Support special for combined grid cast-in-place concrete hollow floor

Abstract

The utility model discloses a special bracket for a combined grid cast-in-place concrete hollow floor, which belongs to the technical field of civil engineering and is provided with a supporting part, a left limiting part, a right limiting part and supporting legs, the supporting part is horizontally arranged and used for supporting the box type core mold. The left limiting part and the right limiting part are arranged on the left side and the right side of the supporting part correspondingly and used for limiting an extending part formed by covering an upper cover and a lower cover of the box type core mold on the longitudinal side or the transverse side of the box type core mold, and deviation of the box type core mold in the horizontal direction is limited. The supporting legs are arranged at the bottom of the supporting part and used for being fixed to the bottom formwork. The special support can be used for replacing a cushion block (or a horse stool) in a traditional scheme to position the combined grid, and the problems of deviation and floating of the box type core mold in an original construction technology are solved.

Description

TECHNICAL FIELD

[0001] The utility model belongs to civil engineering technical field, concretely relates to a special support of combined grid cast-in-situ concrete hollow floor. BACKGROUND

[0002] Floor is the horizontal structural system in building structure, which together with vertical component and lateral force resisting component constitutes the whole space structural system of building structure. It transmits the vertical load of floor to vertical component and transmits horizontal load (wind force, earthquake force) to lateral force resisting component. According to construction method, floor can be divided into cast-in-situ floor, fabricated floor and assembled monolithic floor. Cast-in-situ floor has good integrity, large rigidity, good seismic performance, flexible structure arrangement and strong adaptability. Chinese code requires that cast-in-situ floor should be used in high-rise building. Combined grid cast-in-situ concrete hollow floor is a kind of cast-in-situ floor, as shown in the cast-in-situ floor formed by a certain type of box formwork, which can be regarded as a recess in a solid slab, which saves the concrete in the tensile zone, and the part without hollowing is a small beam or called ribbed beam. Specifically, the floor slab of combined grid cast-in-situ concrete hollow floor is a flexural member, which bears pressure by the concrete in the compression zone and bears tension by the steel bars in the tensile zone. The floor slab of combined grid cast-in-situ concrete hollow floor replaces the concrete with small stress in the cast-in-situ concrete floor by using hole core formwork to form a good I-shaped section or T-shaped section, and the main load-bearing component is the ribbed beam with I-shaped section or T-shaped section, which reduces the self-weight of floor, the amount of steel bars and concrete. Figure 1

[0003] Due to the cavity structure of the floor slab in combined grid cast-in-situ concrete hollow floor, the hollow floor slab has good heat preservation, heat insulation and sound insulation performance. The construction process of combined grid cast-in-situ concrete hollow floor generally includes: measurement and setting-out, erection of formwork support system and installation of formwork, positioning and setting-out of hollow floor slab, binding of bottom steel bars of floor slab, binding of ribbed beam steel bars, installation of hole core formwork (or installation of combined grid), binding of slab steel bars, hole opening, fixing of combined grid anti-floating points, concrete construction and maintenance, and formwork removal. At present, the hole core formwork mainly includes circular thin-walled barrel core formwork and box core formwork. During construction, the box core formwork is light in weight, and it is easy to float up and shift left and right under the impact of concrete during cast-in-situ concrete construction, as shown in Figure 1 The upper and lower flanges of the I-shaped section formed by the box core formwork of a certain type are cast-in-situ, and the floating or left and right shifting of the box core formwork will cause deformation of the I-shaped section, which will lead to abnormal stress distribution of floor.

