New foundation for machinery installation

Abstract

To reduce a range where an existing slab is chipped when a new foundation where machinery is installed in an existing slab is newly provided.SOLUTION: A new foundation 100 includes a deformed stud 102 joined to a pile head part 62 exposed by chipping an existing slab 10 right above the pile head part 62, and a reinforced-concrete part 110 that is constructed right above the pile head part 62 and in which the deformed stud 102 is embedded.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a new foundation for installing machinery. [Background technology]

[0002] Patent Document 1 discloses a technique for constructing a foundation structure using the rooftop framework of an existing building to install a tower crane or other equipment used in renovation work, etc. In this prior art, the concrete covering the top surface of the framework of the existing structure is stripped away, exposing the top surface of the upper flange of the steel beam. Stud bolts are then placed vertically in a desired position on the top surface of the upper flange. The recess where the concrete was stripped away is then backfilled with concrete to repair the waterproofing layer, and the floor concrete covering the top surface of the framework is repaired by backfilling with waterproofing layer holding concrete. The stud bolts can then be used to install the desired machinery.

[0003] Patent Document 2 discloses a technique related to a rooftop equipment foundation structure in which an equipment foundation for installing rooftop equipment is constructed on a roof slab. In this prior art, the equipment foundation is configured with a columnar portion formed by pouring concrete into a cylindrical member erected on a beam supporting the roof slab or a formwork member erected on the beam, and the cylindrical member has a steel pipe portion, and an anchoring portion that is anchored to the concrete of the roof slab is fixed to the lower outer periphery of the steel pipe portion. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-80824 [Patent Document 2] Patent Publication No. 2021-11700 Summary of the Invention [Problem to be solved by the invention]

[0005] When a new foundation for machinery is installed on an existing slab, a new slab may be constructed around the bottom of the new foundation to handle the bending moment that occurs during an earthquake. To construct this new slab, a large area of ​​the existing slab must be removed. However, such a large area of ​​the slab requires extensive removal and repair of the existing waterproofing layer, which can increase the risk of water leakage.

[0006] In view of the above, an object of the present invention is to reduce the area of ​​a slab that needs to be chipped when a new foundation for installing machinery on an existing slab is constructed. [Means for solving the problem]

[0007] The first aspect is a new foundation for installing machinery, which comprises an anchor joined to the column capital exposed by chipping away the existing slab directly above the column capital, and a reinforced concrete section constructed directly above the column capital and in which the anchor is embedded.

[0008] In the first type of new foundation for installing machinery, the anchors attached to the column capitals embedded in the reinforced concrete bear the bending moment, so there is no need to build a new slab that is integrated with the periphery and bottom end of the new foundation, or the area where the new slab is built can be reduced. Therefore, the area that needs to be chipped off from the existing slab is smaller than when no anchors are installed.

[0009] A second aspect is the new foundation for installing machinery according to the first aspect, in which the reinforced concrete section is embedded with a plurality of upper main reinforcements arranged in the longitudinal direction of the reinforced concrete section and spaced apart in the width direction of the reinforced concrete section, a plurality of lower main reinforcements arranged in the longitudinal direction and spaced apart in the width direction below the upper main reinforcements, and a plurality of shear reinforcement bars surrounding the upper main reinforcements and lower main reinforcements and spaced apart in the longitudinal direction.

[0010] In the new foundation for installing machinery of the second embodiment, bending moments are effectively transmitted to the anchors by the upper end main reinforcement, the lower end main reinforcement, and the shear reinforcement embedded in the reinforced concrete portion.

[0011] The third aspect is a new foundation for installing machinery as described in the first or second aspect, in which the existing waterproof layer is removed together with the slab directly above the column capital, and a repair waterproof layer is formed from above the end of the existing waterproof layer that has not been removed to the side of the reinforced concrete section.

[0012] In the third embodiment of the new foundation for installing machinery, the area of ​​the slab that is chipped is small, and therefore the area of ​​the existing waterproof layer that is removed along with the slab directly above the column capital is small, reducing the risk of water leakage. [Effects of the Invention]

[0013] According to the present invention, when constructing a new foundation for installing machinery on an existing slab, the area of ​​the existing slab that needs to be chipped can be reduced. [Brief explanation of the drawings]

