A flexible reinforcement prefabricated assembly connection structure and construction method thereof

Abstract

The present invention relates to the technical field of bridge engineering, and in particular to a flexible reinforcement prefabricated assembly connection structure and a construction method thereof. The flexible reinforcement prefabricated assembly connection structure is used to realize the connection between the prefabricated bridge pier and the abutment, wherein a reserved longitudinal reinforcement connection section is provided on the prefabricated bridge pier, and a reserved vertical reinforcement connection section is provided on the abutment; the flexible reinforcement prefabricated assembly connection structure includes a reserved longitudinal reinforcement connection section, a reserved vertical reinforcement connection section, a reinforcement joint, and a flexible reinforcement, wherein the reserved longitudinal reinforcement connection section is vertically aligned with the reserved vertical reinforcement connection section, and the flexible reinforcement is connected to the reserved longitudinal reinforcement connection section and the reserved vertical reinforcement connection section through a reinforcement joint. Stirrups are arranged on the periphery of the flexible reinforcement to meet the shear resistance requirements and improve the compressive strength of the core concrete; the present invention can improve the construction tolerance of the connection part without significantly increasing the construction cost, and the entire system is simple to construct and easy to operate, which can improve the construction efficiency and facilitate the prefabrication and assembly connection of concrete piers, columns, beams or shear walls.

Description

Technical Field

[0001] The invention relates to the technical field of bridge engineering, and in particular to a flexible reinforcement prefabricated assembly connection structure and a construction method thereof. Background Art

[0002] For the prefabrication and assembly of bridge substructures, the performance of the connection between prefabricated components directly affects the static and dynamic response of the structure. The safety, durability, construction convenience and seismic performance of the connection structure are the key factors that limit the promotion and application of prefabrication and assembly technology in bridge substructures. Domestic and foreign researchers and engineering designers have proposed a variety of schemes for the connection structure between piers and abutments or piers and cap beams of prefabricated substructures based on factors such as bridge type characteristics, construction conditions and engineering environment. The most widely used ones are grouting sleeve connection, grouting metal bellows connection, and mechanical connection. The results of the quasi-static test show that the above connection methods can achieve the same bearing capacity and ductility as cast-in-place when combined with the non-bonding treatment of longitudinal reinforcement. It should be noted that the construction tolerance of grouting sleeve connection, grouting metal bellows connection and mechanical connection is small, about 2 cm, and the positioning accuracy of the reserved longitudinal reinforcement connection section and the reserved vertical reinforcement of the abutment is required to be high. Summary of the invention

[0003] In order to solve the above problems, the purpose of the present invention is to provide a flexible reinforcement prefabricated assembly connection structure and a construction method thereof. The flexible reinforcement prefabricated assembly connection structure is used to realize the connection between the prefabricated bridge pier and the abutment, wherein a reserved longitudinal reinforcement connection section is provided on the prefabricated bridge pier, and a reserved vertical reinforcement connection section is provided on the abutment; the flexible reinforcement prefabricated assembly connection structure includes a reserved longitudinal reinforcement connection section, a reserved vertical reinforcement connection section, a reinforcement joint, and a flexible reinforcement, wherein the reserved longitudinal reinforcement connection section is vertically aligned with the reserved vertical reinforcement connection section, and the flexible reinforcement is connected to the reserved longitudinal reinforcement connection section and the reserved vertical reinforcement connection section through a reinforcement joint. Stirrups are arranged on the periphery of the flexible reinforcement to meet the shear resistance requirements and improve the compressive strength of the core concrete; the present invention can improve the construction tolerance of the connection part without significantly increasing the construction cost, and the whole system is simple to construct and easy to operate, which can improve the construction efficiency and facilitate the prefabrication and assembly connection of concrete piers, columns, beams or shear walls.

[0004] The purpose of the present invention can be achieved by the following technical solutions:

[0005] The first object of the present invention is to provide a flexible reinforcement prefabricated assembly connection structure for realizing the connection between a prefabricated bridge pier and a pedestal. The prefabricated bridge pier is provided with a reserved longitudinal reinforcement connection section, and the pedestal is provided with a reserved vertical reinforcement connection section, including a reserved longitudinal reinforcement connection section, a reserved vertical reinforcement connection section, a reinforcement joint, and a flexible reinforcement. The reserved longitudinal reinforcement connection section is vertically aligned with the reserved vertical reinforcement connection section, and the flexible reinforcement is connected to the reserved longitudinal reinforcement connection section and the reserved vertical reinforcement connection section through a reinforcement joint.

