A connection structure and method of prefabricated cylinder and pile foundation

Abstract

The invention discloses a connection structure and method of a prefabricated cylinder and a pile foundation, comprising two pile foundations arranged opposite to each other, wherein the top of the pile foundation is connected to the prefabricated cylinder, and the prefabricated cylinders at the tops of the two pile foundations are connected by a cast-in-place tie beam; a groove is arranged on the top of the pile foundation, a tenon is arranged on the bottom of the prefabricated cylinder, the tenon is embedded in the groove, a first steel corrugated pipe is arranged on the side of the groove, a second steel corrugated pipe is sleeved on the outer side of the bottom of the tenon, and a grouting casting part is arranged between the first steel corrugated pipe and the second steel corrugated pipe.

Description

Technical Field

[0001] The invention belongs to the technical field of bridges, and in particular relates to a connection structure and method of a prefabricated column and a pile foundation. Background Art

[0002] The statements herein merely provide background information related to the present invention and do not necessarily constitute prior art.

[0003] Prefabricated construction is widely used in the construction field. Its outstanding advantage is that it can greatly save construction time and improve construction quality. Due to the strip-shaped distribution of highway projects and the fact that most of the work sites are outdoors, prefabricated assembly construction of the lower part of the bridge has not been widely used in highway projects.

[0004] In recent years, some projects have explored the application of prefabricated assembly of bridge substructures. In these engineering applications, there are many ways to connect prefabricated piers with cast-in-place foundations, but the inventors found that these methods have the disadvantages of long joint construction time, long temporary support system occupancy time, the need to increase the size of components or pouring operation platforms at the joints, and the lack of sufficient experimental and theoretical research support for the reliability of the connection method. Summary of the invention

[0005] In view of the deficiencies in the prior art, the purpose of the present invention is to provide a connection structure and method for a prefabricated column and a pile foundation, in which a strong connection is achieved between the column and the pile foundation through a steel corrugated pipe and a grouting casting, thereby ensuring the reliability of the pile-column connection.

[0006] In order to achieve the above object, the present invention is implemented through the following technical solutions:

[0007] In the first aspect, an embodiment of the present invention provides a connection structure between a prefabricated column and a pile foundation, comprising two oppositely arranged pile foundations, the top of the pile foundation is connected to the prefabricated cylinder, and the prefabricated cylinders at the top of the two pile foundations are connected by a cast-in-place tie beam; a groove is arranged on the top of the pile foundation, a tenon is arranged on the bottom of the prefabricated cylinder, the tenon is embedded in the groove, a first steel corrugated pipe is arranged on the side of the groove, a second steel corrugated pipe is sleeved on the outer side of the bottom of the tenon, and a grouting casting is arranged between the first steel bellows and the second steel bellows.

[0008] As a further technical solution, pile foundation main reinforcement is vertically arranged in the pile foundation, column main reinforcement is vertically arranged in the prefabricated column, and the column main reinforcement and the pile foundation main reinforcement are fixedly connected.

[0009] As a further technical solution, an extension end is arranged at the top of the pile foundation main reinforcement, the extension end extends out of the top of the pile foundation, the extension end of the pile foundation main reinforcement is arranged obliquely, and the top end of the pile foundation main reinforcement is arranged close to the pile foundation axis relative to the bottom end.

[0010] As a further technical solution, an extension end is set at the bottom of the cylindrical main reinforcement, the extension end extends out of the bottom of the prefabricated cylinder, the extension end of the cylindrical main reinforcement is set at an angle, and the bottom end of the cylindrical main reinforcement is set away from the pile foundation axis relative to the top end.

[0011] As a further technical solution, a steel pad is arranged between the groove at the top of the pile foundation and the bottom end of the tenon of the prefabricated column.

[0012] As a further technical solution, a steel cage is arranged in the tenon of the prefabricated column.

[0013] As a further technical solution, a steel mesh is arranged at the bottom end of the tenon.

[0014] As a further technical solution, a plurality of reserved holes are provided on the peripheral side of the tenon of the prefabricated cylinder, and PVC pipes are arranged in the reserved holes.

[0015] As a further technical solution, the length of the tenon is greater than the depth of the groove, and a post-cast concrete member is arranged between the outer side of the tenon and the top of the pile foundation.