[0004] ​To address the issue of misalignment of the empty box core mold during concrete pouring, the existing solution is the top pressure bar method. This involves placing a modular grid according to the drawing's position, using appropriate pads (or stirrups) to position the grid during assembly, ensuring sufficient concrete thickness (protective layer thickness) at the bottom of the grid, and placing a continuous reinforcing bar (diameter not less than Φ12) at the top of each row of modular grids as an anti-buoyancy reinforcement (or capping reinforcement). Then, a wire (not less than #12) is used to pass through the bottom formwork of the rib beam (holes are drilled in the bottom formwork) to connect and fix the anti-buoyancy reinforcement at the top of the modular grid to the support system below the bottom formwork. In other words, the existing solution uses pads or stirrups to support the box core mold and uses capping reinforcement to press and fix it in place. However, this solution has three drawbacks: firstly, the anti-buoyancy reinforcement can only restrict the vertical displacement of the core mold, failing to meet the requirement that the allowable deviation in straightness should not exceed 3 / 1000 and should not exceed 15mm. Secondly, the poor processing precision of the pads or iron supports makes it difficult to strictly control their height, easily leading to inconsistent heights of the box-shaped core mold. Therefore, custom-made supports or pads are needed to ensure that the box-shaped core mold maintains the same height. Thirdly, while using anti-buoyancy reinforcements for anti-buoyancy, it is impossible to completely prevent the box-shaped core mold from rotating around the anti-buoyancy reinforcements, which will cause uneven concrete thickness at the bottom of the box-shaped core mold. Utility Model Content

[0005] In view of this, this utility model proposes a special support for a combined grid cast-in-place hollow concrete floor slab. Using this special support can ensure the installation position accuracy of the box-shaped core mold, solve the problem of the box-shaped core mold floating upward and shifting left and right during the concrete pouring process, and ensure construction quality.

[0006] The present invention adopts the following technical solution:

[0007] A special support for a combined grid-type cast-in-place hollow concrete floor slab, the special support being provided with a support part, a left limiting part, a right limiting part, and support legs;

[0008] The support portion is horizontally arranged to support the box-shaped core mold;

[0009] The left limiting part and the right limiting part are respectively disposed on the left and right sides of the support part, and are used to limit the extension formed by the upper cover and lower cover of the box-shaped core mold on both longitudinal or transverse sides of the box-shaped core mold, thereby limiting the horizontal displacement of the box-shaped core mold.

[0010] The support leg is located at the bottom of the support part and is used to fix it to the bottom template.

[0011] Furthermore, the left limiting part and the right limiting part have the same structure, both including a side wall and a top wall;

[0012] The bottom of the side wall is fixedly connected with the top of the supporting part, and the top of the side wall extends vertically upward relative to the bottom of the supporting part;

[0013] One end of the top wall is fixedly connected with the top of the side wall, and the other end extends horizontally to the middle part of the supporting part, so that the top wall and the side wall form a hook-shaped limiting structure;

[0014] The box core mold is limited between the side wall of the left limiting part and the side wall of the right limiting part.

[0015] Further, the bottom of the leg is provided with a fastening part with a screw hole;

[0016] The special support and the bottom form are fixed by a screw passing through the screw hole.

[0017] Further, the leg is fixed to the bottom of the supporting part by welding.

[0018] Further, the distance between the side wall of the left limiting part and the side wall of the right limiting part is 460mm.

[0019] Further, the supporting part, the left limiting part and the right limiting part are made of hot-rolled steel plate punched.

[0020] Beneficial effects:

[0021] 1. A combined grid cast-in-place concrete hollow floor special support, the special support is provided with a supporting part, a left limiting part, a right limiting part and a leg; the supporting part is horizontally arranged and used for supporting a box core mold; the left limiting part and the right limiting part are arranged on the left side and the right side of the supporting part respectively and used for limiting an extension part formed by upper and lower covers of the box core mold on the two sides of the box core mold in the longitudinal direction or the transverse direction, and limiting horizontal deviation of the box core mold; the leg is arranged at the bottom of the supporting part and used for being fixed with a bottom form.

[0022] In this way, the special support can be used to replace the cushion block (or horse stool) in the traditional scheme to position the combined grid, specifically, the special support can support the box core mold through the supporting part, and at the same time, limit the box core mold through the left limiting part and the right limiting part, cooperate with the traditional top pressing steel, limit the displacement of the box core mold in the transverse (horizontal) direction and the longitudinal (vertical) direction respectively, ensure the installation position accuracy of the box core mold, ensure the control of the thickness of the upper and lower flange cast-in-place layer, ensure the uniformity of the cast-in-place layer concrete thickness, ensure the uniformity of the ribbed beam I-shaped section, and solve the problems of deviation and floating of the box core mold in the original construction process.