[0006] In one embodiment of the present invention, the steel bar joint is welded or bolted to the reserved longitudinal reinforcement connection section or the reserved vertical reinforcement connection section.

[0007] In one embodiment of the present invention, when the steel bar joint is bolted to the reserved longitudinal reinforcement connection section, the inner diameter thread of the steel bar joint is the same as the outer diameter thread of the reserved longitudinal reinforcement connection section; the length of the threaded portion should be sufficient to ensure that no thread slippage occurs when the steel bar reaches the yield stress.

[0008] When the steel bar joint is bolted to the reserved vertical steel bar connection section, the inner diameter thread of the steel bar joint is the same as the outer diameter thread of the reserved vertical steel bar connection section; the length of the threaded part should be sufficient to ensure that no thread slippage occurs when the steel bar reaches the yield stress.

[0009] In one embodiment of the present invention, the steel bar joint includes a first joint and a second joint; the first joint is connected to a reserved longitudinal reinforcement connection section or a reserved vertical reinforcement connection section, and the second joint is connected to a flexible reinforcement.

[0010] In one embodiment of the present invention, the flexible ribs are selected from one or more of high-strength steel wire ropes, carbon fiber ropes, glass fiber ropes, basalt fiber ropes, or aramid fiber ropes. Compared with steel, they have higher tensile strength while meeting the flexibility requirement, so that the cross-sectional area of ​​the flexible ribs is smaller than that of the steel bars.

[0011] In one embodiment of the present invention, a single flexible bar connects a single reserved longitudinal bar connection section and a reserved vertical steel bar connection section, and the flexible bar is respectively connected to the second joint of the steel bar joint connected to the reserved longitudinal bar connection section and the reserved vertical steel bar connection section.

[0012] In one embodiment of the present invention, a single flexible bar connects multiple reserved longitudinal bar connection sections and reserved vertical steel bar connection sections, the flexible bar crosses through the second joint of the steel bar joint connected to the reserved longitudinal bar connection section and the reserved vertical steel bar connection section, and the ends of the flexible bar are connected by a flexible bar fastener.

[0013] In one embodiment of the present invention, when the flexible reinforcement is connected to a reserved longitudinal reinforcement connection section or a reserved vertical reinforcement connection section, the second joint is a cylindrical interface;

[0014] When the flexible reinforcement is connected to a plurality of reserved longitudinal reinforcement connection sections or reserved vertical reinforcement connection sections, the second joint is a semi-annular interface.

[0015] In one embodiment of the present invention, the flexible rib fastener comprises a flexible rib joint and a threaded sleeve; the threaded sleeve is arranged at both ends of the flexible rib joint.

[0016] In one embodiment of the present invention, the inner diameter thread of the flexible rib joint is the same as the outer diameter thread of the threaded sleeve.

[0017] In one embodiment of the present invention, a plurality of stirrups are arranged around the flexible ribs.

[0018] In one embodiment of the present invention, stirrups should be configured around the flexible bars to meet the shear resistance requirements and improve the compressive strength of the core area concrete. That is, a plurality of stirrups are arranged around the flexible bars, and the stirrups are selected from steel bars or flexible stirrups.

[0019] In one embodiment of the present invention, the diameter of the flexible reinforcement and the concrete strength grade in the connection area are determined according to the capacity protection design principle to ensure that the failure occurs at the pier body position above the connection area.

[0020] A second object of the present invention is to provide a construction method for the above-mentioned flexible reinforcement prefabricated assembly connection structure, comprising the following steps:

[0021] (S1) For prefabricated or cast-in-place caps with embedded vertical reinforcement, hoist the prefabricated pier or the lower segment of the prefabricated pier into place and align the reserved longitudinal reinforcement connection section with the reserved vertical reinforcement connection section;

[0022] (S2) connecting the flexible reinforcement to the reinforcement joint, and connecting the reinforcement joint to the reserved longitudinal reinforcement connection section and the reserved vertical reinforcement connection section;

[0023] (S3) Stirrups are tied around the flexible reinforcement, and the post-cast concrete in the connection area is cast and cured.

