Method for connecting concrete column and steel pipe concrete column

Abstract

The invention discloses a method for connecting a concrete column and a concrete-filled steel tubular column, and relates to the technical field of steel-concrete composite structures, the connecting method comprises the following specific steps: S100, mounting and treating an inner partition plate: the height of a steel column exceeds 1 / 3 of the clear height of a floor, the inner partition plate is mounted at a floor slab at the position, and a grouting hole with the diameter of 20-50mm is formed in the middle of the inner partition plate; the surface of the inner partition plate is subjected to special roughening treatment, the friction force between the inner partition plate and the steel column and the friction force between the inner partition plate and the grouting material are remarkably enhanced, and therefore the shear resistance of the connecting joint is improved, the roughening treatment not only optimizes the adhesion and meshing effects of the grouting material, but also ensures that the grouting material can be more evenly distributed in the connecting joint, and the connecting joint is more stable. In addition, due to the application of the novel welding seam reinforcing agent, the strength and toughness of the welding seam are remarkably improved, the rusting problem of the welding seam in a humid environment is effectively prevented, and therefore the service life of the connecting structure is prolonged.

Description

Technical Field

[0001] The invention relates to the technical field of steel-concrete composite structures, in particular to a method for connecting a concrete column and a steel tube concrete column. Background Art

[0002] In the field of building structures, the combination of steel columns and concrete columns is widely used in various construction projects. With the continuous development of building design and construction technology, the connection technology requirements between different structural forms are increasing. The performance of the connection nodes between steel columns and concrete columns directly affects the safety, integrity and durability of the entire structure. In modern buildings, especially high-rise buildings, large-span buildings and industrial buildings, it is often necessary to use a combination of steel columns and concrete columns on different floors or structural parts to give full play to the advantages of the two materials and meet the needs of building structures in terms of bearing capacity, spatial layout and economy.

[0003] In traditional technology, the method of connecting concrete columns to steel columns is relatively mature, and the connection is often achieved by pre-embedded anchor bolts and pre-embedded steel parts. However, there is a lack of effective solutions for the connection between steel columns and concrete columns. The existing conventional connection technology is difficult to directly apply to the situation where steel columns are connected to concrete columns. As a result, when facing such structural requirements, engineers and construction personnel often face many difficulties. For example, in the design of the connection node, it is impossible to ensure the effective transmission of force between the steel column and the concrete column, and stress concentration is prone to occur, which reduces the bearing capacity and structural stability of the connection node. During the construction process, due to the lack of targeted processes and technical measures, it is difficult to ensure the accurate installation and connection quality of each component. For example, the connection reliability of the steel bar connector and the vertical main reinforcement and the filling density of the grouting material are difficult to effectively solve, which in turn affects the performance and service life of the entire structure.

[0004] Therefore, the development of a method for connecting concrete columns and concrete-filled steel tube columns provides a new technical means for building structure design and construction, filling the gap in the reverse connection technology between steel columns and concrete columns. Summary of the invention

