuration of a disc spring unit of an anti-vibration floating floor support spring extension mechanism according to one embodiment of the present invention. FIG. 1A and 1B are conceptual diagrams of the expansion and contraction of a disc spring unit of an anti-vibration floating floor support spring expansion mechanism according to one embodiment of the present invention, in which (a) shows the time of loading without preload, (b) shows the time of supporting the floor's own weight without preload, (c) shows the time of loading with preload, and (d) shows the time of supporting the floor's own weight with preload. 1 is a graph showing the range of motion of a disc spring unit in relation to the load and displacement of the disc spring of an anti-vibration floating floor support spring extension mechanism according to one embodiment of the present invention. In an anti-vibration floating floor support spring extension mechanism according to one embodiment of the present invention, (a) is an elevational view showing the configuration of a spring unit and a jack set, and (b) is a plan view showing the configuration of the spring unit and the jack set. In an anti-vibration floating floor support spring extension mechanism relating to a variant 1 of one embodiment of the present invention, (a) is an elevational view showing the configuration of a spring unit and a jack set, and (b) is a plan view showing the configuration of the spring unit and the jack set. 1A and 1B are front and plan views showing an example of installation of a temporary support member in an anti-vibration floating floor support spring extension mechanism relating to a variant 1 of one embodiment of the present invention. A diagram showing a construction method of an anti-vibration floating floor support spring extension mechanism relating to variant 1 of one embodiment of the present invention. This is a diagram showing a construction method for an anti-vibration floating floor support spring extension mechanism relating to variant 1 of one embodiment of the present invention, and shows a process subsequent to the process shown in Figure 7. This is a diagram showing a construction method for the vibration-isolating floating floor support spring extension mechanism relating to variant 1 of one embodiment of the present invention, and shows a process subsequent to the process shown in Figure 8. This is a diagram showing a construction method for an anti-vibration floating floor support spring extension mechanism relating to variant 1 of one embodiment of the present invention, and shows a process subsequent to the process shown in Figure 9. This is a diagram showing a construction method for an anti-vibration floating floor support spring extension mechanism relating to variant 1 of one embodiment of the present invention, and shows a process subsequent to the process shown in Figure 10. This is a diagram showing a construction method for an anti-vibration floating floor support spring extension mechanism relating to variant 1 of one embodiment of the present invention, and shows a process subsequent to the process shown in Figure 11. This is a diagram showing a construction method for an anti-vibration floating floor support spring extension mechanism relating to variant 1 of one embodiment of the present invention, and shows a process subsequent to the process shown in Figure 12. This is a diagram showing a construction method for an anti-vibration floating floor support spring extension mechanism relating to variant 1 of one embodiment of the present invention, and shows a process subsequent to the process shown in Figure 13. This is a diagram showing a construction method for an anti-vibration floating floor support spring extension mechanism relating to variant 1 of one embodiment of the present invention, and shows a process subsequent to the process shown in Figure 14. This is a diagram showing a construction method for an anti-vibration floating floor support spring extension mechanism relating to variant 1 of one embodiment of the present invention, and shows a process subsequent to the process shown in Figure 15. This is a diagram showing a construction method for an anti-vibration floating floor support spring extension mechanism relating to variant 1 of one embodiment of the present invention, and shows a process subsequent to the process shown in Figure 16. A plan view showing the configuration of the lower body and lower plate of the vibration-proof floating floor support spring expansion mechanism related to variant 2 of one embodiment of the present invention. This is an elevational view of the vibration-proof floating floor support spring extension mechanism related to variant 2 of one embodiment of the present invention, viewed from direction A in Figure 18. This is an elevational view of the vibration-proof floating floor support spring extension mechanism related to variant 2 of one embodiment of the present invention, viewed from direction B in Figure 18. A plan view showing the configuration of the upper plate of the vibration-proof floating floor support spring expansion mechanism related to variant 2 of one embodiment of the present invention. A plan view showing the configuration of the intermediate plate of the vibration-proof floating floor support spring expansion mechanism related to variant 2 of one embodiment of the present invention. This is an elevational view showing the installation state of an existing spring unit in a method for replacing a spring unit of an anti-vibration floating floor in accordance with variant 2 of one embodiment of the present invention. This is an elevational view showing the existing jack set installation process of the method for replacing a spring unit of an anti-vibration floating floor in accordance with variant 2 of one embodiment of the present invention. This is an elevational view showing the state immediately before the existing spring unit contraction process in the method for replacing a spring unit of an anti-vibration floating floor in accordance with variant 2 of one embodiment of the present invention. This is an elevational view showing the existing spring unit contraction process of the method for replacing a spring unit of an anti-vibration floating floor in accordance with variant 2 of one embodiment of the present invention. This is an elevational view showing the existing spring unit contraction retention process of the method for replacing a spring unit of an anti-vibration floating floor in accordance with variant 2 of one embodiment of the present invention. This is an elevational view showing the process of removing an existing spring unit in the method of replacing a spring unit of a vibration-isolation floating floor in accordance with variant 2 of one embodiment of the present invention. This is an elevational view showing the new spring unit installation process of the method for replacing a spring unit of an anti-vibration floating floor in accordance with variant 2 of one embodiment of the present invention. This is an elevational view showing the new jack installation process in the method for replacing a spring unit of an anti-vibration floating floor in accordance with variant 2 of one embodiment of the present invention. This is an elevational view showing the steel bar removal process in the method for replacing a spring unit of a vibration-isolation floating floor in accordance with variant 2 of one embodiment of the present invention. This is an elevational view showing the new spring unit extension process of the method for replacing a spring unit of an anti-vibration floating floor in accordance with variant 2 of one embodiment of the present invention. This is an elevational view showing the new spring unit fixing process in the method for replacing a spring unit of an anti-vibration floating floor in accordance with variant 2 of one embodiment of the present invention. FIG. 1 is a diagram showing the configuration of a conventional vibration-isolating floating floor.

