A kind of assembled cast-in-place concrete composite beam and construction method thereof

Abstract

The present invention belongs to the technical field of concrete composite beams, and specifically relates to an assembled cast-in-place concrete composite beam and a construction method thereof, wherein the concrete composite beam comprises a plurality of steel bar bundling cages and a prefabricated plate located outside the steel bar bundling cage, wherein the prefabricated plates each comprise three integrated concavely distributed concrete plates, wherein an internal reinforcement skeleton and a pulling member fixedly connected to the internal reinforcement skeleton are provided inside the concrete plates, and the two ends of the internal reinforcement skeleton extend out of the concrete plates respectively; the method adopts steps S1 to S6, and while closing the gap at the connection node, each prefabricated plate is firmly grasped, and the portion to be welded is significantly reduced, especially compared with the traditional method of overlapping multiple steel bars, each connection node only needs to weld two connection seams. The present invention can use a concave support member to cross the connection nodes of each prefabricated plate when loaded, and the support surface acting on the connection node of the prefabricated plate is larger, so as to improve the shear resistance of the connection node of each prefabricated part.

Description

Technical Field

[0001] The invention belongs to the technical field of concrete composite beams, and in particular relates to an assembled cast-in-place concrete composite beam and a construction method thereof. Background Art

[0002] Prefabricated cast-in-place concrete composite beams refer to beam structures that are formed by combining prefabricated concrete components (such as beam sections, slabs, etc.) with concrete poured on site to form an integrally stressed beam structure. In commercial housing construction, the span of concrete composite beams can reach 4 to 5 meters; while for some factory buildings, the span of concrete composite beams is even greater. The integrated prefabricated parts required for this are relatively long and inconvenient to transfer. They are generally prefabricated in several small sections and then assembled together on site.

[0003] Small prefabricated parts are made by first building a formwork in the factory, laying a steel frame, pouring concrete, and then demolding after hardening. According to the plan of the construction site, a certain number of small prefabricated parts are transported to the construction site in advance by vehicles.

[0004] When pouring existing building concrete beams, the prefabricated parts are connected end to end, and the prefabricated parts are supported from below by formwork and steel frames to form a long beam shell, which is then poured.

[0005] However, the prefabricated cast-in-place beam has a large span and a high load, and there are gaps in the connection nodes of the prefabricated parts, which makes these gaps subject to longitudinal brittle shear after bearing the load. Generally, a steel structure is selected to strengthen the connection nodes of the prefabricated parts. The support surface of the steel structure for the prefabricated parts is limited, which is not conducive to improving the shear resistance of the connection nodes of each prefabricated part. Summary of the invention

[0006] The purpose of the present invention is to provide an assembled cast-in-place concrete composite beam and a construction method thereof, which can use concave support members to cross the connection nodes of each prefabricated panel when loaded, so that the support surface acting on the connection nodes of the prefabricated panels is larger, thereby improving the shear resistance of the connection nodes of each prefabricated component.

[0007] The technical solution adopted by the present invention is as follows:

[0008] An assembled cast-in-place concrete composite beam comprises a plurality of steel bar bundling cages and prefabricated panels located outside the steel bar bundling cages, wherein the prefabricated panels each comprise three integrated concavely distributed concrete panels, wherein an internal reinforcement skeleton and a pulling member fixedly connected to the internal reinforcement skeleton are arranged inside the concrete panels, and concrete panels are extended from both ends of the internal reinforcement skeleton, wherein a plurality of longitudinal convex strips are integratedly installed on one side of two parallel concrete panels close to each other, and a plurality of transverse convex strips are integratedly installed on the upper surface of the other concrete panel.

[0009] A concave support member is arranged between the ends of two adjacent prefabricated panels that are close to each other, and a first corrugated portion and a second corrugated portion are arranged at both ends of the concave support member. A plurality of vertical slots are spaced apart on the lower surface of the first corrugated portion, and a plurality of horizontal slots are spaced apart on the lower surface of the second corrugated portion.

[0010] The concave support member includes a horizontal steel plate and two vertical steel plates respectively fixed on both sides of the horizontal steel plate. The lower surface of the horizontal steel plate is closely attached to the upper surface of the adjacent concrete slab, and one side of the vertical steel plate is closely attached to one side of the adjacent concrete slab. The first corrugated portion is integrally installed at the end of the horizontal steel plate, and the second corrugated portion is integrally installed at the end of the vertical steel plate.

[0011] The pulling member comprises a vertical rod and a horizontal rod embedded in the concrete slab, one end of the vertical rod and one end of the horizontal rod are fixedly connected to the inner reinforcement frame, the other end of the vertical rod passes through the vertical slot, and the other end of the horizontal rod passes through the horizontal slot.

[0012] Before construction, prepare enough thick and thin steel bars in the factory, bend and bundle them into several internal reinforcement skeletons, then weld a specified number of vertical and horizontal bars to the internal reinforcement skeletons respectively, put them into the formwork and pour concrete, so that the internal reinforcement skeleton with vertical and horizontal bars is embedded in the concrete slab, the vertical and horizontal bars are partially extended, and several vertical slots are cut in the horizontal steel plate, and several horizontal slots are cut in the vertical steel plate, and then transported to the construction site by engineering vehicles for use.

