A kind of annular prestressed assembled external column foot and construction method

Abstract

The invention discloses a circumferential prestressed assembled outsourcing column foot and construction method, the structure includes a foundation, a steel column installed on the foundation and an outsourcing module, the steel column is provided with a pin outside; the outsourcing module includes four outsourcing column foot blocks, the four outsourcing column foot blocks are spliced ​​to each other in the middle to enclose a space for passing the steel column; the outsourcing column foot block is provided with a pin hole for inserting the pin; the four outsourcing column foot blocks are provided with prestressed channels connected in sequence, and the prestressed channels are provided with prestressed tendons, one end of the prestressed tendons is anchored at the internal interface, and the other end is passed through and anchored from the external interface; reserved steel bars are provided on the foundation, and a grouting sleeve connected to the reserved steel bars is provided at the lower end of the outsourcing column foot block; micro-expansion concrete is poured into the steel column, and cement slurry is poured between the steel column and the outsourcing module. The invention has the characteristics of convenient processing and installation, reliable force transmission, good mechanical properties, energy saving and emission reduction, etc., and provides guidance for the design and construction of assembled outsourcing column foot.

Description

Technical Field

[0001] The invention relates to the technical field of building structure engineering, and in particular to a circumferential prestressed assembled externally wrapped column foot and a construction method. Background Art

[0002] The column base is an important node connecting the upper main structure and the foundation. It can effectively fix the column body and effectively transfer the axial force, shear force and bending moment at the lower end of the column to the lower structure or foundation, allowing the upper structure and the lower structure to work together.

[0003] The existing Chinese utility model patent with application number CN215670534U discloses an outsourced column base structure, including: a base plate; a steel column, the steel column is fixedly connected to the base plate; a stiffening plate, the stiffening plate is located above the base plate, the stiffening plate includes an outer portion and an embedded portion, the outer portion is located on the outer side of the steel column, the embedded portion is located inside the steel column, the embedded portion is provided with a through hole, the through hole connects the upper and lower sides of the embedded portion, the outer portion is provided with a groove, the groove connects the upper and lower sides of the outer portion; a concrete structure, the concrete structure includes a steel cage, a first concrete layer and a second concrete layer, the first concrete layer is cast on the outer periphery of the steel column, the steel cage surrounds the outer periphery of the steel column, the base plate and the stiffening plate and is embedded in the first concrete layer, the second concrete layer is cast inside the steel column, and the stiffening plate is embedded in the second concrete layer.

[0004] The above-mentioned outsourced column base structure is constructed using cast-in-place concrete, which requires on-site tying of the steel frame and formwork pouring of concrete. The process is complicated, slow, and the quality is difficult to guarantee. It also greatly increases the overall construction time. Summary of the invention

[0005] The present invention provides a circumferential prestressed assembled outsourced column base and a construction method, which has the characteristics of convenient processing and installation, reliable force transmission, good mechanical properties, energy saving and emission reduction, etc., and provides guidance for the design and construction of assembled outsourced column bases.

[0006] The technical problem to be solved is: the existing outsourced column base structure is constructed with cast-in-place concrete, which requires on-site tying of the steel frame and formwork casting of concrete. The process is complicated, slow, and the quality is difficult to guarantee, which also greatly increases the overall construction time.

[0007] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0008] The present invention discloses a circumferential prestressed assembled outsourcing column foot, comprising a foundation, a steel column installed on the foundation, and an outsourcing module, wherein the steel column is provided with pins on the outside;

[0009] The outer package module is a prefabricated reinforced concrete structure, which is wrapped on the steel column and includes four outer package column foot blocks, which are spliced ​​together in the middle to enclose a space for passing the steel column; the outer package column foot blocks are provided with pin holes for inserting pins;

[0010] The four outer column foot blocks are provided with prestressed channels connected in sequence, and prestressed tendons are arranged in the prestressed channels. One of the outer column foot blocks is provided with an internal interface and an external interface connected to the outside of the outer column foot block. One end of the prestressed tendon is anchored at the internal interface, and the other end passes through the prestressed channels on the four outer column foot blocks in sequence, passes through the external interface and is anchored;

[0011] The foundation is provided with reserved steel bars, and the lower end of the outer column foot block is provided with a grouting sleeve connected to the reserved steel bars;

[0012] Micro-expansive concrete is poured into the steel columns, and cement slurry is poured between the steel columns and the outer modules.

