A prestressed beam-column joint structure and its construction method

Abstract

The present invention provides a prestressed beam-column joint structure and a construction method thereof. The prestressed beam-column joint structure includes a formwork border, a pipe liner, a pre-embedded corrugated pipe for column prestressed tendons, a pre-embedded corrugated pipe for beam prestressed tendons, a post-tensioned prestressed steel tendon bundle, a steel fiber-reinforced high-strength joint filling bonding material, a steel fiber-reinforced high-strength seat grout, and a high-strength joint filling bonding material. The present invention has low requirements for the extended length of the corrugated pipe of the beam-column joint structure, and the materials used in each construction step are easily available. Even if the corrugated pipe is damaged, it does not affect the construction quality, and prefabrication and transportation are more convenient. The two-time joint filling process above and below the corrugated pipe is adopted to avoid the problem that the joint of the beam-column corrugated pipe is not tightly sealed in the one-time joint filling process, and the grouting material enters the corrugated pipe and affects the subsequent duct grouting. Since there is no sealing tape for sealing, the process of using the sealing tape for sealing is omitted, improving the construction efficiency. In addition, since there is no need to customize the shaped sealing ring material, the cost is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of pre-stressed precast concrete building construction, and particularly relates to a pre-stressed beam-column joint structure and a construction method thereof. Background Technique

[0002] At present, there are mainly two construction methods for pre-stressed beam-column joints. One is the patent "A precast beam-column joint structure with pre-stressed ducts and its construction method CN201710113805.0", and the other is the patent "A precast beam-column joint structure with socketed corrugated pipes and its construction method CN201910476216.8". The main method is to seal between the beam-column corrugated pipes with a sealing tape or a shaped sealing ring material, and then pour grout into the beam-column joint. However, the above methods have the following disadvantages:

[0003] 1. The construction space for the sealing tape is small, the operation of winding the sealing tape on site is inconvenient, the construction efficiency is low, and the quality requirements for the production of precast components are high, which is difficult to guarantee in actual projects.

[0004] 2. The shaped sealing ring material needs to be customized, the material is not easily obtained, the cost is high, and the quality is not easily controlled in actual operation.

[0005] In view of the above problems, a construction method for beam-column joints with easily available materials and rapid construction needs to be proposed. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a pre-stressed beam-column joint structure and a construction method thereof, aiming at the problems of difficult construction quality assurance, slow construction speed, difficult material acquisition and high cost existing in the existing construction methods of pre-stressed beam-column joints.

[0007] The present invention is implemented as follows. A prestressed beam-column joint structure includes a formwork border, a pipe lining, a pre-embedded corrugated pipe for column prestressed tendons, a pre-embedded corrugated pipe for beam prestressed tendons, a post-tensioned prestressed steel tendon bundle, a steel fiber-reinforced high-strength joint grouting adhesive material, a steel fiber-reinforced high-strength seat grout, and a high-strength joint grouting adhesive material. The formwork border seals the bottom and both side surfaces of the joint between the beam section and the column. The pre-embedded corrugated pipe for column prestressed tendons is pre-embedded in the column, and the pre-embedded corrugated pipe for beam prestressed tendons is pre-embedded in the beam. The ports of the pre-embedded corrugated pipe for column prestressed tendons and the pre-embedded corrugated pipe for beam prestressed tendons are aligned with each other at the joint position. The post-tensioned prestressed steel tendon bundle sequentially passes through the pre-embedded corrugated pipe for beam prestressed tendons and the pre-embedded corrugated pipe for column prestressed tendons. The pipe lining is embedded in the formwork border. The pipe lining is composed of a hollow pipe. The bottom of the pipe lining has a horizontal pipe, which divides the formwork border into an upper cavity and a lower cavity that are isolated from each other. The end of the pre-embedded corrugated pipe for column prestressed tendons near the joint is located in the lower cavity, and the upper cavity is filled with the steel fiber-reinforced high-strength seat grout. The space from the bottom of the lower cavity to the center position of the pre-embedded corrugated pipe for beam prestressed tendons is filled with the steel fiber-reinforced high-strength joint grouting adhesive material. The space from the center position of the pre-embedded corrugated pipe for beam prestressed tendons to the bottom of the lower cavity is filled with the high-strength joint grouting adhesive material. The horizontal pipe at the bottom of the pipe lining is provided with a grout inlet hole, and the top of the pipe lining is provided with a grout outlet hole. The top of the pipe lining extends upward out of the steel fiber-reinforced high-strength seat grout filled in the upper cavity, and the inside of the pipe of the pipe lining is filled with the high-strength joint grouting adhesive material.