[0013] Before pouring, scaffolding and formwork are built in sequence under the concrete composite beam to be constructed, and a specified number of precast panels are placed into the formwork one by one along the axial direction and connected together. The fine steel bars belonging to the internal reinforcement skeleton are staggered and then tied and fixed with wire. The positions at both ends of the concrete composite beam are tied and fixed with the supporting steel bars to complete the assembly.

[0014] When preparing for pouring, first stick the horizontal steel plate and the vertical steel plate in turn with mortar on the inner side of the concave concrete slab. The front and back depressions of the first waveform are used to cover the vertical rod and the horizontal convex strip respectively, and the front and back depressions of the second waveform are used to cover the horizontal rod and the longitudinal convex strip respectively. The inner reinforcement skeleton is inserted into the front depression of the first waveform and the front depression of the second waveform, and then the connection seams of the horizontal steel plate and the vertical steel plate are welded. After the connection seams in the entire beam are welded, start spraying concrete with a pump truck, and use an inserted concrete vibrator at the same time. The high-frequency vibration waves generated will propagate into the concrete, rearrange the concrete particles and tightly combine them, and discharge the bubbles and excess water in them. This process helps to reduce the porosity inside the concrete, improve the density and strength of the concrete, and demold the concrete after it dries and hardens.

[0015] When loaded, the internal reinforcement skeleton, concave support members and pulling members span the connection nodes of each prefabricated panel, and the support surface acting on the connection nodes of the prefabricated panels is larger to improve the shear resistance of the connection nodes of each prefabricated component. In this process, horizontal steel plates and vertical rods are used to resist the horizontal shear effect, and vertical steel plates and horizontal rods are used to resist the vertical shear effect. At the same time, the vertical rods and horizontal rods tighten the internal reinforcement skeleton, thereby closing the gaps at the connection nodes and grasping each prefabricated panel. Compared with the traditional method of support through steel bars, the support surface acting on the connection nodes of the prefabricated panels is larger to improve the shear resistance of the connection nodes of each prefabricated component.

[0016] The side of the horizontal steel plate close to the concrete slab is provided with a plurality of first grooves at intervals, and the lower surface of the vertical steel plate is provided with a plurality of second grooves at intervals. When applying mortar, the first grooves and the second grooves are respectively used to accommodate mortar, and as much mortar as possible is added between the gaps between the horizontal and vertical steel plates and the concrete slab, so that the horizontal and vertical steel plates are more firmly bonded and not easy to fall off.

[0017] Both ends of the prefabricated board are provided with step grooves with concave structures, and the inner walls of the step grooves are coated with waterproof coatings. Before installing the horizontal steel plates and the vertical steel plates, each step groove can be grinded on the prefabricated board by a grinder in the factory, and then the step grooves are covered with waterproof coatings, so that the horizontal steel plates and the vertical steel plates form concave support members that stick to the waterproof coatings, which can improve the waterproof performance of the connection nodes while providing support and anti-shear effects.

[0018] A high-strength plastic plate with a concave structure is inserted inside the step groove. The high-strength plastic plate covers adjacent horizontal steel plates and vertical steel plates from the outside. The high-strength plastic plate partially extends out of the step groove. The high-strength plastic plate is used to connect two adjacent step grooves. After applying a waterproof coating, mortar can be applied at the construction site, and the high-strength plastic plate can be placed in it for bonding. The thickness of the concrete beam is compensated in the step groove, and the horizontal steel plate and the vertical steel plate are combined to form a concave support member that spans the connection nodes of each prefabricated plate, thereby increasing the supporting strength of the concave support member.

[0019] A vertical thread is provided in the middle of the upper surface of the vertical rod, and the vertical rod is connected with a vertical fastener for pressing the horizontal steel plate through the vertical thread.

[0020] A horizontal thread is provided in the middle of one end of the horizontal rod, and the horizontal rod is connected with a horizontal fastener for pressing the vertical steel plate through the horizontal thread.

[0021] The transverse steel plates are replaced by transverse steel bars, and at least two longitudinal steel kits are arranged outside the transverse steel bars. One end of the longitudinal steel kit is annularly sleeved outside the transverse steel bars, and the other end of the longitudinal steel kit is rod-shaped and embedded in adjacent concrete slabs and fixedly connected to the internal reinforcement skeleton. The transverse steel plates that need to be welded are removed, and the transverse steel bars are used in conjunction with the longitudinal steel kits to tighten the two adjacent internal reinforcement skeletons, which can still span the connection nodes of each prefabricated plate. The transverse steel bars and the longitudinal steel kits are used to resist the transverse shearing effect, which ensures sufficient support strength and further simplifies the construction steps.

[0022] The vertical steel plates are replaced by longitudinal steel bars, and at least two transverse steel kits are arranged outside the longitudinal steel bars. One end of the transverse steel kit is annularly sleeved outside the longitudinal steel bars, and the other end of the transverse steel kit is rod-shaped and embedded in adjacent concrete slabs and fixedly connected to the internal reinforcement skeleton. The vertical steel plates that need to be welded are eliminated, and the longitudinal steel bars are used in combination with the transverse steel kit to tighten the two adjacent internal reinforcement skeletons, which can still span the connection nodes of each prefabricated plate. The longitudinal steel bars and the transverse steel kit are used to resist the vertical shearing effect, which ensures sufficient support strength and further simplifies the construction steps.