[0016] In a second aspect, an embodiment of the present invention further provides a method for connecting a prefabricated cylinder and a pile foundation, comprising the following steps:

[0017] The pile foundation is formed by pouring, a groove is opened at the top of the pile foundation, a first steel corrugated pipe is arranged on the side of the groove, and main reinforcement of the pile foundation is arranged in the pile foundation, and the main reinforcement of the pile foundation extends out of the top of the pile foundation;

[0018] Prefabricate the prefabricated cylinder, arrange a second steel corrugated pipe outside the bottom of the tenon of the prefabricated cylinder, arrange a steel cage in the tenon, arrange a steel mesh at the end of the tenon, open a reserved hole around the tenon, arrange the main steel bar in the prefabricated cylinder, and extend the main steel bar out of the bottom of the prefabricated cylinder;

[0019] Place a steel pad in the groove, hoist the prefabricated cylinder so that the tenon is embedded in the groove, and set a jack support system at the reserved hole on the side of the prefabricated cylinder to adjust the verticality of the prefabricated cylinder;

[0020] Pour high-strength non-shrinkage grouting material into the gap between the groove and the tenon, evacuate the lifting equipment and jack support system, weld the pile foundation main reinforcement and column main reinforcement, pour post-pour concrete between the precast column and the pile foundation, and pour cast-in-place tie beams between the relatively set precast columns.

[0021] The beneficial effects of the above embodiments of the present invention are as follows:

[0022] The connection structure of the present invention is provided with a groove on the pile foundation and a tenon on the column, the tenon and the groove are embedded, and a steel corrugated pipe is provided at the connection between the pile foundation and the column, and grouting material is poured, so that the temporary fixation of the column can be realized reliably and quickly, the construction period is greatly shortened, and the time cost and material cost of the temporary fixing structure system are reduced.

[0023] In the connection structure of the present invention, the pile foundation and the column are finally connected by welding the main reinforcement, which can reliably achieve a strong connection between the pile foundation and the column and improve the reliability of the pile-column connection.

[0024] The connection method of the present invention enables assembly construction between the cylinder and the pile foundation. Compared with the cast-in-situ construction method, it can greatly shorten the construction period, improve the construction quality of the components, reduce environmental pollution, and eliminate the danger of high-support construction on site.

[0025] The connection method of the present invention adopts a large-diameter corrugated pipe grouting method to serve as a short-term support in the construction stage. The grouting material has good workability and early strength, which shortens the occupation time of the hoisting equipment and the jack.

[0026] The connection method of the present invention realizes a strong connection between the column and the pile foundation through the main reinforcement, which is no different from cast-in-place construction in mechanical analysis. Mechanical calculations can be performed completely according to existing theories, and project acceptance can be carried out according to existing specifications. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0028] Figure 1 is a schematic diagram of a connection structure between a column and a pile foundation according to one or more embodiments of the present invention;

[0029] Figure 2 is a schematic diagram of a pile foundation according to one or more embodiments of the present invention;

[0030] Figure 3 is a schematic diagram of a prefabricated cylinder according to one or more embodiments of the present invention;

[0031] Figure 4 is a schematic diagram of using a jack support system to fine-tune the verticality of a column in a method for connecting a column to a pile foundation according to one or more embodiments of the present invention;

[0032] Figure 5 is a schematic diagram of a jack support system according to one or more embodiments of the present invention;

[0033] In the figure: 1-pile foundation; 2-precast column; 3-grouting casting; 4-post-cast concrete part; 5-cast-in-place tie beam; 6-pile foundation main reinforcement; 7-column main reinforcement; 8-tenon longitudinal reinforcement; 9-steel corrugated pipe; 10-steel corrugated pipe; 11-steel mesh; 12-steel pad; 13-PVC pipe; 14-jack; 15-20b I-beam; 16-φ40 steel bar, 17 groove, 18 tenon.

[0034] In order to show the positions of various parts, the distances or sizes between them are exaggerated and the schematic diagram is for reference only. DETAILED DESCRIPTION

[0035] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used in the present invention have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0036] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present invention. As used herein, unless otherwise explicitly stated in the present invention, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "include" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof;

[0037] For the convenience of description, if the words "up", "down", "left" and "right" appear in the present invention, they only indicate that they are consistent with the up, down, left and right directions of the drawings themselves, and do not limit the structure. They are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the present invention.