[0024] In one embodiment of the present invention, in step (S3), the concrete is selected from ordinary concrete, ultra-high performance concrete (UHPC) or high ductility concrete (ECC) having a compressive strength grade higher than that of the precast bridge pier.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] (1) The allowable error of the flexible reinforcement of the present invention during construction can be adjusted by the length of the flexible reinforcement and the length of the reinforcement joint, which greatly improves the construction tolerance of the connection structure. Since the flexible reinforcement has no pressure-bearing capacity, when the bridge pier is subjected to compression and bending, the compressive stress is entirely borne by the concrete in the connection area. Although the yield strength of the steel bar can reach more than 15 times the compressive strength of the concrete prism, the specification requires that the reinforcement ratio of the longitudinal reinforcement of the piers of highway bridges be within 0.6%-4%, and the compressive bearing capacity of the cross section of the reinforced concrete column is still mainly borne by the concrete. By increasing the strength grade of the concrete in the connection area, the purpose of making the compressive and bending bearing capacity of the connection area greater than the pier body can be achieved; at the same time, the cost of increasing the concrete strength by one strength grade increases by about 50-100 yuan / m3 (It may vary slightly depending on market conditions) and will not significantly increase the construction cost.

[0027] (2) The present invention connects the reserved longitudinal reinforcement connection section and the reserved vertical reinforcement connection section through flexible reinforcement, which can not only improve the construction tolerance, but also is simple in construction, easy to operate, highly economical, and easy to promote and apply. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a schematic diagram of a flexible reinforcement prefabricated assembly connection structure according to Example 1 of the present invention;

[0029] Figure 2 A schematic diagram of a prefabricated bridge pier provided with a reserved longitudinal reinforcement connection section according to the present invention;

[0030] Figure 3 A schematic diagram of a prefabricated cap with a reserved vertical steel bar connection section according to the present invention;

[0031] Figure 4 This is a schematic diagram of a steel bar joint according to Embodiment 1 of the present invention;

[0032] Figure 5 Schematic diagram of the flexible ribs of Example 1 of the present invention;

[0033] Figure 6 This is a schematic diagram of a flexible reinforcement prefabricated assembly connection structure according to Embodiment 2 of the present invention;

[0034] Figure 7 This is a schematic diagram of a steel bar joint according to Embodiment 2 of the present invention;

[0035] Figure 8 This is a schematic diagram of a flexible rib fastener according to Embodiment 2 of the present invention;

[0036] Numbers in the figure: 1. Prefabricated bridge pier; 2. Reserved longitudinal reinforcement connection section; 3. Steel bar joint; 4. Flexible reinforcement; 5. Reserved vertical reinforcement connection section; 6. Abutment; 7. Flexible reinforcement fastener; 8. Flexible reinforcement joint; 9. Threaded sleeve; 10. Stirrup. DETAILED DESCRIPTION

[0037] The present invention provides a flexible reinforcement prefabricated assembly connection structure, which is used to realize the connection between a prefabricated bridge pier and a pedestal. The prefabricated bridge pier is provided with a reserved longitudinal reinforcement connection section, and the pedestal is provided with a reserved vertical reinforcement connection section, which includes a reserved longitudinal reinforcement connection section, a reserved vertical reinforcement connection section, a reinforcement joint, and a flexible reinforcement. The reserved longitudinal reinforcement connection section is vertically aligned with the reserved vertical reinforcement connection section, and the flexible reinforcement is connected to the reserved longitudinal reinforcement connection section and the reserved vertical reinforcement connection section through a reinforcement joint.

[0038] In one embodiment of the present invention, the steel bar joint is welded or bolted to the reserved longitudinal reinforcement connection section or the reserved vertical reinforcement connection section.

[0039] In one embodiment of the present invention, when the steel bar joint is bolted to the reserved longitudinal reinforcement connection section, the inner diameter thread of the steel bar joint is the same as the outer diameter thread of the reserved longitudinal reinforcement connection section; the length of the threaded portion should be sufficient to ensure that no thread slippage occurs when the steel bar reaches the yield stress.

