Fabricated prestressed floor plate-concrete steel-clad column plate-column structure and construction method

Abstract

The invention relates to a fabricated prestressed floor plate-concrete steel-clad column plate-column structure and a construction method, and belongs to the technical field of building structure engineering, the fabricated prestressed floor plate-concrete steel-clad column plate-column structure comprises a concrete steel-clad column and an overhanging composite plate, the overhanging composite plate is arranged at a joint of the concrete steel-clad column and a prestressed floor plate, and the overhanging composite plate and the concrete steel-clad column are poured into a whole; the overhanging composite board comprises a reinforcing mesh arranged on the upper portion and a profiled steel sheet arranged at the bottom, the overhanging composite board is formed after concrete is poured on the overhanging composite board, and the reinforcing mesh is fixedly connected with the column reinforcing steel bars. And the overhanging composite plate and the prestressed floor plate are connected into a whole through the circumferential steel cover plate and bolts at the joint position. The prestressed profiled steel sheet concrete composition plate and the concrete steel-clad column are simultaneously applied to the plate-column joint, and the advantages of an assembly mode are combined, so that the punching-resistant bearing capacity and ductility of the plate-column structure are improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of building structure engineering, and particularly relates to a precast prestressed floor slab - concrete - encased steel column slab - column structure and a construction method thereof. Background Art

[0002] Due to its strong flexibility in plane layout, the slab - column structure can significantly reduce the structural floor height, has a fast construction speed, and low engineering costs, and is thus increasingly widely used in multi - storey factories and underground garages. However, during its application and popularization, there are still some problems. Since the slab - column structure belongs to the structure of point - supported slabs, the stress in the joint area is particularly complex under load. The slab area near the column is in a typical three - dimensional stress state and is extremely prone to brittle punching failure without obvious signs. At the same time, the brittle - failure joint will form an obvious punching - failure cone, and the load it originally bears will be redistributed to adjacent joints, thereby triggering a continuous collapse accident of the entire structure from local damage.

[0003] Currently, the conventional method to enhance the punching performance of the slab - column structure is to configure punching - shear reinforcement in the joint area. Although this method improves the punching - shear performance of the slab - column structure to a certain extent, due to the congestion of reinforcement in the joint area, it is difficult to install the punching - shear reinforcement, and sufficient bond - anchorage performance of the reinforcement also needs to be ensured in the slab - column joint. Analyzing from the stress perspective, this method has great limitations in improving the ductility of the structure and cannot improve the brittle punching - failure mode.

[0004] The prestressed profiled - steel - sheet concrete composite slab is to pour a certain thickness of concrete on profiled steel sheets with different cross - section forms, pass and tension prestressing tendons through the reserved ducts in the profiled - steel - sheet concrete slab. Then, through various strengthening measures, the interaction between the profiled steel sheet and the concrete is ensured, enabling the two to work together synergistically and giving full play to the respective advantages of the profiled steel sheet and the concrete, which has good application prospects in large - span structures. The concrete - encased steel column refers to a steel - concrete composite column in which steel shapes or steel - tube concrete are embedded inside a reinforced - concrete column. Compared with reinforced - concrete columns, the steel - reinforced concrete column has the advantages of high axial - compression bearing capacity and strong impact resistance, has good ductility and energy - dissipation capacity under axial pressure and cyclic horizontal loads, and usually has a smaller cross - section and lighter self - weight, and has good application value in precast concrete structures. Summary of the Invention

[0005] Based on the above - mentioned technical drawbacks, the present invention proposes a precast prestressed floor slab - concrete - encased steel column slab - column structure and a construction method thereof. By applying the prestressed profiled - steel - sheet concrete composite slab and the concrete - encased steel column to the slab - column joint at the same time and combining the advantages of precast assembly, the punching - shear bearing capacity and ductility of the slab - column structure are improved.

[0006] To achieve the above technical objectives, the present invention adopts the following technical solutions:

[0007] An assembled prestressed floor slab - concrete - encased steel column slab - column structure, comprising a concrete - encased steel column and an extended composite slab. The extended composite slab is arranged at the connection node between the concrete - encased steel column and the prestressed floor slab. The extended composite slab is cast integrally with the concrete - encased steel column and is used to connect the prestressed floor slab. The concrete - encased steel column is a concrete - encased steel column formed by welding stud bolts on the surface of the steel column and binding column steel bars around the steel column and then casting. The extended composite slab includes a steel mesh arranged on the upper part and a profiled steel sheet arranged at the bottom. After casting concrete thereon, the extended composite slab is formed. The steel mesh is fixedly connected to the column steel bars. After the extended composite slab is butted with the prestressed floor slab, the joint position is connected integrally by a circumferential steel cover plate through bolts to connect the extended composite slab and the prestressed floor slab.

