Method for constructing permanent steel stand column by reverse construction method
By grinding the surface of the steel columns and installing annular plates and anchor bolts, a tight connection system is formed, which solves the problem of unreliable connection between steel columns and concrete, improves the stability and durability of the structure, and avoids local damage and corrosion.
Patent Information
- Application Number
- CN202510995805.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-18
- Publication Date
- 2025-09-12
AI Technical Summary
In the existing technology, the connection between steel columns and concrete is unreliable, resulting in insufficient structural stability and safety. In addition, the quality of concrete pouring is difficult to ensure and defects are prone to occur, affecting the safety of long-term use.
By grinding the surface of the steel columns, setting annular plates and anchor bolts, and inserting stress-bearing steel bars, a tight connection system is formed. The beams, plates and the lower sections of the steel columns are combined, and finally the outer cladding is cast on the periphery to form an integral structure.
It significantly improves the connection strength and coordinated load-bearing capacity between steel columns and concrete, optimizes the overall load-bearing performance of the structure, prevents local damage and corrosion, and enhances the stability and durability of the structure.
Smart Images
Figure CN120625802A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of steel column construction, in particular to a reverse construction method for permanent steel column construction. Background Art
[0002] During the reverse construction process of a building project, the construction quality of permanent steel columns plays a key role in the stability and safety of the entire structure. However, during the current construction process of encapsulating steel columns into permanent supporting columns, the connection reliability between the steel columns and the outer concrete is clearly insufficient.
[0003] In the existing technology, steel columns and concrete are connected by simple dowel bars or anchors. This connection method is prone to stress concentration when subjected to force, resulting in local damage to the connection parts and unable to ensure close coordination between the two, thus affecting the stability and safety of the entire structure.
[0004] In actual construction, steel columns usually exist as independent components, and the connection between them and the beams and plates is not tight enough, resulting in the force transmission between the various parts not being smooth when the structure is subjected to stress, which easily leads to stress concentration and damage at the connection parts.
[0005] In addition, when the quality of concrete pouring is difficult to guarantee, defects such as honeycombs, rough surfaces, and holes are likely to appear during concrete pouring, which will not only reduce the strength and durability of the concrete itself, but also further weaken the reliability of the connection between the steel columns and the concrete, making the structure face safety hazards during long-term use. Summary of the Invention
[0006] The purpose of the present invention is to provide a reverse construction method for permanent steel columns, aiming to solve the problem of unreliable connection between steel columns and concrete in the prior art.
[0007] The present invention is achieved by a reverse construction method for permanent steel columns, comprising the following construction steps: 1) Carry out excavation to expose the steel columns and grind the surfaces of the steel columns; 2) The steel column has a lower section and an upper section formed above the lower section. Two annular plates are arranged in the lower section with an interval between them. The annular plates are arranged around the circumference of the lower section, and a plate interval is formed between the two annular plates. 3) A plurality of stress-bearing steel bars are passed through the two annular plates, and the plurality of stress-bearing steel bars are arranged around the circumference of the lower section at intervals. The stress-bearing steel bars have lower bars passing through the plate intervals; the stress-bearing steel bars extend upward through the annular plates and have upper bars surrounding the outer circumference of the upper section; 4) Arrange the beam reinforcement and the slab reinforcement, and connect the beam reinforcement and the slab reinforcement to the lower reinforcement as a whole; support the beam formwork and the slab formwork, and surround the beam formwork to form a beam cavity. The lower reinforcement and two annular plates are placed in the beam cavity, and the slab formwork surrounds the slab cavity; 5) Pour concrete into the beam cavity, and after the concrete solidifies, form a beam body, and the lower reinforcement and two annular plates are wrapped in the beam body; Pour concrete into the plate cavity, and after the concrete solidifies, form a plate body, and the plate body, beam body and lower section of the steel column are combined into one; 6) A column formwork is supported on the periphery of the steel column. The column formwork surrounds the periphery of the upper section and forms a column cavity. Concrete is poured in the column cavity. After the concrete solidifies, an outer layer is formed. The outer layer is combined with the steel column to form an integrated structural column.
[0008] Furthermore, in the construction step 1), the surface of the steel column is polished to remove impurities on the surface of the steel column, so that the surface cleaning section of the steel column meets the set requirements.