[0013] The present invention provides a circumferential prestressed assembled externally wrapped column foot. Further, the cross section of the externally wrapped module is rectangular, and the externally wrapped module is equally divided into four externally wrapped column foot blocks along its diagonal direction.

[0014] The present invention discloses a circumferential prestressed assembled externally wrapped column base. Further, the externally wrapped column base block comprises two layers of inner and outer longitudinal reinforcements and stirrups connecting the longitudinal reinforcements.

[0015] The present invention provides a circumferential prestressed assembled external column base. Further, a grouting hole connected to a pin hole is provided on the top of the external column base block; and a grouting hole and a grouting hole are provided on the side of the external column base block.

[0016] The present invention provides a circumferential prestressed assembled externally packaged column base. Further, the prestressed tendons are arranged in multiple rows at intervals along the height direction of the externally packaged module.

[0017] The present invention provides a circumferential prestressed assembled outsourced column base. Further, a base plate is provided at the bottom of the steel column, anchor bolts are pre-embedded on the foundation, and the base plate is fixed to the anchor bolts by nuts.

[0018] The present invention provides a circumferential prestressed assembled externally wrapped column foot. Furthermore, the externally wrapped column foot blocks are spliced ​​in a concave-convex tenon manner.

[0019] The present invention provides a circumferential prestressed assembled externally wrapped column base. Further, the tensioning end and the anchoring end of the prestressed tendon are both anchored by a single-hole anchor.

[0020] A construction method comprises the following steps:

[0021] Step 1: After the foundation installation and positioning is completed, hoist the steel column, pass the anchor bolts extending from the foundation through the anchor bolt holes on the bottom plate, and tighten the nuts to install and position the steel column;

[0022] Step 2: Install the outer column foot block, and thread the prestressed tendons as the outer column foot block is installed. When the prestressed tendons are threaded, the prestressed tendons are anchored at the internal interface; and the pins are inserted into the pin holes, and the longitudinal reinforcement located outside the outer column foot block is connected to the reserved steel bars through the grouting sleeve. After installation and positioning, grouting is performed in the grouting sleeve;

[0023] Step 3: tension, anchor and seal the prestressed tendons passing through the external interface;

[0024] Step 4: Pour micro-expansive concrete into the steel column and pour cement slurry between the steel column and the outer module.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] 1. The outsourced column base is designed to be assembled, and the components are produced in factories, which greatly improves the quality and enables on-site assembly and construction, saving water, electricity, materials, and the environment. Moreover, factory production is not affected by the external weather and other natural environments, so the construction period is more controllable, and the production efficiency is much higher than manual work, which saves construction time;

[0027] 2. Adding circumferential prestressed bars in the outer module can effectively connect the modules into a whole and improve the overall performance of the assembled column foot. The circumferential prestressed bars can be used as stirrups to resist shear, thus reducing the amount of ordinary stirrups in the column foot. It is estimated that the amount of stirrups can be reduced by 12.5%;

[0028] In addition, the hoop effect of the annular prestressed tendons can put the concrete in the column base in a three-dimensional stress state, improve the crack resistance and ultimate strength of the concrete, and thus improve the lateral stiffness and seismic performance of the prefabricated column base;

[0029] 3. Splicing the column base from the diagonal line has the following advantages:

[0030] 3.1. High degree of standardization Symmetrical cutting and splicing along the diagonal lines can reduce the number of module types and increase the degree of standardization. For square column bases, only one standardized module needs to be processed; and it is convenient to anchor the prestressed tendons;

[0031] 3.2. Conducive to assembly. Due to the high degree of standardization of the modules, it is easy to achieve standardized design, modular processing, and mechanized construction. Effectively ensure the quality of the finished column base;

[0032] 3.3. Good mechanical properties. The column base is mainly subjected to vertical and horizontal loads. Each section is in a state of combined compression, bending and shearing. There is no assembly gap on the side when it is cut and assembled along the diagonal line, which will not affect the lateral stiffness of the column base. Therefore, it has strong bearing capacity and seismic resistance.