[0023] 2. The left limiting part and the right limiting part have the same structure, both including a side wall and a top wall; the bottom of the side wall is fixedly connected to the top of the support part, and the top of the side wall extends vertically upward relative to the bottom of the support part; one end of the top wall is fixedly connected to the top of the side wall, and the other end extends horizontally towards the middle of the support part, so that the top wall and the side wall form a hook-shaped limiting structure; the box-shaped core mold limit is located between the side wall of the left limiting part and the side wall of the right limiting part.

[0024] In this way, the edges of the box-shaped core mold (i.e., the extension formed by the upper and lower covers of the box-shaped core mold) can be inserted into the hooks of the special bracket, restricting the displacement of the core mold. At the same time, the top wall also plays a role in preventing buoyancy. Combined with the pressure bar reinforcement, this achieves the purpose of controlling the installation accuracy of the box-shaped core mold and preventing buoyancy. Moreover, the hooks on both sides restrict the box-shaped core mold from deflecting around the pressure bar reinforcement. Furthermore, since there is a certain distance between the hooks on both sides, after placing one side of the box-shaped core mold into the bracket, the box-shaped core mold is then moved horizontally, and the other side is also inserted into the bracket hook, thus completing the assembly of the bracket and the box-shaped core mold. Using this special bracket, positioning is simple, and installation is quick and easy.

[0025] 3. The bottom of the support leg is equipped with a fastening part with screw holes; the special bracket is fixed to the bottom formwork by screws passing through the screw holes. Thus, since the dimensions of the box-type core mold match the spacing of the rib beams during construction, only the distance between the hook and the protective layer of the rib beam or frame beam stirrups needs to be measured. The special bracket can then be fixed with screws, ensuring the installation position of the box-type core mold between the rib beams without the need for layout lines. This special bracket has a simple structure, is easy to install, and achieves good fixing effect with just screws. Installation is fast, improving on-site installation quality and construction efficiency. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the cross-section of a composite grid cast-in-place concrete hollow floor slab structure in the prior art;

[0027] Figure 2 This is a structural schematic diagram of a special support for a combined grid cast-in-place hollow concrete floor slab provided in an embodiment of this utility model;

[0028] Figure 3 This is a front view of a special support for a combined grid cast-in-place hollow concrete floor slab provided in an embodiment of this utility model;

[0029] Figure 4 This is a top view of a special support for a combined grid cast-in-place hollow concrete floor slab provided in an embodiment of this utility model;

[0030] Figure 5 This is a side view of a special support for a combined grid cast-in-place hollow concrete floor slab provided in an embodiment of this utility model;

[0031] Figure 6The four 500*450 series box core mold combined principle schematic diagrams provided by the embodiment of the utility model;

[0032] Figure 7 The front view of a single 500*450*115 box core mold provided by the embodiment of the utility model;

[0033] Figure 8 The left side view of a single 500*450*115 box core mold provided by the embodiment of the utility model;

[0034] Figure 9 The front view of a single 500*450*260 box core mold provided by the embodiment of the utility model; Figure 10 The left side view of a single 500*450*260 box core mold provided by the embodiment of the utility model;

[0035] Figure 11 The floor stress distribution schematic diagram when the core mold offset exceeds the specification requirement provided by the utility model;

[0036] Figure 12 The floor stress distribution diagram when the core mold offset is within the specification requirement provided by the utility model; 1-support part, 201-side wall, 202-top wall, 3-leg, 301-fastening part, 302-screw hole, 4-upper cover, 5-lower cover, 6-extension part. DETAILED DESCRIPTION

[0037] The utility model is described in detail below in combination with the drawings and examples.