[0023] Both ends of the transverse steel bars and both ends of the longitudinal steel bars are of a hole structure, and a first annular pin and a second annular pin are respectively inserted through the holes. After the transverse steel bars and the longitudinal steel bars are installed, the first annular pin and the second annular pin are respectively installed, and the longitudinal steel kit and the transverse steel kit are used to limit the position to prevent the transverse steel bars and the longitudinal steel bars from falling off, so that the transverse steel bars and the longitudinal steel bars do not need to be welded and fixed, but can be locked at each connection node. In addition, the materials are simple to obtain and can be directly buried in the concrete without obstructing the steel bar bundling cage placed therein.

[0024] A method for constructing an assembled cast-in-place concrete composite beam comprises the following steps:

[0025] S1. Prefabricated accessories: The coarse and fine steel bars in the factory are bent and bundled into several internal reinforcement skeletons to make the base skeleton;

[0026] S2. Pre-installation of the plant: Place the prefabricated inner reinforcement skeleton into the hollow concave formwork and pour concrete so that the base skeleton part extends out of the concrete slab;

[0027] S3. Site preparation: Build scaffolding and formwork, place the specified number of prefabricated panels one by one in the formwork along the axial direction and connect them together, first cover the step groove with a waterproof coating, then use mortar to glue the high-strength plastic sheet, make concave support members to connect two adjacent base frames, span the connection nodes of each prefabricated panel, and resist the shearing effect;

[0028] S4, on-site processing: After the concave support members and the base frame of the entire beam are connected, the steel bar bundling cages are placed one by one, and two adjacent steel bar bundling cages are tied and fixed with wire to complete the assembly;

[0029] S5, pouring: Use a pump truck to spray concrete, and use an inserted concrete vibrator at the same time, the high-frequency vibration waves generated will propagate into the concrete;

[0030] S6. Demoulding: If the concrete beam is cast on the main beam frame of the building, wait at least 4 to 5 days before demolding; or if the concrete beam is cast on the roof, wait at least 5 days before demolding.

[0031] The technical effects achieved by the present invention are:

[0032] Before the construction of the present invention, an internal reinforcement skeleton with vertical bars and cross bars is embedded in the concrete slab, and the horizontal steel plates and vertical steel plates are adhered in turn on the inner side of the concave concrete slab, and then the connecting seams of the horizontal steel plates and the vertical steel plates are welded; when loaded, the horizontal steel plates and the vertical steel plates form a concave support member that spans the connecting nodes of each prefabricated slab, so that the horizontal steel plates and the vertical steel plates not only span the connecting nodes of each prefabricated slab, but also can use their wavy parts to firmly tighten the steel bar bundling cage and the internal reinforcement skeleton, and can leave space for the concrete to wrap the vertical bars and cross bars as much as possible, and use the horizontal steel plates and vertical bars to resist the lateral shearing effect, and use the vertical steel plates and cross bars to resist the vertical shearing effect, and at the same time, the vertical bars and cross bars tighten the internal reinforcement skeleton, so as to close the gaps at the connecting nodes and hold each prefabricated slab firmly. Compared with the traditional support method through steel bars, the support surface acting on the connecting nodes of the prefabricated slabs is larger, so as to improve the shear resistance of the connecting nodes of each prefabricated part.

[0033] The present invention utilizes transverse steel bars in conjunction with longitudinal steel sets to tighten two adjacent inner reinforcement skeletons, and utilizes longitudinal steel bars in conjunction with transverse steel sets to tighten two adjacent inner reinforcement skeletons, and can still span the connection nodes of each prefabricated panel, respectively resisting the transverse and vertical shearing effects, thereby ensuring sufficient supporting strength and further simplifying the construction steps.

[0034] The present invention adopts steps S1 to S6, through prefabricated accessories, factory preinstallation, on-site preparation, on-site processing, pouring and demoulding, to close the gaps at the connection nodes while holding each prefabricated panel firmly. Compared with the traditional support method through steel bars, the support surface acting on the connection nodes of the prefabricated panels is larger, so as to improve the shear resistance of the connection nodes of each prefabricated part. At the same time, the assembled cast-in-place concrete composite beam established through the above steps has significantly reduced parts that need to be welded, especially compared with the traditional method of overlapping multiple steel bars, each connection node only needs to weld two connection seams. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a front view of an assembled cast-in-place concrete composite beam in the first embodiment of the present invention;

[0036] Figure 2 It is a schematic diagram of the structure after a single prefabricated plate is assembled with a horizontal steel plate and a vertical steel plate in the first embodiment of the present invention;

[0037] Figure 3 It is a schematic diagram of the structure after a single prefabricated board and a high-strength plastic board are assembled in the first embodiment of the present invention;

[0038] Figure 4 is a top view of a concrete slab in Embodiment 1 of the present invention;

[0039] Figure 5 It is a front view of the inner rib skeleton in the first embodiment of the present invention;

[0040] Figure 6 is a bottom view of the assembled horizontal steel plate and vertical steel plate in the first embodiment of the present invention;

[0041] Figure 7 is an exploded view of a vertical rod and a vertical fastener in the first embodiment of the present invention;

[0042] Figure 8 It is a front view of a single prefabricated panel in the second embodiment of the present invention;

[0043] Fig. 9 It is a schematic diagram of the structure after a single prefabricated board and a high-strength plastic board are assembled in the second embodiment of the present invention;

[0044] Fig.10 It is a front view of a single transverse steel bar in the second embodiment of the present invention;

[0045] Fig.11 It is a front view of the inner rib skeleton in the second embodiment of the present invention;

[0046] Fig.12 It is a flow chart of a method for constructing an assembled cast-in-place concrete composite beam in Embodiment 3 of the present invention.