The vibration-isolating floating floor support spring expansion mechanism and the vibration-isolating floating floor construction method of the present invention will be described.
First, we will explain the support spring (spring unit 2) used in the vibration-isolating floating floor support spring expansion mechanism of the present invention, and the difference in sinking of the support spring depending on whether or not there is a preload.

To ensure the rigidity and vertical stroke required for an anti-vibration floating floor, the length of the support springs becomes quite long, making them difficult to handle when transporting, installing, and replacing. Furthermore, construction is extremely difficult if the springs continually shrink when the floating floor concrete is poured. For example, consider a 1 Hz floating floor on an RC floor with a floor area of 600 m2 (thickness of 1 m).

If the floor weight is 2.4 t/m ³ × 600 m ² × 1 m = 1,440 t, the floating floor natural vibration is 1 Hz, and the support spring rigidity is 57 kN/mm, then the required vertical displacement of the support spring is 270 mm or more, as shown in the following formula (1).

FIG. 1 is a diagram showing a basic structure of a disc spring unit.
The support spring is assumed to be a disc spring unit 110 as shown in Fig. 1. As shown in Fig. 1, the disc spring unit 110 mainly includes a lower plate 101, an upper plate 102, upper and lower seat plates 103 and 104, a plurality of disc springs 105, and a guide 106.

The disc spring unit 110 can be configured with any desired characteristics depending on its shape and combination. Figure 1 shows a combination of multiple disc springs 105 of any shape to obtain a desired stiffness and stroke.

FIG. 2 is a conceptual diagram of the expansion and contraction of the disc spring unit 110, where (a) shows the time of loading without preload, (b) shows the time of supporting the floor's own weight without preload, (c) shows the time of loading with preload, and (d) shows the time of supporting the floor's own weight with preload.
As shown in FIG. 2, the length of the overlapping disc springs is approximately 1,000 mm.

As shown in Figures 2(a) and (b), when there is no preload, the entire required vertical displacement must be set as the range of motion (set at 290 mm), so the overall length of the disc spring unit 110 is long when delivered, and the amount of sinking due to the floor's own weight during installation is large.

On the other hand, Figures 2(c) and (d) show the case where a load equivalent to 70% (174 mm) of the sinking amount due to the floor's own weight is applied as a preload during manufacturing at the factory, and the length of the spring is shortened to the specified dimension. In this case, the range of motion is kept small (set to 120 mm in Figure 2) because it is sufficient to have a total of 96 mm or more, consisting of the remaining 30% (74 mm) of the floor's own weight, the weight of the spectators, and the dynamic displacement. This shortens the overall length of the disc spring unit 110 when it is brought in, making transportation and moving easier. In addition, because the spring does not displace vertically until the amount of concrete poured exceeds 70%, the variation in the amount of sinking due to the spring is small, making construction easier.

The amount of preload to be introduced is determined taking into consideration the vertical range of motion required when using a floating floor and the construction method.
FIG. 3 is a graph showing the range of motion of the disc spring unit 110 in relation to the load and displacement of the disc spring of the support spring expansion/contraction mechanism according to one embodiment of the present invention.
As shown in Figure 3, the necessary vertical movement range is determined by considering sinking due to the weight of spectators (static displacement), displacement due to vertical vibration (dynamic displacement), and, if necessary, the amount of displacement during an earthquake. The preload setting value is determined within the preload setting range that can secure that vertical movement range, taking into account the method of pouring the floating floor concrete, etc.

Next, the vibration-isolating floating floor support spring expansion/contraction mechanism will be described.
4A is an elevation view showing the configuration of the spring unit and the jack set in the vibration-proof floating floor support spring extension mechanism, and FIG. 4B is a plan view showing the configuration of the spring unit and the jack set. FIG. 4 shows the state in which the jack is unloaded and the disc spring is extended after the first layer concrete described later has hardened, and the disc spring unit is supported by the load.
The vibration-isolating floating floor support spring extension mechanism is a mechanism for adjusting the length of the support springs used when temporarily supporting the floating floor load on temporary support members such as shoring and then transferring the load to the support springs.

As shown in FIG. 4, the vibration-proof floating floor support spring extension mechanism 100 comprises a lower capital (lower body) 11 installed on a foundation mat (foundation) M, an upper capital (upper body) 12 on which the floating floor F is installed, and a spring unit (first spring unit) 2 and a jack set (first jack set) 3 arranged between the lower capital 11 and the upper capital 12.

As shown in FIG. 4(b), in plan view, the lower capital 11 and the upper capital 12 are larger than the spring unit 2 and the jack set 3. In this embodiment, in plan view, the lower capital 11 and the upper capital 12 are rectangular, but the shape can be set as appropriate.

The spring unit 2 has a lower plate 21, an upper plate 22, and a spring body (support spring) 23. In this embodiment, the spring body 23 is configured with multiple disc springs 23a arranged in the vertical direction. In this embodiment, the lower plate 21, the upper plate 22, and the disc springs 23a are circular in plan view, but the shape can be appropriately set to a rectangle or other shape.