[0040] When the steel bar joint is bolted to the reserved vertical steel bar connection section, the inner diameter thread of the steel bar joint is the same as the outer diameter thread of the reserved vertical steel bar connection section; the length of the threaded part should be sufficient to ensure that no thread slippage occurs when the steel bar reaches the yield stress.

[0041] In one embodiment of the present invention, the steel bar joint includes a first joint and a second joint; the first joint is connected to a reserved longitudinal reinforcement connection section or a reserved vertical reinforcement connection section, and the second joint is connected to a flexible reinforcement.

[0042] In one embodiment of the present invention, the flexible ribs are selected from one or more of high-strength steel wire ropes, carbon fiber ropes, glass fiber ropes, basalt fiber ropes, or aramid fiber ropes. Compared with steel, they have higher tensile strength while meeting the flexibility requirement, so that the cross-sectional area of ​​the flexible ribs is smaller than that of the steel bars.

[0043] In one embodiment of the present invention, a single flexible bar connects a single reserved longitudinal bar connection section and a reserved vertical steel bar connection section, and the flexible bar is respectively connected to the second joint of the steel bar joint connected to the reserved longitudinal bar connection section and the reserved vertical steel bar connection section.

[0044] In one embodiment of the present invention, a single flexible bar connects multiple reserved longitudinal bar connection sections and reserved vertical steel bar connection sections, the flexible bar crosses through the second joint of the steel bar joint connected to the reserved longitudinal bar connection section and the reserved vertical steel bar connection section, and the ends of the flexible bar are connected by a flexible bar fastener.

[0045] In one embodiment of the present invention, when the flexible reinforcement is connected to a reserved longitudinal reinforcement connection section or a reserved vertical reinforcement connection section, the second joint is a cylindrical interface;

[0046] When the flexible reinforcement is connected to a plurality of reserved longitudinal reinforcement connection sections or reserved vertical reinforcement connection sections, the second joint is a semi-annular interface.

[0047] In one embodiment of the present invention, the flexible rib fastener comprises a flexible rib joint and a threaded sleeve; the threaded sleeve is arranged at both ends of the flexible rib joint.

[0048] In one embodiment of the present invention, the inner diameter thread of the flexible rib joint is the same as the outer diameter thread of the threaded sleeve.

[0049] In one embodiment of the present invention, a plurality of stirrups are arranged around the flexible ribs.

[0050] In one embodiment of the present invention, stirrups should be configured around the flexible bars to meet the shear resistance requirements and improve the compressive strength of the core area concrete. That is, a plurality of stirrups are arranged around the flexible bars, and the stirrups are selected from steel bars or flexible stirrups.

[0051] In one embodiment of the present invention, the diameter of the flexible reinforcement and the concrete strength grade in the connection area are determined according to the capacity protection design principle to ensure that the failure occurs at the pier body position above the connection area.

[0052] The present invention provides a construction method of the above-mentioned flexible reinforcement prefabricated assembly connection structure, comprising the following steps:

[0053] (S1) For prefabricated or cast-in-place caps with embedded vertical reinforcement, hoist the prefabricated pier or the lower segment of the prefabricated pier into place and align the reserved longitudinal reinforcement connection section with the reserved vertical reinforcement connection section;

[0054] (S2) connecting the flexible reinforcement to the reinforcement joint, and connecting the reinforcement joint to the reserved longitudinal reinforcement connection section and the reserved vertical reinforcement connection section;

[0055] (S3) Stirrups are tied around the flexible reinforcement, and the post-cast concrete in the connection area is cast and cured.

[0056] In one embodiment of the present invention, in step (S3), the concrete is selected from ordinary concrete, ultra-high performance concrete (UHPC) or high ductility concrete (ECC) having a compressive strength grade higher than that of the precast bridge pier.

[0057] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0058] Example 1

[0059] This embodiment provides a flexible rib prefabricated assembly connection structure.

