A double-stage energy-absorbing steel tube concrete column-wide flat beam node structure and construction method

Abstract

The present invention discloses a double-stage energy-absorbing steel tube concrete column-wide flat beam node structure, comprising a steel tube concrete column in the vertical direction, a prefabricated wide flat beam in the horizontal direction, and a double-stage energy-absorbing section. The steel tube concrete column and the prefabricated wide flat beam are connected by the double-stage energy-absorbing section. The double-stage energy-absorbing section includes a friction energy-absorbing device and two metal energy-absorbing devices. The two metal energy-absorbing devices are bolted side by side between the first end plate of the steel tube concrete column and the third end plate of the prefabricated wide flat beam. The friction energy-absorbing device is arranged between the two metal energy-absorbing devices and is bolted to the first end plate of the steel tube concrete column and the third end plate of the prefabricated wide flat beam, respectively. The present invention also discloses a construction method for a double-stage energy-absorbing steel tube concrete column-wide flat beam node structure, which solves the problems of poor energy-absorbing effect and high repair cost of traditional nodes under earthquake action. The structure has rapid recovery after an earthquake and can be widely used in beam-column nodes of underground structures.

Description

Technical Field

[0001] The present invention relates to a steel tube concrete column-wide flat beam node structure and a construction method for an underground space structure, and in particular to a double-stage energy-absorbing steel tube concrete column-wide flat beam node structure and a construction method, belonging to the technical field of underground space structures. Background Art

[0002] With the rapid growth of urban populations and the increasing scarcity of land resources, developing urban underground space has become a crucial approach to alleviating resource shortages. This not only improves the supply of urban transportation and infrastructure, but also conserves land and improves the environment. Existing underground structures mostly utilize frame structures. Due to the difficulty and uncertainty of excavation, wide and flat reinforced concrete beams are often used to increase clearance and reduce costs. Concrete-filled steel tubular columns are favored for their high bearing capacity and good ductility. However, under earthquake action, the vulnerable link in the frame system is often the joint core area. Failure of this joint core area disrupts the force balance between beams and columns, affecting the bearing capacity of the entire frame, leading to structural collapse or damage. In such cases, repair is difficult or costly, necessitating demolition and reconstruction, resulting in significant property losses. To address this situation, traditional underground structure design methods and the connection joints between concrete-filled steel tubular columns and wide and flat beams no longer meet the requirements of green industrialization and sustainable development. Therefore, the seismic design of underground structures is gradually shifting towards replaceable and high-energy-consumption structures. Summary of the Invention

[0003] In order to solve the problems of poor energy dissipation effect and high repair cost of traditional nodes under earthquake action, the present invention proposes a double-stage energy-absorbing steel tube concrete column-wide flat beam node structure and construction method, which has the ability to quickly recover after an earthquake.

[0004] The technical solution adopted by the present invention to solve the above problems is:

[0005] A double-stage energy-absorbing steel tube concrete column-wide flat beam node structure, comprising a steel tube concrete column in a vertical direction, a prefabricated wide flat beam in a horizontal direction and a double-stage energy-absorbing section, wherein the steel tube concrete column and the prefabricated wide flat beam are connected via the double-stage energy-absorbing section, the double-stage energy-absorbing section comprising a friction energy-absorbing device and two metal energy-absorbing devices, the two metal energy-absorbing devices are bolted side by side and parallel between the first end plate of the steel tube concrete column and the third end plate of the prefabricated wide flat beam, the friction energy-absorbing device is arranged between the two metal energy-absorbing devices and respectively bolted to the first end plate of the steel tube concrete column and the third end plate of the prefabricated wide flat beam, the third end plate is provided with a first ear plate, the friction energy-absorbing device comprises a hinge bolt, a nut matching the hinge bolt, four a friction plate, four friction steel plates, two disc springs, two disc spring limit plates, two first ear plates, two second ear plates and two steel blocks, wherein one end of the first ear plate is rectangular and the other end is semicircular, a bolt hole is opened on the rectangular side, a bolt hole is opened at the center of the semicircular side and annular grooves are provided on both sides, the friction plates are respectively installed in the annular grooves of the first ear plates of the friction energy dissipation device, the shape of the friction plates is annular and conforms to the shape of the annular grooves of the first ear plates, the two first ear plates of the friction energy dissipation device are arranged side by side in parallel, the first ear plate on the third end plate is located between the two first ear plates of the friction energy dissipation device and the semicircular ends are arranged opposite to each other, and the second Ear plate, one end of the second ear plate is rectangular and the other end is semicircular, a bolt hole is opened on the rectangular side, a bolt hole is opened at the center of the semicircular side, and a circular ring groove is provided near the side of the first ear plate, the friction steel plate is installed in the circular ring groove of the second ear plate, and the friction steel plates are respectively installed in the circular ring grooves on both sides of the first ear plate on the third end plate, the shape of the friction steel plate is a circular ring that conforms to the shape of the circular ring groove of the second ear plate, the semicircular end of the first ear plate is arranged opposite to the semicircular end of the second ear plate, the disc springs are respectively installed on the outside of the two second ear plates, and disc spring limiting plates are respectively installed on the outside of the two disc springs, the cross-sectional shape of the disc spring and the disc spring limiting plate is a circular ring, and the hinged bolts pass through in sequence The disc spring limiting plate, disc spring, second ear plate, friction steel plate, friction plate, the first ear plate of the friction energy dissipation device, friction plate, friction steel plate, the first ear plate on the third end plate, friction steel plate, friction plate, the first ear plate of the friction energy dissipation device, friction plate, friction steel plate, second ear plate, disc spring, and disc spring limiting plate are connected with the hinged bolts and matching nuts. The metal energy dissipation device includes a low yield point steel plate, two anti-buckling steel plates, two strip steel plates, a number of bolts and a number of nuts. The two strip steel plates are respectively welded to the two sides of the low yield point steel plate. Bolt holes are provided on the strip steel plates. The height of the low yield point steel plate is equal to the height of the prefabricated wide flat beam. Trapezoidal grooves are provided on both sides of the low yield point steel plate.The invention comprises a straight section of a low-yield point steel plate and an oblique straight section of a low-yield point steel plate, wherein a plurality of parallel rectangular through holes are provided on the low-yield point steel plate, and the two anti-buckling steel plates are respectively provided on both sides of the low-yield point steel plate, and the two sides of the anti-buckling steel plate are olive-shaped, and the side close to the low-yield point steel plate is trapezoidal, comprising a straight section of the anti-buckling steel plate and an oblique straight section of the anti-buckling steel plate, and the side of the anti-buckling steel plate close to the low-yield point steel plate is conformed to the trapezoidal groove provided on the low-yield point steel plate, and the rectangular groove on the low-yield point steel plate is formed. The horizontal length of the rectangular through-hole is greater than the length of the straight section and the oblique straight section of the anti-buckling steel plate in the same horizontal direction. The side of the anti-buckling steel plate is provided with multiple bolt holes, the positions of the bolt holes correspond to the rectangular through-holes of the low-yield point steel plate, and the diameter of the bolt holes is equal to the height of the rectangular through-holes of the low-yield point steel plate. The low-yield point steel plate and the anti-buckling steel plate are connected by bolts. After connection, the distance between the end of the straight section of the low-yield point steel plate and the two strip steel plates meets the ultimate compression capacity of the low-yield point steel plate.

[0006] Furthermore, the limit length of the anti-buckling steel plate can be calculated according to the connection method between the low yield point steel plate and the anti-buckling steel plate. The calculation formula is as follows:

[0007]

[0008] Where, is the distance between the end of the straight section of the low yield point steel plate and the left strip steel plate, is the horizontal length of the straight section of the low yield point steel plate, is the distance between the end of the straight section of the low yield point steel plate and the right strip steel plate, is the strain of the low yield point steel plate.

[0009] Furthermore, the friction plate and the friction steel plate have the same shape.

[0010] Furthermore, the steel tube concrete column includes core concrete, a steel tube, two first end plates and multiple PVC tubes. The core concrete is poured into the steel tube. The cross-section of the first end plate is in a convex shape, including a fixed section and a middle section. The fixed sections of the two first end plates are respectively welded to the steel tube close to the side of the prefabricated wide flat beam. The multiple PVC tubes are installed on the remaining two sides of the steel tube after concrete pouring.

[0011] Furthermore, bolt holes are respectively provided on the middle section of the first end plate and on both sides of the fixed section, and the width of the fixed section of the first end plate is greater than the width of the steel pipe.

[0012] Furthermore, the prefabricated wide flat beam includes steel bars, concrete, an I-beam, a plurality of shear nails, a second end plate, stiffening ribs and a third end plate. The steel bars and the concrete constitute the beam body of the prefabricated wide flat beam. The I-beam is embedded in the end of the prefabricated wide flat beam. A plurality of the shear nails are arranged on the upper and lower flanges of the I-beam. The end of the I-beam is welded to the second end plate. The other side of the second end plate is welded with longitudinal bars in the horizontal direction and the stiffening ribs in the vertical direction. The other side of the longitudinal bars and the stiffening ribs is welded to the third end plate.

[0013] Furthermore, the cross-section of the second end plate is rectangular, and the cross-section size is equal to the cross-section size of the prefabricated wide flat beam.

[0014] Furthermore, the third end plate also includes a steel plate, the cross-section of the steel plate is rectangular, bolt holes are opened on both sides of the steel plate, the rectangular side of the first ear plate on the third end plate is welded to the steel plate in the center, and the side of the steel plate to which the first ear plate is not welded is welded to the longitudinal reinforcement and the stiffening rib.

[0015] Furthermore, the cross-sectional size of the steel plate is equal to the cross-sectional size of the prefabricated wide flat beam.