[0005] The purpose of the present invention is to make up for the deficiencies of the prior art and to provide a method for connecting a concrete column and a steel tube concrete column. The method includes the steps of installing and processing an inner partition, welding and processing a steel bar connector, connecting a vertical main reinforcement, installing and welding an end cover plate, and grouting. The strength and stability of the connection node are ensured by precisely controlling welding parameters and processes. The inner partition is made of high-strength low-alloy structural steel and is roughened to improve the connection quality. The steel bar connector is made of high-strength alloy steel and is subjected to a heat treatment process to ensure welding strength and durability. The vertical main reinforcement connection is made of manual arc welding, and the weld quality and interlayer temperature are controlled by multi-layer and multi-pass welding. The end cover plate is pre-deformed according to structural mechanics analysis and simulation calculations to ensure flatness and tightness after welding. The grouting operation adopts a step-by-step vibration grouting process to ensure the uniformity and density of the grouting material.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions: a method for connecting a concrete column and a steel tube concrete column, wherein the specific steps of the connection method are: S100, installation and treatment of inner partition: The height of the steel column exceeds 1 / 3 of the net height of the floor, and the inner partition is installed on the floor slab at this position. A grouting hole with a diameter of 20-50 mm is opened in the middle of the inner partition; S200, welding and treatment of steel bar connectors: according to the requirements for positioning the vertical main reinforcement of the concrete column, measure and mark the welding position of the steel bar connector on the installed inner partition, and control the error within ±2mm. Apply weld reinforcement agent at the welding point between the steel bar connector and the inner partition, with a thickness of 0.5-1.5mm. The steel bar connector is welded by carbon dioxide gas shielded welding, with a welding current of 180-220A, a voltage of 22-26V, and a welding speed of 30-50cm / min. After welding, perform appearance and ultrasonic flaw detection; S300, vertical main reinforcement connection: connect the bottom of the vertical main reinforcement of the concrete column with the welded steel bar connector, and use manual arc welding for the side of the vertical main reinforcement and the vertical main reinforcement positioning plate. The welding current is 150-180A, the voltage is 20-24V, the welding rod is E4303, and the welding length is 10d, where d is the diameter of the vertical main reinforcement; S400, installation and welding of end sealing plates: according to the size and shape of the steel column head, the end sealing plates are processed and manufactured. Before welding the end sealing plates on the steel column head, the reverse deformation amount and direction are determined according to structural mechanics analysis and simulation calculation. A special hydraulic jack is used to perform reverse deformation on the end sealing plates. The deformation process is monitored by a total station. The pre-deformed end sealing plates are placed at the predetermined position of the steel column head. Manual arc welding is used from the center to the surroundings. The welding current is 160-190A, the voltage is 21-25V, and the welding rod is E5015 type. The welding speed is controlled to be 25-35cm / min. After welding, the welding tightness and flatness are checked, and the flatness deviation is controlled within ±1mm; S500, grouting operation: after completing the end sealing plate welding, grouting operation is carried out through the grouting hole. The grouting operation adopts a step-by-step vibration grouting process. According to the requirements of the grouting material mix ratio, the cement, aggregate, and admixture raw materials are weighed, and the mixed grouting material is grouted through the grouting equipment. The first grouting volume is controlled between 1 / 3-1 / 2 of the volume of the connection node, and a small high-frequency vibrator is used to briefly vibrate the connection node. The vibration frequency is set between 100-150 Hz and the vibration time is 10-20 seconds. After the vibration is completed, the grouting operation is repeated until the grouting material is close to the top of the grouting hole, 50-100mm away from the top of the hole, and the vibrator is used to vibrate again. After the grouting is completed, the connection node is maintained.

[0007] Furthermore, in the S100, the material of the inner partition during the installation and processing of the inner partition is high-strength low-alloy structural steel, with a yield strength of not less than 345MPa and a tensile strength of not less than 470MPa. Before the installation of the inner partition, the surface of the inner partition is subjected to a special roughening treatment, and the inner partition is placed on a dedicated processing platform. A spray gun is used to evenly spray hard particles with a particle size of 10-100 microns at a pressure of 0.4-0.6MPa at a distance of 20-30 cm from the surface of the inner partition.

[0008] Furthermore, in the S100, the inner partition plate installed and processed in the processing is installed at a predetermined position of the steel column and initially fixed by intermittent welding, with a weld length of 30-50 mm and a spacing of 100-150 mm.

[0009] Furthermore, the weld reinforcement agent in the welding and processing of the steel bar connector in S200 is based on epoxy resin, which accounts for 30%-40% by mass; 20%-30% of curing agent is added; it contains 10%-15% iron powder; 5%-10% rare earth elements; and 10%-20% solvent.

[0010] Furthermore, in the S200, the steel bar connector is welded and processed by using a high-strength alloy steel material, the yield strength of which is not less than 400 MPa, and the tensile strength of which is not less than 550 MPa.

[0011] Furthermore, in the S200, in the welding and processing of the steel bar connector, after the welding of the steel bar connector is completed, the weld is hammered, the hammering force is 1-3kN, the hammering frequency is 2-3 times / second, and the number of hammering times is 2-3 times.