[0014] [Figure 1] (A) is a front view showing the state in which the machine is installed on the newly constructed foundation, and (B) is a plan view. [Figure 2] This is a cross-sectional view of the new foundation along the X direction. [Figure 3] A cross-sectional view of the new foundation along the Y direction. [Figure 4] (A) is a cross-sectional view of the slab before the new foundation is constructed, and (B) is a cross-sectional view of the slab after chipping away and welding a special shaped stud to the exposed column head. [Figure 5] 10A is a cross-sectional view of a new foundation of a first modified example taken along the X direction, and FIG. 10B is a perspective view of an anchor. [Figure 6] FIG. 10 is a cross-sectional view of a new foundation of a second modified example taken along the X direction. [Figure 7] FIG. 10 is a cross-sectional view of a newly constructed foundation of a comparative example taken along the X direction. DETAILED DESCRIPTION OF THE INVENTION

[0015] <Embodiment> A new foundation for installing machinery according to one embodiment of this invention will be described. Two directions perpendicular to the horizontal direction are designated as the X direction and the Y direction, and are indicated by the arrows X and Y, respectively. The vertical direction perpendicular to the X direction and the Y direction is designated as the Z direction, and is indicated by the arrow Z.

[0016] [structure] First, we will explain the structure of the new foundation for installing machinery.

[0017] The new foundations 100 shown in Figure 1 (see also Figures 2 and 3) are newly constructed on an existing reinforced concrete slab 10 (see also Figure 4(A)) on the roof of a building, and two of them are installed at an interval along the X direction. These new foundations 100 are approximately rectangular parallelepipeds with the Y direction as the longitudinal direction. To be precise, as shown in Figures 2 and 3, the upper end of the new foundations 100 has wide portions 150, 152 that protrude in the X and Y directions and are wider.

[0018] As shown in Fig. 1, two steel framed pedestals 80 are suspended across these new foundations 100. The pedestals 80 are fastened to pedestal anchors 82 (Figs. 2 and 3) protruding from the new foundations 100. Equipment 90, such as an emergency generator as an example of machinery, is fixed to the pedestals 80.

[0019] As shown in Figure 1(A), the existing slab 10 of this embodiment is supported by steel-framed beams 50 and steel-framed columns 60 (see also Figures 2, 3, and 4(A)). The new foundations 100 are provided directly above the column capitals 62 of the columns 60 (see also Figures 2 and 3).

[0020] 2 and 3, the new foundation 100 is composed of a deformed stud 102, which is an example of an anchor, and a reinforced concrete section 110. The deformed stud 102 has its lower end welded to the column capital 62 of the column 60, which is exposed by chipping away the existing slab 10 (see also FIG. 4(B)). The deformed stud 102 protrudes upward and is embedded in the reinforced concrete section 110.

[0021] A plurality of upper end main reinforcements 120, lower end main reinforcements 122, and shear reinforcement bars 124 are embedded in the reinforced concrete section 110. The upper end main reinforcements 120 are arranged in the Y direction, which is the longitudinal direction of the rectangular parallelepiped reinforced concrete section 110, and are arranged at intervals in the X direction, which is the width direction of the reinforced concrete section 110. The lower end main reinforcements 122 are arranged in the Y direction below the upper end main reinforcements 120, and are arranged at intervals in the X direction. The shear reinforcement bars 124 surround the plurality of upper end main reinforcements 120 and lower end main reinforcements 122, and are arranged at intervals in the Y direction as shown in FIG. 3 .

[0022] As shown in Fig. 3, both longitudinal sides of the upper end main reinforcement 120 in this embodiment are curved downward, forming an inverted U shape when viewed from the X direction. Both longitudinal sides of the lower end main reinforcement 122 in this embodiment are curved upward, forming a U shape when viewed from the X direction. The vertically arranged both side portions of the upper end main reinforcement 120 and the lower end main reinforcement 122 are connected by a lap joint.

[0023] As shown in FIGS. 1 and 3, the upper end of the deformed stud 102 is embedded within the area surrounded by the upper end main reinforcement 120, the lower end main reinforcement 122, and the shear reinforcement 124.

[0024] In this embodiment, in addition to the upper end main reinforcement 120, the lower end main reinforcement 122, and the shear reinforcement 124, reinforcement bars 300 and 302 are embedded in the wide portion 150 protruding in the X direction (see FIG. 2). Similarly, reinforcement bars 310 and 312 are embedded in the wide portion 152 protruding in the Y direction (see 3).

[0025] As shown in FIG. 2, the reinforcing bars 300 embedded in the wide portion 150 are arranged along the Y direction with vertical spacing. Reinforcing bars 302 are roughly C-shaped, surrounding the upper and lower reinforcing bars 300. The reinforcing bars 302 extend inward beyond the wide portion 150 and then bend downward. Similarly, as shown in FIG. 3, the reinforcing bars 310 embedded in the wide portion 152 are arranged along the Y direction with vertical spacing. The reinforcing bars 312 are roughly C-shaped, surrounding the upper and lower reinforcing bars 310. The reinforcing bars 312 extend inward beyond the wide portion 152 and then bend downward.

