Prefabricated pier column connecting joint for square single pile and construction method

Abstract

The invention discloses a prefabricated pier column connecting joint for a square single pile and a construction method, and belongs to the technical field of constructional engineering.The prefabricated pier column connecting joint comprises a pier column arranged in a square shape and a pile foundation fixedly connected with the pier column, the pier column is formed by pouring and prefabricating high-toughness concrete, and a plurality of erecting ribs are arranged in the pier column in an array mode; a plurality of erection ribs are bound and fixed with stirrups arranged side by side in the axial direction of the pier column, a prestressed steel strand is arranged in the middle in the pier column in an array mode, a plastic hinge area is arranged at the bottom of the pier column, energy dissipation steel bars are arranged in the plastic hinge area of the pier column, and a pile foundation expansion section coaxial with the pile foundation is arranged on the pile foundation. A steel sleeve is arranged on the outer surface of the pile foundation expansion section, and a socket section for a pier column to be inserted is arranged on the pile foundation expansion section. When an earthquake occurs, the prestressed steel strands in the square pier column can provide reset capacity, the residual displacement of the pier column is reduced, and the energy dissipation steel bars in the pier column can play a role in dissipating earthquake energy.

Description

Technical Field

[0001] The invention belongs to the technical field of construction engineering, and in particular relates to a prefabricated pier column connection node for a square single pile and a construction method. Background Art

[0002] Bridges are the hubs connecting cities and regions, and the rescue channels for post-earthquake rescue and disaster relief. If a bridge collapses or is seriously damaged in an earthquake, it will threaten the safety of pedestrians, vehicles and other traffic participants, and will also hinder rescue and reconstruction work in the disaster area, resulting in serious economic losses and casualties.

[0003] Most bridge piers in the world are reinforced concrete piers designed based on ductility. Piers designed according to this concept can undergo plastic deformation under earthquakes to avoid brittle failure or even collapse. The ductility-based design concept allows plastic hinges to be generated at the bottom of the piers under earthquakes, dissipating earthquake energy through the deformation of the plastic hinges. The generation of plastic hinges can also reduce the stiffness of the piers, extend the basic period of the piers, and thus reduce earthquake damage. However, due to the plastic deformation of the plastic hinges, the residual displacement of reinforced concrete piers based on the ductility design concept is too large after the earthquake. Large residual displacement often makes repair difficult or even impossible, and requires demolition and reconstruction, which will consume a lot of time and money. Summary of the invention

[0004] In view of this, the object of the present invention is to provide a prefabricated pier connection node and construction method for a square single pile. When an earthquake occurs, the prestressed steel strands in the square pier can provide reset capability to reduce the residual displacement of the pier, and the energy-absorbing steel bars in the pier can dissipate the seismic energy.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] The present invention provides a prefabricated pier column connection node for a square single pile, comprising a pier column arranged in a square shape and a pile foundation fixedly connected to the pier column, the pier column being prefabricated by pouring high-toughness concrete, a plurality of frame bars being arranged in an array in the pier column, the plurality of frame bars being fixed by binding with stirrups arranged side by side along the axial direction of the pier column, a plurality of prestressed steel strands extending along the axial direction of the pier column being arranged in a middle array in the pier column, a plastic hinge area being arranged at the bottom of the pier column, energy-absorbing steel bars being arranged in the plastic hinge area of ​​the pier column, a pile foundation expansion section being arranged coaxially with the pile foundation on the pile foundation, the length of the pile foundation expansion section being greater than the length of the pile foundation, a steel sleeve being arranged on the outer surface of the pile foundation expansion section, a socket section being arranged on the pile foundation expansion section, after pouring concrete to form the pile foundation expansion section, the pier column is hoisted into the steel sleeve, and high-toughness concrete is poured into the steel sleeve to form the socket section connected to the pile foundation expansion section, so that the pier column is connected to the pile foundation.

[0007] Furthermore, the pier column extends to the outer wall of the socket section, and teeth keys surrounding the pier column are arranged side by side along the axial direction of the pier column.

[0008] Furthermore, at least two groups of energy-absorbing components are installed side by side in the steel sleeve along the axis direction of the pier, and each group of energy-absorbing components includes four U-shaped energy-absorbing plates arranged around the pier, the arc section of the U-shaped energy-absorbing plate is arranged close to the side wall of the pier, the two horizontal arms of the U-shaped energy-absorbing plate are arranged horizontally, a gap is arranged between the U-shaped energy-absorbing plate and the pier, and a gap is arranged between two adjacent U-shaped energy-absorbing plates arranged in the same vertical direction.