The lower plate 21 is fixed to the lower capital 11 with an anchor bolt a1 or the like. The upper plate 22 is disposed below the upper capital 12. In the state shown in FIG. 4, the upper plate 22 is disposed in contact with the lower surface of the upper capital 12. The upper plate 22 can be fixed to the upper capital 12 with an upper fixing nut n1.

The jack set 3 has a reaction support structure 30, a PC steel bar (first steel bar) 41, and a center hole jack (first jack) 43. In this embodiment, the jack set 3 is set on both sides of the spring unit 2.

The reaction support structure 30 has a lower fixed plate 31, an upper fastening plate 32, and a support frame 33.

The lower fixing plate 31 is disposed adjacent to the lower plate 21 of the spring unit 2. The lower fixing plate 31 is fixed to the lower capital 11 with an anchor bolt a2 or the like. The upper fastening plate 32 is disposed above the lower fixing plate 31. The support frame 33 connects the lower fixing plate 31 and the upper fastening plate 32.

The PC steel rod 41 extends in the vertical direction. The upper end of the PC steel rod 41 is inserted into a through hole (not shown) formed in the upper plate 22 and fastened with an upper nut n11. An intermediate nut (position-retaining member) n12 is provided in the vertical middle of the PC steel rod 41. The intermediate nut n12 is provided below the upper fastening plate 32. A lower nut n13 is provided at the lower end of the PC steel rod 41 to secure the center hole jack 43 to the PC steel rod 41.

The center hole jack 43 is, for example, hydraulic, has a circular shape in a plan view, and has a through hole (not shown) that penetrates vertically through the center. A PC steel bar 41 is inserted through the through hole.

FIG. 5 shows a first modified example of the vibration-isolating floating floor support spring expansion mechanism.
Figure 5 is a cross-sectional view showing the configuration of a spring unit and a jack set in a vibration-proof floating floor support spring extension mechanism relating to variant 1 of one embodiment of the present invention, and (a) a plan view showing the configuration of the spring unit and the jack set.
As shown in Figure 5, in this modified example of the vibration-proof floating floor support spring extension mechanism 100A, the lower plate 21A of the spring unit (first spring unit) 2A is integrated with the lower fixed plate 31 of the jack set 3, and the support frame 33 of the jack set 3 is fixed to the lower plate 21A.

6A and 6B show an example of installation of a temporary support member in the first modified example of the vibration-isolating floating floor support spring extension mechanism, where (a) is a front view and (b) is a plan view.
As shown in Fig. 6, in the vibration-isolating floating floor support spring extension mechanism 100A, shoring (first temporary support members) 45, 46 are installed between the base mat M and the floating floor F, and between the lower capital 11 and the upper capital 12. The shoring 45 is installed on both sides of the lower capital 11 and the upper capital 12. The shoring 46 is installed at the four corners of the lower capital 11 and the upper capital 12, which are rectangular in plan view.

Next, a method for constructing the vibration-isolating floating floor F will be described with reference to Figures 7 to 17. In the following description of the construction method, a method using the vibration-isolating floating floor support spring expansion mechanism 100 will be described.
(Spring unit installation process)
7, the lower capital 11 is fixed to the base mat M. The lower plate 21 of the spring unit 2 is fixed to the lower capital 11 by an anchor bolt a1 (see FIG. 4(a)) or the like.

(Jack set installation process)
The reaction support structure 30 is installed on the lower capital 11. The lower fixing plate 31 (see FIG. 4(a)) of the reaction support structure 30 is fixed to the lower capital 11 with anchor bolts a2 (see FIG. 4(a)) or the like. The PC steel rod 41 is inserted into the through hole of the upper plate 22 of the spring unit 2 and fastened to the upper plate 22 with a nut n11. The center hole jack 43 is set on the PC steel rod 41. The lower nut n13 is fastened to the lower end of the PC steel rod 41 to fix the center hole jack 43 to the PC steel rod 41. The preload of the disc spring 23a (see FIG. 4; the same applies below) of the spring unit 2 is 296 kN.

(Temporary support member installation process)
As shown in Fig. 8, a support 45 is installed on the base mat M, and the length of the support 45 is adjusted to support the formwork F1. Also, a support 46 is installed on the lower capital 11, and the length of the support 46 is adjusted to support the upper capital 12.

(Upper capital (upper body) installation process)
The upper capital 12 is installed above the upper plate 22 of the spring unit 2 and the reaction support frame 30. The formwork F1 of the floating floor F is set on the upper capital 12.

(Downward force application process)
As shown in Fig. 9, the center hole jack 43 is loaded to pull the PC steel rod 41 downward. The upper end of the PC steel rod 41 is connected to the disc spring 23a of the spring unit 2 by the upper nut n11. This applies a downward force to the upper plate 22 of the spring unit 2.

As shown in Figure 10, the intermediate nut n12 is tightened up to the upper fastening plate 32 to hold the PC steel rod 41 in its current position on the reaction support structure 30. The center hole jack 43 is unloaded. A tensile force of 174 kN is generated in the PC steel rod 41 between the position of the upper nut n11 fastened to the upper plate 22 and the position of the intermediate nut n12 fastened to the upper fastening plate 32. The position of the lower nut n13 is marked on the PC steel rod 41 with a mark P (see Figure 11).

