A new type of precast capping beam and its construction method

Abstract

The present invention provides a novel precast capping beam and its construction method. The main body of the precast capping beam is formed by pouring concrete into a steel reinforcement cage and is used to be arranged on bridge pipe piles. Two pipe pile embedding grooves are spaced apart on the interface between the precast capping beam and the bridge pipe piles. The two pipe pile embedding grooves are spaced along the width direction of the precast capping beam. The horizontal cross-sectional dimension of each pipe pile embedding groove is not less than the horizontal cross-sectional dimension of the bridge pipe pile. A grouting hole and a slurry outlet hole are spaced apart on each pipe pile embedding groove. Both the grouting hole and the slurry outlet hole extend from the pipe pile embedding groove to the side surface of the precast capping beam, and both are at the same horizontal height as the bottom of the pipe pile embedding groove. A bearing template is sleeved on the upper part of the bridge pipe pile. The distance from the top surface of the bearing template to the top of the bridge pipe pile is equal to the depth of the pipe pile embedding groove. A template grouting hole is opened in the lower part of the bearing template. Based on the above precast capping beam, a construction method is proposed, thus realizing the rapid installation of the assembled bridge capping beam.

Description

Technical Field

[0001] The present invention relates to the field of construction of prefabricated bridge substructures, and particularly to a novel precast capping beam and a construction method thereof. Background Art

[0002] With the development of the domestic transportation industry in recent years, the traffic pressure has been increasing day by day, and more and more prefabricated bridges with simple structures, convenient construction, and low prices have been applied. With the popularization of prefabricated bridges, the prefabricated construction technology in the bridge field has also been developing rapidly. With the in-depth research, the application scope of the prefabricated construction technology of bridges is no longer limited to the superstructure, and the practitioners in the bridge construction industry urgently hope that the components of the bridge substructure can be further standardized and the construction process can be simplified.

[0003] During the construction of the conventional prefabricated bridge substructure, the connection control between the precast capping beam and the bridge pier is a difficult point in the process. The common practice of this construction technology is to vertically open holes penetrating the top surface and the bottom surface at intervals at the connection part of the precast capping beam, and vertically sunk grooves corresponding to the vertical holes are arranged on the top surface of the precast pier column. Connecting steel bars extending into the corresponding vertical holes are arranged at intervals in each vertical sunk groove, and then high-strength and fast-setting filling materials are poured into the vertical sunk grooves and the vertical holes from the upper ports of the vertical holes to connect the precast capping beam and the precast pier column into one body. During the on-site implementation of this technology, the problem that the vertical holes of the capping beam cannot be aligned with the vertical sunk grooves of the pier column often occurs, resulting in the obstruction of the construction process.

[0004] To solve the above problems, the present invention proposes a novel precast capping beam and a construction method thereof to achieve the rapid installation of the capping beam of the prefabricated bridge. Summary of the Invention

[0005] To achieve the above object, the technical solution adopted by the present invention is:

[0006] A novel precast capping beam, the main body of which is formed by pouring concrete into a steel reinforcement cage and is used to be arranged on bridge pipe piles. Two pipe pile embedding grooves are arranged at intervals on the interface between the precast capping beam and the bridge pipe piles. The two pipe pile embedding grooves are arranged at intervals along the width direction of the precast capping beam. The horizontal cross-sectional dimension of each pipe pile embedding groove is not less than the horizontal cross-sectional dimension of the bridge pipe pile. Each pipe pile embedding groove is provided with a grouting hole and a slurry outlet hole at intervals. The grouting hole and the slurry outlet hole both extend from the pipe pile embedding groove to the side surface of the precast capping beam, and both of them are at the same horizontal height as the bottom of the pipe pile embedding groove. A pressure-bearing formwork is sleeved on the upper part of the bridge pipe pile. The distance from the top surface of the pressure-bearing formwork to the top of the bridge pipe pile is equal to the depth of the pipe pile embedding groove. The horizontal cross-sectional dimension of the pressure-bearing formwork is larger than the horizontal cross-sectional dimension of the pipe pile embedding groove. The lower part of the pressure-bearing formwork is provided with a formwork grouting hole.

[0007] Furthermore, assuming that the depth of the groove in which the pipe pile is embedded is H, Where V is the maximum design shear force transmitted by the bridge superstructure, d is the diameter of the bridge pile, and [σ] is the ultimate compressive strength of concrete.