[0038] Referring to Figures 2-12 The special support provided by the embodiment is provided with a support part 1, a left limiting part, a right limiting part and a leg 3, wherein:

[0039] The support part 1 is horizontally arranged and used for supporting the box core mold; the left limiting part and the right limiting part are respectively arranged on the left side and the right side of the support part 1 and used for limiting the extension part 6 formed by the upper cover 4 and the lower cover 5 of the box core mold on the longitudinal or transverse sides of the box core mold, so as to limit the horizontal offset of the box core mold; the leg 3 is arranged at the bottom of the support part 1 and used for being fixed with the bottom formwork.

[0040] Therefore, the special support can replace the cushion block (or horse stool) in the traditional scheme to position the combined grid, specifically, the special support can support the box core mold through the support part 1, and can limit the box core mold through the left limiting part and the right limiting part while supporting, cooperate with the traditional pressing top steel bar to limit the displacement of the box core mold in the transverse (horizontal) and longitudinal (vertical) directions respectively, ensure the installation position accuracy of the box core mold, ensure the control of the thickness of the upper and lower flange cast-in-place layer, ensure the uniformity of the cast-in-place layer concrete thickness, ensure the uniformity of the ribbed beam I-shaped section, solve the problems of box core mold deviation and floating in the original construction process.

[0041] Specifically, in the embodiment, the left limiting part and the right limiting part are structurally identical, and each includes a side wall 201 and a top wall 202; the bottom of the side wall 201 is fixedly connected to the top of the support part 1, and the top of the side wall 202 extends vertically upward relative to the bottom of the support part 1; one end of the top wall 202 is fixedly connected to the top of the side wall 201, and the other end extends horizontally to the middle of the support part 1, so that the top wall 202 and the side wall 201 form a hook-shaped limiting structure; the box core mold is limited between the side walls 201 of the left limiting part and the right limiting part.

[0042] Therefore, the edge opening of the box core mold (i.e. the extension part 6 formed by the upper cover 4 and the lower cover 5 of the box core mold) can pass into the hook of the special support, limiting the displacement of the core mold, and the top wall 202 can also play a role in resisting floating, and cooperating with the pressing bar steel bar, the purpose of controlling the installation accuracy of the position of the box core mold and resisting floating is achieved. Moreover, the two side hooks limit the deflection of the box core mold around the pressing bar steel bar. Furthermore, since the two side hooks have a certain spacing, after one side of the box core mold is placed into the support, the box core mold is translated to pass the other side into the hook of the support, thereby completing the assembly of the support and the box core mold. The special support is simple to position and install, and fast to install.

[0043] More specifically, in the embodiment, the bottom of the support leg 3 is provided with a fastening part 301 with a screw hole 302; the special support is fixed with the bottom formwork through the screw passing through the screw hole 301. Therefore, since the size of the box core mold and the spacing between the ribbed beams are matched during construction, only the distance between the hook and the ribbed beam or the framework beam stirrup is measured, and the special support can be fixed by screwing, without the need for line laying to ensure the installation position of the box core mold between the ribbed beams. The special support has a simple structure, is simple to install, and can achieve good fixing effect only by screwing, is fast to install, and improves the on-site installation quality and construction efficiency.

[0044] Further, in the embodiment, the support leg 3 is fixed to the bottom of the support part 1 by welding. Moreover, the support part 1, the left limiting part and the right limiting part can be made of 3mm thick hot-rolled steel plate punched.

[0045] The size of the special support can be matched with the size of the box core mold, for example, referring to Figures 2-5 The distance between the side wall 202 of the left limiting part and the side wall 202 of the right limiting part of the special support can be 460 mm, the total length is 466 mm, the two ends of the support part 1 are provided with a hook with a clearance of 15 mm, and three supporting legs 3 are arranged at the lower part, and the bottom surface of the supporting leg 3 is provided with a φ6 screw hole 302.