[0016] Furthermore, two metal energy dissipation devices are bolted side by side in parallel between the first end plate of the steel tube concrete column and the third end plate of the prefabricated wide flat beam, and the strip steel plates on the two side sides of the low yield point steel plate of the metal energy dissipation device are bolted to the fixed section of the first end plate on one side and bolted to the steel plate of the third end plate on the other side.

[0017] Furthermore, the height of the strip steel plate is equal to the height of the prefabricated wide flat beam.

[0018] Furthermore, the rectangular sides of the two first ear plates of the friction energy dissipation device are fixedly connected with the middle section of the first end plate by bolts, and the steel block is a rectangular steel block with bolt holes provided on it, through which the second ear plate is bolted to the rectangular side of the first ear plate on the third end plate.

[0019] A construction method for a double-stage energy-absorbing steel tube concrete column-wide flat beam node structure is achieved by the following steps:

[0020] Step 1: Make concrete-filled steel tube columns and prefabricated wide flat beams;

[0021] Step 2: Connect the friction energy dissipation device and bolt the friction energy dissipation device to the steel tube concrete column and the prefabricated wide flat beam;

[0022] Step 3: Apply pre-tightening force to the friction energy dissipation device installed in step 2, and then connect the metal energy dissipation device with the steel tube concrete column and the prefabricated wide flat beam bolts.

[0023] The beneficial effects of the present invention are:

[0024] 1. Under the action of an earthquake, the present invention can achieve the effect of dual-stage energy dissipation by rotating the friction energy dissipation device in the case of a small earthquake, and by plastic deformation of the metal energy dissipation device in the case of a medium or large earthquake.

[0025] 2. The friction energy dissipation device of the present invention is easy to install and the friction plate is easy to replace. The combined friction energy dissipation device can fully utilize the friction plate and reduce the problem of the friction plate not being fully used due to deformation caused by installation.

[0026] 3. After a moderate or severe earthquake, if the metal energy dissipation device undergoes plastic deformation and fails, the present invention directly replaces the metal energy dissipation device, restoring the structure's existing mechanical properties. The buckling-resistance steel plates in the metal energy dissipation device prevent buckling of the internal low-yield point steel plates, maximizing tensile and compressive deformation, thereby effectively dissipating the structure's energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a structural schematic diagram of an embodiment of a double-stage energy-absorbing steel tube concrete column-wide flat beam node structure of the present invention;

[0028] Figure 2 yes Figure 1 Front view of

[0029] Figure 3 yes Figure 1 A top view of

[0030] Figure 4 It is a structural schematic diagram of an embodiment of the double-stage energy dissipation section of the present invention;

[0031] Figure 5 It is a structural schematic diagram of an embodiment of the friction energy dissipation device of the present invention;

[0032] Figure 6 It is a structural schematic diagram of an embodiment of the metal energy dissipation device of the present invention;

[0033] Figure 7 This is a structural diagram of an embodiment of a steel tube concrete column of the present invention;

[0034] Figure 8 This is a structural schematic diagram of an embodiment of the prefabricated wide flat beam of the present invention;

[0035] Figure 9 is a structural schematic diagram of an embodiment of the first end plate of the present invention;

[0036] Figure 10 It is the force diagram of the metal energy dissipation device of the present invention;

[0037] Figure 11 This is a schematic structural diagram of an embodiment of a low yield point steel plate of a metal energy dissipation device of the present invention;

[0038] Figure 12 It is a structural schematic diagram of an embodiment of the present invention in which a friction energy dissipation device is connected to a steel tube concrete column and a prefabricated wide flat beam.

[0039] In the figure: 1. Steel tube concrete column; 2. Prefabricated wide flat beam; 3. Two-stage energy dissipation section; 4. Friction energy dissipation device; 5. Metal energy dissipation device; 6. Hinged bolt; 7. Hinged bolt matching nut; 8. Friction plate; 9. Friction steel plate; 10. Disc spring; 11. Disc spring limit plate; 12. First ear plate; 13. Second ear plate; 14. Steel block; 15. Low yield point steel plate; 16. Anti-buckling steel plate; 17. Strip steel plate; 18. Core concrete; 19. Steel pipe; 20. First end plate; 21. PVC pipe; 22. Steel bar; 23. Concrete; 24. Shear nail; 25. I-beam; 26. Second end plate; 27. Stiffening rib; 28. Third end plate; 29. ​​Steel plate. DETAILED DESCRIPTION

[0040] In the description of the present invention, it should be noted that all directional indications (such as horizontal, vertical, etc.) are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, they cannot be understood as limiting the present invention.

[0041] Specific implementation method 1: Combination Figure 1-10 To explain this embodiment,

[0042] like Figure 1-4 As shown, the double-stage energy-absorbing steel tube concrete column-wide flat beam node structure described in this embodiment includes a vertical steel tube concrete column 1, a horizontal prefabricated wide flat beam 2 and a double-stage energy-absorbing section 3. The steel tube concrete column 1 and the prefabricated wide flat beam 2 are connected through the double-stage energy-absorbing section 3. The double-stage energy-absorbing section 3 includes a friction energy-absorbing device and two metal energy-absorbing devices. The two metal energy-absorbing devices are bolted side by side in parallel between the first end plate 20 of the steel tube concrete column 1 and the third end plate 28 of the prefabricated wide flat beam 2. The friction energy-absorbing device is arranged between the two metal energy-absorbing devices and is bolted to the first end plate 20 of the steel tube concrete column 1 and the third end plate 28 of the prefabricated wide flat beam 2 respectively.

