A close joint connection structure of a two-way composite plate and its construction method

Abstract

The present invention discloses a close-jointed connection structure of a two-way composite slab and a construction method thereof, comprising a concrete precast slab, a grooved concrete precast slab, and a cast-in-place concrete layer, wherein the grooved concrete precast slab is connected between two concrete precast slabs, and the cast-in-place concrete layer is cast on the concrete precast slab and the grooved concrete precast slab. Beneficial effects of the present invention: The present invention uses grooved concrete precast slabs to replace the post-cast slab strips of the integral joints in the connection of the bottom plate of the two-way composite slab, which does not require the provision of a bottom formwork, reduces the use of vertical poles, and does not require the provision of additional steel bars, which can save scaffolding and formwork during construction; has good force-bearing performance; is simple and convenient to operate, the grooving of the precast slab is completed in the factory, and on site, it is only necessary to splice the concrete precast slab and the grooved concrete precast slab together, and connect the steel bars in the strip grooves, which is economical and practical.

Description

Technical Field

[0001] The present invention relates to the technical field of prefabricated building engineering, and in particular to a close-jointed connection structure of a bidirectional composite plate and a construction method thereof. Background Art

[0002] Concrete composite slab is a type of floor structure that combines precast concrete slabs with cast-in-place layers. It has the advantages of fast construction and saving formwork. Since the bottom of the composite slab is made up of several precast concrete slabs, the joints are the weakest points of the composite slab. Therefore, the node connection structure at the joints is crucial to the force transmission of the composite slab.

[0003] According to Article 6.6.3 of the Technical Code for Prefabricated Concrete Structures (JGJ1-2014), integral joints can be used when the composite slab is designed as a two-way slab; Article 6.6.6 stipulates that integral joints can be in the form of post-cast strips. The longitudinal force-bearing steel bars on the side of the concrete precast slab must be extended into the post-cast strip for welding, lap connection, bending and anchoring. The width of the post-cast strip should not be less than 200mm. Figure 1 As shown, however, in engineering applications, the joints of the post-cast slab (300mm wide) are generally supported by 400mm wide formwork, and the bottom support of the formwork is set up with a traditional socket-type wheel buckle or disc buckle scaffolding. A vertical pole is set just below the post-cast slab, and an adjustable top support is set up on the top of the vertical pole using a fastener connection to support the formwork. This bottom formwork usually has a small rigidity. When pouring concrete, it is easy to cause the lower edge of the post-cast slab to warp, resulting in quality problems such as slab leakage and misalignment, which seriously affects the visual quality and flatness of the top plate. After the formwork is removed in the later stage, the quality problems such as slab leakage and misalignment need to be manually polished and repaired. The workload of polishing and repairing is large, and a large number of scaffolding must be removed, which consumes additional construction costs.

[0004] The "Construction of Prefabricated Concrete Connection Nodes" (15G310-1) supplements the close joint structure of the two-way composite slab, such as Figure 2 As shown in the figure, this structure simply applies the separated joints used in one-way composite plates directly to two-way composite plates, but it brings new problems: (1) The stress characteristics of two-way composite plates are different from those of one-way composite plates. If close-jointed joints are used directly, the additional longitudinal reinforcement at the joints is too high, and the amount of additional reinforcement must be increased; (2) In order to prevent cracks from developing too quickly at the joints, other structural measures must be added at the joints, which will increase material consumption and cost.

[0005] 1. For example, a Chinese patent discloses a bidirectional composite slab bottom plate with prestressed joints (application number: CN201920063822.2). The connection of the bidirectional composite slab bottom plate adopts joint connection. A post-cast groove is left at a certain distance at the joint connection. The end of the connecting steel bar is exposed in the post-cast groove. The end should be threaded in advance. After the bidirectional composite slab bottom plate is manufactured in the factory, transported to the site and hoisted into place, the grooves of the two composite slab bottom plates to be connected by the joint are aligned, and the connecting steel bars in the grooves are also aligned. A steel bar connector with a prestressing function is placed in the groove. While connecting the steel bars, a tensile force is applied to the steel bars. This tensile force will generate prestress in the concrete at the joint. The prestress can ensure that the joint remains under pressure during the later use process and avoid cracking of the joint. The connecting steel bars and the distribution steel bars on the joint are both force-bearing steel bars of the bidirectional composite slab bottom plate, and together with the post-cast concrete, form a bidirectional composite slab that can withstand loads.