[0046] For example, in order to achieve Figure 6 The requirements of four 500*450 series box core mold combinations in the middle, the box core mold with a length of 500 mm, a width of 450 mm and a height of 115 mm can be used in the project Figure 7 , Figure 8 The box core mold with a length of 500 mm, a width of 450 mm and a height of 115 mm, Figure 9 , Figure 10 The box core mold with a length of 500 mm, a width of 450 mm and a height of 260 mm, or other specifications of box core mold can also be selected, and the specific specifications of the box core mold can be selected according to the thickness requirements of the upper flange and the lower flange of the hollow floor. In order to simplify the installation process and improve the construction efficiency, referring to Figures 7-10 The special support can be arranged on the side with a width of 450 mm, so that only one type of support can meet the requirements of the project, and the material cost and installation difficulty are reduced. It should be noted that Figure 7 , Figure 8 The size parameters of the special support used for the box core mold with a length of 500 mm, a width of 450 mm and a height of 115 mm shown in Figure 9 , Figure 10 The size parameters of the special support used for the box core mold with a length of 500 mm, a width of 450 mm and a height of 260 mm shown in Figure 7 , Figure 8 The height of the extension part 6 of the box core mold with a length of 500 mm, a width of 450 mm and a height of 115 mm shown in Figure 9 , Figure 10 The height of the extension part 6 of the box core mold with a length of 500 mm, a width of 450 mm and a height of 260 mm shown in. The structure of the special support provided by the utility model can be used for positioning of various types of box core molds, and the specific size parameters of the special support can be matched and designed according to the type of the box core mold.

[0047] Specifically, by using the civil field structure simulation analysis software midas FEA NX simulation test, when the box core mold is offset by more than the specification requirement by using the traditional cushion block (or horse stool), the hollow floor stress distribution diagram is as shown in Figure 11 When the core mold offset is within the specification requirement by using the special support (the support specially used for positioning of the core mold in the combined grid cast-in-place concrete hollow floor), the hollow floor stress distribution diagram is as shown in Figure 12 .

[0048] To sum up, the above is only the preferred embodiment of the present application, and is not used to limit the protection scope of the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A combined grid cast-in-situ concrete hollow floor special support, characterized in that, The special support is provided with a supporting part, a left limiting part, a right limiting part and a supporting leg; The supporting part is horizontally arranged and used for supporting the box core mold; The left limiting part and the right limiting part are respectively arranged on the left side and the right side of the supporting part and used for limiting the extension part formed by the upper cover and the lower cover of the box core mold on the left side or the right side of the box core mold in the longitudinal direction or the transverse direction, so as to limit the horizontal deviation of the box core mold; The supporting leg is arranged at the bottom of the supporting part and used for being fixed with the bottom mold plate.

2. The combined grid cast-in-situ concrete hollow floor special support according to claim 1, characterized in that, The left limiting part and the right limiting part are the same in structure and each include a side wall and a top wall; The bottom of the side wall is fixedly connected with the top of the supporting part, and the top of the side wall vertically extends upward relative to the bottom of the supporting part; One end of the top wall is fixedly connected with the top of the side wall, and the other end horizontally extends to the middle part of the supporting part, so that the top wall and the side wall form a hook-shaped limiting structure; The box core mold is limited between the side wall of the left limiting part and the side wall of the right limiting part.

3. The combined grid cast-in-situ concrete hollow floor special support according to claim 2, characterized in that, The bottom of the supporting leg is provided with a fastening part with a screw hole; The special support and the bottom mold plate are fixed through the screw passing through the screw hole.

4. The combined grid cast-in-situ concrete hollow floor special support according to claim 1, characterized in that, The supporting leg is fixed to the bottom of the supporting part by welding.

5. The combined grid cast-in-situ concrete hollow floor special support according to claim 2, characterized in that, The distance between the side wall of the left limiting part and the side wall of the right limiting part is 460 mm.

6. The combined grid cast-in-situ concrete hollow floor special support according to any one of claims 1-5, characterized in that, The supporting part, the left limiting part and the right limiting part are made of hot-rolled steel plate stamping.

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