[0047] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0048] 1. Precast slab; 101. Concrete slab; 102. Internal reinforcement skeleton; 103. Longitudinal convex strip; 104. Horizontal convex strip; 2. Rebar bundling cage; 3. Horizontal steel plate; 301. First corrugated portion; 302. First groove; 4. Vertical steel plate; 401. Second corrugated portion; 402. Second groove; 5. Vertical slot; 6. Vertical rod; 7. Horizontal slot; 8. Horizontal rod; 9. Step groove; 10. Waterproof coating; 11. High-strength plastic plate; 12. Vertical fasteners; 13. Horizontal fasteners; 14. Horizontal reinforcement; 15. Longitudinal steel kit; 16. Longitudinal reinforcement; 17. Horizontal steel kit; 18. First annular pin; 19. Second annular pin. DETAILED DESCRIPTION

[0049] In order to make the purpose and advantages of the present invention more clearly understood, the present invention is specifically described below in conjunction with embodiments. It should be understood that the following text is only used to describe one or several specific embodiments of the present invention, and does not strictly limit the scope of protection of the specific claims of the present invention.

[0050] Embodiment 1:

[0051] like Figure 1-Figure 7 As shown, an assembled cast-in-place concrete composite beam includes a plurality of steel bar bundling cages 2 and a prefabricated panel 1 located outside the steel bar bundling cage 2, wherein the prefabricated panels 1 each include three integrated concavely distributed concrete panels 101, the concrete panels 101 may use C10-C70 concrete based on ordinary Portland cement, and in this embodiment, C40 concrete is preferably used, taking into account both excellent structural strength and low cost, an inner reinforcement skeleton 102 is provided inside the concrete panels 101, the inner reinforcement skeleton 102 includes a plurality of mutually parallel thick steel bars, and these thick steel bars are connected by concave thin steel bars, wherein the thick steel bars may use Grade III ribbed steel, and the thin steel bars may use Grade I steel, and the concrete panels 101 are extended from both ends of the inner reinforcement skeleton 102, wherein a plurality of longitudinal convex strips 103 are integratedly installed on the side where two parallel concrete panels 101 are close to each other, and a plurality of transverse convex strips 104 are integratedly installed on the upper surface of the other concrete panel 101.

[0052] A horizontal steel plate 3 is horizontally arranged between the ends of two adjacent precast panels 1 that are close to each other, and the lower surface of the horizontal steel plate 3 is closely attached to the upper surface of the adjacent concrete panel 101. Vertical steel plates 4 are vertically fixed on both sides of the horizontal steel plate 3, and one side of the vertical steel plate 4 is closely attached to one side of the adjacent concrete panel 101.

[0053] Among them, the first corrugated portion 301 is integrally installed at both ends of the horizontal steel plate 3, and the second corrugated portion 401 for partially inserting the steel bar bundling cage 2 is integrally installed at both ends of the vertical steel plate 4. A plurality of vertical slots 5 are spaced apart on the lower surface of the first corrugated portion 301, and at least two vertical rods 6 are inserted inside the vertical slots 5. A plurality of horizontal slots 7 are spaced apart on the lower surface of the second corrugated portion 401, and at least two horizontal rods 8 are inserted inside the horizontal slots 7. The lower ends of the vertical rods 6 and one ends of the horizontal rods 8 are respectively embedded in the adjacent concrete slabs 101 and fixedly connected to the inner reinforcement frame 102.

[0054] Before construction, prepare enough thick and thin steel bars in the factory, bend and bundle them into several inner reinforcement skeletons 102, and then weld a specified number of vertical bars 6 and horizontal bars 8 to the inner reinforcement skeletons 102 respectively, put them into the formwork and pour concrete, so that the inner reinforcement skeleton 102 with the vertical bars 6 and horizontal bars 8 is embedded in the concrete slab 101, and the shape of the formwork is retained to leave the space required for the longitudinal ribs 103 and the horizontal ribs 104, the vertical bars 6 and the horizontal bars 8 are partially extended, and several vertical slots 5 are cut into the horizontal steel plate 3, and several horizontal slots 7 are cut into the vertical steel plate 4, and then transported to the construction site by engineering vehicles for standby use.

[0055] Before pouring, scaffolding and formwork are built in sequence below the concrete composite beam to be constructed, and a specified number of precast panels 1 are placed into the formwork one by one along the axial direction and connected together, wherein the thin steel bars belonging to the inner reinforcement skeleton 102 are staggered with each other, and then tied and fixed with wire, and the positions at both ends of the concrete composite beam are tied and fixed with the supporting steel bars to complete the assembly, so that the coarse steel bars of the inner reinforcement skeleton 102 are partially immersed in the wavy inner recesses of the horizontal steel plate 3 and the vertical steel plate 4, respectively, the vertical rod 6 is immersed in the wavy outer recesses of the horizontal steel plate 3, and the horizontal rod 8 is immersed in the wavy outer recesses of the vertical steel plate 4, so that the horizontal steel plate 3 and the vertical steel plate 4 not only span the connection nodes of each precast panel 1, but also can use their wavy parts to firmly tighten the steel bar bundling cage 2 and the inner reinforcement skeleton 102, and can also leave space for the concrete to wrap the vertical rod 6 and the horizontal rod 8 as much as possible.