[0060] This embodiment proposes a flexible reinforcement prefabricated assembly connection structure, such as Figure 1-5 As shown, it includes a reserved longitudinal reinforcement connection section 2, a reserved vertical reinforcement connection section 5, a reinforcement joint 3, and a flexible reinforcement 4. The reserved longitudinal reinforcement connection section 2 is vertically aligned with the reserved vertical reinforcement connection section 5, and the flexible reinforcement 4 is connected to the reserved longitudinal reinforcement connection section 2 and the reserved vertical reinforcement connection section 5 through the reinforcement joint 3.

[0061] The steel bar joint 3 includes a first joint and a second joint, the first joint and the second joint are cylindrical joints with different diameters, respectively, wherein the diameter of the first joint is larger than the diameter of the second joint; the first joint is connected to the reserved longitudinal reinforcement connection section 2 or the reserved vertical reinforcement connection section 5, and the second joint is connected to the flexible reinforcement 4; wherein the inner diameter thread of the first joint of the steel bar joint 3 is the same as the outer diameter thread of the reserved longitudinal reinforcement connection section 2 and the reserved vertical reinforcement connection section 5; the flexible reinforcement 4 is selected from high-strength steel wire ropes, and each flexible reinforcement 4 is respectively connected to a reserved longitudinal reinforcement connection section 2 and a reserved vertical reinforcement connection section 5; and three flexible stirrups are arranged on the periphery of the flexible reinforcement 4.

[0062] Example 2

[0063] This embodiment provides a construction method for a flexible reinforcement prefabricated assembly connection structure.

[0064] In an embodiment of the present invention, a construction method of a flexible reinforcement prefabricated assembly connection structure (embodiment 1) comprises the following steps:

[0065] (1) Prefabricate or cast-in-place abutment 6 with embedded vertical steel bars, hoist the prefabricated pier 1 into place, and align the reserved longitudinal reinforcement connection section 2 on the prefabricated pier with the reserved vertical reinforcement connection section 5 on the abutment;

[0066] (2) Connect the flexible bar 4 to the second joint of the steel bar joint 3, and thread the first joint of the steel bar joint 3 with the reserved longitudinal bar connection section 2 and the reserved vertical steel bar connection section 5, and tighten the steel bar joint 3;

[0067] (3) Tie three flexible stirrups around the flexible reinforcement 4, and cast the post-cast concrete in the connection area with formwork, and maintain for 28 days.

[0068] In the embodiment of the present invention, the preparation before construction is as follows: according to the design drawings, the construction site is cleaned up, and the construction materials, machinery, and personnel are arranged in place.

[0069] Example 3

[0070] This embodiment provides a flexible rib prefabricated assembly connection structure.

[0071] Compared with the embodiment 1, most of them are the same, except that in this embodiment, each flexible bar 4 is connected with a plurality of reserved longitudinal bar connection sections, specifically: Figure 6-8As shown, the steel bar joint 3 includes a first joint and a second joint, the first joint is a cylindrical joint, and the second joint is a semi-circular joint, the first joint is connected to the reserved longitudinal reinforcement connection section 2 or the reserved vertical reinforcement connection section 5; the flexible reinforcement 4 passes through the second joint and is connected to multiple reserved longitudinal reinforcement connection sections 2 and reserved vertical reinforcement connection sections 5, forming a cross grid shape, and the ends of the flexible reinforcement 4 are connected by a flexible reinforcement fastener 7; the flexible reinforcement fastener 7 includes a flexible reinforcement joint 8 and a threaded sleeve 9, and the threaded sleeve 9 is arranged at both ends of the flexible reinforcement joint 8; the inner diameter thread of the flexible reinforcement joint 8 is the same as the outer diameter thread of the threaded sleeve 9.

[0072] Since there are two flexible bars 4 branches under each reserved longitudinal reinforcement connection section 2, the cross-sectional area of ​​the flexible bars 4 can be smaller. At the same time, the reduction in the number of flexible bars 4 can speed up the construction speed.

[0073] Example 4

[0074] This embodiment provides a construction method for a flexible reinforcement prefabricated assembly connection structure.

[0075] In an embodiment of the present invention, a construction method of a flexible reinforcement prefabricated assembly connection structure (embodiment 3) comprises the following steps:

[0076] (1) Prefabricated or cast-in-place cap 6 with embedded vertical reinforcement, hoist the prefabricated pier 1 into place, and align the reserved longitudinal reinforcement connection section 2 with the reserved vertical reinforcement connection section 5.