[0008] Further, one end of the extended composite slab close to the prestressed floor slab to be connected is reserved with a hole for the bolt to penetrate. One end of the prestressed floor slab close to the extended composite slab to be connected is provided with a hole for the bolt to penetrate. After the extended composite slab is butted with the prestressed floor slab, an upper circumferential steel cover plate is arranged at the top and a lower circumferential steel cover plate is arranged at the bottom. The upper and lower circumferential steel cover plates are fixedly connected to the extended composite slab and the prestressed floor slab respectively through bolts.

[0009] Further, the concrete - encased steel column is a steel - reinforced concrete column or a stiffened steel - pipe concrete column.

[0010] Further, the joints between the prestressed floor slabs are fixedly connected by construction glue.

[0011] Further, the prestressed floor slab includes a steel mesh on the upper part and a profiled steel sheet on the lower part. A hole for the unbonded prestressed tendon to pass through is reserved in the prestressed floor slab. One end close to the extended composite slab to be connected is reserved with a hole for the bolt to penetrate. After casting concrete, the prestressed floor slab is formed.

[0012] Further, after the prestressed floor slabs are assembled, the unbonded prestressed tendons are passed through the reserved holes of the prestressed floor slabs. The prestressed tendons are symmetrically and bidirectionally distributed in the prestressed floor slabs, and the prestressed tendons are tensioned and anchored with anchors.

[0013] Further, after the prestressed floor slabs are tensioned with the prestressed tendons, mortar is injected into the reserved holes of the prestressed floor slabs to prevent rust.

[0014] Further, the upper and lower circumferential steel cover plates are rectangular - shaped flat steel plates.

[0015] Construction method of precast prestressed floor slab - concrete - filled steel column slab - column structure, including preparing an integral structure of concrete - filled steel column and extended composite slab, welding a number of stud bolts on the surface of the steel column, binding a steel bar column around it, at the connection node of the concrete - filled steel column and the extended composite slab, binding and fixedly connecting the steel bar column with the steel bar mesh of the extended composite slab, laying profiled steel sheets below the steel bar mesh, reserving holes for bolts to penetrate and prestressing tendon holes at one end of the extended composite slab close to the prestressed floor slab to be connected, and pouring concrete to form a concrete - filled steel column with an extended composite slab at the node; aligning and splicing the prestressed floor slab with the extended composite slab, respectively arranging upper and lower circumferential steel cover plates at the top and bottom of the joint position, and the connection end and joint of the extended composite slab and the prestressed floor slab are between the upper and lower circumferential steel cover plates, and fixedly connecting through bolts penetrating.

[0016] Furthermore, it also includes fixedly connecting the joints between prestressed floor slabs with construction glue, passing unbonded prestressing tendons through the reserved holes of the prestressed floor slabs, the unbonded prestressing tendons are symmetrically distributed bidirectionally in the prestressed floor slabs, tensioning the prestressing tendons and anchoring them with anchor devices, and injecting cement mortar in the reserved holes of the prestressed floor slabs to prevent rust for completion of assembly.

[0017] Advantages and effects of the present invention:

[0018] The present invention applies prestressed profiled steel sheet - concrete composite slabs and concrete - filled steel columns to slab - column joints at the same time, and combines the advantages of prefabrication, and proposes a new type of slab - column structure of precast prestressed composite lightweight floor slab - concrete - filled steel column. This new structure can improve the punching shear bearing capacity and ductility of the slab - column structure, realizes the transformation from cast - in - place structure to precast structure, and synchronously improves the mechanical properties of slab - column joints. Description of the drawings

[0019] Figure 1 It is the overall schematic diagram of the precast prestressed floor slab - concrete - filled steel column slab - column structure of the present invention;

[0020] Figure 2 It is the partial schematic diagram of the precast prestressed floor slab - concrete - filled steel column slab - column joint of the present invention;

