Efficient anti-seismic concrete reinforcement composite reinforcing structure and construction method

Abstract

The invention relates to the technical field of building structure engineering, and discloses an efficient anti-seismic concrete reinforcement composite reinforcing structure and a construction method.The efficient anti-seismic concrete reinforcement composite reinforcing structure comprises an original floor slab, an original beam and a composite reinforcing assembly with the synergistic effect; the composite reinforcing assembly comprises a three-dimensional anchoring structure, a rigid force transmission frame structure, an energy dissipation and shock absorption structure and a constraint protection structure. The three-dimensional anchoring structure is composed of a connecting rib penetrating through an original floor slab, extending plates symmetrically extending on the two sides of the lower portion of the connecting rib, fixing claws linearly arrayed on the two sides of the extending plates and a U-shaped steel plate wrapping an original beam, and the fixing claws and the U-shaped steel plate are welded to form a multi-directional stress mechanical meshing structure. In the three-dimensional anchoring structure, firstly, the three-dimensional anchoring structure forms multidirectional mechanical occlusion through welding of the connecting ribs, the extension plates, the fixing claws and the U-shaped steel plates, the anchoring integrity of an original floor slab and an original beam is enhanced, the defect of single-point stress of a traditional anchoring mode is overcome, and the stability of the structure is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of building structure engineering, and particularly relates to a high-efficiency anti-seismic concrete steel bar composite reinforcing structure and a construction method. BACKGROUND

[0002] In the field of building structure engineering, with the increase of the service life of existing buildings and the continuous improvement of the anti-seismic design standard, the reinforcement and reconstruction demand of concrete structures is increasingly prominent, especially in the earthquake-prone areas, the anti-seismic performance of key components such as concrete beams and floors directly relates to the overall safety of the building, and the traditional structure is prone to deformation, cracking or even collapse due to the problems such as insufficient bearing capacity and weak connecting nodes when in long-term use or subjected to earthquake action, therefore, the development of high-efficiency and reliable anti-seismic reinforcing technology has become an important task to improve the safety performance of existing buildings.

[0003] In the existing reinforcing method, the cross-section increasing method, the steel bonding method and the carbon fiber cloth reinforcing method have obvious limitations in practical application: the traditional anchoring mode mainly relies on single node stress, cannot form a multi-directional collaborative mechanical interlocking structure, the dispersion of the force transmission path is insufficient, anchoring failure is easily caused by local stress concentration, and even cracks are caused at the connecting position of the original structure and the reinforcing component, thereby weakening the overall reinforcing effect. SUMMARY

[0004] In order to make up for the above shortcomings, the present application provides a high-efficiency anti-seismic concrete steel bar composite reinforcing structure and a construction method, aiming at improving the problem that the traditional anchoring mode mainly relies on single node stress and cannot form a multi-directional collaborative mechanical interlocking structure.

[0005] In order to achieve the above-mentioned purpose, the present application adopts the following technical scheme: a high-efficiency anti-seismic concrete steel bar composite reinforcing structure, comprising an original floor, an original beam and a collaborative composite reinforcing assembly, the bottom of the original floor is fixedly connected with the original beam, the composite reinforcing assembly comprises a three-dimensional anchoring structure, a rigid force transmission frame structure, an energy dissipation and shock absorption structure and a constraint protection structure; the three-dimensional anchoring structure is composed of a connecting rib penetrating through the original floor, extension plates symmetrically extended on both sides of the lower part of the connecting rib, fixed claws linearly arrayed on both sides of the extension plates and a U-shaped steel plate wrapped around the original beam, the fixed claws and the U-shaped steel plate are welded to form a multi-directional stress mechanical interlocking structure; the rigid force transmission frame structure is fixed with a web plate through a chemical bolt implanted in the original beam and a fastener, the web plate is welded with a middle plate, the middle plate is butted with an I-shaped beam through a long strip-shaped positioning groove and is locked through a connecting piece, a C-shaped welding strip is arranged around the connecting position to realize rigid sealing connection; the energy dissipation and shock absorption structure is formed by the I-shaped beam coated with a graphene coating and the C-shaped welding strip, and can absorb seismic energy through plastic deformation of the welding strip; the constraint protection structure is fixed with a top surface pad plate of the original floor through a connecting rib top fastener and a U-shaped steel plate adhered to the original beam, and forms full-wrapping constraint for the original beam to limit concrete crushing and peeling.

