A column base structure of an embedded steel column

Abstract

The utility model relates to the technical field of building steel columns, and specifically discloses a column foot structure of an embedded steel column, including a steel column body, a bottom plate fixedly connected to the bottom of the steel column body, and an anchor bolt pre-buried in the lower foundation. The bottom plate is provided with a connection hole at the position corresponding to the anchor bolt, and the top of the anchor bolt passes through the connection hole, and the anchor bolt and the bottom plate are fixedly connected by a nut; the steel column body is a steel pipe column, and the steel pipe column includes an above-ground section and an underground section. The underground section is surrounded by a rigid reinforcement shell, and a rigid constraint core is inserted into the interior of the underground section. The outer surface of the constraint core fits the inner surface of the underground section, and the top elevations of the reinforcement shell and the constraint core are both ±0.000 meters. The technical solution provided by the utility model can solve the technical problem that the column foot structure of the prior art has no reinforcement effect on the bearing capacity of the embedded steel column, resulting in the bearing capacity of the embedded steel column failing to meet the design requirements of occasions with greater bearing capacity requirements.

Description

Technical Field

[0001] The utility model relates to the technical field of building steel columns, in particular to a column foot structure of an embedded steel column. Background Art

[0002] Embedded steel columns, also known as pre-buried steel columns, refer to steel structural columns whose bottoms are embedded in the concrete foundation in construction projects. The construction method of embedded steel columns mainly involves the following process: first, embed the connectors (such as anchor plates, anchor bolts, etc.) at the designed position, then pour the concrete foundation to form the lower foundation, and after the concrete of the lower foundation reaches a certain strength, the steel column is fixedly connected to the lower foundation through the above-mentioned embedded connectors, and then continue to pour the concrete foundation to form the upper foundation, so that the bottom structure of the steel column is embedded in the upper foundation.

[0003] In a steel building structure system using embedded steel columns, the column base structure is an important component connecting the embedded steel columns and the foundation. It is used to transmit the supporting reaction force of the embedded steel columns on the foundation and constrain the displacement of the embedded steel columns. It is an important factor in determining the bearing capacity of the embedded steel columns and even the entire structural system. The column base structure of the prior art includes a base plate welded to the bottom of the embedded steel column and an anchor bolt pre-buried in the lower foundation. The base plate is provided with a connection hole at the position corresponding to the anchor bolt. The top of the anchor bolt passes through the connection hole, and then the anchor bolt and the base plate are fixed by nuts to achieve the fixation of the embedded steel column and the lower foundation.

[0004] The above prior art still has the following problems when used in practice:

[0005] 1) In situations where the bearing capacity of the embedded steel columns is required to be relatively large, such as when there is a need for driving on the surface layer, the embedded steel columns in the basement need to have a relatively large bearing capacity. However, the column base structure of the prior art does not enhance the bearing capacity of the embedded steel columns, resulting in the bearing capacity of the embedded steel columns failing to meet the design requirements.

[0006] 2) If the embedded steel column adopts a steel pipe column, since the column base structure of the prior art has no restraint or protection on the column body of the embedded steel column, when the embedded steel column is subjected to bending moment, axial force and other forces, it is easy to cause bending deformation, axial compression or tensile deformation, resulting in a reduction in the service life of the embedded steel column and affecting the safety of the entire structural system. Utility Model Content

[0007] The utility model is intended to provide a column base structure for an embedded steel column to solve the technical problem that the column base structure in the prior art has no effect on reinforcing the bearing capacity of the embedded steel column, resulting in the bearing capacity of the embedded steel column failing to meet the design requirements for occasions with greater bearing capacity requirements.