[0043] like Figure 9As shown, the cross-section of the first end plate 20 is in a convex shape, including a fixed section and a middle section. Bolt holes are respectively provided on the middle section and on both sides of the fixed section. The bolt holes provided on the middle section are used to install the friction energy dissipation device, and the bolt holes on both sides of the fixed section are used to install the metal energy dissipation device. The number of the bolt holes can be one or several, preferably several. The several bolt holes are arranged at equal intervals along the vertical direction of the first end plate 20. It is best to have three bolt holes to improve the fixing effect of the device.

[0044] The third end plate 28 comprises a steel plate 29 and a first lug plate 12. The steel plate 29 is a rectangular plate with a rectangular cross-section. Preferably, the cross-section of the steel plate 29 is equal to that of the prefabricated wide flat beam 2, thereby improving the stability of the prefabricated wide flat beam 2. Bolt holes are provided on both sides of the steel plate 29 for mounting the metal energy dissipation device. Preferably, there are multiple bolt holes, evenly spaced along the vertical direction of the steel plate 29. Three bolt holes are preferably provided to enhance the device's securement.

[0045] The first lug 12 is rectangular at one end and semicircular at the other. Bolt holes are provided on the rectangular side. Preferably, there are multiple bolt holes, evenly spaced vertically along the rectangular side of the first lug 12. Three bolt holes are ideal for enhancing the device's securement. A bolt hole is provided at the center of the semicircular side of the first lug 12, with annular grooves on either side. The rectangular side of the first lug 12 of the third end plate 28 is welded centrally to the steel plate 29. This rectangular side of the first lug 12 of the third end plate 28 is used to mount the friction energy dissipation device.

[0046] like Figure 7 As shown, the CFST column 1 includes a core concrete 18, a steel tube 19, two first end plates 20, and multiple PVC tubes 21. The core concrete 18 is poured within the steel tube 19. The fixed sections of the two first end plates 20 are welded to the steel tube 19 near the side of the precast wide flat beam 2. The width of the fixed section of the first end plate 20 is greater than the width of the steel tube 19. The multiple PVC tubes 21 are installed on the remaining two sides of the steel tube 19 after concrete pouring. The PVC tubes 21 are symmetrically and evenly arranged on both sides of the CFST column, and their length is equal to the side length of the cross-section of the CFST column.

[0047] like Figure 8As shown, the prefabricated wide flat beam 2 includes steel bars 22, concrete 23, an I-beam 25, a plurality of shear nails 24, a second end plate 26, a stiffening rib 27 and a third end plate 28. The steel bars 22 and the concrete 23 constitute the beam body of the prefabricated wide flat beam 2. The I-beam 25 is embedded in the end of the prefabricated wide flat beam 2. A plurality of the shear nails 24 are arranged on the upper and lower flanges of the I-beam 25. Preferably, the cross-section of the shear nail 24 is T-shaped, and the height is one-fourth of the I-beam 25. The bottom of the shear nail 24 is welded to the I-beam and is symmetrically and evenly arranged on the upper and lower flanges of the I-beam. The length of the I-beam 25 is one-sixth of the length of the prefabricated wide flat beam 2, and the height is one-half of the length of the prefabricated wide flat beam 2. The end of the I-beam 25 is welded to the second end plate 26. Preferably, the cross-section of the second end plate 26 is rectangular, and the cross-section size is equal to the cross-section size of the prefabricated wide flat beam. The other side of the second end plate 26 is welded with longitudinal bars in the horizontal direction and the stiffening ribs 27 in the vertical direction. The second end plate 26 is welded to the third end plate 28 on the other side of the longitudinal bars and the stiffening ribs 27. Preferably, there are multiple longitudinal bars, and the multiple longitudinal bars are arranged in parallel at equal intervals along the vertical direction of the second end plate 26. The number of the stiffening ribs 27 is multiple, and the multiple stiffening ribs 27 are arranged in parallel at equal intervals along the horizontal direction of the second end plate 26, so that the prefabricated wide flat beam 2 is more stable.