[0009] Furthermore, a plurality of elastic damping components are installed side by side between the two transverse arms of the U-shaped energy absorbing plate, and the elastic damping components include a sleeve, in which two pistons are slidably installed, a spring is fixedly connected between the two pistons, and a connecting rod is fixedly connected to the transverse arm side of the piston close to the U-shaped energy absorbing plate, and the connecting rod extends out of the sleeve and is fixedly connected to the transverse arm of the U-shaped energy absorbing plate.

[0010] Furthermore, an anchor connected to the energy-absorbing steel bar is provided at the bottom of the pier column. The anchor is arranged inside the pier column and is wrapped by high-toughness concrete.

[0011] Furthermore, a pile foundation steel cage and pile foundation main bars tied and fixed to the pile foundation steel cage are arranged in the pile foundation, a plurality of pile foundation main bars are arranged circumferentially with the pile foundation axis as the center, a plurality of expanded section steel bars are arranged circumferentially with the pile foundation expanded section axis as the center, the pile foundation main bars are arranged in the inner circle of the expanded section steel bars, and the pier column is arranged in the inner circle of the pile foundation main bars.

[0012] Furthermore, the pile foundation expansion section is connected with a ground tie beam, and the ground tie beam is provided with main reinforcement of the ground tie beam. The main reinforcement of the ground tie beam is inserted into the pile foundation expansion section and is located below the socket section. The steel sleeve is provided with reserved holes for the main reinforcement of the ground tie beam to pass through. After the main reinforcement of the ground tie beam is inserted into the reserved holes of the steel sleeve, concrete is poured into the steel sleeve to cover the main reinforcement of the ground tie beam to form the pile foundation expansion section, the pier is hoisted onto the pile foundation expansion section, and then high-toughness concrete is poured to form the socket section so that the pier and the pile foundation are connected as one.

[0013] A construction method for a prefabricated pier column connection node for a square monopile comprises the following steps:

[0014] S1: Precast piers by pouring high-toughness concrete;

[0015] S2: excavate a pile hole at the construction site, and place the steel sleeve, pile foundation steel cage, pile foundation expansion section steel cage and steel sleeve into the pile hole;

[0016] S3: Insert the main reinforcement of the ground tie beam from the reserved hole of the steel sleeve to the pile foundation expansion section, cast the pile foundation expansion section, pile foundation and ground tie beam, and realize the connection of the pile foundation expansion section, pile foundation and ground tie beam;

[0017] S4: After the pile foundation expansion section, pile foundation and ground tie beam reach the preset strength, fix the two sets of energy absorption components in the steel sleeve so that each U-shaped energy absorption plate is located between the inner wall of the steel sleeve and the outer wall of the pier column, and then hoist the pier column between the four U-shaped energy absorption plates;

[0018] S5: Pour high-toughness concrete in the steel sleeve to form a socket section that is integrated with the pile foundation expansion section, so that the pier column is connected to the pile foundation expansion section.

[0019] The beneficial effects of the present invention are:

[0020] In the present invention, when an earthquake occurs, the prestressed steel strands in the square pier column can provide a reset capability to reduce the residual displacement of the pier column, and the energy-absorbing steel bars in the pier column can dissipate the earthquake energy.

[0021] Other advantages, objectives and features of the present invention will be described in the following description and will be apparent to those skilled in the art to some extent, or those skilled in the art may be taught from the practice of the present invention. The objectives and other advantages of the present invention may be realized and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to make the purpose, technical solution and beneficial effects of the present invention clearer, the present invention provides the following drawings for illustration:

[0023] Figure 1 This is a schematic diagram of the overall structure of Embodiment 1 of the present invention;

[0024] Figure 2 This is a schematic diagram of the pier column structure according to the first embodiment of the present invention;

[0025] Figure 3 For the first embodiment of the present invention Figure 2 Schematic diagram of the cross section of the middle section aa;

[0026] Figure 4 For the first embodiment of the present invention Figure 2 Schematic diagram of the cross section of the middle section bb;

[0027] Figure 5 It is a schematic diagram of the connection between the pier column and the socket section, the pile foundation and the pile foundation expansion section according to the first embodiment of the present invention;

[0028] Figure 6 For the first embodiment of the present invention Figure 5 Schematic diagram of the cross section of the middle section cc;

[0029] Figure 7 It is a cross-sectional view of the socket section of the first embodiment of the present invention;

[0030] Figure 8 This is a schematic diagram of the connection between the ground tie beam and the pile foundation expansion section according to the first embodiment of the present invention;

[0031] Fig. 9 This is a schematic diagram of the installation of energy-consuming components in Embodiment 2 of the present invention.