[0008] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0009] A column base structure for an embedded steel column, comprising a steel column body, a base plate fixedly connected to the bottom of the steel column body, and anchor bolts pre-buried in a lower foundation, wherein the base plate is provided with connection holes at positions corresponding to the anchor bolts, the tops of the anchor bolts pass through the connection holes, and the anchor bolts and the base plate are fixedly connected by nuts; the steel column body is a steel pipe column, and the steel pipe column comprises an above-ground section and an underground section, the underground section is surrounded by a rigid reinforcing shell, a rigid constraint core is inserted into the interior of the underground section, the outer surface of the constraint core is in contact with the inner surface of the underground section, and the top elevations of the reinforcing shell and the constraint core are both ±0.000 meters.

[0010] The principle and beneficial effects of this program:

[0011] In actual application, nuts are used to fix the bottom plate at the bottom of the steel column body to the anchor bolts pre-buried in the lower foundation to achieve fixed connection between the steel column body and the foundation. At this time, the underground section of the steel pipe column is located in the basement, and the above-ground section of the steel pipe column is located above the surface layer. First, a rigid constraint core is inserted inside the underground section, and then a rigid reinforcement shell is wrapped around the underground section so that the top elevation of the constraint core and the reinforcement shell reaches ±0.000 meters, that is, the top of the constraint core and the reinforcement shell reaches the position of the surface layer.

[0012] 1. This scheme sets the part of the steel column body located in the basement as the underground section, and wraps the reinforced shell around the underground section, which can effectively improve the bearing capacity of the embedded steel column and meet the driving needs of the surface layer. Its working principle is mainly based on the following aspects: (1) Composite force principle: The external reinforced shell and the steel column body form a combined structure and participate in the force together, thereby improving the bearing capacity and stability of the embedded steel column. (2) Changing the cross-sectional characteristics: By wrapping the reinforced shell, the cross-sectional size of the steel column body is actually increased, the moment of inertia and section modulus of the section are increased, thereby improving the bending, shear and torsion resistance of the embedded steel column. This means that under the same load, the deformation of the embedded steel column is reduced and the bearing capacity is increased. (3) Improving seismic performance: Under the action of an earthquake, the external reinforced shell can improve the energy dissipation capacity and ductility of the column base structure, reduce the seismic response, and thus improve the seismic performance of the embedded steel column. The reinforced shell can absorb seismic energy to a certain extent and protect the internal steel column body from damage.

[0013] 2. This scheme adopts a steel pipe column as the steel column body, and inserts a constraint core into the underground section of the steel pipe column. When the steel pipe column is subjected to lateral loads or receives unevenly distributed vertical loads and generates bending moments, the constraint core whose outer surface fits the inner surface of the steel pipe column can effectively restrain the bending deformation of the steel pipe column, thereby reducing or even avoiding the bending deformation of the steel pipe column; when the steel pipe column is directly subjected to axial tension or pressure, it may cause axial tension or compression deformation, and the rigid constraint core located inside the steel pipe column can share the axial tension or pressure, protect the steel pipe column from excessive tension or compression, thereby reducing or even avoiding the axial tension or compression deformation of the steel pipe column; therefore, this scheme can restrain and protect the steel pipe column, reduce or even avoid bending deformation, axial compression or tension deformation of the steel pipe column, which is beneficial to prolonging the service life of the buried steel column and ensuring the safety of the entire structural system.

[0014] Preferably, as an improvement, the reinforced shell includes a concrete layer cast on top of the lower foundation and a steel cage embedded in the concrete layer, and the bottom of the steel cage extends out of the concrete layer and is embedded in the interior of the lower foundation.

[0015] Beneficial effects: This solution sets the reinforced shell to include a concrete layer cast on the top of the lower foundation and a steel cage embedded in the concrete layer, that is, the reinforced shell is a reinforced concrete structure, which can provide excellent compressive resistance for the underground section of the steel column body, while the steel column body has excellent tensile resistance. This combined structure makes full use of the mechanical advantages of the two materials and can effectively enhance the bearing capacity and stability of the embedded steel column.