[0038] Terminology explanation section: If the terms "install", "connect", "connect", "fixed" and the like appear in the present invention, they should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be an internal connection between two elements, or an interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0039] As introduced in the background technology, there are deficiencies in the prior art. In order to solve the above technical problems, the present invention proposes a connection structure and method between a prefabricated cylinder and a pile foundation.

[0040] In a typical embodiment of the present invention, Figure 1As shown, a connection structure between a prefabricated column and a pile foundation is provided, comprising two oppositely arranged pile foundations 1, the pile foundations are formed by in-situ pouring, the top of the pile foundation 1 is connected to the prefabricated column 2, and the prefabricated columns 2 at the top of the two pile foundations are connected by a cast-in-situ tie beam 5.

[0041] Prefabricated columns are circular piers.

[0042] A pile foundation main reinforcement 6 is vertically arranged inside the pile foundation 1, and an extension end is arranged on the top of the pile foundation main reinforcement 6, which extends out of the top of the pile foundation 1. The extension end of the pile foundation main reinforcement is inclined, and the top end of the pile foundation main reinforcement is arranged close to the pile foundation axis relative to the bottom end.

[0043] A groove is provided on the top of the pile foundation 1, such as Figure 2 As shown, the groove has a set depth, a steel bellows 9 is arranged inside the groove, a grouting casting 3 is arranged on the inner wall of the steel bellows 9, and the grouting casting 3 is cast by high-strength non-shrinkage grouting material.

[0044] A cylindrical main reinforcement 7 is vertically arranged inside the prefabricated cylinder 2, and an extension end is arranged at the bottom of the cylindrical main reinforcement 7, which extends out of the bottom of the prefabricated cylinder. The extension end of the cylindrical main reinforcement is inclined, and the bottom end of the cylindrical main reinforcement is arranged away from the pile foundation axis relative to the top end.

[0045] The cylindrical main reinforcement 7 and the pile foundation main reinforcement 6 are fixedly connected, and in this embodiment, the two are fixedly connected by welding. Specifically, the cylindrical main reinforcement 7 and the extended ends of the pile foundation main reinforcement 6 are welded and connected.

[0046] A tenon is provided at the bottom of the prefabricated cylinder 2, and the tenon is embedded in the groove of the pile foundation 1. A steel bellows 10 is sleeved on the outside of the bottom of the tenon. The steel bellows 10 has the same structure as the steel bellows 9. The outer wall of the steel bellows 10 is connected to the grouting casting part 3. During the specific implementation, grouting material is poured between the steel bellows 10 and the steel bellows 9 to form a grouting casting part.

[0047] A steel pad 12 is arranged between the groove at the top of the pile foundation 1 and the bottom end of the tenon of the prefabricated column 2 .

[0048] A steel cage is arranged in the tenon of the prefabricated cylinder 2, and the steel cage consists of the tenon longitudinal reinforcement 8 and spiral stirrups. The tenon longitudinal reinforcement 8 is arranged vertically, and the spiral stirrups are arranged between the tenon longitudinal reinforcements; a steel mesh 11 is arranged at the bottom end of the tenon, and the specifications of the steel mesh meet the requirements of the design specifications for local pressure-bearing members. In this embodiment, four layers of D10 steel mesh are used, and the vertical spacing of the mesh is 8 cm.

[0049] A plurality of reserved holes are provided on the periphery of the tenon of the prefabricated cylinder 2, and PVC pipes 13 are arranged in the reserved holes.

[0050] The length of the tenon of the prefabricated column is greater than the depth of the pile foundation groove. A post-cast concrete member 4 is arranged between the outer side of the prefabricated column tenon and the top of the pile foundation. The post-cast concrete member 4 and the cast-in-place tie beam 5 are both cast-in-place reinforced concrete.

[0051] The present invention arranges a steel corrugated pipe at the connection between the pile foundation and the column, injects grouting material, and connects the column and the pile foundation with main reinforcement, thereby reliably realizing a strong connection between the pile foundation and the column and ensuring the reliability and acceptability of the pile-column connection.