[0006] Preferably, the connecting rod is a long bolt, the top end of which is fastened to the base plate through a hexagon washer nut, and the bottom end of which is welded to the U-shaped steel plate with a welding area not less than 60% of the surface area of the extension plate.

[0007] Preferably, the fixing claw is a triangular cross-section steel claw, the tip of which is embedded in the pre-fabricated pit on the surface of the U-shaped steel plate and is welded and fixed, forming a mechanical locking and welding force double fixing structure.

[0008] Preferably, the implantation depth of the chemical bolt is 1 / 3-1 / 2 of the original beam cross-section height, the modified epoxy resin anchoring glue is used, the single bolt uplift bearing capacity is not less than 80kN, and the distance between adjacent chemical bolts is 300mm.

[0009] Preferably, the fastener is a hexagon washer nut, the welding seam between the web plate and the middle plate is continuous full welding, and the welding seam thickness is not less than 1 / 2 of the web plate thickness.

[0010] Preferably, the width of the long strip type positioning groove is 2-5mm wider than the flange width of the girder, the length penetrates the whole length of the middle plate, the connecting piece is composed of a bolt and a hexagon washer nut, and the locking torque is 40-60N・m.

[0011] Preferably, the thickness of the C-shaped welding strip is 8-12mm, the welding leg height is 8mm, the wrapping range covers all the joints of the girder and the middle plate connection, and after welding, the ultrasonic flaw detection reaches the first-class qualified standard.

[0012] Preferably, the thickness of the graphene coating on the surface of the girder is 20-50μm, which is coated by gas phase deposition process, and the surface of the girder is treated by sandblasting before coating to Sa2.5 level.

[0013] Preferably, the U-shaped steel plate and the original beam surface are filled with elastic damping material, the damping ratio of which is not less than 0.15, the coating thickness is 2-3mm and there is no bubble.

[0014] A construction method of a high-efficiency anti-seismic concrete steel bar composite reinforcement structure, comprising the following steps:

[0015] S1, original structure pretreatment, removing the loose concrete on the surface of the original beam and cleaning to expose the main reinforcement metal luster, pre-setting the installation hole matched with the connecting rod on the original floor, the hole diameter is 2mm larger than the diameter of the connecting rod;

[0016] S2, installing the anchoring system, drilling holes and implanting chemical bolts at the pre-set position of the original beam, using modified epoxy resin anchoring glue to solidify and the solidification time is not less than 24 hours, then fixing the web plate to the front surface of the original beam through the fastener and applying 80N・m torque, and then welding the middle plate and the web plate into one body;

[0017] S3, assemble the beam, insert the I-beam coated with a graphene coating into the middle plate, align the positioning hole with the positioning groove, lock with the connecting piece, weld the C-shaped welding strip at the connecting part with a welding leg height of 8mm, and form a sealed force transmission joint;

[0018] S4, install the steel plate system, tightly wrap the U-shaped steel plate around the original beam surface and temporarily fix it, weld the extension plate on both sides of the connecting rib, weld the fixing claw on both sides of the extension plate at an interval of 150mm, and weld the fixing claw and the U-shaped steel plate firmly;

[0019] S5, overall connection and acceptance, pass the connecting rib through the original floor mounting hole, rotate the gasket plate to 50N.m by the fastener at the top, perform ultrasonic flaw detection on all welds and achieve the I-class qualified standard, and then brush the epoxy zinc-rich primer with a dry film thickness of not less than 60μm.

[0020] The present application has the following beneficial effects:

[0021] 1. In the present application, firstly, the three-dimensional anchoring structure is formed by welding the connecting rib, the extension plate, the fixing claw and the U-shaped steel plate to form a multi-directional mechanical interlocking, which enhances the anchoring integrity of the original floor and the original beam, and avoids the single-point stress defect of the traditional anchoring method; the rigid force transmission frame structure is connected rigidly by chemical bolts, webs, middle plates and beams, and sealed force transmission by C-shaped welding strips, which builds a clear and stable load transmission path, solving the problem of "strong component and weak connection"; the energy dissipation structure uses the cooperation of the I-beam and the C-shaped welding strip to absorb seismic energy through plastic deformation of the welding strip, reducing the impact load borne by the original beam; the restraint protection structure is fully wrapped by the U-shaped steel plate, effectively limiting the crushing and peeling of the original beam concrete, and improving the overall damage resistance of the structure.