[0016] In addition, in this scheme, the bottom of the steel cage is extended out of the concrete layer and embedded in the lower foundation, which can improve the stability of the column base structure when it is subjected to axial force and torque, thereby improving the seismic performance of the embedded steel column and ensuring that the embedded steel column meets the seismic requirements. Specifically: (1) In this scheme, the fixed connection between the column base structure and the lower foundation is rigid connection. When the column base structure rigidly connected to the lower foundation is subjected to a torsional force, part of the force will drive the column base structure to have a tendency to rotate. At this time, the bottom structure of the steel cage embedded in the lower foundation blocks the rotation of the column base structure, thereby improving the torque resistance of the column base structure. (2) Compared with the previous method of anchoring the column base structure only with anchor bolts, the bottom structure of the steel cage embedded in the lower foundation in this scheme expands the effective area of ​​the column base structure when it is subjected to axial pressure and tension, thereby improving the upper limit of the column base structure's ability to withstand axial force.

[0017] Preferably, as an improvement, the steel cage includes a plurality of vertically arranged column longitudinal bars and a plurality of horizontally arranged column stirrups, the column longitudinal bars are arranged around the underground section, and the column stirrups are fixedly connected to the column longitudinal bars.

[0018] Beneficial effects: This solution sets the steel cage to include a number of vertically arranged column longitudinal bars and a number of horizontally arranged column stirrups. The bottom of the column longitudinal bars is embedded in the lower foundation, and part of the column stirrups is also embedded in the lower foundation. When the column base structure just connected to the lower foundation is subjected to a twisting force, part of the force will drive the column base structure to have a tendency to rotate. At this time, the bottom of the column longitudinal bars embedded in the lower foundation blocks the rotation of the column base structure, thereby improving the anti-torque performance of the column base structure. The part of the column stirrups embedded in the lower foundation expands the effective area of ​​the column base structure when it is subjected to axial pressure and tension, thereby increasing the upper limit of the axial force that the column base structure can withstand. In addition, this solution sets the column longitudinal bars around the underground section, which can improve the balance of the reinforcing effect of the reinforced shell on the steel column body, and the column stirrups are fixedly connected to the column longitudinal bars, which is convenient for pouring the concrete layer, avoiding displacement of the column stirrups during the pouring of the concrete layer, and ensuring the construction effect of the reinforced shell.

[0019] Preferably, as an improvement, the column stirrups include inner stirrups and outer stirrups arranged in sequence from the inside to the outside, and the inner stirrups and the outer stirrups are connected end to end to form a closed stirrup ring to surround the underground section.

[0020] Beneficial effect: This scheme arranges the column stirrups to include inner stirrups and outer stirrups arranged in sequence from the inside to the outside, and arranges the inner stirrups and the outer stirrups to be connected end to end, forming two layers of closed stirrup rings to surround the underground section, which can effectively improve the comprehensive performance of the reinforced outer shell, not only enhance the safety of the reinforced outer shell, but also improve the durability of the reinforced outer shell. Specifically, it manifests itself in the following aspects: (1) Improving shear bearing capacity: The inner and outer layers of stirrups can effectively constrain the concrete layer and improve the shear strength of the concrete layer, especially when subjected to lateral shear forces such as wind loads and earthquakes. It can significantly improve the overall shear bearing capacity and stability of the reinforced shell; (2) Enhancing torsional performance: The inner and outer layers of closed stirrup rings formed by the inner and outer stirrups can effectively constrain the core of the concrete layer and improve the torsional stiffness and torsional bearing capacity of the column base structure, which is crucial for resisting torsional loads such as wind torsion and torsional deformation caused by seismic waves; (3) Improving stress distribution: The inner and outer stirrups can evenly distribute the stress caused by external forces and reduce stress concentration, especially in the interface area where the concrete layer and the steel column body are combined, effectively preventing the concrete layer from cracking and improving the integrity and durability of the column base structure.

[0021] Preferably, as an improvement, the constraining core is a constraining core formed by poured concrete.