[0006] 2. For example, a Chinese patent discloses a two-way composite slab connection structure that does not require a hanging formwork (application number: CN202222028646.3), including: a steel base plate, bolts, a precast concrete base plate of a composite slab, and a cast-in-place concrete layer of a composite slab, wherein the precast concrete base plate of the composite slab is arranged on the steel base plate, the cast-in-place concrete layer of the composite slab is arranged on the precast concrete base plate of the composite slab, and the bolts are buried in the precast concrete base plate of the composite slab and inserted on the steel base plate. The two-way composite slab connection structure that does not require a hanging formwork provided in this application has a simple structure and is easy to construct. The hanging formwork construction at the joints can be eliminated, which saves construction time and reduces construction procedures. The joint width only needs to meet the construction operation requirements, thereby reducing the joint width of the two-way composite slab.

[0007] In summary, the connection structure of the two-way composite slab in the current specifications and drawings is complex in construction technology, consumes a lot of formwork and support poles, and requires additional steel bars. Simplifying the connection structure of the two-way composite slab without increasing the amount of steel bars is the key to the application and promotion of composite slabs. If the above problems can be completely solved, it will definitely speed up the construction speed, reduce the cost, improve the visual quality and performance of the building, and be conducive to the promotion and implementation of building industrialization.

[0008] Therefore, it is necessary to propose a close-jointed connection structure of a two-way composite plate and a construction method thereof for the above-mentioned problem. Summary of the invention

[0009] In view of the above-mentioned deficiencies in the prior art, the object of the present invention is to provide a close-jointed connection structure of a bidirectional composite plate and a construction method thereof, so as to solve the above-mentioned problems.

[0010] A close-jointed connection structure of a bidirectional composite slab comprises a concrete precast slab, a grooved concrete precast slab and a cast-in-place concrete layer. The grooved concrete precast slab is connected between two concrete precast slabs, and the cast-in-place concrete layer is cast on the concrete precast slab and the grooved concrete precast slab.

[0011] Preferably, the steel bars in the precast concrete panel are extended with beard bars at the panel ends connected to the precast concrete panel with grooves.

[0012] Preferably, a first slab bottom longitudinal reinforcement is reserved at the slab end where the precast concrete slab is directly connected to the beam.

[0013] Preferably, the panel surface of the precast concrete panel is provided with a first truss steel bar.

[0014] Preferably, the panel surface of the grooved precast concrete panel is provided with strip-shaped grooves.

[0015] Preferably, the position of the strip groove on the grooved precast concrete panel surface corresponds to the position of the ribs at the ends of the precast concrete panel, and the width and depth of the strip groove can accommodate the ribs.

[0016] Preferably, a second bottom longitudinal reinforcement is reserved at the end of the grooved precast concrete slab directly connected to the beam.

[0017] Preferably, the panel surface of the grooved precast concrete panel is provided with a second truss steel bar.

[0018] A method for closely splicing and connecting bidirectional laminated plates, the method comprising the following steps:

[0019] S1. Production of precast concrete panels and precast concrete panels with grooves;

[0020] S2. Hoist the precast panels, and place the concrete precast panels and the grooved concrete precast panels at intervals, so that the beard ribs and the strip grooves are aligned at the joints;

[0021] S3, placing the beard bars on both sides of the concrete precast slab in the strip grooves for overlap connection or welding connection, and anchoring the first slab bottom longitudinal bars and the second slab bottom longitudinal bars into the beam;

[0022] S4. Tie and install the stress reinforcement in the cast-in-place concrete layer;

[0023] S5. Concrete is cast in situ on the concrete precast panels, the concrete precast panels with grooves, the inside of the strip grooves, and the joints between the concrete precast panels and the concrete precast panels with grooves, so that the cast-in-situ concrete layer is tightly combined with the precast panels to form a bidirectional force-bearing concrete composite slab.

[0024] Preferably, the length of the beard rib needs to satisfy its overlap in the strip groove.

[0025] Compared with the prior art, the present invention has the following beneficial effects: the present invention uses grooved concrete precast panels to replace the currently commonly used integral joint post-cast slab strips in the connection of the bottom plates of the two-way composite slabs, so there is no need to set up a bottom formwork, reduce the use of vertical poles, and also do not need to set up additional steel bars, which can save a lot of scaffolding and formwork during on-site construction; the present invention is consistent with the force transmission path and principle of the integral joint connection structure using the post-cast slab strip, the structure and force transmission at the joint are continuous, and it has good force-bearing performance; the present invention is simple to operate and convenient to construct, the grooving work of the precast panels is all completed in the factory, and on-site only needs to splice the concrete precast panels and the grooved concrete precast panels together as required, and connect the steel bars in the strip grooves, which is economical, practical and easy to implement. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A schematic diagram of an integral joint in the form of a post-cast strip in the prior art;

[0027] Figure 2 A schematic diagram of a conventional overlapping surface with additional steel bar-type close-jointed seams;