[0033] 3.4. Good economic benefits. Since only one standardized module needs to be designed, the design cost is low. During the prefabrication stage, the use of component templates can be effectively reduced, reducing processing costs. During on-site installation, since each module is directly connected to the front of the steel column, the operation is simple and convenient, the degree of mechanization is high, the construction is fast, the construction period is short, and the construction cost is effectively reduced. Due to the high degree of assembly and convenient disassembly and assembly, energy saving, emission reduction, low carbon and environmental protection can be achieved throughout the life cycle of the assembled column base, effectively improving the direct and indirect economic benefits of assembled buildings.

[0034] 4. Prefabricated externally wrapped column bases are compared to exposed column bases. Externally wrapped column bases are made by pouring reinforced concrete of a certain height and thickness at the bottom of the exposed column base. The internal force will be borne by the steel column and the reinforced concrete outer layer. At the same time, because the outer layer provides lateral support for the column base, the foundation plays a role in embedding the steel column. Compared with exposed column bases, externally wrapped column bases have the advantages of high rigidity, small deformation, high bearing capacity, and good seismic performance.

[0035] 5. The present application also provides a prefabricated column base installation and tensioning process, which is suitable for the installation and tensioning construction of prefabricated column bases, has a positive role in improving the construction quality of prestressed column bases, and provides guidance for the design and construction of prefabricated outsourced column bases.

[0036] The present invention will be further described below in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a elevation view of the steel bar arrangement of the present invention;

[0038] Figure 2 It is a plan view of the arrangement of the prestressed ducts of the present invention;

[0039] Figure 3 This is a plan view of the steel bar arrangement of the outsourcing module of the present invention;

[0040] Figure 4 It is a schematic diagram of the basic structure of the present invention;

[0041] Figure 5 This is a schematic diagram of the steel column structure of the present invention;

[0042] Figure 6 This is a schematic diagram of the structure of the outsourcing module of the present invention;

[0043] Figure 7 It is a grouting and grouting hole position diagram of the grouting sleeve of the present invention;

[0044] Figure 8 It is a schematic diagram of the structure of the outsourced column foot block of the present invention.

[0045] Reference numerals:

[0046] 1. Foundation; 2. Steel column; 3. Outer module; 3.1. Outer column foot block; 3.2. Pin hole; 3.3. Grouting hole; 3.4. Prestressed channel; 3.5. Prestressed tendons; 3.6. Internal interface; 3.7. External interface; 3.8. Longitudinal reinforcement; 3.9. Stirrups; 4. Anchor bolt; 5. Pin; 6. Bottom plate; 7. Angle steel; 8. Reserved steel bar; 9. Grouting sleeve; 10. Grouting hole; 11. Grouting hole. DETAILED DESCRIPTION

[0047] like Figure 1-Figure 8 As shown, the present invention discloses a circumferential prestressed assembled externally wrapped column foot and a construction method, the structure includes a foundation 1, a steel column 2 installed on the foundation 1, and an externally wrapped module 3 wrapped outside the steel column 2, the steel column 2 is poured with micro-expansion concrete, and cement slurry is poured between the steel column 2 and the externally wrapped module 3. The foundation 1 is a prefabricated concrete structure, which can be a concrete cross beam strip foundation 1, and the foundation 1 is pre-buried with an anchor bolt 4 with the upper end extending out of the foundation 1; the outer side of the steel column 2 is fixed with a pin 5, and the bottom is fixed with a bottom plate 6, and an angle steel 7 is welded between the corner of the steel column 2 and the bottom plate 6 to strengthen the bottom rigidity, and the anchor bolt 4 passes through the anchor bolt hole on the bottom plate 6 and is tightened by a nut to install the steel column 2 on the foundation 1.