[0008] Further, the formwork border is a fixed formwork or a high-strength seat grout formwork.

[0009] Further, the cross-section of the pipe lining in the longitudinal direction is in the shape of two L shapes, an inverted T shape, or a U shape that are back-to-back arranged.

[0010] Further, the material of the pipe lining is PVC or steel, and the diameter of the pipe of the pipe lining is 3 mm to 10 mm smaller than the width of the joint.

[0011] Further, the horizontal pipe at the bottom of the pipe lining is provided with two symmetrically distributed grout inlet holes, which are located 10 mm to 50 mm on both sides of the pre-embedded corrugated pipe for column prestressed tendons, and the opening direction is downward.

[0012] Further, the prestressed beam-column joint structure further includes bending-resistant steel bars and a post-cast layer of the beam. One end of the bending-resistant steel bars is connected to a steel bar connector pre-embedded in the column, and the other end is embedded in the post-cast layer of the beam. The post-cast layer of the beam covers the beam.

[0013] To solve the above technical problems, the present invention also provides a construction method for the above prestressed beam-column joint structure, which includes the following steps:

[0014] S1. The beam and column are positioned, and post-tensioned prestressed steel bundles are inserted into the embedded corrugated pipes for beam prestressed tendons and column prestressed tendons.

[0015] S2. The bottom surface and both side surfaces of the joint between the beam section and the column are sealed with a formwork border.

[0016] S3. Grout the joint between the beam section and the column using a high-strength grouting adhesive material with steel fibers. The grouting height is controlled between the bottom surface and the center position of the embedded corrugated pipe for column prestressed tendons, ensuring that the high-strength grouting adhesive material with steel fibers does not enter or only slightly enters the embedded corrugated pipes for column prestressed tendons and beam prestressed tendons.

[0017] S4. Place a pipe liner in the joint between the beam section and the column. Among them, the horizontal pipe at the bottom of the pipe liner is placed at the top surface position of the embedded corrugated pipe for column prestressed tendons.

[0018] S5. Compact the joint above the horizontal pipe of the pipe liner with a high-strength mortar with steel fibers.

[0019] S6. After the strength of the high-strength mortar with steel fibers reaches a predetermined value or above, carry out prestress tensioning. After the tensioning is completed, grout the embedded corrugated pipes for column prestressed tendons and beam prestressed tendons, inject a high-strength grouting adhesive material. After filling the embedded corrugated pipes for column prestressed tendons and beam prestressed tendons, the high-strength grouting adhesive material enters through the grouting holes at the bottom of the liner pipe and then exits through the bleeding holes. After all bleeding holes have bled, the entire construction process is completed.

[0020] Further, the high-strength mortar with steel fibers in step S5 is replaced with a high-strength grouting material with steel fibers having a fluidity of 150 mm - 250 mm.

[0021] Further, the high-strength grouting adhesive material injected in the above steps is one or a combination of two or more of a high-strength rapid-hardening cement-based grouting material with a compressive strength of more than 45 MPa, a fiber rapid-hardening cement-based grouting material, or a polymer mortar.

[0022] Further, the above construction method further includes the following steps:

[0023] Connect one end of a flexural steel bar to a steel bar connector embedded in the column, and pour a layer of post-cast layer on the top surface of the beam to cover the flexural steel bar.