[0008] Furthermore, assuming that the minimum distance between the pile embedded in the groove and the edge of the prefabricated cap beam is D, Where W is the weight of concrete, h is the distance from the bottom of the groove where the pile is embedded to the top of the precast cap beam, and r is the radius of the bridge pile. is the internal friction angle of concrete, The bonding strength of concrete.

[0009] Furthermore, the present invention also provides a construction method using the novel prefabricated cap beam described above, comprising the following steps:

[0010] (1) Install prefabricated pipe piles;

[0011] (2) Install the prefabricated cap beam by crane;

[0012] (3) Install the pressure formwork at the bottom of the prefabricated cap beam;

[0013] (4) Grouting from the grouting hole;

[0014] (5) When the grouting hole starts to flow out of the original concrete slurry, stop grouting and seal the grouting hole;

[0015] (6) Remove the pressure formwork after the concrete strength reaches 70% of the design strength;

[0016] (7) Complete the construction.

[0017] Furthermore, in step (4), high-strength concrete is injected through the template grouting holes on the pressure-bearing template, and the concrete grade should be higher than the concrete grade of the precast pipe piles.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1. A novel prefabricated cap beam proposed by the present invention has the characteristics of simple manufacture and easy installation;

[0020] 2. The present invention proposes a construction method based on a new type of prefabricated cap beam, which replaces the step of connecting steel bars and butting the sinking grooves in the existing cap beam installation method by mortise and tenon joints, thereby solving the problem of difficulty in butting the cap beam. At the same time, by grouting into the mortise, the butt strength between the cap beam and the pipe piles is ensured. The construction method has the advantages of simple steps and low construction difficulty. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a structural schematic diagram of the prefabricated cap beam of the present invention.

[0022] Figure 2 Schematic structural diagram during the installation of the precast capping beam.

[0023] Figure 3 is Figure 2 View in the A - A direction in

[0024] Description of main component symbols

[0025] In the figure: precast capping beam 1, pipe pile embedding groove 2, grouting hole 3, slurry outlet hole 4, precast pipe pile 5, bearing template 6. The following specific embodiments will further illustrate the present invention in conjunction with the above - mentioned drawings. Specific embodiments

[0026] Please refer to Figures 1 to 3 , in a preferred embodiment of the present invention, a new - type precast capping beam, the main body of which is formed by pouring concrete into a steel reinforcement cage and is used to be arranged on bridge pipe piles. On the interface between the precast capping beam 1 and the bridge pipe piles, two pipe pile embedding grooves 2 are arranged at intervals. The two pipe pile embedding grooves 2 are arranged at intervals along the width direction of the precast capping beam 1. The horizontal cross - sectional dimension of each pipe pile embedding groove 2 is not less than the horizontal cross - sectional dimension of the bridge pipe pile; on each pipe pile embedding groove 2, a grouting hole 3 and a slurry outlet hole 4 are arranged at intervals. Both the grouting hole 3 and the slurry outlet hole 4 extend from the pipe pile embedding groove 2 to the side of the precast capping beam 1, and both are at the same horizontal height as the bottom of the pipe pile embedding groove 2; a bearing template 6 is sleeved on the upper part of the bridge pipe pile. The distance from the top surface of the bearing template 6 to the top of the bridge pipe pile is equal to the depth of the pipe pile embedding groove 2. The horizontal cross - sectional dimension of the bearing template 6 is larger than the horizontal cross - sectional dimension of the pipe pile embedding groove 2. A template grouting hole is arranged at the lower part of the bearing template 6. The precast pipe pile 5 designed in the present invention is installed by a crane during construction, so that the precast pipe pile 5 is inserted into the pipe pile embedding groove 2. After insertion, the bearing template 6 is installed on the top of the precast pipe pile 5, and after installation, the bearing template 6 is fixedly installed at the bottom of the precast capping beam 1 with bolts, and then grouting is carried out through the template grouting hole on the bearing template 6, so that the precast pipe pile 5 is bonded to the precast capping beam 1. It should be noted that the position of the template grouting hole on the bearing template 6 needs to be opened according to the elevation after construction at the bottom of the precast capping beam 1. After grouting, this hole needs to be closed. At the same time, the slurry outlet hole 4 on the precast capping beam 1 also needs to be closed after grouting.

[0027] Furthermore, let the depth of the pipe pile embedding groove 2 be H, where V is the maximum designed shear force transmitted by the superstructure of the bridge, d is the diameter of the bridge pipe pile, and [σ] is the ultimate compressive strength of concrete.