[0048] The outer package module 3 is a prefabricated reinforced concrete structure with a rectangular cross-section. It is equally divided into four outer package column base blocks 3.1 along the diagonal direction of the outer package module 3. The four outer package column base blocks 3.1 are spliced ​​together in the middle to enclose a space for passing the steel column 2. The outer package column base block 3.1 is provided with a pin hole 3.2 for inserting the pin 5, and the top of the outer package column base block 3.1 is provided with a grouting hole 3.3 connected to the pin hole 3.2.

[0049] The four outer column foot blocks 3.1 are provided with prestressed channels 3.4 that are connected in sequence along the circumference of the outer module 3. Prestressed tendons 3.5 are arranged in the prestressed channels 3.4. One of the outer column foot blocks 3.1 is provided with an internal interface 3.6 and an external interface 3.7 that is connected to the outside of the outer column foot block 3.1. The internal interface 3.6 is located at the end of the prestressed channel 3.4. One end of the prestressed tendon 3.5 is anchored at the internal interface 3.6, and the other end passes through the prestressed channels 3.4 on the four outer column foot blocks 3.1 in sequence and passes through the external interface 3.7 and is anchored. The prestressed channel 3.4 is arranged in a ring shape and is disconnected from the external interface 3.7 at the closed internal interface 3.6. Prestressed tendons 3.5 are selected from prestressed steel strands. The prestressed channel 3.4 is provided with arc sections at the corners of the outer module 3 to facilitate the direction change of the prestressed tendons 3.5. The anchoring of the prestressed tendons 3.5 adopts single-hole anchoring.

[0050] The cross-section of the outer column base block 3.1 is trapezoidal, and includes inner and outer layers of longitudinal reinforcement 3.8 and stirrups 3.9 connecting the longitudinal reinforcement 3.8. The outer longitudinal reinforcement 3.8 is arranged along the lower bottom surface of the outer column base block 3.1, the inner longitudinal reinforcement 3.8 is arranged along the upper bottom surface of the outer column base block 3.1, and the stirrups 3.9 are arranged along the contour direction of the outer column base.

[0051] Reserved steel bars 8 are arranged on the foundation 1, and the longitudinal bars 3.8 of the outer layer of the outer column foot block 3.1 are connected to the reserved steel bars 8 through a grouting sleeve 9. Grouting holes 10 and grouting holes 11 are arranged on the side of the outer column foot block 3.1.

[0052] A plurality of prestressed tendons 3.5 are arranged at intervals along the height direction of the outer packaging module 3. The present application takes three tendons as an example for explanation. The three prestressed tendons 3.5 are arranged at the upper, middle and lower positions of the outer packaging module 3 respectively.

[0053] Among them, the outer column base blocks 3.1 are spliced ​​by using the method of mortise and tenon, which plays the role of positioning connection.

[0054] The construction method comprises the following steps:

[0055] Step 1: After the foundation 1 is installed and positioned, the steel column 2 is hoisted, and the anchor bolts 4 extending from the foundation 1 are passed through the anchor bolt holes on the base plate 6, and the steel column 2 is installed and positioned by tightening the nuts.

[0056] Step 2: Install the outer column base block 3.1, and as the outer column base block 3.1 is installed, the prestressed tendons 3.5 are inserted along the annular prestressed channel 3.4. When the prestressed tendons 3.5 are inserted, the anchoring end of the prestressed tendons 3.5 is anchored at the internal interface 3.6, and the tensioning end is inserted from the external interface 3.7; align the pin hole 3.2 with the pin 5 on the side of the steel column 2, so that the pin 5 is inserted into the pin hole 3.2, and at the same time, the four outer column base blocks 3.1 are horizontally positioned and connected by concave and convex tenons, and the longitudinal reinforcement 3.8 located on the outside of the outer column base block 3.1 is connected to the reserved steel bar 8 through the grouting sleeve 9. After installation and positioning, grouting is performed in the grouting sleeve 9.

[0057] Step 3: Tension, anchor and seal the prestressed tendons 3.5 passing through the external interface 3.7

[0058] Step 4: Pour micro-expansive concrete into the steel column 2, and pour cement slurry between the steel column 2 and the outer package module 3.