[0048] like Figure 5As shown, the friction energy dissipation device includes a hinged bolt 6, a matching nut 7 for the hinged bolt, four friction plates 8, four friction steel plates 9, two disc springs 10, two disc spring stoppers 11, two first lugs 12, two second lugs 13, and two steel blocks 14. The two first lugs 12 of the friction energy dissipation device are arranged side by side and parallel to each other. The rectangular sides of the two first lugs 12 are bolted to the middle section of the first end plate 20. The friction plates 8 are mounted in the annular grooves of the first lugs 12. The friction plates 8 are annular in shape, matching the annular grooves of the first lugs 12. A second lug 13 is mounted on the outer side of each first lug 12 of the friction energy dissipation device. The second lug 13 has a rectangular shape at one end and a semicircular shape at the other. Bolt holes are provided on the rectangular side, a bolt hole is provided at the center of the semicircular side, and an annular groove is provided on the side near the first lug 12. The second lug 13 differs from the first lug 12 in that one side has an annular groove. The friction steel plates 9 are mounted in the annular grooves of the second lugs 13. The friction steel plates 9 are annular in shape, conforming to the annular grooves of the second lugs 13. The friction plates 8 have the same shape as the friction steel plates 9. The circular grooves formed in the sides of the first and second lugs 12, 13 more effectively secure the positions of the friction plates and the friction steel plates, facilitating installation and fully utilizing the friction plates, thereby reducing inadequate use of the friction plates due to deformation during installation.

[0049] The disc springs 10 are mounted on the outsides of the two second lugs 13, and disc spring stop plates 11 are mounted on the outsides of the two disc springs 10. The disc springs 10 and disc spring stop plates 11 have circular cross-sectional shapes. The semicircular end of the first lug 12 of the friction energy dissipation device is positioned opposite the semicircular end of the second lug 13. The first lug 12 on the third end plate 28 is positioned between the two first lugs 12 of the friction energy dissipation device, with the semicircular ends facing each other. The friction steel plates 9 are mounted in the circular grooves on both sides of the first lug 12 on the third end plate 28. The steel block 14 is a rectangular steel block with bolt holes formed therein. Bolts are used to connect the second lug 13 to the rectangular side of the first lug 12 on the third end plate 28 through the steel block 14. Preferably, the number of bolt holes in the steel block 14 is the same as the number of bolt holes on the rectangular side of the second lug 13 and the rectangular side of the first lug 12 on the third end plate 28. The arrangement of the steel block 14 facilitates the connection between the second ear plate 13 and the first ear plate 12 on the third end plate 28 . At the same time, the connection between the second ear plate 13 and the first ear plate 12 on the third end plate 28 is adjustable, thereby avoiding uneven heating due to welding, thereby making the friction of the friction energy dissipation device more sufficient.

[0050] like Figure 12 As shown, the hinge bolt 6 passes through the disc spring limiting plate 11, disc spring 10, second ear plate 13, friction steel plate 9, friction plate 8, first ear plate 12, friction plate 8, friction steel plate 9, first ear plate 12, friction steel plate 9, friction plate 8, first ear plate 12, friction plate 8, friction steel plate 9, second ear plate 13, disc spring 10, and disc spring limiting plate 11 in sequence, and is connected to the hinge bolt matching nut 7. The hinge bolt 6 connects the friction energy dissipation device to the third end plate 28. The arrangement of the hinge bolt 6 and the hinge bolt matching nut 7 makes the overall structure of the friction energy dissipation device more compact and the connection more seamless, thereby making the friction effect of the friction energy dissipation device more uniform.

[0051] like Figure 6 As shown, the metal energy dissipation device includes a low-yield point steel plate 15, two anti-buckling steel plates 16, two strip steel plates 17, a number of bolts and a number of nuts. The two strip steel plates 17 are respectively welded to the two sides of the low-yield point steel plate 15. Preferably, the height of the strip steel plate 17 is equal to the height of the prefabricated wide flat beam 2, which is convenient for the installation of the metal energy dissipation device. Bolt holes are provided on the strip steel plate 17, and the strip steel plate 17 is bolted to the fixed section of the first end plate 20. Preferably, the number of bolt holes provided on the strip steel plate 17 is the same as the number provided on the fixed section of the first end plate 20, which is convenient for installation.

[0052] like Figure 11 As shown, the height of the low-yield point steel plate 15 is equal to that of the prefabricated wide flat beam 2. Trapezoidal grooves are formed on both sides of the low-yield point steel plate 15, including a straight section and an oblique straight section. The low-yield point steel plate 15 is provided with a plurality of parallel rectangular through-holes. Preferably, the low-yield point steel plate 15 is made of LY160, which has a yield point of less than 200 MPa. Because the bending moment on both sides is greater and the bending moment in the middle is smaller, the cross-section is funnel-shaped, which can fully utilize the material.