[0022] 2. In the present application, the connecting rib adopts long bolts and optimizes the welding area, the fixing claw adopts triangular cross-section steel claw and is embedded in the U-shaped steel plate pit, which doubles the connection strength of the anchoring structure; the implantation depth of the chemical bolt, the type and spacing of the anchoring glue ensure the uplift bearing capacity and stability of the anchoring system; the type of fastener, the requirement of weld and the size of positioning groove improve the connection reliability of the rigid force transmission frame; the thickness of the C-shaped welding strip, the welding standard and the graphene coating treatment of the beam surface enhance the durability and energy dissipation efficiency of the energy dissipation structure; the elastic damping material filled between the U-shaped steel plate and the original beam further improves the seismic energy dissipation capacity; the step-by-step specification of the construction method ensures the accuracy of the structure installation and the acceptance quality, making the overall reinforcement effect more stable and controllable. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 It is a first perspective structure schematic diagram of a high-efficiency anti-seismic concrete steel bar composite reinforcement structure according to the present application;

[0024] Figure 2 A high-efficiency anti-seismic concrete steel bar composite reinforcing structure extension plate and steel plate connecting structure schematic diagram is provided for the present application;

[0025] Figure 3 A second perspective structure schematic diagram of a high-efficiency anti-seismic concrete steel bar composite reinforcing structure is provided for the present application;

[0026] Figure 4 A high-efficiency anti-seismic concrete steel bar composite reinforcing structure Figure 3 A magnified structure schematic diagram of the middle A;

[0027] Figure 5 A third perspective structure schematic diagram of a high-efficiency anti-seismic concrete steel bar composite reinforcing structure is provided for the present application.

[0028] Legend:

[0029] 1, original floor; 2, original beam; 3, chemical bolt; 4, fastener; 5, web; 6, middle plate; 7, positioning groove; 8, beam; 9, positioning hole; 10, connecting piece; 11, welding strip; 12, steel plate; 13, connecting bar; 14, pad; 15, extension plate; 16, fixing claw. DETAILED DESCRIPTION

[0030] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of protection of the present application.

[0031] Embodiment one, refer to Figures 1-5The utility model provides a kind of high-efficiency anti-seismic concrete reinforcing bar composite reinforcing structure, including original floor 1, original beam 2 and synergic composite reinforcing component, original floor 1 bottom is fixedly connected with original beam 2, composite reinforcing component includes three-dimensional anchoring structure, rigid force transmission frame structure, energy dissipation and shock absorption structure and restraint protection structure;Three-dimensional anchoring structure is by the connecting rib 13 of through original floor 1, the extension plate 15 of its lower part two sides symmetry extension, the fixed claw 16 of linear array in the extension plate 15 two sides and the U-shaped steel plate 12 of wrapping original beam 2 are constituted, and fixed claw 16 is welded with U-shaped steel plate 12 and forms multi-directional stress mechanical interlock structure;Rigid force transmission frame structure is fixed web 5 by fastener 4 through chemical bolt 3 implanted in original beam 2, after web 5 and middle plate 6 are welded, middle plate 6 is butted with I-shaped beam 8 through long strip type positioning groove 7 and is locked by connecting piece 10, and C-shaped welding band 11 is arranged around the junction and realizes rigid sealing connection;Energy dissipation and shock absorption structure is formed by I-shaped beam 8 with C-shaped welding band 11 cooperation with the surface coating graphene coating, and can be absorbed seismic energy by welding band plastic deformation;Restraint protection structure is fixed by the U-shaped steel plate 12 of sticking original beam 2 through connecting rib 13 top fastener 4 and original floor 1 top surface backing plate 14, forms full wrapping restraint to original beam 2 to limit concrete crushing and peeling, after connecting rib 13 of three-dimensional anchoring structure is through original floor 1, the fixed claw 16 of lower extension plate 15 two sides is welded with the U-shaped steel plate 12 of wrapping original beam 2 and forms multi-directional mechanical interlock, and rigid force transmission frame structure is welded by web 5 and middle plate 6 fixed by chemical bolt 3, and then is butt joint with beam 8 by positioning groove 7 and cooperates C-shaped welding band 11 and transmits force, and chemical bolt 3 adopts modified epoxy resin anchoring glue solidification, and web is fixed on original beam front by fastener and is applied 80N with torque, becomes the basis that rigid force transmission frame is connected with original beam, provides starting point for load transmission, ensures the firm connection of web and original beam, builds stable force transmission basis for rigid force transmission frame, avoids the force transmission interruption due to connection loosening, enhances the reliability of overall structure force transmission, and beam 8 and C-shaped welding band 11 of energy dissipation and shock absorption structure absorb energy by welding band plastic deformation, and the U-shaped steel plate 12 of restraint protection structure is fixed by connecting rib 13 top fastener 4 and backing plate 14 and wraps original beam 2, and the overall anti-seismic capacity of original floor 1 and original beam 2 is significantly improved by the synergy of four structures.