[0022] Beneficial effects: This solution sets the constraint core to be a constraint core formed by poured concrete. On the one hand, it can ensure that the outer surface of the constraint core fits with the inner surface of the underground section, so that when the steel column body is subjected to lateral loads or receives unevenly distributed vertical loads and generates bending moments, it can effectively restrain the steel column body, reduce or even avoid the bending deformation of the steel column body, and extend the service life of the steel column body; on the other hand, the constraint core formed by poured concrete can also meet the rigidity requirements, thereby sharing the axial tension or pressure for the steel column body, protecting the steel pipe column from excessive tension or compression, reducing or even avoiding the axial tension or compression deformation of the steel pipe column, and further extending the service life of the steel column body.

[0023] Preferably, as an improvement, a plurality of bolts are fixedly connected to the outer wall of the underground section, and the small diameter ends of the bolts are connected to the underground section.

[0024] Beneficial effects: This solution fixes the connecting bolts on the outer wall of the underground section, and connects the small diameter end of the bolt to the underground section, so that the large diameter end of the bolt is embedded in the concrete layer, which can effectively improve the bonding tightness between the overall steel column body and the concrete layer, thereby enhancing the shear and bending resistance of the column base structure.

[0025] Preferably, as an improvement, a filling layer is provided between the base plate and the lower foundation, and the filling layer is a filling layer formed by poured concrete.

[0026] Beneficial effects: This solution pours a filling layer between the bottom plate and the lower foundation, and fills the gap between the bottom plate and the lower foundation through the filling layer, so that the bottom plate and the lower foundation can form an integral mechanical connection unit, thereby significantly enhancing the connection strength and stability between the column base structure and the lower foundation, ensuring the shear and pull-out resistance of the column base structure, and preventing the column base structure from slipping or pulling out relative to the lower foundation under load. In addition, after pouring the filling layer between the bottom plate and the lower foundation to form a continuous structure, dynamic loads such as earthquakes can be effectively transmitted and distributed through the filling layer, reducing the vibration of the column base structure and improving the seismic performance of the column base structure.

[0027] Preferably, as an improvement, a plurality of exhaust holes are provided on the bottom plate, and the exhaust holes are arranged around the underground section; a through hole is provided in the middle of the bottom plate, and the center of the through hole coincides with the horizontal projection of the center of the web.

[0028] Beneficial effects: During the pouring of the filling layer between the base plate and the lower foundation, the mixture of cement slurry and aggregate will produce bubbles. If these bubbles are enclosed in the concrete of the filling layer, they will affect the strength and durability of the filling layer. This solution sets a number of exhaust holes on the base plate to provide an escape path for these bubbles, which can effectively remove the bubbles inside the concrete during the pouring process, which is beneficial to reduce the porosity and prevent the formation of large voids or bubble strings inside the concrete of the filling layer. Exhausting through the exhaust holes can make the concrete of the filling layer more compact during the solidification process, improve the integrity and bearing capacity of the filling layer, and reduce stress concentration and potential structural defects caused by internal voids. In addition, the exhaust holes can discharge bubbles to avoid bubbles from remaining in the contact area between the base plate and the filling layer, ensure the effective bonding area between the base plate and the filling layer, thereby ensuring the reliability of the connection between the base plate and the filling layer, preventing possible peeling or cracks in the future, and improving the durability of the column base structure.

[0029] Preferably, as an improvement, T-shaped stiffening ribs are fixedly connected to the outer wall of the underground section, and the T-shaped stiffening ribs include horizontal stiffening ribs and vertical stiffening ribs, and the top of the horizontal stiffening ribs is flush with the top of the upper foundation.

[0030] Beneficial effects: This solution fixes and connects T-shaped stiffeners including horizontal stiffeners and vertical stiffeners on the outer wall of the underground section, which can significantly enhance the local stability of the steel column body, reduce the buckling risk caused by the excessively high slenderness ratio of the steel column body, and improve the overall stability of the embedded steel column. Specifically, the vertical stiffeners help to improve the bending stiffness of the steel column body, while the horizontal stiffeners mainly enhance the shear resistance of the steel column body. The two work together to enable the steel column body to maintain good mechanical properties when subjected to complex loads, thereby helping to improve the bearing capacity of the embedded steel column.