[0009] Furthermore, in the construction step 2), a plurality of anchor bolts are welded on the outer periphery of the lower segment, and the plurality of anchor bolts are arranged at intervals along the circumference and axial direction of the lower segment. The inner ends of the anchor bolts are welded on the outer periphery of the lower segment, and the outer ends of the anchor bolts are arranged to extend outward away from the lower segment.
[0010] Furthermore, in the construction step 2), the bottom of the annular plate is connected to a plurality of support plates that support the annular plate from bottom to top, the plurality of support plates are arranged around the circumference of the lower section at intervals, and the support plates are connected to the lower section by welding.
[0011] Furthermore, in the construction step 2), the top of the support plate has a horizontal surface, which is welded to the bottom of the annular plate and is integrated with the annular plate; the inner side of the support plate has a longitudinal surface, which is welded to the outer periphery of the lower section and is integrated with the lower section; the outer side of the annular plate has an inclined surface, which is arranged inwardly along the direction from top to bottom of the annular plate.
[0012] Furthermore, the horizontal plane and the longitudinal plane intersect to form an intersection, and the intersection is chamfered. The intersection is hollowed out and spaced apart from the annular plate and the lower section.
[0013] Furthermore, in the construction step 3), the plurality of stressed steel bars are enclosed to form a square shape, and the lower bars are in contact with the sides of the anchor bolts and are welded and fixed to the anchor bolts as a whole.
[0014] Furthermore, in the construction step 2), the annular plate is provided with a plurality of through holes which are arranged vertically and horizontally, and the plurality of through holes are arranged around the circumference of the annular plate at intervals; in the construction step 3), the stressed steel bars respectively pass through the through holes of the two annular plates to form the lower ribs in the plate interval and the upper ribs above the annular plate.
[0015] Furthermore, in the construction step 4), the end of the beam reinforcement has an overlapping portion, which overlaps the top of the annular plate, presses against the annular plate from top to bottom, and is welded and fixed to the annular plate as a whole.
[0016] Furthermore, in the construction step 2), the inner end of the anchor bolt has an inner end head, the inner end head has an inward end surface facing the lower section, the inward end surface is connected to the lower section, and the outer periphery of the inward end surface is welded to the lower section; The middle portion of the anchor bolt has a middle section, which is curved to enclose a middle hole that passes through the bolt vertically; the outer end of the anchor bolt has an outer end bar, which is flat and horizontally arranged, and has a plurality of through holes that pass through the bolt vertically; In the construction step 3), the stressed steel bar passes through the middle hole, and the middle section encloses and abuts the outer periphery of the stressed steel bar and is welded and fixed to the stressed steel bar; in the construction step 5), after pouring concrete in the beam cavity, the concrete passes through the through hole, is integrated with the interior of the anchor bolt, and wraps the entire anchor bolt.
[0017] Compared with the existing technology, the reverse construction method of permanent steel column provided by the present invention has the following technical advantages: 1) By grinding the surface of the steel column (step 1), the surface oxide layer, impurities and uneven parts are removed, which significantly improves the bond strength between the steel column and the subsequent poured concrete, laying the foundation for the reliability of the subsequent connection.
[0018] 2) By setting two annular plates spaced apart from each other in the lower section of the steel column (step 2), and arranging them around the circumference of the steel column, a stable anchoring point is provided for the stressed steel bars; by passing the stressed steel bars through the annular plates and extending them to the upper section (step 3), a tight connection system of "annular plates-stressed steel bars-steel column" is formed. This ensures that the stressed steel bars and the steel column have both mechanical anchoring and bonding after being wrapped in concrete, thereby enhancing the coordinated load-bearing capacity of the two.
[0019] 3) In step 5, by pouring concrete in the beam cavity and the slab cavity, the formed beam body and slab body are tightly integrated with the lower section of the steel column. This not only improves the connection strength between the steel column and the concrete, but also optimizes the overall stress performance of the structure and avoids local damage caused by weak connections.
[0020] 4) In step 6, an outer layer is formed by pouring concrete around the outer periphery of the upper section of the steel column, further combining the steel column and concrete into an integral structure; the outer layer not only enhances the bearing capacity of the steel column, but also provides additional durability protection, effectively preventing corrosion and fatigue damage of the steel column during long-term use. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Figure 1 This is a schematic flow chart of the reverse construction method for permanent steel columns provided by the present invention; Figure 2 It is a structural schematic diagram of the steel column provided by the present invention; Figure 3 It is a structural schematic diagram of the stress-bearing steel bars and beam steel bars provided by the present invention; Figure 4 is a simplified schematic diagram of the support plate provided by the present invention; Figure 5 is a cross-sectional schematic diagram of the anchor bolt provided by the present invention; In the figure: steel column 100, lower section 101, upper section 102, annular plate 103, stress-bearing steel bars 104, lower bars 105, upper bars 106, beam steel bars 107, lap joint 108; Support plate 200, horizontal surface 201, longitudinal surface 202, inclined surface 203, intersection 204; Anchor bolt 300 , inner end head 301 , inward end surface 302 , middle section 303 , middle hole 304 , outer end strip 305 , through hole 306 . DETAILED DESCRIPTION
[0022] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.