[0032] The markings in the attached drawings are as follows: pier 1, prestressed steel strand 2, socket section 3, steel sleeve 4, expanded section steel bar 5, pile foundation 6, pile foundation main bar 7, ground beam 8, ground beam main bar 9, anchor 10, energy-absorbing steel bar 11, spiral stirrups 12, high-toughness concrete 13, pile foundation expanded section 14, tooth key 15, pile foundation steel bar cage 16, ground beam steel bar cage 17, expanded section steel bar cage 18, frame bar 19, U-shaped energy-absorbing plate 20, sleeve 21, piston 22, spring 23, connecting rod 24. DETAILED DESCRIPTION

[0033] Embodiment 1, as Figures 1 to 8 As shown, the present invention provides a prefabricated pier column connection node for a square single pile, comprising: a pier column 1 arranged in a square shape, and a pile foundation 6 fixedly connected to the pier column 1, wherein the pier column 1 is prefabricated by pouring high-toughness concrete 13, a plurality of frame bars 19 are arranged in an array in the pier column 1, and the plurality of frame bars 19 are tied and fixed with stirrups 12 arranged side by side along the axial direction of the pier column 1, a plurality of prestressed steel strands 2 extending axially along the pier column 1 are arranged in a middle array in the pier column 1, and the prestressed steel strands 2 are pre-tensioned bonded steel strands, a plastic hinge area is arranged at the bottom of the pier column 1, and an energy-absorbing steel bar 11 is arranged in the plastic hinge area of ​​the pier column 1, which can effectively dissipate seismic energy, and the An anchor 10 anchored to an energy-absorbing steel bar 11 is provided at the bottom of the pier 1. The anchor 10 is arranged inside the pier 1 and is wrapped by high-toughness concrete 13 to prevent the lower end of the prestressed steel strand 2 from bonding and slipping; the pile foundation 6 is provided with a pile foundation expansion section 14 coaxially arranged with the pile foundation 6, and the length of the pile foundation expansion section 14 is greater than the length of the pile foundation 6. A steel sleeve 4 is provided on the outer surface of the pile foundation expansion section 14, and a socket section 3 is provided on the pile foundation expansion section 14. After pouring concrete to form the pile foundation expansion section 14, the pier 1 is hoisted into the steel sleeve 4, and then high-toughness concrete is poured into the steel sleeve 4 to form the socket section 3 connected to the pile foundation expansion section 14, so that the pier 1 is connected to the pile foundation 6.

[0034] The pier 1 extends to the outer wall of the socket section 3, and tooth keys 15 surrounding the pier 1 are arranged side by side along the axial direction of the pier 1. After the pier 1 is inserted into the groove, high-toughness concrete is poured to provide connection strength between the socket section 3 and the pier 1.

[0035] The pile foundation 6 is provided with a pile foundation steel cage 16 and pile foundation main reinforcement 7 tied and fixed to the pile foundation steel cage 16. The pile foundation main reinforcement 7 is circumferentially arranged with the axis of the pile foundation 6 as the center. The pile foundation enlarged section 14 is provided with multiple enlarged section reinforcements 5 circumferentially arranged with the axis of the pile foundation enlarged section 14 as the center. The pile foundation main reinforcement 7 is arranged in the inner circle of the enlarged section reinforcement 5, and the pier 1 is arranged in the inner circle of the pile foundation main reinforcement 7.

[0036] The pile foundation expansion section 14 is connected to the ground tie beam 8, and the ground tie beam 8 is provided with the ground tie beam main reinforcement 9. The ground tie beam main reinforcement 9 is inserted into the pile foundation expansion section 14 and is located below the socket section 3. The steel sleeve 4 is provided with a reserved hole for the ground tie beam main reinforcement 9 to pass through. After the ground tie beam main reinforcement 9 is inserted into the reserved hole of the steel sleeve 4, concrete is poured into the steel sleeve 4 to cover the ground tie beam main reinforcement 9 to form the pile foundation expansion section 14, the pier 1 is hoisted onto the pile foundation expansion section 14, and then high-toughness concrete is poured to form the socket section 3 so that the pier 1 and the pile foundation 6 are connected as a whole.