[0028] Figure 3 It is a structural diagram of the close-jointed joint of the bidirectional laminated plate of the present invention;

[0029] Figure 4 It is a schematic diagram of the prefabricated panel connection structure of the present invention;

[0030] Figure 5 yes Figure 4 Schematic side view of

[0031] Figure 6 yes Figure 4 A top view of

[0032] Figure 7 It is a structural diagram of a precast concrete panel of the present invention;

[0033] Figure 8 It is a side structural diagram of a precast concrete panel of the present invention;

[0034] Fig. 9 is a top view of a precast concrete panel of the present invention;

[0035] Fig.10 This is a structural diagram of a grooved concrete prefabricated panel of the present invention;

[0036] Fig.11 This is a side structural diagram of a grooved prefabricated concrete panel of the present invention;

[0037] Fig.12 This is a top view of the structure of the grooved prefabricated concrete panel of the present invention;

[0038] Fig.13 It is a flow chart of the construction method of the present invention.

[0039] Reference numerals in the figure: 1. precast concrete slab; 2. precast concrete slab with grooves; 3. cast-in-place concrete layer; 101. beard reinforcement; 102. first slab bottom longitudinal reinforcement; 103. first truss reinforcement; 201. strip groove; 202. second slab bottom longitudinal reinforcement; 203. second truss reinforcement; 301. force-bearing reinforcement. DETAILED DESCRIPTION

[0040] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0041] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and the like are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", and the like may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0042] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0043] The embodiments of the present invention are described in detail below with reference to the accompanying drawings, but the present invention can be implemented in many different ways as defined and covered by the claims.

[0044] like Figure 3 Combined with Figures 4 to 13As shown, a close-jointed connection structure of a bidirectional composite slab comprises a precast concrete slab 1, a precast concrete slab 2 with grooves, and a cast-in-place concrete layer 3. The precast concrete slab 2 with grooves is connected between two precast concrete slabs 1, and the cast-in-place concrete layer 3 is cast on the precast concrete slab 1 and the precast concrete slab 2 with grooves.

[0045] Furthermore, the steel bars in the precast concrete panel 1 are extended with beard bars 101 at the panel ends connected to the precast concrete panel 2 with grooves.

[0046] Furthermore, a first slab bottom longitudinal reinforcement 102 is reserved at the slab end where the concrete precast slab 1 is directly connected to the beam.

[0047] The further technical solution has the beneficial effect that the first slab bottom longitudinal reinforcement 102 can be anchored into the beam to enhance the firmness of the composite slab.

[0048] Furthermore, the surface of the precast concrete panel 1 is provided with a first truss steel bar 103 .

[0049] The further technical solution has the beneficial effect that the first truss reinforcement 103 can improve the connection strength between the prefabricated slab and the cast-in-place layer.

[0050] Furthermore, the panel surface of the grooved prefabricated concrete panel 2 is provided with strip-shaped grooves 201 .

[0051] The further technical solution has the beneficial effect that the strip groove 201 can provide space for the overlap of the beard reinforcement and can also improve the connection strength between the prefabricated board and the cast-in-place layer.

[0052] Furthermore, the position of the strip groove 201 on the surface of the grooved precast concrete panel 2 corresponds to the position of the beard rib 101 at the end of the concrete precast panel 1, and the width and depth of the strip groove 201 can accommodate the beard rib 101.

[0053] Furthermore, the second bottom longitudinal reinforcement 202 is reserved at the end of the grooved concrete prefabricated panel 2 directly connected to the beam.

[0054] The further technical solution has the beneficial effect that the second bottom longitudinal reinforcement 202 can be anchored into the beam to enhance the firmness of the composite slab.

[0055] Furthermore, the panel surface of the grooved precast concrete panel 2 is provided with a second truss steel bar 203 .

[0056] The beneficial effect of adopting a further technical solution is that the second truss reinforcement 203 can improve the connection strength between the prefabricated plate and the cast-in-place layer.

[0057] A method for closely splicing and connecting bidirectional laminated plates, the method comprising the following steps:

[0058] S1, producing a precast concrete panel 1 and a precast concrete panel 2 with grooves;

[0059] S2, hoisting the precast panels, placing the concrete precast panel 1 and the grooved concrete precast panel 2 at intervals, so that the beard ribs 101 and the strip grooves 201 are aligned at the joints;

[0060] S3, placing the beard bars 101 on both sides of the precast concrete slab 1 in the strip grooves 201 for overlap connection or welding connection, and anchoring the first slab bottom longitudinal bars 102 and the second slab bottom longitudinal bars 202 into the beam;

[0061] S4, tying and installing the stress reinforcement 301 in the cast-in-place concrete layer 3;

[0062] S5, cast concrete in situ on the concrete precast panel 1, the grooved concrete precast panel 2, the inside of the strip groove 201 and the joints between the concrete precast panel 1 and the grooved concrete precast panel 2, so that the cast-in-situ concrete layer 3 is tightly combined with the precast panel to form a bidirectional force-bearing concrete composite panel.