As shown in Figure 11, remove the lower nut n13 from the PC steel bar 41 and remove the center hole jack 43. The center hole jack 43 is temporarily placed in place as it will be used again in the subsequent process of extending the spring unit 2.

(Floating floor construction process)
As shown in Fig. 12, the first layer of concrete F11 is poured. Since the concrete is poured in multiple layers, only the first layer of concrete F11 is poured at this stage. In this state, the first layer of concrete F11 is supported by the shoring 45 and the shoring 46 that supports the upper capital 12.

The first layer of concrete is allowed to harden and dry and shrink. Horizontal vibration prevention devices (not shown) are installed around the perimeter of the floor.

As shown in Figure 13, set the center hole jack 43 on the PC steel bar 41 and tighten the lower nut n13 at the marked location.

(Load transfer process)
14, the center hole jack 43 is loaded to apply a load slightly larger than the load when the spring unit 2 is compressed. This generates a tensile force on the entire PC steel rod 41, making it possible to release the intermediate nut n12 of the PC steel rod 41. The intermediate nut n12 is loosened to a position where a gap of 30 mm is created between the upper fastening plate 32.

As shown in Figure 15, slowly unload the center hole jack 43 to stretch the disc spring 23a of the spring unit 2 so that the spring unit 2 supports the upper capital 12 and the concrete F11. The upper plate 22 of the spring unit 2 is fixed to the upper capital 12 with the upper fixing nut n1 (see Figure 4; the same applies below).

As shown in FIG. 16, remove the lower nut n13 from the PC steel bar 41 and remove the center hole jack 43. The center hole jack 43 is used to extend or contract other spring units 2.

17, the supports 45, 46 are removed, and the remaining concrete is poured in this state. Note that the reaction support structure 30 and the PC steel rods 41 may be left in place so that they can be used when replacing the spring unit 2.
In addition, the construction method when using the vibration-proof floating floor support spring extension mechanism 100A is the same as when using the vibration-proof floating floor support spring extension mechanism 100, except that the reaction support structure 30 is fixed in advance to the lower plate 21A of the spring unit 2, and the spring unit 2 and the jack set 3 are integrated, so they are also installed as a single unit.

When installing a large number of spring units 2 in the construction method of the vibration-isolating floating floor F described above, a reaction support structure 30 is required for each spring unit 2. However, since the center hole jack 43 can be used in turn by multiple reaction support structures 30, there is no need to prepare a center hole jack 43 for each spring unit 2.

During construction, horizontal external forces are applied to the load-bearing members due to the effects of concrete pouring and drying shrinkage of concrete, which is difficult to prevent. By transferring the load to spring unit 2 after the pouring of the first layer of concrete is completed and the drying shrinkage of the concrete is also complete, horizontal displacement of spring unit 2 can be prevented. The first layer of concrete is ensured to be thick enough to prevent the drying shrinkage of the second and third layers of concrete from affecting spring unit 2, and before pouring the second and third layers of concrete, the floating floor F is fixed with a temporary horizontal restraining jig to restrain horizontal movement.

In addition, the floating floor F is supported by many spring units 2, but since there is variation in the rigidity of the spring units 2 and the weight of the floating floor F, it is very difficult to adjust the floor top level by pouring concrete. Therefore, after all pouring is completed, if necessary, the spring units 2 are compressed using a jack set 3, and the height of the spring units 2 is adjusted by inserting filler, etc., to adjust the floor top level. This work can be performed at any time after the concrete pouring of the floating floor F has been completed.

Next, a method for replacing the spring unit 2 of the vibration-isolating floating floor F will be described.
An unexpected external force such as an earthquake may act on the spring unit 2 of the vibration-isolation floating floor F, causing damage to the spring unit 2, making it necessary to replace the damaged spring unit 2.
First, replacement of the spring unit 2 of the vibration-isolating floating floor support spring expansion mechanism 100 will be described.
As shown in FIG. 17, after the spring unit 2, the reaction support structure 30 and the PC steel rod 41 are installed, supports 45, 46 (see FIG. 6) are installed.

Replacement temporary fixtures 51, 52 (see FIG. 4; the same applies below) are installed on the upper plate 22 and lower plate 21 of the spring unit 2, respectively. The replacement temporary fixture 51 is installed so as to extend downward from the upper plate 22. The replacement temporary fixture 52 is installed so as to extend upward from the lower plate 21. At this stage, it is not necessary to connect the replacement temporary fixtures 51, 52 to each other. Flat steel, for example, can be used as the replacement temporary fixtures 51, 52.

Next, as shown in Figure 9, set the center hole jack 43 on the PC steel bar 41 and remove the upper fixing nut n1 (see Figure 4). Load the center hole jack 43 to pull the PC steel bar 41 downward and compress the disc spring of the spring unit 2.

The replacement temporary fixing jigs 51, 52 are connected to each other with a bolt 53 (see Figure 4; the same applies below) or the like, and the spring unit 2 is maintained in a compressed state.

As shown in Figure 10, the center hole jack 43 is unloaded. The upper nut n11 is removed and the PC steel rod 41 is pulled down to release the fastening between the upper plate 22 and the PC steel rod 41. The connection between the lower plate 21 and the lower capital 11 is released and the spring unit 2 is removed.