[0021] Figure 3 It is Figure 2 The A - A sectional view of

[0022] Figure 4 It is Figure 2 The B - B sectional view of

[0023] Figure 5 It is the schematic diagram of the structure of the extended composite slab and the concrete - filled steel column when the steel column is a cross - shaped steel;

[0024] Figure 6 It is Figure 5C-C cross-sectional view;

[0025] Figure 7 is Figure 5 D-D cross-sectional view;

[0026] Figure 8 is a schematic diagram of the extended composite plate and concrete-filled steel column structure when the steel column is a stiffened steel pipe;

[0027] Figure 9 is Figure 8 E-E cross-sectional view;

[0028] Figure 10 is Figure 8 F-F cross-sectional view;

[0029] Figure 11 is a schematic diagram of the distribution of prestressed tendons with concentrated distribution in column strip and uniform distribution in mid-span strip;

[0030] Figure 12 is a schematic diagram of the distribution of prestressed tendons with concentrated distribution in column strip;

[0031] Figure 13 is a schematic diagram of the distribution of prestressed tendons with concentrated distribution in mid-span strip;

[0032] Figure 14 is a schematic diagram of the distribution of prestressed tendons with uniform distribution in positive plate.

[0033] In the figure: 1 is the concrete-filled steel column, 2 is the prestressed floor slab, 3 is the slab joint, 4 is the joint of the local prestressed composite lightweight floor slab - concrete-filled steel column, 5 is the column steel bars, 6 is the steel mesh, 7 is the extended composite plate, 8 is the profiled steel sheet, 9 is the unbonded prestressed tendon, 10 is the bolt, 11 is the circumferential steel cover plate, 12 is the stud, 13 is the cross-shaped steel, 14 is the stiffened circular steel pipe, 15 is the core concrete. Detailed implementation manners

[0034] The present invention will be further explained below in conjunction with the accompanying drawings and embodiments.

[0035] The present invention provides an assembled prestressed floor slab - concrete-filled steel column slab-column structure and construction method, as Figure 1-10As shown in the figure, it includes a concrete - encased steel column 1 and an extended composite slab 7. The extended composite slab 7 is arranged at the connection node between the concrete - encased steel column 1 and the prestressed floor slab 2, and is arranged around the periphery of the connection node of the prestressed floor slab 2 for connecting the prestressed floor slab 2. The extended composite slab 7 is cast integrally with the concrete - encased steel column 1. The concrete - encased steel column 1 is formed by welding stud bolts 12 on the surface of the steel column and then binding column reinforcement bars 5 around the steel column and pouring concrete. The extended composite slab 7 includes a steel mesh 6 arranged on the upper part and a profiled steel sheet 8 arranged at the bottom. After pouring concrete on it, the extended composite slab 7 is formed. The steel mesh 6 is bound and fixedly connected with the column reinforcement bars 5 to form a steel reinforcement cage. After the extended composite slab 7 is butted with the prestressed floor slab 2, at the joint position, the extended composite slab 7 and the prestressed floor slab 2 are connected into a whole by bolts through a circumferential steel cover plate. The novel floor slab - concrete - encased steel column structure of the present invention can improve the punching shear bearing capacity and ductility of the slab - column structure, realizes the transformation from the cast - in - place structure to the prefabricated structure, and simultaneously improves the mechanical properties of the slab - column joint.

[0036] Specifically, the concrete - encased steel column 1 can be a steel - reinforced concrete column or a stiffened steel - tube concrete column. Figure 2-7 It is an implementation scheme of a cross - shaped steel - reinforced concrete column. Figure 8-10 It is an implementation scheme of a stiffened steel - tube concrete column. Whether it is a steel - reinforced concrete column or a stiffened steel - tube concrete column, several symmetric or staggered stud bolts 12 are uniformly welded on the front, back, left, and right four directions of the surface of the cross - shaped steel 13 or the stiffened circular steel tube 14 from top to bottom. The purpose of welding the stud bolts 12 is to strengthen the bond between the steel column and the concrete, enhance the connection strength, form an integral joint force, and ensure the overall stability and bearing capacity of the structure. Then, the reinforcement column 5 is bound around it. At the connection node between the concrete - encased steel column 1 and the extended composite slab 7, the reinforcement column 5 is bound and fixedly connected with the steel mesh 6 of the extended composite slab 7. Specifically, at the node position of the column reinforcement bars 5, the extended composite slab reinforcement bars 6 perpendicular to the column reinforcement bars 5 are transversely bound and connected. The profiled steel sheet 8 is selected according to the design requirements, and the upper - layer bidirectional reinforcement bars 6 are bound. In the composite floor slab 2, a duct for the unbonded prestressed tendon 9 to pass through is reserved, and a duct for the through - bolt 10 to pass through is reserved at the connection. Concrete is poured to form a prestressed composite floor slab 2 with reserved bolt holes. Among them, the concrete poured inside the circular steel tube of the stiffened circular steel tube 14 is the core concrete 15. One end of the extended composite slab 7 close to the prestressed floor slab 2 to be connected reserves a duct for the bolt to pass through, and concrete is poured to form a concrete - encased steel column 1 with an extended composite slab 7 at the node.