[0024] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0025] The present invention provides a prestressed beam-column joint structure and its construction method, which have low requirements for the extended length of the corrugated pipe in the beam-column joint structure, and the materials used in each construction step are easily obtained. Even if the corrugated pipe is damaged, it does not affect the construction quality, and prefabrication and transportation are more convenient. The construction method adopts a two-time grouting process above and below the corrugated pipe, avoiding the problem that the joint of the beam-column corrugated pipe is not tightly sealed in the one-time grouting process, and the grouting material enters the corrugated pipe, affecting the subsequent duct grouting. Since there is no sealing tape for sealing, the process of using the sealing tape for sealing in the original construction method is omitted, improving the construction efficiency. In addition, since there is no need to customize and shape the sealing ring material, the cost is reduced. Description of the Drawings

[0026] Figure 1 is a front view schematic diagram of a prestressed beam-column joint structure provided by an embodiment of the present invention;

[0027] Figure 2 is Figure 1 a sectional view schematic diagram of the prestressed beam-column joint structure shown along the A-A section line;

[0028] Figure 3 is a sectional view schematic diagram of a prestressed beam-column joint structure with a U-shaped pipe liner provided by an embodiment of the present invention;

[0029] Figure 4 is a sectional view schematic diagram of a prestressed beam-column joint structure with an inverted T-shaped pipe liner provided by an embodiment of the present invention;

[0030] Figure 5 is a front view schematic diagram of a prestressed beam-column joint structure with a middle node provided by an embodiment of the present invention;

[0031] Figures 6a to 6f is a schematic diagram of each state during the construction process of a prestressed beam-column joint structure provided by an embodiment of the present invention.

[0032] Description of the Reference Numerals:

[0033] 1 - Formwork border; 2 - Pipe liner; 21 - Horizontal pipe; 211 - Grout inlet hole; 22 - Grout outlet hole; 3 - Column prestressed tendon embedded corrugated pipe; 4 - Beam prestressed tendon embedded corrugated pipe; 5 - Post-tensioned prestressed steel tendon bundle; 6 - Prestressed tendon external anchor head; 7 - Steel fiber reinforced high-strength grouting bonding material; 8 - Steel fiber reinforced high-strength seat grouting material; 9 - High-strength grouting bonding material; 10 - Bending-resistant steel bar; 11 - Beam post-cast layer; 100 - Column; 101 - Steel bar connector; 200 - Beam. Detailed Embodiments

[0034] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0035] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, so it should not be understood as a limitation of the present invention; the terms "first", "second", "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance; in addition, unless otherwise clearly specified and limited, the terms "installation", "connection", "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0036] Please refer to Figure 1 and Figure 2 , which shows a prestressed beam-column joint structure provided by the present invention, which includes a formwork edge 1, a pipe liner 2, a column prestressed tendon embedded corrugated pipe 3, a beam prestressed tendon embedded corrugated pipe 4, a post-tensioned prestressed steel tendon bundle 5, a prestressed tendon external anchor head 6, a steel fiber reinforced high-strength joint bonding material 7, a steel fiber reinforced high-strength seat mortar 8, and a high-strength joint bonding material 9.

[0037] The formwork edge 1 seals the bottom and both side surfaces of the joint between the beam section and the column. The formwork edge 1 is a fixed formwork or a high-strength seat mortar formwork. The column prestressed tendon embedded corrugated pipe 3 is embedded in the column 100, and the beam prestressed tendon embedded corrugated pipe 4 is embedded in the beam 200. The ports of the column prestressed tendon embedded corrugated pipe 3 and the beam prestressed tendon embedded corrugated pipe 4 at the joint position between the beam and the column are aligned with each other. The post-tensioned prestressed steel tendon bundle 5 passes through the beam prestressed tendon embedded corrugated pipe 4 and the column prestressed tendon embedded corrugated pipe 3 in sequence, and the beam 200 and the column 100 are tensioned and fastened through the prestressed tendon external anchor head 5.

[0038] The pipe liner 2 is embedded in the bulkhead frame 1. The pipe liner 2 is composed of a hollow pipe. The bottom of the pipe liner 2 has a horizontal pipe 21, and the horizontal pipe 21 divides the bulkhead frame into an upper cavity and a lower cavity that are isolated from each other. The end of the column prestressed tendon embedded corrugated pipe 3 near the joint is located in the lower cavity, and the upper cavity is filled with high-strength seat grout 8 mixed with steel fibers; the space from the bottom of the lower cavity to the center position of the beam prestressed tendon embedded corrugated pipe 4 is filled with high-strength grouting and bonding material 7 mixed with steel fibers.