[0023] The implementation of the present invention is described in detail below with reference to specific embodiments.
[0024] The same or similar numbers in the drawings of this embodiment correspond to the same or similar parts; in the description of the present invention, it should be understood that if the terms "up", "down", "left", "right", etc. indicate directions or positional relationships, they are based on the directions or positional relationships shown in the drawings. This is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, the terms describing the positional relationship in the drawings are only used for illustrative purposes and cannot be understood as limiting the present invention. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.
[0025] Reference Figure 1-5 The figure shows a preferred embodiment of the present invention.
[0026] The reverse construction method for permanent steel columns includes the following construction steps: 1) Perform excavation to expose the steel column 100 and polish the surface of the steel column 100; 2) The steel column 100 comprises a lower section 101 and an upper section 102 formed above the lower section 101. Two annular plates 103 are arranged in the lower section 101 with an interval therebetween. The annular plates 103 are arranged around the circumference of the lower section 101, with a plate interval between the two annular plates 103. 3) Multiple stress-bearing steel bars 104 are passed through the two annular plates 103. The multiple stress-bearing steel bars 104 are arranged around the circumference of the lower section 101 at intervals. The stress-bearing steel bars 104 have lower ribs 105 that pass through the plate intervals. The stress-bearing steel bars 104 extend upward through the annular plates 103 and have upper ribs 106 that surround the outer circumference of the upper section 102. 4) Arrange the beam reinforcement 107 and the slab reinforcement, and connect the beam reinforcement 107 and the slab reinforcement with the lower reinforcement 105 as a whole; support the beam formwork and the slab formwork, and surround the beam formwork to form a beam cavity. Place the lower reinforcement 105 and the two annular plates 103 in the beam cavity, and surround the slab formwork to form a slab cavity; 5) Pour concrete into the beam cavity. After the concrete solidifies, the beam body is formed. The lower reinforcement 105 and the two annular plates 103 are wrapped in the beam body. Pour concrete into the plate cavity. After the concrete solidifies, the plate body is formed. The plate body, the beam body and the lower section 101 of the steel column 100 are combined into one. 6) A column formwork is supported on the periphery of the steel column 100. The column formwork surrounds the periphery of the upper section 102. The column formwork surrounds and forms a column cavity. Concrete is poured in the column cavity. After the concrete solidifies, an outer layer is formed. The outer layer is combined with the steel column 100 to form an integrated structural column.
[0027] The above-mentioned reverse construction method for permanent steel columns 100 has the following technical advantages: 1) By polishing the surface of the steel column 100 (step 1), the surface oxide layer, impurities and uneven parts are removed, which significantly improves the bonding strength between the steel column 100 and the subsequent poured concrete, laying the foundation for the reliability of the subsequent connection.
[0028] 2) By providing two annular plates 103 spaced apart from each other on the lower section 101 of the steel column 100 (step 2), and arranging them circumferentially around the steel column 100, a stable anchoring point is provided for the stressed steel bars 104; by passing the stressed steel bars 104 through the annular plates 103 and extending them to the upper section 102 (step 3), a tight connection system of "annular plates 103 - stressed steel bars 104 - steel column 100" is formed, so that the stressed steel bars 104 and the steel column 100 have both a mechanical anchoring effect and a bonding effect after being wrapped with concrete, thereby enhancing the coordinated force-bearing capacity of the two.
[0029] 3) In step 5, by pouring concrete in the beam cavity and the plate cavity, the formed beam body and the plate body are tightly integrated with the lower section 101 of the steel column 100. This not only improves the connection strength between the steel column 100 and the concrete, but also optimizes the overall stress performance of the structure and avoids local damage caused by weak connection.
[0030] 4) In step 6, an outer layer is formed by pouring concrete around the outer periphery of the upper section 102 of the steel column 100, further combining the steel column 100 and the concrete into an integral structure; the outer layer not only enhances the bearing capacity of the steel column 100, but also provides additional durability protection, effectively preventing corrosion and fatigue damage of the steel column 100 during long-term use.