[0012] Furthermore, in the S300, the vertical main reinforcement positioning plate in the vertical main reinforcement connection is made of Q345B steel plate with a thickness of 8-12mm, and the main reinforcement positioning groove on the positioning plate is processed by CNC technology, and the dimensional accuracy of the positioning groove is controlled within ±0.5mm.

[0013] Furthermore, in the S300, when the vertical main reinforcement is connected and the vertical main reinforcement positioning plate is welded, welding is performed in a multi-layer and multi-pass manner, the thickness of each layer of weld does not exceed 4 mm, the width of each weld does not exceed 10 mm, and the interlayer temperature is controlled not to exceed 200°C during the welding process.

[0014] Furthermore, in the S400, the end sealing plate is made of a stainless steel plate with a thickness of 12-18 mm during installation and welding, a grouting hole with a diameter of 20-50 mm and a 100-200 mm square operating hole are opened in the middle of the sealing plate, and reinforcement holes are accurately set around the sealing plate according to the position of the vertical main reinforcement, and the hole diameter is 2-5 mm larger than the diameter of the main reinforcement.

[0015] Furthermore, in the S400, the welding pre-deformation of the end cover plate is calculated during the installation and welding of the end cover plate, and the finite element analysis software ANSYS is used to simulate the subsequent actual stress condition of the connection node between the steel column and the concrete column, and analyze the deformation trend and deformation amount of the position of the end cover plate when the node is subjected to various expected loads.

[0016] Compared with the prior art, the method for connecting a concrete column with a steel tube concrete column has the following beneficial effects: 1. The present invention significantly enhances the friction between the inner partition and the steel column and the grouting material by performing a special roughening treatment on the surface of the inner partition, thereby improving the shear resistance of the connection node. This roughening treatment not only optimizes the adhesion and bite effect of the grouting material, but also ensures that the grouting material can be more evenly distributed in the connection node, further improving the overall stability and durability of the structure. In addition, the application of the new weld reinforcement agent significantly improves the strength and toughness of the weld, effectively preventing the weld from rusting in a humid environment, thereby extending the service life of the connection structure.

[0017] 2. The present invention further improves the performance of the connection structure through the step-by-step vibration grouting process and the pre-deformation welding process of the end sealing plate. The step-by-step vibration grouting process ensures that the grouting material can be more fully filled into each tiny gap of the connection node, expelling internal air, thereby improving the density of the grouting and the strength of the connection node, while the pre-deformation welding process of the end sealing plate effectively avoids the dimensional deviation and shape instability problems caused by thermal deformation during the welding process, ensures the tightness and flatness of the welding, and thus improves the overall stability and bearing capacity of the connection node.

[0018] Other advantages, objectives and features of the present invention will be set forth in part in the following description and, in part, will be apparent to those skilled in the art based on an examination of the following or may be taught from the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0020] Figure 1 A flow chart of a method for connecting a concrete column and a concrete-filled steel tube column; Figure 2 This is a three-dimensional model diagram of the connection node between the steel column and the concrete column; Figure 3 This is the internal cross-section diagram of the connection node between the steel column and the concrete column. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Example

[0022] Connection between concrete columns and steel columns in a high-rise office building Project background and connection node design: The building structure construction of a high-rise office building involves many connection nodes between concrete columns and steel columns. The connection nodes are located on standard floors. The cross-sectional dimensions of the concrete columns are 600mm×600mm, and the steel columns are H-shaped steel columns with cross-sectional specifications of H500×200×10×16. According to the design requirements, the steel columns need to be reliably connected to the concrete columns at the floors to transfer vertical and horizontal loads.

[0023] Connection method steps: S100, installation and treatment of inner partitions. The material of the inner partitions is high-strength low-alloy structural steel with a yield strength of 345MPa and a tensile strength of 470MPa. Before installation, the surface of the inner partitions is roughened and placed on a special processing platform. A spray gun is used to evenly spray hard particles with a particle size of 50 microns at a pressure of 0.5MPa at a distance of 25 cm from the surface of the inner partition. The treated inner partitions are installed at the predetermined position of the steel column and initially fixed by intermittent welding. The weld length is 40mm and the spacing is 120mm. A grouting hole with a diameter of 30mm is opened in the middle of the inner partition.