The new spring unit 2 is brought in and installed in a contracted state using the replacement temporary fixing jigs 51, 52. The PC steel rod 41 is inserted into the through hole of the upper plate 22 and fastened to the upper plate 22. A load is applied using the center hole jack 43, and the replacement temporary fixing jigs 51, 52 are removed. The center hole jack 43 is then unloaded to extend the spring unit 2, and the load is transferred from the supports 45, 46 to the spring unit 2. Finally, the supports 45, 46 are removed.

Next, replacement of the spring unit 2 of the vibration-isolating floating floor support spring expansion mechanism 100A will be described.
As shown in FIG. 17, after the spring unit 2, the reaction support structure 30 and the PC steel rod 41 are installed, supports 45, 46 (see FIG. 6) are installed.

As shown in Figure 9, set the center hole jack 43 on the PC steel bar 41 and remove the upper fixing nut n1. Load the center hole jack 43 to pull the PC steel bar 41 downward and compress the disc spring of the spring unit 2.

Next, as shown in FIG. 10, the intermediate nut n12 is tightened up to the upper fastening plate 32, and the center hole jack 43 is unloaded. The lower nut n13 is removed from the PC steel bar 41, and the center hole jack 43 is removed.

The connection between the lower plate 21 and the lower capital 11 is released, and the spring unit 2, reaction support structure 30, and PC steel bar 41 are removed as a unit.

The new spring unit 2 and reaction support structure 30 are brought in and installed with the spring unit 2 in a contracted state. The PC steel rod 41 is inserted into the through hole of the upper plate 22 and fastened to the upper plate 22. The center hole jack 43 is set and loaded, and the intermediate nut n12 is loosened once. The center hole jack 43 is then unloaded, the spring unit 2 is extended, and the load is transferred from the supports 45, 46 to the spring unit 2 side. Finally, the supports 45, 46 are removed.

In the vibration-proof floating floor support spring extension mechanism 100 and the construction method of the vibration-proof floating floor F thus configured, when constructing the floating floor F, a downward force is applied to the spring unit 2 by the jack set 3 to shorten the overall length of the spring unit 2. When constructing the floating floor F, the floating floor F is supported by the supports 45, 46. After at least a part of the floating floor F is completed (for example, the first layer of concrete has hardened), the downward force is removed from the spring unit 2 by using the jack set 3, the overall length of the spring unit 2 is lengthened, and the floating floor F is supported by the spring unit 2. Therefore, when constructing the floating floor F, it is the supports 45, 46 that support the weight of the floating floor F, and the spring unit 2 is insulated from the floating floor F, so that it is possible to prevent external forces caused by the construction work from acting on the spring unit 2 and adversely affecting the performance of the spring unit 2.

In addition, by introducing a preload into the spring unit 2 during manufacturing at the factory and shortening the spring length, the overall length of the spring unit 2 is shortened when it is delivered and installed, making it easier to handle and install.

Furthermore, when the center hole jack 43 is loaded while the upper plate 22 is not fixed to the upper capital 12, the PC steel rod 41 is pulled downward and moves downward relative to the reaction support structure 30. A downward force is applied to the upper plate 22 of the spring unit 2 connected to the PC steel rod 41, so the overall length of the spring unit 2 becomes shorter. In this state, when the PC steel rod 41 is fixed to the reaction support structure 30 in the current position by the intermediate nut n12, the overall length of the spring unit 2 remains short. In this state, the center hole jack 43 can be unloaded and removed. In this state, a tensile force is generated in the PC steel rod 41 between the position retaining member with the upper plate 22 and the intermediate nut n12.
Furthermore, from this state, if a center hole jack 43 is installed and a force greater than the load when the spring unit 2 is compressed is applied to apply a tensile force to the entire PC steel rod 41, and then the intermediate nut n12 that fixes the PC steel rod 41 to the reaction support structure 30 is loosened and the center hole jack 43 is unloaded, the overall length of the spring unit 2 will be increased.
By using the vibration-isolating floating floor support spring extension mechanism 100 in this manner, the length of the spring unit 2 can be easily adjusted.

In addition, when constructing the floating floor F with concrete, the weight of the floating floor F is supported by the supports 45, 46, which prevents horizontal displacement of the spring unit 2 caused by the construction work or drying shrinkage. This prevents the spring unit 2 from being subjected to loads in directions other than the load support direction, which could adversely affect the spring performance.

In addition, by using the spring unit 2 and jack set 3, the height and level of the top edge of the floating floor F can be adjusted by adjusting the spring height after concrete pouring for the floating floor F is completed.

In addition, by keeping the reaction support structure 30 and PC steel rods 41 permanently installed, if the spring units 2 need to be replaced, the center hole jack 43 and supports 45, 46 can be prepared and the replacement work can be carried out using the jack set 3. Instead of lifting the entire floor, the spring units 2 are compressed and the old spring units 2 are removed, making it possible to replace them one by one without affecting the surrounding area.

Next, the anti-vibration floating floor support spring extension mechanism related to variant 2 of one embodiment of the present invention and the method of replacing the spring unit of a vibration-proof floating floor using this anti-vibration floating floor support spring extension mechanism will be explained mainly using Figures 18 to 33.
In the following description of the modified examples, the same members as those described above are given the same reference numerals and the description thereof will be omitted.
As shown in Figures 18 to 22, the vibration-proof floating floor support spring extension mechanism 100B comprises a lower capital (lower body) 11B installed on a foundation mat (M shown in Figure 4), an upper capital (upper body) 12B on which the floating floor (F shown in Figure 4) is installed, a spring unit (second spring unit) 2B and a jack set (second jack set) 3B arranged between the lower capital 11B and the upper capital 12B, and a support structure (second temporary support member) 46B (see Figure 24) that supports the upper capital 12B.