[0037] The construction method of the first embodiment includes the following steps:

[0038] S1: Prefabricated pier 1 by pouring high-toughness concrete;

[0039] S2: excavating a pile hole at the construction site, placing the steel sleeve 4, the pile foundation steel cage 17, the pile foundation expansion section steel cage 18 and the steel sleeve 4 into the pile hole;

[0040] S3: insert the main reinforcement 9 of the ground tie beam from the reserved hole of the steel sleeve 4 to the pile foundation expansion section 14, cast the pile foundation expansion section 14, the pile foundation 6 and the ground tie beam 8, and realize the connection of the pile foundation expansion section 14, the pile foundation 6 and the ground tie beam 8;

[0041] S4: After the pile foundation expansion section 14, the pile foundation 6 and the ground tie beam 8 reach the preset strength, the pier column 1 is hoisted to the inner side of the pile foundation main reinforcement 7;

[0042] S5: pouring high-toughness concrete in the steel sleeve 4 to form the socket section 3 integrated with the pile foundation expansion section 14 , so that the pier 1 is connected to the pile foundation expansion section 14 .

[0043] Embodiment 2, as Fig. 9 Based on the first embodiment, at least two groups of energy absorbing components are installed side by side in the steel sleeve 4 along the axial direction of the pier 1, and each group of energy absorbing components includes four U-shaped energy absorbing plates 20 arranged around the pier 1, and the arc section of the U-shaped energy absorbing plate 20 is arranged close to the side wall of the pier 1, and a gap is provided between the U-shaped energy absorbing plate 20 and the pier 1 to ensure that the high-toughness concrete can wrap the U-shaped energy absorbing plate 20, and a gap is provided between two adjacent U-shaped energy absorbing plates 20 arranged in the same vertical direction to improve the connection strength of the U-shaped energy absorbing plate 20.

[0044] In this solution, the U-shaped energy absorption plate 20 is installed in the steel sleeve 4, and then the pier 1 is hoisted between the four U-shaped energy absorption plates 20, so that the side walls of the pier 1 are respectively arranged opposite to the arc sections of the four U-shaped energy absorption plates 20, and then high-toughness concrete is poured to cover the two groups of energy absorption components. When vibration occurs, the energy absorption effect can be further enhanced by the U-shaped energy absorption plate 20; and a gap is provided between two adjacent U-shaped energy absorption plates 20 arranged vertically to improve the connection strength between the U-shaped energy absorption plate 20 and the pier 1 after the high-toughness concrete is poured, and the U-shaped energy absorption plate 20 can play a vertical and tangential energy absorption role.

[0045] Furthermore, a plurality of elastic damping components are installed side by side between the two cross arms of the U-shaped energy absorbing plate 20, and the elastic damping components include a sleeve 21, in which two pistons 22 are slidably installed, and a spring 23 is fixedly connected between the two pistons 22. The piston 22 is fixedly connected to a connecting rod 24 on the cross arm side close to the U-shaped energy absorbing plate 20, and the connecting rod 24 extends out of the sleeve 21 and is fixedly connected to the cross arm of the U-shaped energy absorbing plate 20.

[0046] In this solution, the two cross arms of the U-shaped energy dissipation plate 20 are supported by an elastic damping component to reduce the deformation of the U-shaped energy dissipation plate 20 caused by the high-toughness concrete pouring process. When vibration occurs, the friction resistance between the piston 22 and the inner wall of the sleeve 21 and the elastic force of the spring 23 further dissipate energy and improve the reset ability of the U-shaped energy dissipation plate 20.

[0047] Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail through the above preferred embodiments, those skilled in the art should understand that various changes can be made in form and details without departing from the scope defined by the claims of the present invention.

Claims

1. A prefabricated pier column connection node for a square single pile, comprising pier columns arranged in a square shape and pile foundations fixedly connected to the pier columns, characterized in that: The pier is prefabricated by pouring high-toughness concrete, a plurality of frame bars are arranged in an array inside the pier, and the plurality of frame bars are tied and fixed to stirrups arranged side by side along the axial direction of the pier, a plurality of prestressed steel strands extending along the axial direction of the pier are arranged in a middle array inside the pier, a plastic hinge area is arranged at the bottom of the pier, and energy-absorbing steel bars are arranged in the plastic hinge area of ​​the pier, a pile foundation expansion section coaxially arranged with the pile foundation is provided on the pile foundation, the length of the pile foundation expansion section is greater than the length of the pile foundation, a steel sleeve is provided on the outer surface of the pile foundation expansion section, and a socket section is provided on the pile foundation expansion section. After pouring concrete to form the pile foundation expansion section, the pier is hoisted into the steel sleeve, and high-toughness concrete is poured into the steel sleeve to form a socket section connected to the pile foundation expansion section, so that the pier is connected to the pile foundation.