[0026] As shown in Figures 2 and 3, an existing waterproof layer 20 and a repair waterproof layer 130 are formed on the existing slab 10, and an existing protective concrete layer 30 and a new protective concrete layer 33 are formed on top of them (see also Figure 4(A)). The existing waterproof layer 20 and the protective concrete layer 30 directly above the column capital 62 of the column 60 have been removed. The area from which the existing waterproof layer 20 has been removed is slightly larger than the area from which the existing slab 10 has been chipped (see Figure 4(B)). The area from which the protective concrete layer 30 has been removed is also slightly larger than the area from which the existing waterproof layer 20 has been removed. A repair waterproof layer 130 is formed on the area from which the existing waterproof layer 20 has been removed and on the side surface 112 of the reinforced concrete section 110. An end 132 of the repair waterproof layer 130 is overlapped on the end 22 of the existing waterproof layer 20 that has not been removed. Furthermore, a new protective concrete layer 33 is provided on top of the repair waterproof layer 130, in other words, in the area where the existing protective concrete layer 30 was removed.

[0027] [Construction method] Next, an example of a method for constructing the new foundation 100 will be described.

[0028] Fig. 4(A) shows a reinforced concrete slab 10 before the construction of a new foundation 100. As described above, an existing waterproof layer 20 is formed on the existing slab 10 that constitutes the skeleton, and a protective concrete layer 30 is formed on top of that.

[0029] As shown in Figure 4(B), first, the slab 10 directly above the column capital 62 of the column 60 is chipped and removed to expose the column capital 62. At the same time, the existing waterproof layer 20 and protective concrete layer 30 directly above the column capital 62 are also removed. As mentioned above, the area from which the existing waterproof layer 20 is removed is slightly larger than the area from which the existing slab 10 is chipped, and the area from which the protective concrete layer 30 is removed is slightly larger than the area from which the existing waterproof layer 20 was removed. Then, a deformed stud 102 is welded to the exposed column capital 62.

[0030] As shown in FIGS. 2 and 3, a plurality of upper end main reinforcements 120, lower end main reinforcements 122, and shear reinforcement bars 124 are arranged, and concrete is poured to construct the reinforced concrete section 110.

[0031] After the concrete has hardened, a repair waterproof layer 130 is formed from the end 22 of the existing waterproof layer 20 to the side 112 of the reinforced concrete portion 110. Also, a new protective concrete layer 33 is constructed.

[0032] [Effect] Next, the operation of this embodiment will be described.

[0033] First, a new foundation 900 for a comparative example in which the deformed studs 102 joined to the column capital parts 62 of the reinforced concrete parts 110 shown in FIG. 7 are not embedded will be described.

[0034] In the case of the new foundation 900 of the comparative example, during an earthquake, a force F is transmitted from the equipment 90 to the new foundation 900 via the mounting frame 80, and a bending moment is generated in the new foundation 900.

[0035] In order to handle the bending moment acting on this new foundation 900, a new slab 930 is constructed around the lower end of the new foundation 900, and is integrated with the new foundation 900. Reinforcement bars 910 are arranged in the new slab 930 along the horizontal direction.

[0036] In this way, a large area of ​​the existing slab 10 is chipped away in order to construct the new slab 930 around the lower end of the new foundation 900. Since a large area of ​​the existing slab 10 is chipped away, a large area of ​​the existing waterproof layer 20 is removed, and even if the existing waterproof layer 20 is repaired with the repair waterproof layer 130, there is a risk of increased risk of water leakage.

[0037] In contrast, in the new foundation 100 of this embodiment, the force F is transmitted from the equipment 90 to the new foundation 100 via the mounting frame 80, causing a bending moment in the new foundation 100. However, the bending moment is borne by the deformed studs 102 joined to the column capital parts 62 embedded in the reinforced concrete section 110. Therefore, there is no need to construct a new slab 930 (see FIG. 7) that is integrated with the lower end of the new foundation 100 to handle the bending moment.

[0038] Therefore, since it is not necessary to chip a wide area of ​​the slab 10 (see FIG. 7) to construct the new slab 930 (see FIG. 7), the chipping area of ​​the slab 10 is small. In this way, the chipping area of ​​the slab 10 is small, and the area of ​​the existing waterproof layer 20 that is removed is small, so the risk of water leakage is reduced.

[0039] In addition, the bending moment is effectively transmitted to the deformed stud 102 by the upper end main reinforcement 120, the lower end main reinforcement 122, and the shear reinforcement 124 embedded in the reinforced concrete portion 110 of the new foundation 100.

[0040] <Modification> Next, a modification of this embodiment will be described.