[0056] When preparing for pouring, first stick the horizontal steel plate 3 and the vertical steel plate 4 in turn on the inner side of the concave concrete slab 101 with mortar. During pouring, the front and back depressions of the first wave-shaped portion 301 are used to cover the vertical rod 6 and the horizontal convex strip 104 respectively, and the front and back depressions of the second wave-shaped portion 401 are used to cover the horizontal rod 8 and the longitudinal convex strip 103 respectively, and the inner rib skeleton 102 is partially inserted into the front depression of the first wave-shaped portion 301 and the front depression of the second wave-shaped portion 401 to achieve the reinforced connection of the internal and external structures of the pre-support 1, and then weld the connecting seams of the horizontal steel plate 3 and the vertical steel plate 4. After the connecting seams in the entire beam are welded, put the steel bar bundling cage 2 one by one, and start to spray concrete with a pump truck. At the same time, use an inserted concrete vibrator to generate high-frequency vibration waves that will propagate into the concrete, rearrange the concrete particles and tightly combine them, and discharge the bubbles and excess water therein. This process helps to reduce the porosity inside the concrete, improve the density and strength of the concrete, and demold the concrete after it is dried and hardened.

[0057] When loaded, the horizontal steel plates 3 and the vertical steel plates 4 form a concave support member spanning the connection nodes of each prefabricated panel 1, and use the horizontal steel plates 3 and the vertical rods 6 to resist the lateral shearing effect, and use the vertical steel plates 4 and the horizontal rods 8 to resist the vertical shearing effect. At the same time, the vertical rods 6 and the horizontal rods 8 tighten the internal reinforcement skeleton 102, so as to close the gaps at the connection nodes and hold each prefabricated panel 1 firmly. Compared with the traditional support method through steel bars, the support surface acting on the connection nodes of the prefabricated panels 1 is larger, thereby improving the shear resistance of the connection nodes of each prefabricated component.

[0058] Furthermore, both the horizontal steel plate 3 and the vertical steel plate 4 can be made of Q235B steel plate. This material based on low-carbon structural steel plate has good toughness and plasticity, is easy to process and weld, and has a thickness range of 1.2 to 60 mm. In the present embodiment, 50 mm is preferred. While it is convenient for grinding, it has a high structural strength and can resist shearing well. The width range is adjusted according to actual production standards and uses.

[0059] Refer to the attached Figure 2 , Figure 3 and Figure 6 A plurality of first grooves 302 are spaced apart on one side of the horizontal steel plate 3 close to the concrete slab 101, and a plurality of second grooves 402 are spaced apart on the lower surface of the vertical steel plate 4. When applying mortar, the first grooves 302 and the second grooves 402 are respectively used to accommodate mortar, and as much mortar as possible is added between the gaps between the horizontal steel plate 3 and the vertical steel plate 4 and the concrete slab 101, so that the horizontal steel plate 3 and the vertical steel plate 4 are more firmly bonded and not easy to fall off.

[0060] Refer to the attached Figure 3 and Figure 4 Both ends of the prefabricated board 1 are provided with step grooves 9 with a concave structure, and the inner walls of the step grooves 9 are coated with a waterproof coating 10. Before installing the horizontal steel plate 3 and the vertical steel plate 4, each step groove 9 can be grinded on the prefabricated board 1 by a grinder in the factory, and then the step grooves 9 are covered with a waterproof coating 10, so that the horizontal steel plate 3 and the vertical steel plate 4 form a concave support member that sticks to the waterproof coating 10, which can improve the waterproof performance of the connection node while providing support and anti-shearing effect.

[0061] Refer to the attached Figure 1 , Figure 3 and Figure 4A high-strength plastic plate 11 with a concave structure is inserted inside the step groove 9. The high-strength plastic plate 11 covers the adjacent horizontal steel plates 3 and vertical steel plates 4 from the outside. The high-strength plastic plate 11 partially extends out of the step groove 9. The high-strength plastic plate 11 is used to connect two adjacent step grooves 9. After applying the waterproof coating 10, mortar can be applied at the construction site, and the high-strength plastic plate 11 can be placed in it for bonding. The thickness of the concrete beam is compensated in the step groove 9, and the horizontal steel plate 3 and the vertical steel plate 4 form a concave support member that spans the connection nodes of each prefabricated panel 1 to increase the supporting strength of the concave support member.

[0062] Refer to the attached Figure 4 , Figure 5 and Figure 7 A vertical thread is provided in the middle of the upper surface of the vertical rod 6, and the vertical rod 6 is connected with a vertical fastener 12 for pressing the horizontal steel plate 3 through the vertical thread. After the horizontal steel plate 3 is firmly glued, the vertical fasteners 12 can be screwed onto the vertical rod 6 one by one along the vertical thread until the horizontal steel plate 3 is pressed to limit the position. There is no need to hold it with hands all the time. After pouring, the horizontal steel plate 3 is vertically supported in conjunction with concrete.

[0063] Refer to the attached Figure 2 , Figure 3 and Figure 5 A horizontal thread is provided in the middle of one end of the horizontal rod 8, and the horizontal rod 8 is connected with a horizontal fastener 13 for pressing the vertical steel plate 4 through the horizontal thread. After the vertical steel plate 4 is firmly glued, the horizontal fasteners 13 can be screwed onto the horizontal rod 8 one by one along the horizontal thread until the vertical steel plate 4 is pressed to limit the position. There is no need to hold it with hands all the time. After pouring, the vertical steel plate 4 is vertically supported in conjunction with concrete.