[0024] S200, welding and processing of steel bar connectors. The steel bar connectors are made of high-strength alloy steel with a yield strength of not less than 400MPa and a tensile strength of not less than 550MPa, and are subjected to a heat treatment process. According to the positioning requirements of the vertical main reinforcement of the concrete column, the welding position of the steel bar connector is measured and marked on the installed inner partition, and the error is controlled within ±2mm. The weld reinforcement agent is based on epoxy resin (35% by mass), with 25% curing agent, 12% iron powder, 8% rare earth elements and 15% solvent added. The welding process adopts carbon dioxide gas shielded welding, the welding current is 200A, the voltage is 24V, and the welding speed is 40cm / min. After welding, appearance and ultrasonic flaw detection are carried out. After passing the inspection, the weld is hammered with a hammer force of 2kN, a hammer frequency of 2.5 times / second, and a hammering number of 3 times.

[0025] S300, vertical main reinforcement connection, the diameter of the vertical main reinforcement of the concrete column is 25mm, and its bottom is connected to the welded steel bar connector. The side of the vertical main reinforcement and the vertical main reinforcement positioning plate are welded by manual arc welding. The welding current is 160A, the voltage is 22V, the welding rod is E4303, the welding length is 250mm, and the vertical main reinforcement positioning plate is made of Q345B steel plate with a thickness of 10mm. The main reinforcement positioning groove on the positioning plate is made of CNC processing technology, and the size accuracy of the positioning groove is controlled within ±0.5mm. The welding is carried out in multiple layers and multiple passes. The thickness of each layer of weld does not exceed 4mm, and the width of each weld does not exceed 10mm. The interlayer temperature is controlled not to exceed 200℃ during welding.

[0026] S400, installation and welding of end sealing plates. The end sealing plates are made of 15mm thick stainless steel plates. A grouting hole with a diameter of 30mm and a 150mm square operating hole are opened in the middle of the sealing plates. Reinforcement holes are accurately set around the sealing plates according to the positions of the vertical main reinforcements. The hole diameter is 3mm larger than the diameter of the main reinforcement. According to the principles of structural mechanics and ANSYS software, the subsequent actual stress state of the connection node between the steel column and the concrete column is simulated and calculated. It is determined that the reverse deformation amount that the end sealing plate needs to generate in advance is 2mm, and the deformation direction is upward. A special hydraulic jack is used to perform reverse deformation on the end sealing plate. The deformation process is monitored by a total station. The pre-deformed end sealing plate is placed at the predetermined position of the steel column head. Manual arc welding is used from the center to the surrounding area. The welding current is 170A, the voltage is 23V, and the welding rod is E5015. The welding speed is controlled to be 30cm / min. After welding, the welding tightness and flatness are checked, and the flatness deviation is controlled within ±1mm.

[0027] S500, grouting operation: after completing the end sealing plate welding, grouting operation is carried out through the grouting hole. The grouting operation adopts a step-by-step vibration grouting process. According to the requirements of the grouting material mix ratio, the cement, aggregate, and admixture raw materials are weighed, and the mixed grouting material is grouted through the grouting equipment. The first grouting volume is controlled between 1 / 3-1 / 2 of the volume of the connection node, and a small high-frequency vibrator is used to briefly vibrate the connection node. The vibration frequency is set between 100-150 Hz and the vibration time is 10-20 seconds. After the vibration is completed, the grouting operation is repeated until the grouting material is close to the top of the grouting hole, 50-100mm away from the top of the hole, and the vibrator is used to vibrate again. After the grouting is completed, the connection node is maintained.