[0031] In addition, this solution sets the top of the horizontal stiffening rib to be flush with the top of the upper foundation, which can optimize the connection between the steel column body and the upper foundation, improve the strength and rigidity of the connection, and ensure the effective transfer of load. And the top of the horizontal stiffening rib is flush with the top of the upper foundation, which can also avoid the formation of a cavity between the steel column body and the upper foundation, thereby preventing the accumulation of air or moisture, reducing the corrosion risk of the steel column body, and improving the durability of the embedded steel column.

[0032] Preferably, as an improvement, the steel cage further comprises a plurality of horizontally arranged dense stirrups, which are connected end to end to form a closed stirrup ring to surround the T-shaped stiffening rib, and the distance between two adjacent dense stirrups is smaller than the distance between two adjacent column stirrups.

[0033] Beneficial effects: The area near the top of the foundation is a shear concentration area. This solution sets denser stirrups around the T-shaped stiffening ribs, that is, denser stirrups are set near the top of the upper foundation, and the density of the denser stirrups is greater than the density of the column stirrups, which can effectively constrain the concrete layer in this area, significantly improve the shear strength of the reinforced shell, and prevent shear failure. And the setting of denser stirrups with higher density can enhance the rigidity of the entire reinforced shell, so that the entire embedded steel column can maintain better stability when subjected to lateral loads, such as wind loads or seismic loads. In addition, the setting of denser stirrups can encrypt the stirrups near the top of the upper foundation, thereby improving the stress distribution in this area, reducing stress concentration, avoiding early cracks in the concrete layer, and improving the durability of the column foot structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is a schematic diagram of the overall structure of Example 1 of the utility model.

[0035] Figure 2 for Figure 1 A top view of (foundation not shown).

[0036] Figure 3 It is a top view of the steel column body and the base plate in Example 1 of the utility model.

[0037] Figure 4 For the utility model embodiment 2 and Figure 2 Schematic diagram of the structure from the same perspective.

[0038] Figure 5 For the utility model embodiment 2 and Figure 3 Schematic diagram of the structure from the same perspective.

[0039] Figure 6 This is a top view of the steel column and base plate in Example 3 of the utility model (the bolts are not shown). DETAILED DESCRIPTION

[0040] The following is further described in detail through specific implementation methods:

[0041] The figure marks in the drawings of the specification include: lower foundation 101, upper foundation 102, steel column body 1, underground section 10, base plate 2, anchor bolts 3, nuts 4, filling layer 5, studs 6, T-shaped stiffening ribs 7, horizontal stiffening ribs 71, vertical stiffening ribs 72, reinforced shell 8, concrete layer 81, steel cage 82, column longitudinal reinforcement 821, column stirrups 822, inner stirrups 8221, outer stirrups 8222, dense stirrups 823, restraining core 9, exhaust holes 11, and through holes 12.

[0042] Example 1

[0043] A column foot structure of an embedded steel column, as shown in the attached Figure 1As shown, it includes a steel column body 1, a bottom plate 2 welded and fixed to the bottom of the steel column body 1, and an anchor bolt 3 pre-buried in the lower foundation 101. The bottom plate 2 has a connection hole at a position corresponding to the anchor bolt 3, and the top of the anchor bolt 3 passes through the connection hole. By tightening the nut 4 threadedly connected to the anchor bolt 3 and located at the upper and lower positions of the bottom plate 2, the nuts 4 located at the upper and lower positions of the bottom plate 2 cooperate to clamp and fix the bottom plate 2, thereby realizing a fixed connection between the bottom plate 2 and the anchor bolt 3, thereby realizing a fixed connection between the steel column body 1 and the lower foundation 101. A filling layer 5 is provided between the bottom plate 2 and the lower foundation 101, and the filling layer 5 is a filling layer 5 formed by poured concrete.