[0063] Furthermore, the length of the beard rib 101 needs to satisfy its overlap in the strip groove 201 .

[0064] Compared with the prior art, the present invention has the following beneficial effects: the present invention uses a grooved concrete precast panel 2 to replace the currently commonly used integral joint post-cast panel strip in the connection of the bottom plate of the bidirectional composite panel. This method does not need to set a bottom mold, reduces the use of vertical poles, and does not need to set additional steel bars. A large amount of scaffolding and templates can be saved during on-site construction; the present invention is consistent with the force transmission path and principle of the integral joint connection structure using the post-cast panel strip, the structure and force transmission at the joint are continuous, and it has good force-bearing performance; the present invention is simple to operate and convenient to construct. The grooving work of the precast panel 1 is all completed in the factory. On site, it is only necessary to splice the concrete precast panel 1 and the grooved concrete precast panel 2 together as required, and connect the steel bars in the strip groove 201. It is economical, practical, and easy to implement.

[0065] Working principle:

[0066] Step 1, producing a precast concrete panel 1 and a precast concrete panel with grooves 2;

[0067] Step 2: hoist the precast panels, place the concrete precast panels 1 and the grooved concrete precast panels 2 at intervals, and align the beard ribs 101 with the strip grooves 201 at the joints;

[0068] Step 3: Place the beard bars 101 on both sides of the precast concrete slab 1 in the strip grooves 201 for overlap connection or welding connection, and anchor the first slab bottom longitudinal bars 102 and the second slab bottom longitudinal bars 202 into the beam;

[0069] Step 4: Tie and install the stress reinforcement 301 in the cast-in-place concrete layer 3;

[0070] Step 5: Cast concrete in situ on the concrete precast panel 1, the grooved concrete precast panel 2, the inside of the strip groove 201, and the joints between the concrete precast panel 1 and the grooved concrete precast panel 2, so that the cast-in-situ concrete layer 3 is tightly combined with the precast panel to form a bidirectional force-bearing concrete composite panel.

[0071] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A close-jointed joint structure of a two-way laminated plate, characterized in that: It comprises a precast concrete panel (1), a precast concrete panel with grooves (2), and a cast-in-place concrete layer (3), wherein the precast concrete panel with grooves (2) is connected between two precast concrete panels (1), and the cast-in-place concrete layer (3) is cast on the precast concrete panel (1) and the precast concrete panel with grooves (2); The steel bars in the concrete precast panel (1) extend with beard bars (101) at the panel end connected to the grooved concrete precast panel (2); the first panel bottom longitudinal bars (102) are reserved at the panel end where the concrete precast panel (1) is directly connected to the beam; the panel surface of the concrete precast panel (1) is provided with a first truss steel bar (103); the panel surface of the grooved concrete precast panel (2) is provided with a strip groove (201); the position of the strip groove (201) on the panel surface of the grooved concrete precast panel (2) corresponds to the position of the beard bars (101) at the panel end of the concrete precast panel (1), and the width and depth of the strip groove (201) can accommodate the beard bars (101); the second panel bottom longitudinal bars (202) are reserved at the panel end where the grooved concrete precast panel (2) is directly connected to the beam; the panel surface of the grooved concrete precast panel (2) is provided with a second truss steel bar (203); It also includes a construction method, the method steps of which are: S1, producing a precast concrete panel (1) and a precast concrete panel with grooves (2); S2, hoisting the precast panels, placing the concrete precast panels (1) and the grooved concrete precast panels (2) at intervals, so that the beard ribs (101) and the strip grooves (201) are aligned at the joints; S3, placing the beard bars (101) on both sides of the concrete precast slab (1) in the strip grooves (201) for overlap connection or welding connection, and anchoring the first slab bottom longitudinal bars (102) and the second slab bottom longitudinal bars (202) into the beam; S4, tying and installing the stress-bearing steel bars in the cast-in-place concrete layer (3); S5, pouring concrete in situ on the concrete precast panel (1), the grooved concrete precast panel (2), the interior of the strip groove (201), and the joints between the concrete precast panel (1) and the grooved concrete precast panel (2), so that the cast-in-situ concrete layer (3) is tightly combined with the precast panel to form a bidirectional force-bearing concrete composite panel; The length of the beard rib (101) needs to be sufficient to allow it to overlap in the strip groove (201).

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