[0052] The present invention also proposes a method for connecting a prefabricated cylinder and a pile foundation, and the specific steps are as follows:

[0053] Cast-in-place pile foundation according to design drawings 1;

[0054] After the poured pile foundation concrete reaches the designed strength, the pile head is broken down to h1+h2 below the designed elevation of the pile top, exposing the fresh contact surface and forming a groove; a steel formwork is set up on site, the steel corrugated pipe 9 inside the groove and the designed stirrups of the pile foundation are arranged, and concrete is poured to h1 below the pile top elevation. Figure 2 As shown;

[0055] While the pile foundation 1 is being constructed, the prefabrication and curing of the prefabricated cylinder 2 are completed in the prefabrication yard. Note that the prefabricated cylinder tenon end should be roughened within the length range h1. The value of h1 is the height of the tie beam. When there is no tie beam, it should not be less than 20 times the diameter of the main reinforcement 7 of the cylinder. A steel corrugated pipe 10 is set within the length range h2. h2 can be half of the cylinder diameter D1. A steel cage needs to be arranged inside the tenon. The steel cage consists of the longitudinal reinforcement 8 of the tenon and spiral stirrups. The steel cage extends upward for a length h3 that is not less than the standard anchorage length of the longitudinal reinforcement 8 of the tenon. Four layers of steel mesh 11 are set at the end of the tenon. The specifications of the steel mesh meet the requirements of the design specifications for local pressure-bearing components. Four layers of D10 steel mesh can be used, and the vertical spacing of the mesh is 8cm. Four jack support positions are evenly arranged around the tenon. Two upper and lower holes are reserved at each location with a φ50 PVC pipe 13.

[0056] Transporting the prefabricated prefabricated cylinder 2 to the construction site;

[0057] Place a D200*20mm round steel pad 12 at the center of the pile foundation groove; hoist the prefabricated cylinder 2 so that the tenon is inserted into the pile foundation groove, and adjust the plane position of the pier column according to the marked line; place four jacks around the prefabricated cylinder to fine-tune the verticality of the prefabricated cylinder to meet the requirements of relevant acceptance regulations; the temporary support system composed of four jacks consists of jacks 14, 20b I-beams 15 and φ40 steel bars 16, among which the φ40 steel bars are inserted into the PVC pipe 13 of the reserved hole of the prefabricated cylinder 2, and the 20b I-beams 15 and the φ40 steel bars are welded to form a support skeleton; Pour high-strength non-shrinkage grouting material into the gap between the groove and the prefabricated cylindrical tenon; after the strength of the grouting material reaches 40MPa, remove the hoisting equipment of the prefabricated column 2 and the four jacks at the bottom of the column; seal the eight holes reserved on the cylindrical tenon with grouting material; weld the pile foundation main reinforcement 6 and the cylindrical main reinforcement 7, using single-sided welding, and the welding length is not less than 10d; arrange the connecting section stirrups and tie beam steel bars (if any), support the formwork to cast the post-cast concrete and cast-in-place tie beam 5, and use a small-diameter vibrator to vibrate and compact them; cure the post-cast concrete (the strength of the post-cast concrete is consistent with the requirements of the column), and when it reaches the designed strength, remove the formwork and fill the soil to restore the original ground line.

[0058] The connection method of the present invention enables the application of prefabricated construction of bridge piers in engineering projects. Compared with the cast-in-place construction method, prefabricated construction shortens the construction time of pile-column joints, can greatly shorten the construction period, improve the construction quality of components, and at the same time reduce environmental pollution and eliminate the danger of on-site high-support construction.

[0059] The large-diameter bellows grouting method is used as a short-term support during the construction phase. The grouting material has good workability and early strength, which shortens the occupation time of the lifting equipment and jacks. The large-diameter bellows grouting method is only used for short-term support during the construction phase. Compared with the traditional socket-type connection method, it can save at least 50% of high-strength grouting materials, reduce the cost, reduce the amount of special materials, and improve economic efficiency.

[0060] The present invention is applied to pile-column bridge piers commonly used in highway bridges. It does not need to change the size of components or specially cast operating platforms such as small caps to achieve connection. It maintains the same external dimensions as the cast-in-place solution, which ensures beauty and saves materials.