[0028] Furthermore, let the minimum distance from the pipe pile embedding groove 2 to the edge of the precast capping beam 1 be D, Wherein, W is the unit weight of concrete, h is the distance from the bottom of the pipe pile embedded in the groove 2 to the top of the precast capping beam 1, r is the radius of the bridge pipe pile, is the internal friction angle of concrete, is the adhesive force of concrete.

[0029] Furthermore, the present invention also provides a construction method using the above-mentioned new precast capping beam 1, which includes the following steps:

[0030] (1) Install the precast pipe pile 5;

[0031] (2) Use a crane to install the precast capping beam 1;

[0032] (3) Install the bearing formwork 6 at the bottom of the precast capping beam 1; the top height of the bearing formwork 6 is the same as the designed elevation at the bottom of the precast capping beam 1, and its height is adjusted by the connection length between the bearing formwork 6 and the precast pipe pile 5, so as to realize the rapid installation of the precast capping beam 1;

[0033] (4) Grout from the grouting hole 3; specifically, high-strength concrete is injected through the formwork grouting hole on the bearing formwork 6, and the grade of the injected concrete should be higher than that of the precast pipe pile 5.

[0034] (5) Stop grouting and seal the grout outlet hole 4 after the grout outlet hole 4 starts to flow out the original concrete slurry;

[0035] (6) Remove the bearing formwork 6 after the concrete strength reaches 70% of the designed strength;

[0036] (7) Complete the construction.

[0037] The above description is a detailed description of the preferred feasible embodiments of the present invention, but the embodiments are not intended to limit the scope of the patent application of the present invention. Any equivalent changes or modifications made under the technical spirit disclosed by the present invention shall fall within the scope of the patent covered by the present invention.

Claims

1. A construction method using a new type of precast capping beam. The new type of precast capping beam is formed by casting concrete in a steel reinforcement cage and is used to be set on bridge pipe piles. It is characterized in that: On the interface between the precast capping beam and the bridge pipe pile, two pipe pile embedding grooves are arranged at intervals. The two pipe pile embedding grooves are arranged at intervals along the width direction of the precast capping beam. The horizontal cross-sectional dimension of each pipe pile embedding groove is not less than the horizontal cross-sectional dimension of the bridge pipe pile; on each pipe pile embedding groove, grouting holes and slurry outlet holes are arranged at intervals. The grouting holes and the slurry outlet holes both extend from the pipe pile embedding groove to the side surface of the precast capping beam, and both of them are at the same horizontal height as the bottom of the pipe pile embedding groove; a bearing template is sleeved on the upper part of the bridge pipe pile. The distance from the top surface of the bearing template to the top of the bridge pipe pile is equal to the depth of the pipe pile embedding groove. The horizontal cross-sectional dimension of the bearing template is larger than the horizontal cross-sectional dimension of the pipe pile embedding groove. A template grouting hole is opened at the lower part of the bearing template; The construction method includes the following steps: (1) Install precast pipe piles; (2) Use a crane to install the precast capping beam; (3) Install a bearing template at the bottom of the precast capping beam; (4) Inject high-strength concrete through the template grouting hole on the bearing template; (5) Stop grouting and seal the slurry outlet hole after the concrete raw slurry starts to flow out of the slurry outlet hole; (6) Remove the bearing template after the concrete strength reaches 70% of the design strength; (7) Complete the construction.

2. The construction method using a new type of precast capping beam according to claim 1, characterized in that: Let the groove depth of the pipe pile embedding groove be H. Wherein, V is the maximum design shear force transmitted by the superstructure of the bridge, d is the diameter of the bridge pipe pile, and [σ] is the ultimate compressive strength of the concrete.

3. The construction method using a new type of precast capping beam according to claim 1, characterized in that: Let the minimum distance from the embedded pipe pile in the groove to the edge of the precast capping beam be D. Wherein, W is the unit weight of concrete, h is the distance from the bottom of the groove where the pipe pile is embedded to the top of the precast capping beam, r is the radius of the bridge pipe pile. is the internal friction angle of concrete. is the adhesive force of concrete.

4. The construction method using a new type of precast capping beam according to claim 1, characterized in that: In step (4), high-strength concrete is injected through the template grouting hole on the bearing template, and the concrete grade should be higher than the concrete grade of the precast pipe pile.

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