[0028] In the high-rise office building project, the connection method of the present invention cooperates closely with each step from internal partition processing to grouting and maintenance, ensures the stability of the internal partition material and processing, strictly controls the welding parameters of the steel bar connector, accurately connects the vertical main reinforcement, effectively controls the deformation of the end sealing plate, and scientifically and reasonably ensures the overall reliable connection between the concrete column and the steel column, meets the structural design requirements, and provides a solid foundation for the safety and stability of the high-rise office building. Example

[0029] Connection between concrete columns and steel columns in commercial complex buildings Project background and connection node design: The structural construction of a large commercial complex building has a complex internal space layout and variable structural stress conditions. The cross-sectional dimensions of the concrete column are 700mm×700mm, and the steel column is an H-shaped steel column with a cross-sectional specification of H600×250×12×20. The connection node is located near the atrium of the shopping mall, where there is a large flow of people and extremely high requirements for the safety and stability of the structure. It is necessary to ensure that the concrete column and the steel column are reliably connected and can withstand various complex load combinations.

[0030] Connection method steps: S100, installation and treatment of inner partitions. The inner partitions are made of high-strength low-alloy structural steel with a yield strength of 360MPa and a tensile strength of 500MPa. The surface of the inner partitions is roughened. A spray gun is used to evenly spray hard particles with a particle size of 60 microns at a pressure of 0.55MPa at a distance of 28 cm from the surface of the inner partition. The treated inner partitions are installed at a position where the steel columns exceed 1 / 3 of the net height of the floor (about 2.5 meters, the net height of the floor is 7.5 meters). Intermittent welding is used for preliminary fixation. The weld length is 45mm and the spacing is 130mm. A grouting hole with a diameter of 35mm is opened in the middle of the inner partition.

[0031] S200, welding and processing of steel bar connectors. The steel bar connectors are made of high-strength alloy steel with a yield strength of not less than 430MPa and a tensile strength of not less than 600MPa and are heat-treated. According to the positioning requirements of the vertical main reinforcement of the concrete column (the diameter of the main reinforcement is 28mm), the welding position of the steel bar connector is accurately measured and marked on the installed inner partition, and the error is controlled within ±2mm. The weld reinforcement agent is based on epoxy resin (36% by mass), with 26% of curing agent, 13% of iron powder, 9% of rare earth elements and 12% of solvent added. Carbon dioxide gas shielded welding is used for welding. The welding current is 205A, the voltage is 24.5V, and the welding speed is 42cm / min. After welding, appearance and ultrasonic flaw detection are carried out. After passing the inspection, the weld is hammered with a hammer force of 2.5kN, a hammer frequency of 2.8 times / second, and two hammering times.

[0032] S300, vertical main reinforcement connection, connect the bottom of the vertical main reinforcement of the concrete column with the welded steel bar connector, the side of the vertical main reinforcement and the vertical main reinforcement positioning plate are welded by manual arc welding, the welding current is 165A, the voltage is 22.5V, the welding rod is E4303, the welding length is 280mm, the vertical main reinforcement positioning plate is made of Q345B steel plate with a thickness of 11mm, the main reinforcement positioning groove on the positioning plate is made of CNC processing technology, and the size accuracy of the positioning groove is controlled within ±0.5mm. The welding is carried out in multiple layers and multiple passes, the thickness of each layer of weld does not exceed 4mm, the width of each weld does not exceed 10mm, and the interlayer temperature is controlled not to exceed 200℃ during welding.

[0033] S400, installation and welding of end sealing plates. The end sealing plates are made of 16mm thick stainless steel plates. A grouting hole with a diameter of 35mm and an operating hole with a square size of 180mm are opened in the middle of the sealing plates. Reinforcement holes are accurately set around the sealing plates according to the positions of the vertical main reinforcements. The hole diameter is 4mm larger than the diameter of the main reinforcement. According to the principles of structural mechanics and ANSYS software, the subsequent actual stress state of the connection node between the steel column and the concrete column is simulated and calculated. It is determined that the reverse deformation amount that the end sealing plate needs to generate in advance is 2.5mm, and the deformation direction is upward. A special hydraulic jack is used to perform reverse deformation on the end sealing plate. The deformation process is monitored by a total station. The pre-deformed end sealing plate is placed at the predetermined position of the steel column head. Manual arc welding is used to weld from the center to the surroundings. The welding current is 175A, the voltage is 23.5V, and the welding rod is E5015. The welding speed is controlled to be 32cm / min. After welding, the welding tightness and flatness are checked, and the flatness deviation is controlled within ±1mm.