[0032] Embodiment two, refer to Figures 1-5On the basis of embodiment one, the connecting rib 13 is a long bolt, the top end is fastened with the hexagon washer nut 4 and the washer plate 14, and the bottom end is extended to the welding area of the U-shaped steel plate 12, which is 60% of the surface area of the extended plate 15. Such a connection mode makes the force transmission of the anchorage node more efficient and the overall stability stronger. The fixed claw 16 is a triangular cross-section steel claw, the tip of which is embedded in the pre-prepared pit on the surface of the U-shaped steel plate 12 and is welded and fixed, forming a mechanical locking and welding force double fixation, which greatly improves the connection strength of the three-dimensional anchoring structure. The chemical bolt 3 is implanted according to 1 / 3 of the cross-sectional height of the original beam 2, and the modified epoxy resin anchoring glue is used, and the single bolt uplift bearing capacity is 80kN, and the adjacent spacing is 300mm. Such a setting ensures that the anchoring system can stably bear the load, and the overall anchoring effect is more reliable. The fastener 4 is a hexagonal washer nut, the welding seam between the web plate 5 and the middle plate 6 is continuous full welding, and the welding seam thickness is 1 / 2 of the thickness of the web plate 5, which makes the overall rigidity of the force transmission frame structure better and the force transmission more reliable. The width of the long strip type positioning groove 7 is 3mm wider than the flange width of the beam 8, and the length penetrates the full length of the middle plate 6, the connecting piece 10 is composed of a bolt and a hexagonal washer nut, and the locking torque is 50N·m. Such a beam 8 and middle plate 6 butt joint is more accurate, and the force transmission is more stable. The C-shaped welding strip 11 is 10mm thick, the welding leg height is 8mm, and it wraps all the joints of the beam 8 and the middle plate 6, and after welding, it reaches the first-class qualified standard through ultrasonic detection, which makes the shear performance of the connecting part stronger and the energy dissipation effect better. The surface of the beam 8 is coated with a graphene coating with a thickness of 30μm, which is coated using a vapor deposition process. The surface of the beam 8 is sandblasted to Sa2.5 level before coating, which significantly improves the corrosion resistance of the beam 8 and prolongs its service life. The U-shaped steel plate 12 and the surface of the original beam 2 are filled with elastic damping material with a damping ratio of 0.15 and a coating thickness of 2.5mm without bubbles, which can further dissipate seismic energy and improve the overall seismic effect.

[0033] Embodiment three, refer to Figures 1-5 A construction method of a high-efficiency anti-seismic concrete steel bar composite reinforcement structure, comprising the following steps:

[0034] S1, original structure pretreatment, remove the loose concrete on the surface of the original beam and clean it to expose the main reinforcement metal luster, and pre-set installation holes matching the connecting rib on the original floor, the hole diameter is 2mm larger than the diameter of the connecting rib;

[0035] S2, install the anchoring system, drill holes and implant chemical bolts at the preset position of the original beam, use modified epoxy resin anchoring glue to solidify, and after solidification for not less than 24 hours, fix the web plate to the front of the original beam through the fastener and apply 80N·m torque, then weld the middle plate and the web plate into one body;