As shown in FIG. 18, the lower capital 11B has a rectangular shape in plan view, but the shape can be set as desired.

Here, among the horizontal directions, the direction along one side 11c of the rectangular lower capital 11B (the left-right direction on the paper in FIG. 18) is defined as the X direction, and the direction along side 11d perpendicular to side 11c (the up-down direction on the paper in FIG. 18) is defined as the Y direction.

The upper surface of the lower capital 11B is formed with a notch 11j that is recessed toward the center from side 11c and side 11e opposite side 11c. In other words, the notch 11j extends in the Y direction from the inside of the lower capital 11B in a plan view. The notch 11j is formed on both sides of the lower capital 11B in the Y direction.

As shown in FIG. 19, the spring unit 2B has a lower plate 21B, an upper plate 22B, an intermediate plate 22C, a spring body (support spring) 23B, and a connecting pipe (connecting portion) 24.

As shown in FIG. 18, the lower plate 21B is circular in plan view, but the shape can be set as appropriate. The lower plate 21B has multiple bolt mounting holes 21h that penetrate in the vertical direction.

The lower plate 21B has cutouts 21j, 21k, and 21m that are recessed inward from both outer ends in the Y direction. The cutouts 21j, 21k, and 21m are arranged in this order in the X direction. The cutouts 21j, 21k, and 21m are formed on both sides of the lower plate 21B in the Y direction.

As shown in FIG. 19, the bolt c1 is inserted into the bolt mounting hole 21h of the lower plate 21B (see FIG. 18; the same applies below) and is screwed into the anchor bolt b1 provided in the lower capital 11B.

As shown in FIG. 21, the upper plate 22B is rectangular in plan view, but the shape can be set as appropriate. The upper plate 22B has a plurality of bolt mounting holes 22h that penetrate in the vertical direction. As shown in FIG. 19, the bolt c2 is inserted into the bolt mounting hole 21h (see FIG. 21; the same applies below) of the upper plate 22B and is screwed into the anchor bolt b2 of the upper capital 12B.

The intermediate plate 22C is disposed between the lower plate 21B and the upper plate 22B. As shown in FIG. 22, the intermediate plate 22C has a circular shape in a plan view, but the shape can be set as appropriate.

The intermediate plate 22C has cutouts 22j, 22k, and 22m that are recessed inward from both outer ends in the Y direction. The cutouts 22j, 22k, and 22m are arranged in this order in the X direction. The cutouts 22j, 22k, and 22m are formed on both sides of the intermediate plate 22C in the Y direction.

As shown in FIG. 19, the spring body 23B is disposed between the lower plate 21B and the middle plate 22C. In this embodiment, the spring body 23B is configured with multiple disc springs 23a arranged in the vertical direction. In a plan view, the disc springs 23a are circular, but the shape can be set as appropriate.

The connecting pipe 24 is tubular and extends vertically. The connecting pipe 24 connects the upper plate 22B and the middle plate 22C.

The jack set 3B has a fixing PC steel bar (second steel bar) 41B, a center hole jack (second jack) 43B, and a PC steel bar for the jack 41C.

The fixing PC steel rod 41B extends in the vertical direction. The fixing PC steel rod 41B connects the lower plate 21B and the middle plate 22C.

The center hole jack 43B is, for example, hydraulic. The center hole jack 43B can apply a downward force to the intermediate plate 22C.

In plan view, the center hole jack 43B has a circular shape, but the shape can be set as appropriate. A through hole (not shown) that penetrates vertically is formed in the center of the center hole jack 43B in plan view. A PC steel rod 41C for the jack is inserted into the through hole. The PC steel rod 41C for the jack is fixed to the lower plate 21B.

As shown in FIG. 18, the lower end of the fixing PC steel bar 41B is positioned on the inner edge in the Y direction of the notches 21j and 21m of the lower plate 21B. The lower end of the jack PC steel bar 41C is positioned on the inner edge in the Y direction of the notch 21k of the lower plate 21B.

As shown in FIG. 22, the upper end of the fixing PC steel bar 41B is located on the inner edge of the notches 22j and 22m of the intermediate plate 22C in the Y direction. The upper end of the jack PC steel bar 41C is located on the inner edge of the notch 22k of the intermediate plate 22C in the Y direction.

Next, a method for replacing the spring unit of the vibration-isolating floating floor using the above-mentioned vibration-isolating floating floor support spring expansion mechanism 100B will be described mainly with reference to Figures 23 to 33. This method involves replacing the existing spring unit with a new spring unit.
In the following description, of the spring units 2B, the existing one is referred to as an existing spring unit 2B1, and the new one is referred to as a new spring unit 2B2.

As shown in FIG. 23, an existing spring unit 2B1 is installed between the lower capital 11B and the upper capital 12B.

(Existing jack set installation process S1)
As shown in Fig. 24, the lower plate 21B and the intermediate plate 22C are connected by the PC steel bar 41C for the jack. Since the lower plate 21B and the intermediate plate 22C are formed with notches 21k and 22k, respectively, when the PC steel bar 41C for the jack is installed, it is sufficient to move the PC steel bar 41C for the jack horizontally in the Y direction. The PC steel bar 41C for the jack is positioned by abutting it against the inner edges of the notches 21k and 22k.
In addition, a center hole jack 43B is attached to the PC steel bar 41C for the jack, and the center hole jack 43B is placed on the intermediate plate 22C.