[0034] S500, grouting operation After completing the end sealing plate welding, grouting operation is carried out through the grouting hole. The grouting material mix ratio is cement: aggregate: admixture = 1:2.2:0.06 (mass ratio). After accurately weighing the raw materials, the mixed grouting material is grouted through the grouting equipment. The first grouting amount is controlled at 40% of the volume of the connection node. After the first grouting is completed, a small high-frequency vibrator is immediately used to briefly vibrate the connection node. The vibration frequency is set to 130 Hz and the vibration time is 16 seconds. After the vibration is completed, the grouting operation is continued until the grouting material approaches the top of the grouting hole, about 70 mm away from the top of the hole. The vibrator is used for vibration again, and the vibration parameters are the same as the first time. After the grouting is completed, the connection node is cured. The curing temperature is controlled at 21°C and the humidity is not less than 92%. The curing time is 7.5 days.

[0035] In commercial complex buildings, each link of the connection method of the present invention is closely linked, the internal partitions and steel bar connectors are accurately processed, the vertical main reinforcements are firmly connected, the end sealing plates are welded in place, the grouting operation is rigorous, and each step is effectively executed to meet the structural safety requirements, provide reliable protection for the building under complex stress, and provide a useful reference for the connection of similar buildings.

[0036] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

Claims

1. A method for connecting a concrete column and a concrete-filled steel tube column, characterized in that: The specific steps of this connection method are: S100, installation and treatment of inner partition: The height of the steel column exceeds 1 / 3 of the net height of the floor, and the inner partition is installed on the floor slab at this position. A grouting hole with a diameter of 20-50 mm is opened in the middle of the inner partition; S200, welding and treatment of steel bar connectors: according to the requirements for positioning the vertical main reinforcement of the concrete column, measure and mark the welding position of the steel bar connector on the installed inner partition, and control the error within ±2mm. Apply weld reinforcement agent at the welding point between the steel bar connector and the inner partition, with a thickness of 0.5-1.5mm. The steel bar connector is welded by carbon dioxide gas shielded welding, with a welding current of 180-220A, a voltage of 22-26V, and a welding speed of 30-50cm / min. After welding, perform appearance and ultrasonic flaw detection; S300, vertical main reinforcement connection: connect the bottom of the vertical main reinforcement of the concrete column with the welded steel bar connector, and use manual arc welding for the side of the vertical main reinforcement and the vertical main reinforcement positioning plate. The welding current is 150-180A, the voltage is 20-24V, the welding rod is E4303, and the welding length is 10d, where d is the diameter of the vertical main reinforcement; S400, installation and welding of end sealing plates: according to the size and shape of the steel column head, the end sealing plates are processed and manufactured. Before welding the end sealing plates on the steel column head, the reverse deformation amount and direction are determined according to structural mechanics analysis and simulation calculation. A special hydraulic jack is used to perform reverse deformation on the end sealing plates. The deformation process is monitored by a total station. The pre-deformed end sealing plates are placed at the predetermined position of the steel column head. Manual arc welding is used from the center to the surroundings. The welding current is 160-190A, the voltage is 21-25V, and the welding rod is E5015 type. The welding speed is controlled to be 25-35cm / min. After welding, the welding tightness and flatness are checked, and the flatness deviation is controlled within ±1mm; S500, grouting operation: after completing the end sealing plate welding, grouting operation is carried out through the grouting hole. The grouting operation adopts a step-by-step vibration grouting process. According to the requirements of the grouting material mix ratio, the cement, aggregate, and admixture raw materials are weighed, and the mixed grouting material is grouted through the grouting equipment. The first grouting volume is controlled between 1 / 3-1 / 2 of the volume of the connection node, and a small high-frequency vibrator is used to briefly vibrate the connection node. The vibration frequency is set between 100-150 Hz and the vibration time is 10-20 seconds. After the vibration is completed, the grouting operation is repeated until the grouting material is close to the top of the grouting hole, 50-100mm away from the top of the hole, and the vibrator is used to vibrate again. After the grouting is completed, the connection node is maintained.