[0059] The embodiments described above are merely descriptions of preferred implementation modes of the present invention and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A circumferential prestressed assembled outsourced column foot, characterized in that: It comprises a foundation (1), a steel column (2) installed on the foundation (1), and an external packaging module (3), wherein the steel column (2) is provided with a pin (5) on the outside; The outer package module (3) is a prefabricated reinforced concrete structure, which is wrapped around the steel column (2), and includes four outer package column foot blocks (3.1). The four outer package column foot blocks (3.1) are spliced ​​together in the middle to enclose a space for passing the steel column (2); the outer package column foot blocks (3.1) are provided with pin holes (3.2) for inserting pins (5); The four outer column base blocks (3.1) are provided with prestressed channels (3.4) that are connected in sequence, and the prestressed channels (3.4) are provided with prestressed tendons (3.5). One of the outer column base blocks (3.1) is provided with an internal interface (3.6) and an external interface (3.7) that is connected to the outside of the outer column base block (3.1). One end of the prestressed tendon (3.5) is anchored at the internal interface (3.6), and the other end passes through the prestressed channels (3.4) on the four outer column base blocks (3.1) in sequence, passes out from the external interface (3.7) and is anchored; A reserved steel bar (8) is provided on the foundation (1), and a grouting sleeve (9) connected to the reserved steel bar (8) is provided at the lower end of the outer column foot block (3.1); Micro-expansive concrete is poured into the steel column (2), and cement slurry is poured between the steel column (2) and the outer package module (3).

2. The annular prestressed assembled external column foot according to claim 1, characterized in that: The cross section of the outer packaging module (3) is rectangular, and the outer packaging module (3) is equally divided into four outer packaging column foot blocks (3.1) along its diagonal direction.

3. The annular prestressed assembled external column foot according to claim 2, characterized in that: The outer column foot block (3.1) comprises two layers of inner and outer longitudinal reinforcements (3.8) and stirrups (3.9) connecting the longitudinal reinforcements (3.8).

4. The annular prestressed assembled external column foot according to claim 1, characterized in that: The top of the outer column foot block (3.1) is provided with a grouting hole (3.3) which is in communication with the pin hole (3.2); and the side of the outer column foot block (3.1) is provided with a grouting hole (10) and a grouting hole (11).

5. The annular prestressed assembled external column foot according to claim 1, characterized in that: The prestressed tendons (3.5) are arranged in multiple rows at intervals along the height direction of the outer packaging module (3).

6. The annular prestressed assembled external column foot according to claim 1, characterized in that: A base plate (6) is provided at the bottom of the steel column (2), anchor bolts (4) are pre-buried on the foundation (1), and the base plate (6) is fixed to the anchor bolts (4) by nuts.

7. The annular prestressed assembled external column foot according to claim 1, characterized in that: The outer column foot blocks (3.1) are spliced ​​with each other in a concave-convex tenon manner.

8. The annular prestressed assembled external column foot according to claim 1, characterized in that: The tensioning end and the anchoring end of the prestressed tendon (3.5) are both anchored by a single-hole anchor.

9. A construction method, comprising the annular prestressed assembled external column foot according to any one of claims 1 to 8, characterized in that: The following steps are involved: Step 1: After the foundation (1) is installed and positioned, the steel column (2) is hoisted, and the anchor bolts (4) extending from the foundation (1) are passed through the anchor bolt holes on the base plate (6), and the steel column (2) is installed and positioned by tightening the nuts; Step 2: Install the outer column foot block (3.1), and insert the prestressed tendons (3.5) as the outer column foot block (3.1) is installed. When the prestressed tendons (3.5) are inserted into the bundle, the prestressed tendons (3.5) are anchored at the internal interface (3.6); and the pin (5) is inserted into the pin hole (3.2), and the longitudinal reinforcement (3.8) located outside the outer column foot block (3.1) is connected to the reserved steel bar (8) through the grouting sleeve (9). After installation and positioning, grouting is performed in the grouting sleeve (9); Step 3: tensioning, anchoring and anchoring the prestressed tendons (3.5) passing through the external interface (3.7); Step 4: pouring micro-expansive concrete into the steel column (2), and pouring cement slurry between the steel column (2) and the outer module (3).

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