[0077] (2) After the steel bar joint 3 is threadedly connected to the reserved longitudinal bar connection section 2 and the reserved vertical steel bar connection section 5, the flexible bar 4 is connected to the steel bar joint 3, and the flexible bar 4 is tightened by the flexible bar fastener 7.

[0078] (3) Tie three flexible stirrups around the flexible reinforcement 4, and cast the post-cast concrete in the connection area with formwork, and maintain for 28 days.

[0079] In the embodiment of the present invention, the preparation before construction is as follows: according to the design drawings, the construction site is cleaned up, and the construction materials, machinery, and personnel are arranged in place.

[0080] The above description of the embodiments is to facilitate the understanding and use of the invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the scope of protection of the present invention.

Claims

1. A flexible reinforcement prefabricated assembly connection structure, used to achieve the connection between a prefabricated bridge pier (1) and a cap (6), wherein the prefabricated bridge pier (1) is provided with a reserved longitudinal reinforcement connection section (2), and the cap (6) is provided with a reserved vertical reinforcement connection section (5), characterized in that: It comprises a reserved longitudinal reinforcement connection section (2), a reserved vertical reinforcement connection section (5), a reinforcement joint (3), and a flexible reinforcement (4), wherein the reserved longitudinal reinforcement connection section (2) is vertically aligned with the reserved vertical reinforcement connection section (5), and the flexible reinforcement (4) is connected to the reserved longitudinal reinforcement connection section (2) and the reserved vertical reinforcement connection section (5) via the reinforcement joint (3); The steel bar joint (3) comprises a first joint and a second joint; the first joint is connected to a reserved longitudinal steel bar connection section (2) or a reserved vertical steel bar connection section (5), and the second joint is connected to a flexible bar (4); A single flexible bar (4) connects a plurality of reserved longitudinal bar connection sections (2) and reserved vertical steel bar connection sections (5); the flexible bar (4) crosses and passes through a second joint of a steel bar joint (3) connected to the reserved longitudinal bar connection section (2) and the reserved vertical steel bar connection section (5); and the ends of the flexible bar (4) are connected via a flexible bar fastener (7); A plurality of stirrups (10) are arranged on the periphery of the flexible rib (4).

2. A flexible rib prefabricated assembly connection structure according to claim 1, characterized in that: The steel bar joint (3) is connected to the reserved longitudinal steel bar connection section (2) or the reserved vertical steel bar connection section (5) by welding or bolting.

3. A flexible rib prefabricated assembly connection structure according to claim 2, characterized in that: When the steel bar joint (3) is bolted to the reserved longitudinal bar connection section (2), the inner diameter thread of the steel bar joint (3) is the same as the outer diameter thread of the reserved longitudinal bar connection section (2); When the steel bar joint (3) is bolted to the reserved vertical steel bar connection section (5), the inner diameter thread of the steel bar joint (3) is the same as the outer diameter thread of the reserved vertical steel bar connection section (5).

4. The flexible rib prefabricated assembly connection structure according to claim 1, characterized in that: The flexible rib fastener (7) comprises a flexible rib joint (8) and a threaded sleeve (9); the threaded sleeve (9) is arranged at both ends of the flexible rib joint (8).

5. The flexible reinforcement prefabricated assembly connection structure according to claim 4, characterized in that: The inner diameter thread of the flexible rib joint (8) is the same as the outer diameter thread of the threaded sleeve (9).

6. A construction method for a flexible reinforcement prefabricated assembly connection structure as claimed in any one of claims 1 to 5, characterized in that: The following steps are involved: (S1) prefabricating or casting a cap (6) with embedded vertical reinforcement, hoisting the prefabricated bridge pier (1) or the lower segment of the prefabricated bridge pier (1) into place, and aligning the reserved longitudinal reinforcement connection section (2) and the reserved vertical reinforcement connection section (5); (S2) connecting the flexible reinforcement (4) to the reinforcement joint (3), and connecting the reinforcement joint (3) to the reserved longitudinal reinforcement connection section (2) and the reserved vertical reinforcement connection section (5); (S3) Stirrups (10) are tied around the flexible reinforcement (4) and post-cast concrete is cast in the connection area for curing.

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