[0053] The two anti-buckling steel plates 16 are respectively arranged on both sides of the low-yield point steel plate 15. The two sides of the anti-buckling steel plate 16 are olive-shaped, and the side close to the low-yield point steel plate 15 is trapezoidal, including a straight section of the anti-buckling steel plate and an oblique straight section of the anti-buckling steel plate. The side of the anti-buckling steel plate 16 close to the low-yield point steel plate 15 is conformal to the trapezoidal groove opened in the low-yield point steel plate 15. The horizontal length of the rectangular through hole on the low-yield point steel plate 15 is greater than the length of the straight section and the oblique straight section of the anti-buckling steel plate in the same horizontal direction. A plurality of bolt holes are opened on the side of the anti-buckling steel plate 16. The positions of the bolt holes correspond to the rectangular through holes of the low-yield point steel plate 15. The diameters of the bolt holes are equal to the height of the rectangular through holes of the low-yield point steel plate 15. The low-yield point steel plate 15 and the anti-buckling steel plate 16 are connected by bolts. Preferably, the height of the rectangular through-holes on the straight section of the low-yield point steel plate is greater than the diameter of the rectangular through-holes on the oblique straight section of the low-yield point steel plate, so that fewer bolt holes can be opened on the straight section of the low-yield point steel plate, thereby making the anti-buckling steel plate 16 more effective in preventing the internal low-yield point steel plate 15 from buckling deformation. The anti-buckling steel plate 16 is made of Q355B steel, which can prevent the anti-buckling steel plates 16 on both sides from sliding downward. The distance between the connected straight section of the low-yield point steel plate and the end of the straight section of the low-yield point steel plate from the two strip steel plates 17 meets the ultimate compression of the low-yield point steel plate 15, which can make better use of the material and achieve the best energy consumption effect.

[0054] like Figure 10 As shown, the limit length of the anti-buckling steel plate 16 can be calculated according to the connection method of the low yield point steel plate 15 and the anti-buckling steel plate 16. The expression is as follows:

[0055]

[0056] Where, is the distance between the end of the straight section of the low yield point steel plate and the left strip steel plate, is the horizontal length of the straight section of the low yield point steel plate, is the distance between the end of the straight section of the low yield point steel plate and the right strip steel plate, is the strain of the low yield point steel plate.

[0057] The dual-stage energy dissipation section changes the working mode of the structure, and has different seismic resistance effects in the face of earthquakes of different levels. In the case of small earthquakes, friction energy dissipation consumes the energy of the earthquake through rotational friction to ensure that the structure is not damaged. In the case of medium and large earthquakes, the low-yield point steel plates in the metal energy dissipation consume the energy of the earthquake through plastic deformation. This node classifies the energy consumption according to the earthquake levels, and the energy dissipation capacity is greatly improved to achieve a good seismic resistance effect. The dual-stage energy dissipation section does not cause damage in small earthquakes, but consumes energy and causes damage first in medium and large earthquakes, and can be replaced after damage.

[0058] A construction method for a double-stage energy-absorbing steel tube concrete column-wide flat beam node structure is achieved by the following steps:

[0059] Step 1: Fabricate the concrete-filled steel tube column 1 and the prefabricated wide flat beam 2. Specifically, in the factory, the prefabricated wide flat beam is assembled with a reinforcement cage, the steel tube is welded to the first-type end plate, the shear studs are welded to the I-beam, and the steel plate is welded to the first lug plate. The reinforcement cage and I-beam are then welded to one side of the second-type end plate. The second-type end plate is then welded to the stiffening rib, and the stiffening rib is welded to the third-type end plate. Formwork is then installed for the wide flat beam. Concrete is then poured for the wide flat beam and concrete-filled steel tube column. When pouring concrete for the concrete-filled steel tube column, the PVC pipe is secured in place before pouring.

[0060] Step 2: Connect the friction energy dissipation device. Bolt the friction energy dissipation device to the first end plate 20 of the concrete-filled steel tube column 1 and the third end plate 28 of the precast wide flat beam 2. Connect the first and second lugs, friction plates, friction steel plates, disc springs, disc spring stop plates, and the first lug of the third end plate with hinged bolts. Then, bolt the first and second lugs and steel blocks to the third end plate. Bolt the first and second lugs to the first-type end plate to form a single unit.

[0061] Step 3: Apply pre-tightening force to the friction energy dissipation device installed in step 2, and then bolt the metal energy dissipation device to the first end plate 20 of the steel tube concrete column 1 and the third end plate 28 of the prefabricated wide flat beam 2.

[0062] This ensures that the frictional energy dissipation components dissipate energy through rotation in the event of a minor earthquake, while the metal energy dissipation components dissipate energy through plastic deformation in the event of a moderate or severe earthquake. This structure exhibits excellent overall mechanical properties, is easy to install, has a high load-bearing capacity, strong energy dissipation capabilities, slow degradation of strength and stiffness, and good ductility. Its replaceable energy dissipation components significantly reduce repair and maintenance costs and time, and it offers rapid post-earthquake recovery, making it widely applicable to beam-column joints in underground structures. The seismic design of underground structures is gradually evolving towards replaceable, high-energy dissipation structures.

[0063] The above description is merely a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention has been disclosed as a preferred embodiment as above, it is not intended to limit the present invention. Any technician familiar with the present profession can make some changes or modifications to equivalent embodiments of equivalent changes using the technical content disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent replacement and improvement of the above embodiments made according to the technical essence of the present invention, within the spirit and principles of the present invention, without departing from the content of the technical solution of the present invention, shall still fall within the scope of protection of the technical solution of the present invention.