[0064] Among them, both the vertical fasteners 12 and the horizontal fasteners 13 can be screws, and are preferably cylindrical in the middle with fan-shaped ends extending outward, and a threaded column is axially fixed in the middle of the lower surface of the cylinder to adapt to the vertical thread and the horizontal thread.

[0065] Embodiment 2:

[0066] like Figure 8-Figure 11 As shown, an assembled cast-in-place concrete composite beam is basically the same as the first embodiment, and the same points can be referred to the first embodiment, and the difference is that:

[0067] The transverse steel plates 3 are all replaced by transverse steel bars 14, and at least two longitudinal steel kits 15 are arranged outside the transverse steel bars 14. One end of the longitudinal steel kits 15 is annularly sleeved outside the transverse steel bars 14, and the other end of the longitudinal steel kits 15 is rod-shaped and embedded in adjacent concrete slabs 101 and fixedly connected to the inner reinforcement skeleton 102. The transverse steel plates 3 that need to be welded are removed, and the transverse steel bars 14 are used in combination with the longitudinal steel kits 15 to tighten two adjacent inner reinforcement skeletons 102, which can still cross the connection nodes of each prefabricated panel 1, and the transverse steel bars 14 and the longitudinal steel kits 15 are used to resist the transverse shearing effect, which ensures sufficient support strength while further simplifying the construction steps.

[0068] Refer to the attached Figure 8 , Fig. 9 and Fig.11 The vertical steel plates 4 are replaced by longitudinal steel bars 16, and at least two transverse steel kits 17 are arranged outside the longitudinal steel bars 16. One end of the transverse steel kit 17 is annularly sleeved outside the longitudinal steel bars 16, and the other end of the transverse steel kit 17 is rod-shaped and embedded in the adjacent concrete slabs 101 and fixedly connected to the inner reinforcement skeleton 102. The vertical steel plates 4 that need to be welded are removed, and the longitudinal steel bars 16 are used in combination with the transverse steel kits 17 to tighten the two adjacent inner reinforcement skeletons 102, which can still cross the connection nodes of each prefabricated panel 1, and the longitudinal steel bars 16 and the transverse steel kits 17 are used to resist the vertical shearing effect, which ensures sufficient support strength and further simplifies the construction steps.

[0069] Refer to the attached Figure 8 and Fig.10 Both ends of the transverse reinforcement 14 and the longitudinal reinforcement 16 are of a hole structure, and a first annular pin 18 and a second annular pin 19 are respectively inserted through the holes. After the transverse reinforcement 14 and the longitudinal reinforcement 16 are installed, the first annular pin 18 and the second annular pin 19 are respectively installed, and the longitudinal steel kit 15 and the transverse steel kit 17 are used for limiting to prevent the transverse reinforcement 14 and the longitudinal reinforcement 16 from falling off, so that the transverse reinforcement 14 and the longitudinal reinforcement 16 can be locked at each connection node without welding and fixing, and the material is simple to obtain and can be directly buried in the concrete, and it will not hinder the reinforcement bundling cage 2 placed therein.

[0070] In order to facilitate the insertion of the first annular pin 18 and the second annular pin 19, the longitudinal ribs 103 and the transverse ribs 104 in the first embodiment are omitted, leaving enough installation space for easy installation.

[0071] Embodiment three:

[0072] In order to improve the shear resistance of prefabricated concrete beams, based on Example 1 and Example 2, to simplify the operation of building prefabricated cast-in-place concrete composite beams on buildings, we have made certain improvements to the traditional steps of on-site processing based on prefabricating certain accessories in the factory.

[0073] like Fig.12As shown, a method for constructing an assembled cast-in-place concrete composite beam comprises the following steps:

[0074] S1, prefabricated accessories: prepare enough thick and thin steel bars in the workshop, bend and bundle them into a plurality of inner reinforcement skeletons 102, and then weld the specified number of vertical bars 6 and horizontal bars 8 in the first embodiment to the inner reinforcement skeletons 102 to make a base skeleton;

[0075] Alternatively, the specified number of longitudinal steel sets 15 and transverse steel sets 17 in the second embodiment are welded to the inner rib frame 102 to form a base frame;

[0076] The vertical rod 6 and the horizontal rod 8 can be in the shape of a round rod, a rectangular parallelepiped, a hexagonal prism, an octagonal prism, etc., with the requirement of convenient material acquisition and increasing the bonding area between the two and the concrete as much as possible;

[0077] A plurality of vertical slots 5 are cut out of the horizontal steel plate 3, the width of the vertical slots 5 is slightly larger than the width of the vertical rod 6, and a plurality of horizontal slots 7 are cut out of the vertical steel plate 4, the width of the horizontal slots 7 is slightly larger than the width of the horizontal rod 8;

[0078] S2, pre-installation of the plant: the prefabricated base frame is placed in a hollow concave formwork, concrete is poured, and embedded in the concrete slab 101. The three concrete slabs 101 are integrally formed in a concave shape, and the vertical bars 6 and the horizontal bars 8 partially extend out of the concrete slab 101;

[0079] Alternatively, the longitudinal steel set 15 and the transverse steel set 17 each partially extend out of the concrete slab 101;