[0037] The prestressed floor slab 2 is aligned and spliced with the extended composite slab 7. Upper and lower circumferential steel cover plates 11 are respectively arranged at the top and bottom of the joint position. Between the upper and lower circumferential steel cover plates are the connection ends and joints of the extended composite slab 7 and the prestressed floor slab 2, which are fixedly connected by passing through high-strength bolts 10. Specifically, a hole for the bolt to pass through is reserved at one end of the extended composite slab 7 close to the stress floor slab to be connected, and a hole for the bolt to pass through is provided at one end of the prestressed floor slab 2 close to the extended composite slab 7 to be connected. After the extended composite slab 7 and the prestressed floor slab 2 are butted, an upper circumferential steel cover plate is arranged at the top and a lower circumferential steel cover plate is arranged at the bottom. The upper and lower circumferential steel cover plates are respectively fixedly connected with the extended composite slab 7 and the prestressed floor slab 2 by bolts. Specifically, the high-strength bolt 10 is passed through the upper circumferential steel cover plate, the composite slab and the lower circumferential steel cover plate from top to bottom in sequence, and the nut is tightened to realize the sandwich assembly of the top and bottom steel cover plates and the composite slab. More specifically, the upper and lower circumferential steel cover plates are rectangular plane steel plates with a loop shape. The column reinforcement 5 passes through the hollow center of the circumferential steel cover plate 11, covering the joints and the connecting positions on both sides of the extended composite slab 7 and the prestressed floor slab 2.

[0038] Specifically, the prestressed floor slab 2 includes a steel mesh at the upper part and a profiled steel sheet at the lower part. A hole for the unbonded prestressed tendon 9 to pass through is reserved in the prestressed floor slab 2, and a hole for the bolt to pass through is reserved at one end close to the extended composite slab 7 to be connected. Concrete is poured to form the prestressed floor slab 2.

[0039] The joint between the prestressed floor slab 2 and the prestressed floor slab 2 is fixedly connected with construction glue, specifically it can be construction glue (epoxy adhesive). The unbonded prestressed tendon 9 is passed through the reserved hole of the prestressed floor slab 2. The unbonded prestressed tendon 9 is symmetrically and bidirectionally distributed in the prestressed floor slab 2. The prestressed tendon is tensioned and anchored with an anchor. The distribution methods of the prestressed tendon can be divided into four categories: concentrated distribution in the column strip, uniform distribution in the middle strip; concentrated distribution in the column strip; concentrated distribution in the middle strip; uniform distribution in the whole slab. For the distribution methods of the prestressed tendon, see Figure 11-14 , and then mortar is injected into the reserved hole of the prestressed floor slab 2 to prevent rust and complete the assembly.

Claims

1. Prefabricated prestressed floor slab-concrete steel column slab column structure, characterized by: The invention comprises a concrete-clad steel column (1) and an extended composite plate (7). The extended composite plate (7) is arranged at the connection node between the concrete-clad steel column (1) and the prestressed floor plate (2). The extended composite plate (7) and the concrete-clad steel column (1) are cast as a whole. The extended composite plate (7) is used to connect the prestressed floor plate (2). The concrete-clad steel column (1) is a concrete-clad steel column (1) formed by welding bolts (12) on the surface of the steel column, tying column steel bars (5) around the outer periphery of the steel column, and then casting. The extended composite plate (7) comprises a steel mesh (6) arranged on the top and a corrugated steel plate (8) arranged on the bottom. After concrete is cast on the steel mesh (6), the extended composite plate (7) is formed. The steel mesh (6) is fixedly connected to the column steel bars (5). After the extended composite plate (7) and the prestressed floor plate (2) are butt-jointed, the extended composite plate (7) and the prestressed floor plate (2) are connected as a whole at the joint position through bolts via an annular steel cover plate.