[0044] The steel column body 1 is a steel pipe column. In this embodiment, the steel pipe column is a square steel pipe column. The steel pipe column includes an above-ground section (not shown in the figure) and an underground section 10. A plurality of bolts 6 are welded and fixed to the outer wall of the underground section 10, and the small diameter end of the bolt 6 is connected to the underground section 10. Figure 3 As shown, the bolts 6 are evenly arranged in one circle around the underground section 10, and are evenly arranged in several circles in the vertical direction. T-shaped stiffening ribs 7 are also welded and fixed on the outer wall of the underground section 10. The T-shaped stiffening ribs 7 include horizontal stiffening ribs 71 arranged horizontally and vertical stiffening ribs 72 arranged vertically. The middle position of the bottom of the horizontal stiffening rib 71 is welded and fixed to the top of the vertical stiffening rib 72. The top of the horizontal stiffening rib 71 is flush with the top of the upper foundation 102.

[0045] The underground section 10 is surrounded by a rigid reinforcement shell 8, and a rigid constraint core 9 is inserted into the interior of the underground section 10. The top elevations of the reinforcement shell 8 and the constraint core 9 are both ±0.000 meters. The outer surface of the constraint core 9 fits the inner surface of the underground section 10. Specifically, the constraint core 9 is formed by pouring concrete.

[0046] The reinforced shell 8 includes a concrete layer 81 cast on the top of the lower foundation 101 and a steel cage 82 embedded in the concrete layer 81, and the bottom of the steel cage 82 extends out of the concrete layer 81 and is embedded in the lower foundation 101. In this embodiment, the outer contour of the concrete layer 81 is also square, and the center of the concrete layer 81 coincides with the horizontal projection of the center of the square steel pipe column.

[0047] The steel cage 82 includes a plurality of vertically arranged column longitudinal bars 821 and a plurality of horizontally arranged column stirrups 822. The column longitudinal bars 821 are evenly arranged in a square shape around the underground section 10. The column stirrups 822 are fixedly connected to the column longitudinal bars 821 at equal intervals in the vertical direction. Specifically, the column stirrups 822 are tied and fixed to the column longitudinal bars 821 by connecting members such as steel wires. Figure 2As shown, the column stirrups 822 include inner stirrups 8221 and outer stirrups 8222 arranged in sequence from the inside to the outside, and the inner stirrups 8221 and the outer stirrups 8222 are connected end to end to form a closed stirrup ring to surround the underground section 10. In this embodiment, the inner stirrups 8221 are octagonal, the outer stirrups 8222 are rectangular, and the joints of the inner stirrups 8221 and the outer stirrups 8222 are staggered.

[0048] like Figure 1 As shown, the steel cage 82 also includes a number of horizontally arranged dense stirrups 823, which are also tied and fixed to the column longitudinal reinforcement 821 by connecting members such as steel wires. The dense stirrups 823 are connected end to end to form a closed stirrup ring, which surrounds the T-shaped stiffening rib 7, that is, the dense stirrups 823 are arranged below the top of the upper foundation 102 and close to the top of the upper foundation 102. The dense stirrups 823 are arranged at equal intervals in the vertical direction, and the distance between two adjacent dense stirrups 823 is smaller than the distance between two adjacent column stirrups 822.

[0049] The specific implementation process is as follows:

[0050] (1) Construction of lower foundation 101: Build a formwork at the designed position, fix the anchor bolts 3 and the bottom of the steel cage 82 inside the formwork, and then pour concrete inside the formwork to form the lower foundation 101. At this time, the anchor bolts 3 and the bottom of the steel cage 82 are pre-buried inside the lower foundation 101, and the top of the anchor bolts 3 and the top of the bottom of the steel cage 82 are exposed from the lower foundation 101.