2. The prefabricated pier column connection node for square monopile according to claim 1, characterized in that: The pier column extends to the outer wall of the socket section, and teeth keys surrounding the pier column are arranged side by side along the axial direction of the pier column.

3. The prefabricated pier column connection node for square monopile according to claim 2, characterized in that: At least two groups of energy-absorbing components are installed side by side in the steel sleeve along the axis direction of the pier column, and each group of energy-absorbing components includes four U-shaped energy-absorbing plates arranged around the pier column, the arc section of the U-shaped energy-absorbing plate is arranged close to the side wall of the pier column, the two horizontal arms of the U-shaped energy-absorbing plate are arranged horizontally, a gap is arranged between the U-shaped energy-absorbing plate and the pier column, and a gap is arranged between two adjacent U-shaped energy-absorbing plates arranged in the same vertical direction.

4. The prefabricated pier column connection node for square monopile according to claim 3, characterized in that: A plurality of elastic damping components are installed side by side between the two cross arms of the U-shaped energy absorbing plate. The elastic damping components include a sleeve. Two pistons are slidably installed in the sleeve. A spring is fixedly connected between the two pistons. A connecting rod is fixedly connected to the cross arm side of the piston close to the U-shaped energy absorbing plate. The connecting rod extends out of the sleeve and is fixedly connected to the cross arm of the U-shaped energy absorbing plate.

5. The prefabricated pier column connection node for square monopile according to claim 4, characterized in that: An anchor connected to the energy-absorbing steel bar is provided at the bottom of the pier column. The anchor is arranged inside the pier column and is wrapped by high-toughness concrete.

6. The prefabricated pier column connection node for square monopile according to claim 5, characterized in that: The pile foundation is provided with a pile foundation steel cage and pile foundation main bars fixed to the pile foundation steel cage. The pile foundation main bars are arranged circumferentially with the pile foundation axis as the center. The pile foundation expansion section is provided with multiple expansion section steel bars circumferentially with the pile foundation expansion section axis as the center. The pile foundation main bars are arranged in the inner circle of the expansion section steel bars, and the pier is arranged in the inner circle of the pile foundation main bars.

7. The prefabricated pier column connection node for square monopile according to claim 6, characterized in that: The pile foundation expansion section is connected with a ground tie beam, and the ground tie beam is provided with main reinforcement of the ground tie beam. The main reinforcement of the ground tie beam is inserted into the pile foundation expansion section and is located below the socket section. The steel sleeve is provided with reserved holes for the main reinforcement of the ground tie beam to pass through. After the main reinforcement of the ground tie beam is inserted into the reserved holes of the steel sleeve, concrete is poured into the steel sleeve to cover the main reinforcement of the ground tie beam to form the pile foundation expansion section, the pier is hoisted onto the pile foundation expansion section, and then high-toughness concrete is poured to form the socket section so that the pier and the pile foundation are connected as one.

8. The construction method of the prefabricated pier column connection node for square monopile according to any one of claims 1 to 7, characterized in that: The following steps are involved: S1: Precast piers by pouring high-toughness concrete; S2: excavate a pile hole at the construction site, and place the steel sleeve, pile foundation steel cage, pile foundation expansion section steel cage and steel sleeve into the pile hole; S3: Insert the main reinforcement of the ground tie beam from the reserved hole of the steel sleeve to the pile foundation expansion section, cast the pile foundation expansion section, pile foundation and ground tie beam, and realize the connection of the pile foundation expansion section, pile foundation and ground tie beam; S4: After the pile foundation expansion section, pile foundation and ground tie beam reach the preset strength, fix the two sets of energy absorption components in the steel sleeve so that each U-shaped energy absorption plate is located between the inner wall of the steel sleeve and the outer wall of the pier column, and then hoist the pier column between the four U-shaped energy absorption plates; S5: Pour high-toughness concrete in the steel sleeve to form a socket section that is integrated with the pile foundation expansion section, so that the pier column is connected to the pile foundation expansion section.

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