[0061] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A connection structure between a prefabricated column and a pile foundation, characterized in that: It comprises two pile foundations arranged opposite to each other, the top of the pile foundation is connected to the prefabricated cylinder, and the prefabricated cylinders at the top of the two pile foundations are connected by a cast-in-place tie beam; a groove is arranged on the top of the pile foundation, a tenon is arranged on the bottom of the prefabricated cylinder, the tenon is embedded in the groove, a first steel corrugated pipe is arranged on the side of the groove, a second steel corrugated pipe is sleeved on the outer side of the bottom of the tenon, and a grouting casting is arranged between the first steel corrugated pipe and the second steel corrugated pipe; A plurality of reserved holes are provided on the circumferential side of the tenon of the prefabricated cylinder, and PVC pipes are arranged in the reserved holes; A steel cage is arranged in the tenon of the prefabricated column. The steel cage is composed of the longitudinal reinforcement of the tenon and spiral stirrups. The longitudinal reinforcement of the tenon is arranged vertically, and the spiral stirrups are arranged between the longitudinal reinforcement of the tenon. A steel mesh is arranged at the bottom end of the tenon. The specifications of the steel mesh meet the requirements of the design specifications for local pressure-bearing components. A jack support system is arranged at the reserved holes on the circumference of the prefabricated cylinder to adjust the verticality of the prefabricated cylinder.

2. The connection structure between the prefabricated column and the pile foundation as claimed in claim 1 is characterized in that: The pile foundation main reinforcement is vertically arranged in the pile foundation, and the prefabricated cylinder main reinforcement is vertically arranged in the prefabricated cylinder. The cylinder main reinforcement and the pile foundation main reinforcement are fixedly connected.

3. The connection structure between the prefabricated column and the pile foundation as claimed in claim 2 is characterized in that: An extension end is arranged at the top of the pile foundation main reinforcement, the extension end extends out of the top of the pile foundation, the extension end of the pile foundation main reinforcement is arranged obliquely, and the top end of the pile foundation main reinforcement is arranged close to the pile foundation axis relative to the bottom end.

4. The connection structure between the prefabricated column and the pile foundation as claimed in claim 2 is characterized in that: An extension end is arranged at the bottom of the cylindrical main reinforcement, and the extension end extends out of the bottom of the prefabricated cylinder. The extension end of the cylindrical main reinforcement is arranged obliquely, and the bottom end of the cylindrical main reinforcement is arranged away from the pile foundation axis relative to the top end.

5. The connection structure between the prefabricated column and the pile foundation as claimed in claim 1 is characterized in that: A steel pad is arranged between the groove at the top of the pile foundation and the bottom end of the tenon of the prefabricated column.

6. The connection structure of the prefabricated column and the pile foundation as claimed in claim 1 is characterized in that: The length of the tenon is greater than the depth of the groove, and a post-cast concrete piece is arranged between the outer side of the tenon and the top of the pile foundation.

7. A method for connecting a prefabricated column and a pile foundation, using the connection structure of the prefabricated column and the pile foundation as claimed in any one of claims 1 to 6, characterized in that: The following steps are involved: The pile foundation is formed by pouring, a groove is opened at the top of the pile foundation, a first steel corrugated pipe is arranged on the side of the groove, and the main reinforcement of the pile foundation is arranged in the pile foundation, and the main reinforcement of the pile foundation extends out of the top of the pile foundation; Prefabricate the prefabricated cylinder, arrange a second steel corrugated pipe outside the bottom of the tenon of the prefabricated cylinder, arrange a steel cage in the tenon, arrange a steel mesh at the end of the tenon, open a reserved hole around the tenon, arrange the main steel bar in the prefabricated cylinder, and extend the main steel bar out of the bottom of the prefabricated cylinder; Place a steel pad in the groove, hoist the prefabricated cylinder so that the tenon is embedded in the groove, and set a jack support system at the reserved hole on the side of the prefabricated cylinder to adjust the verticality of the prefabricated cylinder; Pour high-strength non-shrinkage grouting material into the gap between the groove and the tenon, evacuate the lifting equipment and jack support system, weld the pile foundation main reinforcement and column main reinforcement, pour post-pour concrete between the precast column and the pile foundation, and pour cast-in-place tie beams between the relatively set precast columns.

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