[0031] In this embodiment, in construction step 1), the surface of the steel column 100 is polished to remove impurities on the surface of the steel column 100 so that the surface cleaning section of the steel column 100 meets the set requirements.
[0032] In this way, the bonding strength between the subsequent concrete and the steel column 100 can be effectively improved, ensuring a close connection between the two and laying a good foundation for subsequent construction steps.
[0033] In this embodiment, in construction step 2), multiple anchor bolts 300 are welded to the outer periphery of the lower segment 101. The multiple anchor bolts 300 are arranged at intervals along the circumference and axial direction of the lower segment 101. The inner ends of the anchor bolts 300 are welded to the outer periphery of the lower segment 101, and the outer ends of the anchor bolts 300 are arranged to extend outward away from the lower segment 101.
[0034] By providing the anchor bolts 300 , the anchoring points between the steel column 100 and the concrete are increased, the reliability of the connection is improved, the relative slippage between the steel column 100 and the concrete is effectively prevented, and the problem of unreliable connection between the steel column 100 and the concrete is solved.
[0035] In this embodiment, in construction step 2), the bottom of the annular plate 103 is connected to multiple support plates 200 that support the annular plate 103 from bottom to top. The multiple support plates 200 are arranged around the circumference of the lower section 101 at intervals, and the support plates 200 are connected to the lower section 101 by welding.
[0036] The setting of the support plate 200 provides stable support for the annular plate 103, ensuring the position accuracy of the annular plate 103 during the construction process, thereby ensuring the installation accuracy of the subsequent stressed steel bars 104, and indirectly improving the connection strength between the steel column 100 and the concrete.
[0037] In this embodiment, in construction step 2), the top of the support plate 200 has a horizontal surface 201, which is welded to the bottom of the annular plate 103 and is integrated with the annular plate 103; the inner side of the support plate 200 has a longitudinal surface 202, which is welded to the outer periphery of the lower section 101 and is integrated with the lower section 101; the outer side of the annular plate 103 has an inclined surface 203, which is arranged to be inclined inward along the direction from top to bottom of the annular plate 103.
[0038] This forms a stable connection system between the support plate 200, the annular plate 103 and the lower section 101, thereby enhancing the stability of the entire structure and further improving the connection reliability between the steel column 100 and the concrete.
[0039] In this embodiment, the horizontal surface 201 and the longitudinal surface 202 intersect to form an intersection 204 . The intersection 204 is chamfered and hollowed out, and is spaced apart from the annular plate 103 and the lower section 101 .
[0040] The use of chamfering and hollow design helps to reduce stress concentration and improve the durability of the structure. At the same time, it is also conducive to the pouring and filling of concrete, ensuring that the concrete can fully wrap each component and enhance the reliability of the connection.
[0041] In this embodiment, in construction step 3), a plurality of stressed steel bars 104 are enclosed to form a square shape, and the lower bars 105 are in contact with the sides of the anchor bolts 300 and are welded and fixed to the anchor bolts 300 as a whole.
[0042] Welding the stressed steel bars 104 to the anchor bolts 300 further strengthens the connection strength between the steel column 100 and the concrete, so that the stressed steel bars 104 can effectively transfer the load of the concrete to the steel column 100, thereby improving the integrity of the structure.
[0043] In this embodiment, in construction step 2), a plurality of through holes are provided in the annular plate 103 and are arranged in an upward and downward manner, and the plurality of through holes are arranged in a circumferential manner along the annular plate 103; in construction step 3), the stressed steel bars 104 respectively pass through the through holes of the two annular plates 103 to form lower ribs 105 in the plate interval and upper ribs 106 above the annular plates 103.
[0044] In this way, the stressed steel bars 104 can be evenly distributed throughout the structure, thereby improving the cooperative working ability between the concrete and the steel columns 100 and avoiding unreliable connection between the steel columns 100 and the concrete.
[0045] In this embodiment, in construction step 4), the end of the beam reinforcement 107 has a lap portion 108, which is overlapped on the top of the annular plate 103, pressed against the annular plate 103 from top to bottom, and welded to the annular plate 103 as a whole.
[0046] By welding and fixing the beam reinforcement 107 and the annular plate 103, the connection strength between the beam reinforcement 107 and the steel column 100 is enhanced, ensuring effective force transmission between the beam structure and the steel column 100 and improving the overall stability of the structure.