(Temporary support member installation process S2)
A support 46B is installed on the lower capital 11B. The support 46B supports (temporarily supports) the weight of the upper capital 12B and the floating floor F (see FIG. 4; the same applies below) above the upper capital 12B.

(Existing spring unit contraction process S3)
As shown in Fig. 25, the bolt c1 (see Fig. 24; the same below) that secures the lower plate 21B to the lower capital 11B and the bolt c2 (see Fig. 24; the same below) that secures the upper plate 22B to the upper capital 12B are removed. Then, as shown in Fig. 26, the center hole jack 43B is loaded to reduce the spring body 23B of the existing spring unit 2B1 to a predetermined height. In this state, the support 46B supports the upper capital 12B.

(Existing spring unit contraction holding process S4)
As shown in Fig. 27, the fixing PC steel bar 41B connects the lower plate 21B and the intermediate plate 22C to hold the spring body 23B in a contracted state at a predetermined height. Since the lower plate 21B and the intermediate plate 22C are formed with notches 21m, 21j, 22m, and 22j, respectively, the fixing PC steel bar 41B can be installed by horizontally moving the fixing PC steel bar 41B in the Y direction. The fixing PC steel bar 41B is positioned by abutting the inner edges of the notches 21m, 21j, 22m, and 22j.

(Existing spring unit removal process S5)
The center hole jack 43B is unloaded, and the center hole jack 43B (see FIG. 27) and the jack PC steel bar 41C (see FIG. 27) are removed as shown in FIG. 28, and the existing spring unit 2B1 is removed in a contracted state. When removing the jack PC steel bar 41C, it is sufficient to move the jack PC steel bar 41C horizontally in the Y direction through the cutout portions 21k, 22k of the lower plate 21B and the intermediate plate 22C.

(New spring unit installation process S6)
As shown in Figure 29, the new spring unit 2B2 is contracted, and the lower plate 21B and the middle plate 22C are connected with the fixing PC steel bar 41B to maintain the spring body 23B in a contracted state at a predetermined height. The new spring unit 2B2 thus constructed is carried in and installed on the lower capital 11B. Since the lower end of the fixing PC steel bar 41B protrudes from the lower plate 21B, it is installed so that the protruding portion is aligned with the Y-direction notch 11j of the lower capital 11B. By installing it in this manner, it becomes possible to remove the fixing PC steel bar 41B and the jack PC steel bar 41C horizontally after replacing the spring unit.

(New jack set installation process S7)
As shown in Figure 30, the lower plate 21B and the intermediate plate 22C are connected with the PC steel bar 41C for the jack. A center hole jack 43B is attached to the PC steel bar 41C for the jack, and the center hole jack 43B is placed on the intermediate plate 22C. When placing the PC steel bar 41C for the jack, it is sufficient to move the PC steel bar 41C for the jack horizontally in the Y direction through the cutouts 21k, 22k of the lower plate 21B and the intermediate plate 22C.

(Steel bar removal process S8)
As shown in Figure 31, the center hole jack 43B is loaded to apply a load slightly larger than that when the spring body 23B is compressed, so that the nuts of the fixing PC steel rods 41B (see Figure 30; the same applies below) can be loosened, and the fixing PC steel rods 41B are removed. When removing the fixing PC steel rods 41B, they can be moved horizontally in the Y direction through the cutouts 21m, 21j, 22m, and 22j of the lower plate 21B and the intermediate plate 22C.

(New spring unit extension process S9)
As shown in FIG. 32, the center hole jack 43B is unloaded, the spring body 23B is stretched, and the weight of the floating floor F is transferred to the new spring unit 2B2.

(New spring unit fixing process S10)
As shown in Figure 33, the lower plate 21B and the lower capital 11B are fixed with bolt c1. The upper plate 22B and the upper capital 12B are fixed with bolt c2. The center hole jack 43B (see Figure 32), the PC steel bar for the jack 41C (see Figure 32), and the support 46B are removed. When removing the PC steel bar for the jack 41C, it is sufficient to move the PC steel bar for the jack 41C horizontally in the Y direction through the cutout portions 21k, 22k of the lower plate 21B and the middle plate 22C.

In addition, in the process from the new jack set installation step S7 to the new spring unit extension step S9 after the new spring unit 2B1 is installed, in order to transfer the load to the new spring unit 2B2, in addition to the method of extending the spring body 23B with the center hole jack 43B, it is also possible to fill the gap between the upper plate 22B and the upper capital 12B with grout (not shown). The method of filling with grout has the advantage that the rise accuracy of the new spring unit 2B2 can be ensured without being affected by the installation accuracy of the upper capital 12B. However, when replacing a spring unit installed by filling with grout, the grout must be removed.

Next, a method for constructing a vibration-isolating floating floor using the above-mentioned vibration-isolating floating floor support spring expansion mechanism 100B will be described.
The (new) spring unit installation step S6 shown in the method for replacing the spring unit of the vibration-isolating floating floor described above is carried out.

(Temporary support member installation process)
Next, a support structure 46B capable of supporting the floating floor F described below is installed.

(Upper body installation process)
An upper capital 12B is installed above the spring unit 2B2 and the jack set 3B.

(Floating floor construction process)
A floating floor F is constructed above the upper capital 12B.