[0051] (2) Assembly of the steel column body 1: Studs 6 and T-shaped stiffening ribs 7 are welded on the outer surface of the underground section 10 of the steel pipe column, so that the studs 6 are evenly distributed in the direction around the underground section 10 and along the length direction of the underground section 10, the horizontal stiffening ribs 71 and the vertical stiffening ribs 72 of the T-shaped stiffening ribs 7 are perpendicular to each other, and the top of the horizontal stiffening rib 71 is located at the corresponding position of the top of the lower foundation 101; then, the bottom plate 2 is welded to the bottom of the steel pipe column, so that the horizontal projections of the center of the steel pipe column and the center of the bottom plate 2 coincide.

[0052] (3) Installation of the steel column body 1: After the concrete of the lower foundation 101 reaches a certain strength, a nut 4 is threaded onto the anchor bolt 3, and the assembled steel column body 1 is hoisted onto the lower foundation 101 by a lifting device, so that the top of the anchor bolt 3 passes through the corresponding connection hole on the bottom plate 2, and then two nuts 4 are connected on the anchor bolt 3, and the nuts 4 located at the upper and lower positions of the bottom plate 2 are tightened so that the bottom plate 2 is clamped by the nuts 4, thereby achieving a fixed connection between the bottom plate 2 and the anchor bolt 3, thereby achieving a fixed connection between the steel column body 1 and the lower foundation 101, and completing the installation of the steel column body 1.

[0053] (4) Construction of filling layer 5: Concrete is poured in the gap between the bottom plate 2 and the lower foundation 101 to form a filling layer 5, and the bottom plate 2 and the lower foundation 101 are tightly connected through the filling layer 5.

[0054] (5) Construction of the restraining core 9: Concrete is poured into the interior of the steel pipe column to form the restraining core 9, and the top elevation of the restraining core 9 is ensured to reach ±0.000 meters.

[0055] (6) Construction of the reinforced outer shell 8: The upper part of the steel cage 82 is welded at the portion of the bottom of the steel cage 82 where the lower foundation 101 is exposed. Specifically, the upper column longitudinal reinforcements 821 are welded one by one to the bottom column longitudinal reinforcements 821, and the upper column stirrups 822 are tied and fixed to the upper column longitudinal reinforcements 821 to form the upper steel cage 82; then, a formwork is built around the upper steel cage 82, and concrete is poured in the formwork to form a concrete layer 81 until the top elevation of the concrete layer 81 reaches ±0.000 meters, thereby completing the construction of the reinforced outer shell 8.

[0056] (7) Construction of upper foundation 102: Build a formwork at the designed position and pour concrete into the formwork to form the upper foundation 102, so that the bottom of the reinforced shell 8 is buried in the upper foundation 102 and the top of the upper foundation 102 is flush with the top of the horizontal stiffening rib 71.

[0057] Example 2

[0058] A column foot structure of an embedded steel column, as shown in the attached Figure 4 and Figure 5 As shown, the difference between it and Example 1 is that the steel pipe column is a circular steel pipe column, the bottom plate 2 is also a circular bottom plate 2, and the center of the bottom plate 2 is located on the axis of the steel pipe column. In this embodiment, the column longitudinal reinforcement 821 is evenly arranged in a circular shape around the underground section 10 of the steel pipe column, and the center of the circle formed by the column longitudinal reinforcement 821 is located on the axis of the steel pipe column; the inner layer stirrup 8221 is circular, and the inner layer stirrup 8221 is coaxially arranged with the steel pipe column; the outer layer stirrup 8222 is square, and the center of the outer layer stirrup 8222 is located on the axis of the steel pipe column.