Claims

1. A double-stage energy-absorbing concrete-filled steel tube column-wide flat beam node structure, characterized by: The invention comprises a steel tube concrete column (1) in the vertical direction, a prefabricated wide flat beam (2) in the horizontal direction and a double-stage energy absorption section (3), wherein the steel tube concrete column (1) and the prefabricated wide flat beam (2) are connected via the double-stage energy absorption section (3), and the double-stage energy absorption section (3) comprises a friction energy absorption device and two metal energy absorption devices, wherein the two metal energy absorption devices are bolted side by side between the first end plate (20) of the steel tube concrete column (1) and the third end plate (28) of the prefabricated wide flat beam (2), and the friction energy absorption device is arranged between the two metal energy absorption devices and respectively connected to the first end plate (20) of the steel tube concrete column (1) and the third end plate (28) of the prefabricated wide flat beam (2). The third end plate (28) is connected by bolts, and a first ear plate (12) is provided on the third end plate (28). The friction energy dissipation device includes a hinged bolt (6), a hinged bolt matching nut (7), four friction plates (8), four friction steel plates (9), two disc springs (10), two disc spring limit plates (11), two first ear plates (12), two second ear plates (13) and two steel blocks (14). One end of the first ear plate (12) is rectangular and the other end is semicircular. A bolt hole is opened on the rectangular side, a bolt hole is opened at the center of the semicircular side, and an annular groove is provided on both sides. The friction plates (8) are respectively installed in the annular grooves of the first ear plate (12) of the friction energy dissipation device. The friction plate (8) is in the shape of a circular ring that matches the shape of the circular groove of the first ear plate (12). The two first ear plates (12) of the friction energy dissipation device are arranged side by side in parallel. The first ear plate (12) on the third end plate (28) is located between the two first ear plates (12) of the friction energy dissipation device and the semicircular ends are arranged opposite to each other. The second ear plates (13) are respectively installed on the outer sides of the two first ear plates (12) of the friction energy dissipation device. One end of the second ear plate (13) is rectangular and the other end is semicircular. A bolt hole is opened on the rectangular side and a bolt hole is opened at the center of the semicircular side. A circular groove is provided on the side close to the first ear plate (12). The friction steel plate (9) is installed in the annular groove of the second ear plate (13), and the friction steel plates (9) are respectively installed in the annular grooves on both sides of the first ear plate (12) on the third end plate (28). The shape of the friction steel plate (9) is an annular ring that conforms to the shape of the annular groove of the second ear plate (13). The semicircular end of the first ear plate (12) and the semicircular end of the second ear plate (13) are arranged opposite to each other. The disc springs (10) are respectively installed on the outside of the two second ear plates (13). The disc spring limiting plates (11) are respectively installed on the outside of the two disc springs (10). The cross-sectional shape of the disc spring (10) and the disc spring limiting plates (11) is annular.The hinge bolt (6) passes through the disc spring limiting plate (11), the disc spring (10), the second ear plate (13), the friction steel plate (9), the friction plate (8), the first ear plate (12) of the friction energy dissipation device, the friction plate (8), the friction steel plate (9), the first ear plate (12) on the third end plate (28), the friction steel plate (9), the friction plate (8), the first ear plate (12) of the friction energy dissipation device, the friction plate (8), the friction steel plate (9), the second ear plate (13), the disc spring (10), the disc spring limiting plate (11), and the hinge bolt matching nut (7) in sequence. ) connection, the metal energy dissipation device comprises a low yield point steel plate (15), two anti-buckling steel plates (16), two strip steel plates (17), a plurality of bolts and a plurality of nuts, the two strip steel plates (17) are respectively welded to the two sides of the low yield point steel plate (15), the strip steel plates (17) are provided with bolt holes, the height of the low yield point steel plate (15) is equal to the height of the prefabricated wide flat beam (2), the two sides of the low yield point steel plate (15) are provided with trapezoidal grooves, including a low yield point steel plate straight section and a low yield point steel plate oblique straight section, The low-yield point steel plate (15) is provided with a plurality of parallel rectangular through holes, and the two anti-buckling steel plates (16) are respectively provided on both sides of the low-yield point steel plate (15). The two sides of the anti-buckling steel plate (16) are olive-shaped, and the side close to the low-yield point steel plate (15) is trapezoidal, including a straight section of the anti-buckling steel plate and an oblique straight section of the anti-buckling steel plate. The side of the anti-buckling steel plate (16) close to the low-yield point steel plate (15) is conformed to the trapezoidal groove provided on the low-yield point steel plate (15). The horizontal length of the rectangular through hole on the low-yield point steel plate (15) is equal to the length of the rectangular through hole. The length of the straight section of the anti-buckling steel plate and the oblique straight section of the anti-buckling steel plate in the same horizontal direction is greater than that of the straight section of the anti-buckling steel plate and the oblique straight section of the anti-buckling steel plate. A plurality of bolt holes are provided on the side of the anti-buckling steel plate (16). The positions of the bolt holes correspond to the rectangular through holes of the low-yield point steel plate (15). The diameter of the bolt holes is equal to the height of the rectangular through holes of the low-yield point steel plate (15). The low-yield point steel plate (15) and the anti-buckling steel plate (16) are connected by bolts. After the connection, the distance between the end of the straight section of the low-yield point steel plate and the two strip steel plates (17) satisfies the ultimate compression of the low-yield point steel plate (15).