[0039] The space from the center position of the beam prestressed tendon embedded corrugated pipe 4 to the bottom of the lower cavity is filled with high-strength grouting and bonding material 9. The horizontal pipe 21 at the bottom of the pipe liner 2 is provided with two symmetrically distributed grouting holes 211. The grouting holes 211 are located 10 mm to 50 mm on both sides of the column prestressed tendon embedded corrugated pipe 3, and the opening direction is downward. The top of the pipe liner 2 is provided with a grouting hole 22. The top of the pipe liner 2 extends upward into the high-strength seat grout 8 mixed with steel fibers filled in the upper cavity, and the inside of the pipe of the pipe liner 2 is filled with high-strength grouting and bonding material 9.

[0040] In this embodiment, the high-strength seat grout 8 mixed with steel fibers filled in the upper cavity is replaced by high-strength grouting material mixed with steel fibers. The material of the pipe liner 2 is PVC or steel, and the diameter of the pipe of the pipe liner 2 is 3 mm to 10 mm smaller than the width of the joint. The cross-section of the pipe liner 2 in the longitudinal direction is two L-shapes arranged back to back. In practical applications, please refer to Figure 3 and Figure 4 , the pipe liner 2 can also be U-shaped or inverted T-shaped.

[0041] Optionally, the above prestressed beam-column joint structure further includes bending-resistant steel bars 10 and a post-cast layer 11 of the beam. One end of the bending-resistant steel bar 10 is connected to the steel bar connector 101 embedded in the column 100, and the other end is embedded in the post-cast layer 11 of the beam, covering the post-cast layer 11 on the beam 200.

[0042] Please refer to Figure 5 , a prestressed beam-column joint structure with a middle joint provided in this embodiment. The prestressed beam-column joint structure can omit the external anchor head 6 of the prestressed tendon. The post-tensioned prestressed steel tendon bundle 5 on one side of the beam-column joint structure is prestressed and tightened by means of the beam-column joint structure on the other side.

[0043] Please refer to Figures 6a to 6f , the construction steps of the prestressed beam-column joint structure in this embodiment are as follows:

[0044] S1. The beam 200 and the column 100 are in place, and the post-tensioned prestressed steel tendon bundle 5 is inserted into the beam prestressed tendon embedded corrugated pipe 4 and the column prestressed tendon embedded corrugated pipe 3;

[0045] S2. Use the bulkhead frame 1 to seal the bottom surface and both side surfaces of the joint between the beam section and the column;

[0046] S3, use the steel fiber-doped high-strength joint-filling adhesive material 7 to grout the joints at the contact between the beam section and the column, and control the grouting height between the bottom surface and the center position of the column prestressed tendon pre-embedded corrugated pipe 3 to ensure that the steel fiber-doped high-strength joint-filling adhesive material 7 does not enter or enters a small amount of the column prestressed tendon pre-embedded corrugated pipe 3 and the beam prestressed tendon pre-embedded corrugated pipe 4;

[0047] S4, placing the pipe liner 2 in the joint between the beam section and the column, wherein the horizontal pipe 21 at the bottom of the pipe liner 2 is placed at the top surface of the prestressed tendon pre-embedded corrugated pipe 3 of the column;

[0048] S5, using the steel fiber-added high-strength seat slurry 8 to press and plug the joints above the horizontal pipe 21 of the pipe liner 2;

[0049] S6, after the strength of the steel fiber-doped high-strength seat slurry 8 reaches more than 30Mpa, prestressing is performed. After the prestressing is completed, grouting is performed on the column prestressed tendon pre-embedded corrugated pipe 3 and the beam prestressed tendon pre-embedded corrugated pipe 4, and high-strength grouting adhesive material 9 is injected. After the column prestressed tendon pre-embedded corrugated pipe 3 and the beam prestressed tendon pre-embedded corrugated pipe 4 are filled, the high-strength grouting adhesive material 9 enters from the grout inlet hole 211 at the bottom of the liner 2, and then slurries out from the slurry outlet hole 22. After all the slurry outlet holes 22 are slurried, the grouting operation is completed;

[0050] S7, connect one end of the bending steel bar 10 to the pre-buried steel bar connector 101 in the column 100, pour a beam post-cast layer 11 on the top surface of the beam 200, make the beam post-cast layer 12 cover the bending steel bar 10, and complete the entire construction process.