[0059] Example 3

[0060] A column foot structure of an embedded steel column, as shown in the attached Figure 6As shown, the difference from Example 1 is that: a plurality of through exhaust holes 11 are opened on the bottom plate 2, and the exhaust holes 11 are evenly arranged around the underground section 10. In this embodiment, an exhaust hole 11 is arranged at a position corresponding to the midpoint of each side of the underground section 10 to ensure that the gas generated during the pouring of the filling layer 5 can be evenly discharged through the exhaust hole 11. A through hole 12 is opened in the middle of the bottom plate 2, and the center of the through hole 12 coincides with the horizontal projection of the center of the web. The through hole 12 can not only play a role in exhaust, but also can be used for center positioning when assembling the bottom plate 2 and the steel column body 1, so as to improve the convenience and accuracy of assembly.

[0061] The above is only an embodiment of the utility model, and the common knowledge such as the known specific technical solutions and / or characteristics in the solution is not described in detail here. It should be pointed out that for those skilled in the art, without departing from the technical solution of the utility model, several deformations and improvements can be made, which should also be regarded as the protection scope of the utility model, and these will not affect the effect of the implementation of the utility model and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A column foot structure of an embedded steel column, comprising a steel column body, a bottom plate fixedly connected to the bottom of the steel column body, and an anchor bolt pre-buried in the lower foundation, wherein a connection hole is opened at the position of the bottom plate corresponding to the anchor bolt, the top of the anchor bolt passes through the connection hole, and the anchor bolt and the bottom plate are fixedly connected by a nut; characterized in that: The steel column body is a steel pipe column, which includes an above-ground section and an underground section. The underground section is covered with a rigid reinforced outer shell, and a rigid constraint core is inserted into the interior of the underground section. The outer surface of the constraint core is in contact with the inner surface of the underground section, and the top elevations of the reinforced outer shell and the constraint core are both ±0.000 meters.

2. The column base structure of an embedded steel column according to claim 1, characterized in that: The reinforced shell comprises a concrete layer cast on the top of the lower foundation and a steel cage embedded in the concrete layer, wherein the bottom of the steel cage extends out of the concrete layer and is embedded in the interior of the lower foundation.

3. The column base structure of an embedded steel column according to claim 2, characterized in that: The steel cage comprises a plurality of vertically arranged column longitudinal bars and a plurality of horizontally arranged column stirrups, wherein the column longitudinal bars are arranged around the underground section, and the column stirrups are fixedly connected to the column longitudinal bars.

4. The column base structure of an embedded steel column according to claim 3, characterized in that: The column stirrups include inner stirrups and outer stirrups which are arranged in sequence from the inside to the outside. The inner stirrups and the outer stirrups are connected end to end to form a closed stirrup ring to surround the underground section.

5. The column base structure of an embedded steel column according to claim 1, characterized in that: The constraining core is a constraining core formed by poured concrete.

6. The column base structure of an embedded steel column according to claim 1, characterized in that: A plurality of bolts are fixedly connected to the outer wall of the underground section, and the small diameter ends of the bolts are connected to the underground section.

7. The column base structure of an embedded steel column according to claim 1, characterized in that: A filling layer is arranged between the bottom plate and the lower foundation, and the filling layer is formed by poured concrete.

8. The column base structure of an embedded steel column according to claim 7, characterized in that: The bottom plate is provided with a plurality of exhaust holes, which are arranged around the underground section; a through hole is provided in the middle of the bottom plate, and the center of the through hole coincides with the horizontal projection of the center of the web.

9. The column base structure of an embedded steel column according to claim 2 or 3, characterized in that: The outer wall of the underground section is fixedly connected with a T-shaped stiffening rib, the T-shaped stiffening rib comprises a horizontal stiffening rib and a vertical stiffening rib, and the top of the horizontal stiffening rib is flush with the top of the upper foundation.

10. The column base structure of an embedded steel column according to claim 9, characterized in that: The steel cage also includes a plurality of horizontally arranged dense stirrups, which are connected end to end to form a closed stirrup ring to surround the T-shaped stiffening rib, and the distance between two adjacent dense stirrups is smaller than the distance between two adjacent column stirrups.

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