2. The assembled prestressed floor slab-concrete steel-column-slab-column structure according to claim 1 is characterized by: A hole for bolts to pass through is reserved at one end of the protruding composite plate (7) close to the prestressed floor plate to be connected, and a hole for bolts to pass through is provided at one end of the prestressed floor plate (2) close to the protruding composite plate (7) to be connected. After the protruding composite plate (7) and the prestressed floor plate (2) are butt-jointed, an upper annular steel cover plate is provided on the top and a lower annular steel cover plate is provided on the bottom. The upper and lower annular steel cover plates are fixedly connected to the protruding composite plate (7) and the prestressed floor plate (2) respectively by bolts.

3. The assembled prestressed floor slab-concrete steel-column-slab-column structure according to claim 1 is characterized by: The concrete-coated steel column (1) is a steel-concrete column or a rigid steel tube concrete column.

4. The assembled prestressed floor slab-concrete steel-column-slab-column structure according to claim 1 is characterized in that: The joints between the prestressed floor slabs (2) and the prestressed floor slabs (2) are fixedly connected by means of construction adhesive.

5. The assembled prestressed floor slab-concrete-coated steel column-slab-column structure according to claim 1 is characterized in that: The prestressed floor slab (2) comprises an upper steel mesh and a lower corrugated steel plate. A hole is reserved in the prestressed floor slab (2) for the non-bonded prestressed tendons (9) to pass through. A hole is reserved near one end of the extended composite plate (7) to be connected for the bolts to pass through. Concrete is poured to form the prestressed floor slab (2).

6. The assembled prestressed floor slab-concrete-coated steel column-slab-column structure according to claim 5 is characterized by: After the prestressed floor slab (2) is assembled, the unbonded prestressed tendons (9) are passed through the reserved channels of the prestressed floor slab (2) and the extended composite slab (7), the prestressed tendons (9) are symmetrically bidirectionally distributed in the prestressed floor slab (2), the prestressed tendons are tensioned and anchored with anchors.

7. The assembled prestressed floor slab-concrete steel-column-slab-column structure according to claim 5 is characterized by: After the prestressed tendons are tensioned in the prestressed floor slab (2), cement mortar is injected into the reserved channels of the prestressed floor slab (2) to prevent rust.

8. The assembled prestressed floor slab-concrete steel-column-slab-column structure according to claim 1 is characterized by: The upper and lower annular steel cover plates are U-shaped flat steel plates.

9. The construction method of the assembled prestressed floor slab-concrete steel-column-slab-column structure according to any one of claims 1 to 8, characterized in that: The invention comprises preparing a structure of a concrete-encased steel column (1) and an extended composite plate (7), welding a plurality of bolts on the surface of the steel column, tying a steel bar column (5) around the steel column, tying and fixing the steel bar column (5) and the steel mesh (6) of the extended composite plate (7) at the connection node between the concrete-encased steel column (1) and the extended composite plate (7), arranging a corrugated steel plate (8) below the steel mesh (6), reserving a hole for bolts to penetrate and a prestressed tendon hole at one end of the extended composite plate (7) close to the prestressed floor plate (2) to be connected, pouring concrete to form a concrete-encased steel column (1) with the extended composite plate (7) at the node; the prestressed floor plate (2) and the extended composite plate (7) are aligned and spliced, upper and lower annular steel cover plates are respectively arranged at the top and bottom of the joint position, and the connection end and joint of the extended composite plate (7) and the prestressed floor plate (2) are between the upper and lower annular steel cover plates, which are fixedly connected by bolts penetrating through them.

10. The construction method of the assembled prestressed floor slab-concrete steel-column-slab-column structure according to claim 9 is characterized in that: The method also includes fixing the joints between the prestressed floor slabs (2) with construction adhesive, passing the unbonded prestressed tendons (9) through the reserved channels of the prestressed floor slabs (2) and the extended composite slabs (7), symmetrically bidirectionally distributing the unbonded prestressed tendons (9) in the prestressed floor slabs (2), tensioning the prestressed tendons and anchoring them with anchors, and injecting cement mortar into the reserved channels of the prestressed floor slabs (2) to prevent rust and complete the assembly.

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