[0080] S3, site preparation: build scaffolding and formwork in sequence below the concrete composite beam to be constructed, put a specified number of prefabricated panels 1 into the formwork one by one along the axial direction and connect them together, first cover the step groove 9 with a waterproof coating 10, and then use mortar to glue the high-strength plastic board 11;

[0081] Then, the horizontal steel plate 3 and the vertical steel plate 4 in the first embodiment are sequentially adhered to the inner side of the concave concrete slab 101 by mortar, so that the vertical slots 5 are all sleeved with the vertical rods 6, and the horizontal slots 7 are all sleeved with the horizontal rods 8, and then the connecting seams of the horizontal steel plate 3 and the vertical steel plate 4 are welded to form a concave support member;

[0082] Alternatively, the transverse steel bars 14 in the second embodiment are passed through the corresponding longitudinal steel sets 15 one by one, and the longitudinal steel bars 16 are passed through the corresponding transverse steel sets 17 one by one, and a plurality of first annular pins 18 are used to lock the two ends of the transverse steel bars 14, and a plurality of second annular pins 19 are used to lock the two ends of the longitudinal steel bars 16, as concave support members;

[0083] Thus, the concave support member is used to connect two adjacent base frames, spanning the connection nodes of each prefabricated panel 1 to resist the shearing action;

[0084] S4, on-site processing: After the welding of the connecting seams in the entire beam is completed, the steel bar bundling cages 2 are placed one by one, and two adjacent steel bar bundling cages 2 are tied and fixed with wires, wherein the thin steel bars belonging to the inner reinforcement frame 102 are staggered and then tied and fixed with wires, and the positions at both ends of the concrete composite beam are tied and fixed with the supporting steel bars to complete the assembly;

[0085] S5, pouring: Start to spray concrete with a pump truck and use an inserted concrete vibrator at the same time. The high-frequency vibration waves generated will propagate into the concrete, causing the concrete particles to rearrange and combine tightly, while expelling bubbles and excess water;

[0086] At this time, quickly insert the vibrator into the concrete. The insertion depth is usually about 10 cm. During the vibration process, the vibrator should be kept vertical or slightly tilted to avoid collision with the formwork or steel bars. The vibration time should be controlled between 20 and 30 seconds until the concrete no longer emits bubbles and the surface is slurry. The moving distance should be controlled at about 30 to 50 cm to ensure that the concrete can be vibrated evenly to avoid omissions.

[0087] When pulling out the vibrating rod, it should be done slowly to reduce the voids. This process helps to reduce the porosity inside the concrete, improve the density and strength of the concrete, and demould after the concrete is dry and hardened;

[0088] S6. Demoulding: If it is located at the main beam frame of the building, it usually takes more than 4 to 5 days to remove the mould. If the concrete beam is poured at the roof position, the waiting time may be longer, generally more than 5 days;

[0089] For formwork with a width of less than 2m, the demolding time may be around 3 to 4 days; while for large-span beams with a width of more than 8m, the demolding time may need to be extended to 10 days or even longer;

[0090] Secondly, it is necessary to wait until the strength of the concrete reaches more than 75% of the design requirements before the formwork can be removed. For important structures or components with special requirements, it may be necessary to wait until the concrete strength reaches 100% before the formwork can be removed.

[0091] It can be seen that the assembled cast-in-place concrete composite beam established through the above steps has significantly reduced parts that need to be welded, especially compared with the traditional method of overlapping multiple steel bars. Each connection node only needs to weld two connection seams. When loaded, the horizontal steel plate 3 and the vertical steel plate 4 form a concave support member that spans the connection nodes of each prefabricated panel 1, and the horizontal steel plate 3 and the vertical rod 6 are used to resist the lateral shear effect, and the vertical steel plate 4 and the horizontal rod 8 are used to resist the vertical shear effect. At the same time, the vertical rod 6 and the horizontal rod 8 tighten the internal reinforcement skeleton 102, so that the gaps at the connection nodes are closed while holding each prefabricated panel 1 firmly. Compared with the traditional method of supporting through steel bars, the support surface acting on the connection nodes of the prefabricated panels 1 is larger, thereby improving the shear resistance of the connection nodes of each prefabricated part.

[0092] The above is only a preferred embodiment of the present invention. It should be noted that, for those skilled in the art, several improvements and modifications can be made without departing from the principles of the present invention, and these improvements and modifications should also be considered as the protection scope of the present invention. The structures, devices and operating methods not specifically described and explained in the present invention shall be implemented according to the conventional means in the art unless otherwise specified and limited.

Claims

1. An assembled cast-in-place concrete composite beam, comprising a plurality of steel bar bundling cages (2) and a prefabricated plate (1) located outside the steel bar bundling cages (2), characterized in that: The prefabricated panels (1) each comprise three integrated concavely distributed concrete panels (101), each of the concrete panels (101) being provided with an internal reinforcement frame (102) and a pulling member fixedly connected to the internal reinforcement frame (102), the concrete panels (101) extending out of both ends of the internal reinforcement frame (102), wherein a plurality of longitudinal convex strips (103) are integrally mounted on one side of two parallel concrete panels (101) close to each other, and a plurality of transverse convex strips (104) are integrally mounted on the upper surface of the other concrete panel (101); A concave support member is provided between the ends of two adjacent prefabricated panels (1) that are close to each other, and a first corrugated portion (301) and a second corrugated portion (401) are provided at both ends of the concave support member, a plurality of vertical slots (5) are provided at intervals on the lower surface of the first corrugated portion (301), and a plurality of horizontal slots (7) are provided at intervals on the lower surface of the second corrugated portion (401); During casting, the first corrugated portion (301) and the second corrugated portion (401) are used to respectively enclose the pulling member, the longitudinal convex strip (103) and the transverse convex strip (104); when loaded, the inner reinforcement frame (102) uses a concave support member in cooperation with the pulling member to span the connection nodes of each prefabricated panel (1), so that the support surface acting on the connection nodes of the prefabricated panel (1) is larger, thereby improving the shear resistance of the connection nodes of each prefabricated component.