[0047] In this embodiment, in construction step 2), the inner end of the anchor bolt 300 has an inner end head 301, and the inner end head 301 has an inner end surface 302 facing the lower section 101. The inner end surface 302 is connected to the lower section 101, and the outer periphery of the inner end surface 302 is welded to the lower section 101. The anchor bolt 300 has a middle section 303 in the middle, which is curved to enclose a middle hole 304 extending vertically therethrough. The outer end of the anchor bolt 300 has an outer end bar 305, which is flat and horizontally arranged. The outer end bar 305 has a plurality of through holes 306 extending vertically therethrough. In construction step 3), the stressed steel bar 104 passes through the middle hole 304, and the middle section 303 surrounds and abuts the outer periphery of the stressed steel bar 104, and is welded and fixed to the stressed steel bar 104; in construction step 5), after concrete is poured in the beam cavity, the concrete passes through the through hole 306, is integrated with the interior of the anchor bolt 300, and wraps the entire anchor bolt 300.
[0048] By welding the anchor bolts 300 and the stressed steel bars 104 and wrapping them with concrete, a strong connection system is formed, which enables the steel column 100 and the concrete to work closely together, thereby achieving a reliable connection between the steel column 100 and the concrete.
[0049] Hereinafter, the technical solutions in the embodiments of the present invention will be described in detail, clearly and completely in combination with the embodiments of the present invention, so that the contents of the reverse construction method of permanent steel columns are easier to understand.
[0050] The reverse construction method for permanent steel columns includes the following construction steps: 1. Construction preparation Clean the surface of the steel column after excavation, and use grinding to remove impurities such as oil, rust, and dust to expose the metallic luster on the surface of the steel column and reach the cleanliness standard of Sa2.5 or above. For defects such as pits and damage on the surface of the steel column, fill them with welding and grind them smooth; weld anchor bolts on the outer periphery of the lower section of the steel column to increase the bonding strength with the subsequent concrete pouring.
[0051] 2. Ring plate setting An annular plate is welded to the lower section of the steel column. The annular plate is divided into two parts, which are arranged at the upper and lower parts of the lower section respectively. The annular plate is customized in the factory as a structure divided in half and welded on the steel column to form an integral annular plate, which serves as a connector between the steel column and the outer concrete. The annular plate is punched in the factory according to the drawings. When the two annular plates are installed, they are aligned by T-head positioning steel bars to facilitate the subsequent passage of stress-bearing steel bars. A support plate is provided below the annular plate and is arranged around the steel column. The support plate is welded to the steel column to better connect the annular plate and the steel column.
[0052] 3. Setting of stress reinforcement The stressed steel bars are passed through the pre-opened through holes in the upper and lower annular plates and fixed with anchor bolts by welding to form a stable steel bar skeleton.
[0053] 4. Tie up beam and slab reinforcement and support formwork Tie the beam reinforcement and slab reinforcement, and connect them with the lower reinforcement of the stressed reinforcement respectively; set up the beam formwork and slab formwork, the beam formwork surrounds to form a beam cavity, the lower reinforcement and two annular plates are placed in the beam cavity, and the slab formwork surrounds to form a slab cavity.
[0054] 5. Pouring beam and slab concrete Concrete is poured into the beam cavity and the slab cavity. After the concrete solidifies, the beam body and the slab body are formed, so that the slab body, the beam body and the lower section of the steel column are combined into one.
[0055] 6. Support and pouring of external column formwork A column formwork is supported on the periphery of the steel column, and the column formwork surrounds the periphery of the upper section of the steel column to form a column cavity; concrete is poured in the column cavity, and after the concrete solidifies, an outer layer is formed, which is combined with the steel column to form an integrated structural column.
[0056] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.