Next, the (new) jack set installation process S7, the steel bar removal process S8, the (new) spring unit extension process S9, and the (new) spring unit fixing process S10 are carried out as shown in the method for replacing the spring unit of the vibration-isolation floating floor described above.
The spring unit extension process S9 and the spring unit fixing process S1 enable the spring unit 2B2 to support the weight of the floating floor F (load transfer process).

When adjusting the height of the top level of the floating floor F, after carrying out the steps from the existing jack set installation step S1 to the existing spring unit contraction step S3 described above, a clamping material (steel plate, etc.) of the required thickness is installed between the upper plate 22B and the upper capital 12B, and the procedure of the new spring unit extension step S9 and the new spring unit fixing step S10 described above is followed, or the gap between the installed clamping material and the upper capital 12B is filled with grout material to restore the structure.

In the vibration-proof floating floor support spring extension mechanism 100B configured in this manner, there is no need to install a support structure for the jack reaction force separately from the spring unit 2B. Therefore, the spring unit 2B can be extended or contracted at the location where the spring unit 2B is installed, making it easier to install and replace the spring unit 2B.

The force that connects the lower plate 21B and the intermediate plate 22C with the fixing PC steel rod 41B to contract the spring body 23B can be transferred to the center hole jack 43B by loading the center hole jack 43B, and the connection between the lower plate 21B and the intermediate plate 22C can be released and the center hole jack 43B can be unloaded to expand the spring body 23B.

In addition, in the floating floor construction process, the weight of the floating floor F is supported by the support 46B. After at least a portion of the floating floor F is completed (for example, the first layer of concrete has hardened), the center hole jack 43B is unloaded in the load transfer process, the spring unit 2B extends, and the spring unit 2B supports the floating floor F. Therefore, during construction of the floating floor F, it is the second temporary support member such as the support 46B that supports the weight of the floating floor F, and the spring unit 2B is insulated from the floating floor F, so that it is possible to prevent external forces caused by the construction work from acting on the second spring unit and adversely affecting the performance of the spring unit 2B.

The spring unit 2B can be held in a contracted state using the fixing PC steel rod 41B, and the center hole jack 43B is used only when expanding or contracting the spring unit 2B (momentarily). In other words, after one spring unit 2B is contracted with the center hole jack 43B, the center hole jack 43B can be used to contract another spring unit 2B. Therefore, there is no need to prepare a number of center hole jacks 43B for each spring unit 2B.

Because the lower plate 21B and the intermediate plate 22C have cutouts 21j, 21k, 21m, 22j, 22k, and 22m, respectively, when installing and removing the fixing PC steel rod 41B and the jack PC steel rod 41C, the fixing PC steel rod 41B and the jack PC steel rod 41C can be moved horizontally in the Y direction. This eliminates the need to lift the fixing PC steel rod 41B and the jack PC steel rod 41C upwards, improving workability.

The shapes and combinations of the components shown in the above-mentioned embodiment are merely examples, and may be modified in various ways based on design requirements, etc., without departing from the spirit of the present invention.

2, 2A...Spring unit (first spring unit)
3...Jack set (first jack set)
11...Lower capital (lower body)
12...Upper capital (upper body)
21, 21A... Lower plate 22... Upper plate 23... Spring body (support spring)
30... Reaction support structure 31... Lower fixed plate 32... Upper fastening plate 33... Support frame 41... PC steel bar (first steel bar)
43...Center hole jack (first jack)
45, 46... Shoring (first temporary support member)
100, 100A... Anti-vibration floating floor support spring extension mechanism F... Floating floor M... Foundation mat (foundation)
n12...Intermediate nut (position retaining member)

Claims (2)

A vibration-proof floating floor support spring extension mechanism used when installing a floating floor above a foundation,
A lower body installed on the foundation;
an upper body disposed above the lower body and on which a floating floor is installed;
a first spring unit including a lower plate fixed to the lower body, an upper plate arranged below the upper body so as to be able to support the upper body, and a support spring arranged between the lower plate and the upper plate;
a first set of jacks fixed to the lower body or the lower plate and capable of applying a downward force to the upper plate;
A first temporary support member capable of supporting the floating floor,
The first jack set includes:
A reaction support structure fixed to the lower body or the lower plate;
a first steel rod connected to the upper plate;
A first jack capable of applying a downward force to the first steel bar;
A position retaining member capable of fixing and releasing the first steel rod to any position of the reaction support frame,
The reaction support structure has an upper fastening plate disposed below the upper plate,
The position retaining member is provided below the upper fastening plate,
An anti-vibration floating floor support spring extension mechanism characterized in that the first jack is detachably attached to the lower end of the first steel bar. a spring unit installation step of installing a first spring unit on the lower body;
a jack set installation process for installing a first jack set including a first jack, a reaction support structure, and a first steel bar on the lower body and connecting the first steel bar of the first jack set to an upper plate of the first spring unit;
A temporary support member installation process for installing a temporary support member capable of supporting the floating floor;
an upper body installation process of installing an upper body above the first spring unit and the first jack set;
a downward force applying step of loading the first jack of the first jack set to pull the first steel rod downward and apply a downward force to the upper plate of the first spring unit, and operating a position-retaining member provided on the first jack set to hold the first steel rod at a predetermined position on the reaction support frame ;
a floating floor construction process in which the floating floor is constructed above the upper body and the floating floor is supported by the temporary support members;
a load transfer process of removing the first jack, eliminating the downward force applied to the upper plate, and supporting the floating floor with the first spring unit.

Images