[0036] S3, assemble the girder, insert the I-shaped girder coated with a graphene coating into the middle plate, align the positioning holes and positioning grooves, lock with a connecting piece, weld a C-shaped welding strip at the connection and the welding leg height is 8mm, and form a sealed force transmission joint;

[0037] S4, install the steel plate system, tightly wrap the U-shaped steel plate around the original beam surface and temporarily fix it, weld extension plates on both sides of the lower part of the connecting rib, and weld fixed claws on both sides of the extension plates at an interval of 150mm, so that the fixed claws are firmly welded with the U-shaped steel plate;

[0038] S5, overall connection and acceptance, pass the connecting rib through the original floor mounting hole, and tighten the gasket plate to 50N・m at the top end through the fastener, and after the ultrasonic flaw detection of all welds reaches the I-level qualified standard, brush the epoxy zinc-rich primer and the dry film thickness is not less than 60μm.

[0039] The construction method pretreats the original structure according to the steps, installs the anchoring system, assembles the girder 8, installs the steel plate system and accepts it, each link operates according to the specification, ensures the precise cooperation of each component, and finally guarantees the construction quality of the reinforced structure and stable seismic performance.

[0040] Working principle: In the three-dimensional anchoring structure, the connecting rib 13 penetrates the original floor 1, the extension plates 15 on both sides of the lower part are welded with the U-shaped steel plate 12 wrapped around the original beam 2 through the linear array of fixed claws 16 on both sides, forming a multi-directional stress mechanical interlocking structure, which transmits the load of the original floor 1 to the original beam 2 and enhances the overall anchoring stability; the rigid force transmission frame structure fixes the web plate 5 through the chemical bolts 3 implanted in the original beam 2, the web plate 5 is welded with the middle plate 6, and then the middle plate 6 is butted with the I-shaped girder 8 through the long strip-shaped positioning groove 7, locked by the connecting piece 10 and sealed and connected with the C-shaped welding strip 11, forming a rigid force transmission path from the girder 8 to the middle plate 6 to the original beam 2, ensuring efficient transmission of force.

[0041] In the energy dissipation and seismic reduction structure, the graphene coating on the surface of the I-shaped girder 8 improves the durability, and it forms a deformable energy dissipation unit with the C-shaped welding strip 11, which absorbs energy and reduces the impact on the original beam 2 when subjected to earthquake action; in the restraint and protection structure, the U-shaped steel plate 12 wrapped around the original beam 2 is fixed with the gasket plate 14 on the top surface of the original floor 1 through the fastener 4 at the top end of the connecting rib 13, forming a full-wrapped restraint of the original beam 2, limiting the concrete from breaking and peeling off, and the four structures work together to achieve efficient seismic reinforcement effect.

[0042] Finally, it should be noted that the above only describes the preferred embodiments of the present application and is not intended to limit the present application. Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art will appreciate that the technical solutions described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalent features, and any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A highly efficient earthquake-resistant concrete-steel composite reinforcement structure, comprising an original floor slab (1), an original beam (2) and synergistic composite reinforcement components, characterized in that: The bottom of the original floor slab (1) is fixedly connected to the original beam (2), and the composite reinforcement assembly includes a three-dimensional anchoring structure, a rigid force transmission frame structure, an energy dissipation and shock absorption structure, and a restraint protection structure; The three-dimensional anchoring structure is composed of a connecting rib (13) passing through the original floor slab (1), an extension plate (15) extending symmetrically on both sides of the lower portion thereof, a linear array of fixing claws (16) on both sides of the extension plate (15), and a U-shaped steel plate (12) wrapping the original beam (2), wherein the fixing claws (16) and the U-shaped steel plate (12) are welded to form a mechanical interlocking structure subjected to multi-directional forces; The rigid force transmission frame structure is fixed to the web (5) via a fastener (4) through a chemical bolt (3) implanted in the original beam (2). After the web (5) is welded to the middle plate (6), the middle plate (6) is butted against the I-shaped added beam (8) via a long strip positioning groove (7) and locked via a connector (10). A C-shaped welding strip (11) is provided around the connection to achieve a rigid sealed connection. The energy dissipation and shock absorption structure is formed by an I-shaped beam (8) with a graphene coating on its surface and a C-shaped welding strip (11), and can absorb earthquake energy through plastic deformation of the welding strip; The restraining protection structure is composed of a U-shaped steel plate (12) that fits the original beam (2) and is fixed to the top surface pad (14) of the original floor slab (1) through the top fasteners (4) of the connecting ribs (13), forming a full-wrapped restraint on the original beam (2) to limit the crushing and spalling of concrete.