2. The assembled cast-in-place concrete composite beam according to claim 1, characterized in that: The concave support member comprises a transverse steel plate (3) and two vertical steel plates (4) respectively fixed on both sides of the transverse steel plate (3); the lower surface of the transverse steel plate (3) is closely attached to the upper surface of the adjacent concrete plate (101); one side of the vertical steel plate (4) is closely attached to one side of the adjacent concrete plate (101); the first corrugated portion (301) is integrally mounted on the end of the transverse steel plate (3); and the second corrugated portion (401) is integrally mounted on the end of the vertical steel plate (4).

3. The assembled cast-in-place concrete composite beam according to claim 2, characterized in that: A plurality of first grooves (302) are provided at intervals on a side of the transverse steel plate (3) close to the concrete plate (101), and a plurality of second grooves (402) are provided at intervals on the lower surface of the vertical steel plate (4).

4. The assembled cast-in-place concrete composite beam according to claim 3, characterized in that: The pulling member comprises a vertical rod (6) and a horizontal rod (8) embedded in the concrete slab (101); one end of the vertical rod (6) and one end of the horizontal rod (8) are fixedly connected to the inner rib frame (102); the other ends of the vertical rod (6) pass through the vertical slot (5); and the other ends of the horizontal rod (8) pass through the horizontal slot (7).

5. The assembled cast-in-place concrete composite beam according to claim 1, characterized in that: Both ends of the prefabricated plate (1) are provided with step grooves (9) with a concave structure, and high-strength plastic plates (11) with a concave structure are inserted inside the step grooves (9). The high-strength plastic plates (11) are sheathed around adjacent horizontal steel plates (3) and vertical steel plates (4) from the outside, and the high-strength plastic plates (11) partially extend out of the step grooves (9). The high-strength plastic plates (11) are used to connect two adjacent step grooves (9).

6. The assembled cast-in-place concrete composite beam according to claim 4, characterized in that: A vertical thread is provided in the middle of the upper surface of each of the vertical rods (6), and each of the vertical rods (6) is connected to a vertical fastener (12) for pressing the horizontal steel plate (3) via the vertical thread.

7. The assembled cast-in-place concrete composite beam according to claim 4, characterized in that: A horizontal thread is provided in the middle of one end of each of the cross bars (8), and each of the cross bars (8) is connected to a horizontal fastener (13) for pressing the vertical steel plate (4) via the horizontal thread.

8. The assembled cast-in-place concrete composite beam according to claim 2, characterized in that: The transverse steel plates (3) are replaced by transverse steel bars (14), and at least two longitudinal steel sets (15) are arranged outside the transverse steel bars (14). One end of the longitudinal steel sets (15) is annularly sleeved outside the transverse steel bars (14), and the other end of the longitudinal steel sets (15) is rod-shaped and embedded in an adjacent concrete slab (101) to be fixedly connected to the inner reinforcement frame (102).

9. The assembled cast-in-place concrete composite beam according to claim 8, characterized in that: The vertical steel plates (4) are replaced by longitudinal steel bars (16), and at least two transverse steel sets (17) are arranged outside the longitudinal steel bars (16). One end of the transverse steel set (17) is annularly sleeved outside the longitudinal steel bars (16), and the other end of the transverse steel set (17) is rod-shaped and embedded in an adjacent concrete slab (101) to be fixedly connected to the inner reinforcement frame (102).

10. A method for constructing an assembled cast-in-place concrete composite beam, applied to an assembled cast-in-place concrete composite beam according to any one of claims 1 to 9, characterized in that: The following steps are involved: S1, prefabricated accessories: the coarse steel bars and fine steel bars in the factory are bent and bundled into a plurality of internal reinforcement frames (102) to make a base frame; S2, pre-installation of the factory building: placing the prefabricated inner reinforcement frame (102) into the hollow concave formwork and pouring concrete, so that the base frame part extends out of the concrete slab (101); S3, site preparation: build scaffolding and formwork, place a specified number of prefabricated panels (1) one by one in the formwork along the axial direction and connect them together, first cover the step groove (9) with a waterproof coating (10), then use mortar to glue the high-strength plastic sheet (11), make a concave support member to connect two adjacent base frames, span the connection nodes of each prefabricated panel (1), and resist the shearing effect; S4, on-site processing: after the concave support members in the entire beam are connected to the base frame, the steel bar bundling cages (2) are placed one by one, and two adjacent steel bar bundling cages (2) are tied and fixed with wire to complete the assembly; S5, pouring: Use a pump truck to spray concrete, and use an inserted concrete vibrator at the same time, the high-frequency vibration waves generated will propagate into the concrete; S6. Demoulding: If the concrete beam is cast on the main beam frame of the building, wait at least 4 to 5 days before demolding; or if the concrete beam is cast on the roof, wait at least 5 days before demolding.

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