[0051] Furthermore, the steel fiber-added high-strength seat slurry 8 in step S5 is replaced with a steel fiber-added high-strength grouting material with a fluidity of 150 mm to 250 mm. The high-strength grouting adhesive material 9 injected in the above step is one or a combination of two or more of a high-strength fast-hardening cement-based grouting material with a compressive strength of more than 45 MPa, a fiber fast-hardening cement-based grouting material or a polymer mortar.

[0052] The beam-column joint structure and its construction method of this embodiment do not require high extension length of the corrugated pipe of the beam-column joint structure, and the materials used in each construction step are easy to obtain. Even if the corrugated pipe is damaged, it will not affect the construction quality, and prefabrication and transportation are more convenient. The construction method adopts two grouting processes, the upper and lower bellows, to avoid the problem of poor sealing at the joint of the beam-column corrugated pipe in the one-time grouting process, and the grouting material enters the bellows and affects the grouting of the later channel. Since there is no sealing tape, the process of sealing with sealing tape in the original construction method is omitted, which improves the construction efficiency. In addition, since no customized sealing ring materials are required, the cost is reduced.

[0053] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A prestressed beam-column joint structure, characterized in that, It includes a sealed bin frame, a pipe lining, a corrugated pipe for pre-embedded column prestressed tendons, a corrugated pipe for pre-embedded beam prestressed tendons, post-tensioned prestressed steel tendon bundles, a high-strength grouting bonding material with steel fibers, a high-strength seat mortar with steel fibers, and a high-strength grouting bonding material; the sealed bin frame seals the bottom and two side surfaces of the joint between the beam section and the column; the corrugated pipe for pre-embedded column prestressed tendons is pre-embedded in the column, and the corrugated pipe for pre-embedded beam prestressed tendons is pre-embedded in the beam. The ports of the corrugated pipe for pre-embedded column prestressed tendons and the corrugated pipe for pre-embedded beam prestressed tendons are aligned with each other at the joint position. The post-tensioned prestressed steel tendon bundles sequentially pass through the corrugated pipe for pre-embedded beam prestressed tendons and the corrugated pipe for pre-embedded column prestressed tendons; the pipe lining is embedded in the sealed bin frame. The pipe lining is composed of a hollow pipe. The bottom of the pipe lining has a horizontal pipe, and the horizontal pipe divides the sealed bin frame into an upper cavity and a lower cavity that are isolated from each other up and down. The end of the corrugated pipe for pre-embedded column prestressed tendons close to the joint is located in the lower cavity, and the upper cavity is filled with the high-strength seat mortar with steel fibers; the space from the bottom of the lower cavity to the center position of the corrugated pipe for pre-embedded beam prestressed tendons is filled with a high-strength grouting bonding material with steel fibers; the space from the center position of the corrugated pipe for pre-embedded beam prestressed tendons to the bottom of the upper cavity is filled with a high-strength grouting bonding material. The horizontal pipe at the bottom of the pipe lining is provided with a grouting hole, and the top of the pipe lining is provided with a bleeding hole; the top of the pipe lining extends upward out of the high-strength seat mortar filled in the upper cavity, and the inside of the pipe of the pipe lining is filled with a high-strength grouting bonding material; the sealed bin frame is a fixed formwork or a sealed bin with high-strength seat mortar; the cross-section of the pipe lining in the longitudinal direction is in the shape of two Ls back to back, an inverted T shape, or a U shape.

2. The prestressed beam-column joint structure according to claim 1, wherein, The material of the pipe lining is PVC or steel, and the diameter of the pipe of the pipe lining is 3 mm to 10 mm smaller than the width of the joint.

3. The prestressed beam-column joint structure according to claim 1, characterized in that, The horizontal pipe at the bottom of the pipe lining is provided with two symmetrically distributed grouting holes. The grouting holes are located 10 mm to 50 mm on both sides of the corrugated pipe for pre-embedded column prestressed tendons, and the opening direction is downward.

4. The prestressed beam-column joint structure according to claim 1, characterized in that, The prestressed beam-column joint structure further includes flexural reinforcement and a post-cast layer of the beam. One end of the flexural reinforcement is connected to a steel bar connector pre-embedded in the column, and the other end is embedded in the post-cast layer of the beam. The post-cast layer of the beam covers the beam.

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