2. A method for connecting a concrete column and a concrete-filled steel tube column according to claim 1, characterized in that: In the S100, the material of the inner partition during the installation and treatment of the inner partition is high-strength low-alloy structural steel, with a yield strength of not less than 345MPa and a tensile strength of not less than 470MPa. Before installing the inner partition, the surface of the inner partition is subjected to a special roughening treatment, and the inner partition is placed on a dedicated processing platform. A spray gun is used to evenly spray hard particles with a particle size of 10-100 microns at a pressure of 0.4-0.6MPa at a distance of 20-30 cm from the surface of the inner partition.

3. The method for connecting a concrete column and a concrete-filled steel tube column according to claim 1, characterized in that: In the above S100, the processed inner partition is installed at the predetermined position of the steel column during the installation and processing of the inner partition, and is initially fixed by intermittent welding, with the weld length being 30-50 mm and the spacing being 100-150 mm.

4. The method for connecting a concrete column and a concrete-filled steel tube column according to claim 1, characterized in that: The S200, weld reinforcement agent in the welding and processing of steel bar connectors is based on epoxy resin, which accounts for 30%-40% by mass; 20%-30% of curing agent is added; it contains 10%-15% iron powder; 5%-10% rare earth elements; and 10%-20% solvent.

5. The method for connecting a concrete column and a concrete-filled steel tube column according to claim 1, characterized in that: In the above S200, during the welding and processing of the steel bar connector, the steel bar connector is made of high-strength alloy steel, the yield strength of which is not less than 400MPa and the tensile strength is not less than 550MPa.

6. The method for connecting a concrete column and a concrete-filled steel tube column according to claim 1, characterized in that: In the S200, in the welding and processing of the steel bar connector, after the welding of the steel bar connector is completed, the weld is hammered, the hammering force is 1-3kN, the hammering frequency is 2-3 times / second, and the number of hammering times is 2-3 times.

7. The method for connecting a concrete column and a concrete-filled steel tube column according to claim 1, characterized in that: In the S300, the vertical main reinforcement positioning plate in the vertical main reinforcement connection is made of Q345B steel plate with a thickness of 8-12mm, and the main reinforcement positioning groove on the positioning plate is processed by CNC technology, and the dimensional accuracy of the positioning groove is controlled within ±0.5mm.

8. The method for connecting a concrete column and a concrete-filled steel tube column according to claim 1, characterized in that: In the S300, when the vertical main reinforcement is connected and the vertical main reinforcement is welded to the vertical main reinforcement positioning plate, the welding is performed in a multi-layer and multi-pass manner, the thickness of each layer of weld is not more than 4 mm, the width of each pass of weld is not more than 10 mm, and the interlayer temperature is controlled not to exceed 200° C. during the welding process.

9. The method for connecting a concrete column and a concrete-filled steel tube column according to claim 1, characterized in that: For the S400, the end sealing plate is made of a stainless steel plate with a thickness of 12-18 mm during installation and welding. A grouting hole with a diameter of 20-50 mm and an operating hole with a square size of 100-200 mm are opened in the middle of the sealing plate. Reinforcement holes are accurately set around the sealing plate according to the position of the vertical main reinforcement, and the hole diameter is 2-5 mm larger than the diameter of the main reinforcement.

10. The method for connecting a concrete column and a concrete-filled steel tube column according to claim 1, characterized in that: In the S400, the welding pre-deformation of the end cover plate is calculated during the installation and welding of the end cover plate, and the finite element analysis software ANSYS is used to simulate the subsequent actual stress condition of the connection node between the steel column and the concrete column, and analyze the deformation trend and deformation amount of the position of the end cover plate when the node is subjected to various expected loads.

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