[0041] [First Modification] As shown in FIG. 5(B), in the new foundation 101 of the first modified example, the anchor 200 has a structure in which a plurality of deformed steel bars 212 (three in the figure) are joined to the side surface of a plate portion 210.

[0042] As shown in Figure 5(A), in the new foundation 101, the plate portion 210 of the anchor 200 is welded to the column capital portion 62 exposed by chipping away the existing slab 10. The deformed steel bar 212 of the anchor 200 protrudes upward and is embedded in the reinforced concrete portion 110.

[0043] In this way, by welding the plate portion 210 of the anchor 200 to the column capital portion 62, a plurality of deformed reinforcing bars 212 can be installed, resulting in good construction efficiency.

[0044] [Second Modification] 6, in the new foundation 103 of the second modified example, the slab 10 is supported by reinforced concrete beams 270 and reinforced concrete columns 260. The new foundation 103 is provided directly above the column capitals 262 of the columns 260.

[0045] The post-installed anchor 272 has its lower end 273 fixed to the column capital 262 exposed by chipping away at the existing slab 10. The column capital 262 has also been chipped away to form a recess 264. The new foundation 103 has a protrusion 115 at its lower end that fits into the recess 264.

[0046] In this modification, bending moments are handled by the post-installed anchor 272 and the protrusion 115. Note that the recess 264 and the protrusion 115 do not necessarily have to be provided.

[0047] <Other> The present invention is not limited to the above embodiment.

[0048] For example, in the above embodiment, a new slab was not constructed around the lower end of the new foundation 100, but a new slab may be constructed as necessary. Even when a new slab is constructed, the bending moment is handled by the anchors joined to the column heads, so the construction area of ​​the new slab is smaller than when anchors are not installed, i.e., the area where the existing slab 10 is chipped is smaller.

[0049] Furthermore, in the above embodiment, the new foundation 100 is constructed on the existing slab 10 on the roof of the building, but this is not limited to this. The new foundation 100 may also be constructed on the existing slab 10 inside the building. Note that in the case of an existing slab 10 inside the building, an existing waterproof layer 20 may not be provided. Even in this case, the area of ​​the existing slab 10 that is chipped is small, which is preferable because it has little impact on the floors below, for example.

[0050] Furthermore, the present invention can be embodied in various forms without departing from the spirit and scope of the present invention. A plurality of embodiments and modifications can be implemented in combination as appropriate. [Explanation of symbols]

[0051] 10 Slabs 20 Existing waterproof layer 22 End 62 Column head 100 New Foundation 102 Irregular shaped stud (an example of an anchor) 110 Reinforced concrete section 112 Side 120 Top main bar 122 Bottom main reinforcement 124 Shear reinforcement 130 Repair waterproof layer

Claims

1. A first anchor joined to the column capital exposed by chipping off the existing slab directly above the column capital; a reinforced concrete section constructed directly above the column capital and in which the first anchor is embedded; a second anchor having a lower end embedded in the reinforced concrete portion and an upper end protruding from an upper surface of the reinforced concrete portion; New foundation for machinery installation.

2. The reinforced concrete portion includes: A plurality of upper end main reinforcements arranged in the longitudinal direction of the reinforced concrete portion and spaced apart in the width direction of the reinforced concrete portion; a plurality of lower end main reinforcements arranged in the longitudinal direction and spaced apart in the width direction below the upper end main reinforcements; A plurality of shear reinforcements surrounding the upper end main reinforcement and the lower end main reinforcement and spaced apart in the longitudinal direction; is buried, A new foundation for installing machinery according to claim 1.

3. The upper end of the first anchor is arranged within the range surrounded by the upper end main reinforcement, the lower end main reinforcement, and the shear reinforcement. A new foundation for installing machinery according to claim 2.

4. The first anchor is a plate portion welded to the column capital portion; A plurality of deformed steel bars joined to the side surfaces of the plate portion; having A new foundation for installing machinery according to any one of claims 1 to 3.

5. A recess is formed in the column capital, The reinforced concrete portion has a protrusion at its lower end that fits into the recess. A new foundation for installing machinery according to any one of claims 1 to 4.

6. The existing waterproof layer is removed together with the existing slab directly above the column capital, A repair waterproof layer is formed from the end of the existing waterproof layer that has not been removed to the side of the reinforced concrete section, The end of the repair waterproof layer is overlapped on the end of the existing waterproof layer. A new foundation for installing machinery according to any one of claims 1 to 5.

7. An existing protective concrete layer is formed on the existing waterproof layer, The existing waterproof layer and the existing protective concrete layer are removed together with the slab, A new protective concrete layer is formed on the repair waterproof layer. A new foundation for installing machinery according to claim 6.

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