Claims
1. The reverse construction method of permanent steel columns is characterized by: The construction steps include: 1) Carry out excavation to expose the steel columns and grind the surfaces of the steel columns; 2) The steel column has a lower section and an upper section formed above the lower section. Two annular plates are arranged in the lower section with an interval between them. The annular plates are arranged around the circumference of the lower section, and a plate interval is formed between the two annular plates. 3) A plurality of stress-bearing steel bars are passed through the two annular plates, and the plurality of stress-bearing steel bars are arranged around the circumference of the lower section at intervals. The stress-bearing steel bars have lower bars passing through the plate intervals; the stress-bearing steel bars extend upward through the annular plates and have upper bars surrounding the outer circumference of the upper section; 4) Arrange the beam reinforcement and the slab reinforcement, and connect the beam reinforcement and the slab reinforcement to the lower reinforcement as a whole; support the beam formwork and the slab formwork, and surround the beam formwork to form a beam cavity. The lower reinforcement and two annular plates are placed in the beam cavity, and the slab formwork surrounds the slab cavity; 5) Pour concrete into the beam cavity, and after the concrete solidifies, form a beam body, and the lower reinforcement and two annular plates are wrapped in the beam body; Pour concrete into the plate cavity, and after the concrete solidifies, form a plate body, and the plate body, beam body and lower section of the steel column are combined into one; 6) A column formwork is supported on the periphery of the steel column. The column formwork surrounds the periphery of the upper section and forms a column cavity. Concrete is poured in the column cavity. After the concrete solidifies, an outer layer is formed. The outer layer is combined with the steel column to form an integrated structural column.
2. The reverse construction method for permanent steel columns according to claim 1, characterized in that: In the construction step 1), the surface of the steel column is polished to remove impurities on the surface of the steel column, so that the surface cleaning section of the steel column meets the set requirements.
3. The reverse construction method for permanent steel columns according to claim 1, characterized in that: In the construction step 2), a plurality of anchor bolts are welded to the outer periphery of the lower section. The plurality of anchor bolts are arranged at intervals along the circumference and axial direction of the lower section. The inner ends of the anchor bolts are welded to the outer periphery of the lower section, and the outer ends of the anchor bolts are arranged to extend outward away from the lower section.
4. The reverse construction method for permanent steel columns according to any one of claims 1 to 3, characterized in that: In the construction step 2), the bottom of the annular plate is connected to a plurality of support plates that support the annular plate from bottom to top. The plurality of support plates are arranged around the circumference of the lower section at intervals, and the support plates are connected to the lower section by welding.
5. The reverse construction method for permanent steel columns according to claim 4, characterized in that: In the construction step 2), the top of the support plate has a horizontal surface, which is welded to the bottom of the annular plate and integrated with the annular plate; the inner side of the support plate has a longitudinal surface, which is welded to the outer periphery of the lower section and integrated with the lower section; the outer side of the annular plate has an inclined surface, which is arranged inwardly along the direction from top to bottom of the annular plate.
6. The reverse construction method for permanent steel columns according to claim 5, characterized in that: The horizontal plane and the longitudinal plane intersect to form an intersection, and the intersection is chamfered. The intersection is hollowed out and spaced apart from the annular plate and the lower section.
7. The reverse construction method for permanent steel columns according to any one of claims 1 to 3, characterized in that: In the construction step 3), the plurality of stressed steel bars are enclosed to form a square shape, and the lower bars are in contact with the sides of the anchor bolts and are welded and fixed to the anchor bolts as a whole.
8. The reverse construction method for permanent steel columns according to any one of claims 1 to 3, characterized in that: In the construction step 2), the annular plate is provided with a plurality of through holes which are arranged vertically and horizontally, and the plurality of through holes are arranged circumferentially and spaced apart along the circumference of the annular plate; in the construction step 3), the stressed steel bars respectively pass through the through holes of the two annular plates to form the lower ribs in the plate interval and the upper ribs above the annular plates.
9. The reverse construction method for permanent steel columns according to any one of claims 1 to 3, characterized in that: In the construction step 4), the ends of the beam reinforcement bars have overlapping portions, which overlap the top of the annular plate, press against the annular plate from top to bottom, and are welded and fixed to the annular plate as a whole.
10. The reverse construction method for permanent steel columns according to claim 3, characterized in that: In the construction step 2), the inner end of the anchor bolt has an inner end head, the inner end head has an inward end surface facing the lower section, the inward end surface is connected to the lower section, and the outer periphery of the inward end surface is welded to the lower section; The middle portion of the anchor bolt has a middle section, which is curved to enclose a middle hole that passes through the bolt vertically; the outer end of the anchor bolt has an outer end bar, which is flat and horizontally arranged, and has a plurality of through holes that pass through the bolt vertically; In the construction step 3), the stressed steel bar passes through the middle hole, and the middle section encloses and abuts the outer periphery of the stressed steel bar and is welded and fixed to the stressed steel bar; in the construction step 5), after pouring concrete in the beam cavity, the concrete passes through the through hole, is integrated with the interior of the anchor bolt, and wraps the entire anchor bolt.