2. The double-stage energy-absorbing concrete-filled steel tube column-wide flat beam node structure according to claim 1 is characterized in that: According to the connection method between the low-yield point steel plate (15) and the anti-buckling steel plate (16), the ultimate length of the anti-buckling steel plate (16) can be calculated. The ultimate length of the anti-buckling steel plate (16) is The calculation formula is as follows: Where, is the distance between the end of the straight section of the low yield point steel plate and the left strip steel plate, is the horizontal length of the straight section of the low yield point steel plate, is the distance between the end of the straight section of the low yield point steel plate and the right strip steel plate, is the strain of the low yield point steel plate.

3. The double-stage energy-absorbing concrete-filled steel tube column-wide flat beam node structure according to claim 1 is characterized in that: The steel tube concrete column (1) comprises a core concrete (18), a steel tube (19), two first end plates (20) and a plurality of PVC tubes (21), wherein the core concrete (18) is poured into the steel tube (19), the first end plate (20) has a convex cross-section and comprises a fixed section and a middle section, the fixed sections of the two first end plates (20) are respectively welded to the steel tube (19) near the side of the prefabricated wide flat beam (2), and the plurality of PVC tubes (21) are installed on the remaining two sides of the steel tube (19) after concrete pouring.

4. The double-stage energy-absorbing concrete-filled steel tube column-wide flat beam node structure according to claim 3 is characterized in that: Bolt holes are respectively provided on the middle section of the first end plate (20) and on both sides of the fixed section. The width of the fixed section of the first end plate (20) is greater than the width of the steel pipe (19).

5. The double-stage energy-absorbing concrete-filled steel tube column-wide flat beam node structure according to claim 4, characterized in that: The prefabricated wide flat beam (2) comprises steel bars (22), concrete (23), an I-beam (25), a plurality of shear nails (24), a second end plate (26), stiffening ribs (27) and a third end plate (28). The steel bars (22) and the concrete (23) constitute the beam body of the prefabricated wide flat beam (2). The I-beam (25) is embedded in the end of the prefabricated wide flat beam (2). The plurality of shear nails (24) are arranged on the upper and lower flanges of the I-beam (25). The end of the I-beam (25) is welded to the second end plate (26). The other side of the second end plate (26) is welded with longitudinal bars in the horizontal direction and the stiffening ribs (27) in the vertical direction. The other side of the longitudinal bars and the stiffening ribs (27) is welded to the third end plate (28).

6. The double-stage energy-absorbing concrete-filled steel tube column-wide flat beam node structure according to claim 5, characterized in that: The second end plate (26) has a rectangular cross-section, and its cross-section size is equal to that of the prefabricated wide flat beam.

7. The double-stage energy-absorbing concrete-filled steel tube column-wide flat beam node structure according to claim 5, characterized in that: The third end plate (28) further includes a steel plate (29), the cross section of the steel plate (29) is rectangular, bolt holes are provided on both sides of the steel plate (29), the rectangular side of the first ear plate (12) on the third end plate (28) is centrally welded to the steel plate (29), and the side of the steel plate (29) to which the first ear plate (12) is not welded is welded to the longitudinal reinforcement and the stiffening rib (27).

8. The double-stage energy-absorbing concrete-filled steel tube column-wide flat beam node structure according to claim 7, characterized in that: Two metal energy dissipation devices are bolted side by side in parallel between the first end plate (20) of the steel tube concrete column (1) and the third end plate (28) of the prefabricated wide flat beam (2), and the strip steel plates (17) on the two side sides of the low yield point steel plate (15) of the metal energy dissipation device are bolted to the fixed section of the first end plate (20) on one side and bolted to the steel plate (29) of the third end plate (28) on the other side.

9. The double-stage energy-absorbing concrete-filled steel tube column-wide flat beam node structure according to claim 7, characterized in that: The rectangular sides of the two first ear plates (12) of the friction energy dissipation device are fixedly connected to the middle section of the first end plate (20) by bolts, and the steel block (14) is a rectangular steel block with bolt holes opened on the steel block (14). The second ear plate (13) is bolted to the rectangular side of the first ear plate (12) on the third end plate (28) through the steel block (14).

10. A construction method for a double-stage energy-absorbing concrete-filled steel tube column-wide flat beam node structure according to claim 1, characterized in that: The construction method is achieved by the following steps: Step 1: Making steel tube concrete columns (1) and prefabricated wide flat beams (2); Step 2: Connect the friction energy dissipation device, and bolt the friction energy dissipation device to the steel tube concrete column (1) and the prefabricated wide flat beam (2); Step 3: Apply pre-tightening force to the friction energy dissipation device installed in step 2, and then connect the metal energy dissipation device with the steel tube concrete column (1) and the prefabricated wide flat beam (2) by bolts.

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