2. The high-efficiency earthquake-resistant concrete-steel composite reinforcement structure according to claim 1, characterized in that: The connecting rib (13) is a long bolt, the top end of which is fastened to the backing plate (14) via a hexagonal nut (4).

3. The high-efficiency earthquake-resistant concrete-steel composite reinforcement structure according to claim 1, characterized in that: The fixing claw (16) is a triangular cross-section steel claw, the tip of which is embedded in a prefabricated recess on the surface of the U-shaped steel plate (12) and fixed by welding, forming a dual fixing structure of mechanical locking and welding force.

4. The high-efficiency earthquake-resistant concrete-steel composite reinforcement structure according to claim 1, characterized in that: The chemical bolt (3) adopts modified epoxy resin anchoring glue, and the pull-out bearing capacity of a single bolt is not less than 80kN.

5. The high-efficiency earthquake-resistant concrete-steel composite reinforcement structure according to claim 1, characterized in that: The fastener (4) is a hexagonal nut with a washer, and the welding seam between the web (5) and the middle plate (6) is a continuous full weld.

6. The high-efficiency earthquake-resistant concrete-steel composite reinforcement structure according to claim 1, characterized in that: The length of the long strip positioning groove (7) runs through the entire length of the middle plate (6), and the connecting piece (10) is composed of a bolt and a hexagonal nut with a washer.

7. The high-efficiency earthquake-resistant concrete-steel composite reinforcement structure according to claim 1, characterized in that: The wrapping range of the C-shaped welding strip (11) covers all the joints at the connection between the added beam (8) and the middle plate (6), and after welding, the ultrasonic flaw detection reaches the first-level qualified standard.

8. The high-efficiency earthquake-resistant concrete-steel composite reinforcement structure according to claim 1, characterized in that: The graphene coating on the surface of the added beam (8) is coated by a vapor deposition process, and before coating, the surface of the added beam (8) is sandblasted and derusted to Sa2.5 level.

9. The high-efficiency earthquake-resistant concrete-steel composite reinforcement structure according to claim 1, characterized in that: The space between the U-shaped steel plate (12) and the surface of the original beam (2) is filled with elastic damping material, the damping ratio of the material is not less than 0.15 and there are no bubbles.

10. A construction method for a highly efficient earthquake-resistant concrete-steel composite reinforced structure, characterized by: The following steps are involved: S1, pre-treatment of the original structure: remove the loose concrete on the surface of the original beam and clean it until the metallic luster of the main reinforcement is exposed. Pre-set installation holes that match the connecting reinforcement in the original floor slab, with the hole diameter 2mm larger than the diameter of the connecting reinforcement; S2: Install the anchoring system. Drill holes and insert chemical bolts at the preset locations on the original beam. Use modified epoxy resin anchoring adhesive and cure it for at least 24 hours. Fasten the web to the front of the original beam with fasteners and apply a torque of 80 N·m. Then weld the center plate and web together. S3, assemble the beam. Insert the I-shaped beam coated with graphene into the middle plate. Align the positioning holes with the positioning grooves and tighten them with connectors. Weld a C-shaped welding strip at the joint with a welding foot height of 8 mm to form a sealed force transmission node. S4, install the steel plate system, tighten the U-shaped steel plate to the original beam surface and temporarily fix it, weld extension plates on both sides of the lower part of the connecting reinforcement, and weld fixing claws on both sides of the extension plate at a spacing of 150mm, so that the fixing claws are firmly welded to the U-shaped steel plate; S5, overall connection and acceptance: pass the connecting reinforcement through the original floor installation hole, tighten the pad to 50N·m with fasteners at the top, conduct ultrasonic testing on all welds and meet the Class I qualification standard, and then apply epoxy zinc-rich primer with a dry film thickness of not less than 60μm.

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