High-throwing concrete construction method for concrete filled steel tubular column

Abstract

The invention belongs to the field of constructional engineering, and provides a high-throwing concrete construction method for a concrete filled steel tubular column, which comprises the following steps: S1, erecting an operation platform; s2, transverse stiffening plates are assembled; s3, the pouring guide pipe extends into the steel pipe concrete column and has a height difference with the to-be-poured surface; s4, the pouring speed is controlled; s5, a vibrating rod is inserted into the concrete and vibrates in a reciprocating mode; and S6, the pouring guide pipe is synchronously lifted upwards in the vertical direction, and the height difference between the bottom of the pouring guide pipe and the concrete liquid level is kept. Compared with the prior art, the method has the advantages that the proper length of the pouring guide pipe is selected to be matched with the dynamic gap between the pouring guide pipe and the hole, so that enough falling kinetic energy can still be kept when concrete penetrates through the transverse stiffening plate, meanwhile, the height from the bottom of the pouring guide pipe to the pouring surface is larger than 4 m, high throwing kinetic energy is guaranteed, and pouring and lifting are carried out at the same time; the dense filling of the concrete is realized, and the quality defects of cavities, segregation, incompactness and the like are avoided.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of building engineering, and particularly relates to a high-throwing concrete construction method for a steel pipe concrete column. BACKGROUND

[0002] The steel pipe concrete column has become the first choice for key stress components such as modern high-rise buildings, super high-rise structures, large-span bridge piers, large sports venues, airport terminal buildings and industrial plants due to high bearing capacity, good ductility, convenient construction, superior fire resistance and good economy. In actual engineering, in order to effectively constrain local buckling of the steel pipe and improve the shear bearing capacity and overall stiffness of the joint area, the design specification (such as Technical Code for Concrete Filled Steel Tubular Structures GB 50936) usually requires setting a transverse stiffening plate (also known as an internal diaphragm) at the beam-column joint or the stress concentration area. These stiffening plates are mostly ring-shaped or cross-shaped steel plates welded to the inner wall of the steel pipe, and a central pouring hole is opened at the position of the column axis to allow the concrete to be poured from top to bottom.

[0003] However, the diameter of the central pouring hole is usually limited by the structural stress requirements, which hinders the traditional high-throwing pouring, specifically, on the one hand, the small hole diameter seriously limits the free flow channel of the concrete; on the other hand, the concrete is prone to aggregate bridging, slurry separation or kinetic energy attenuation when passing through the narrow hole, resulting in the formation of cavities, cracks, concrete segregation and other phenomena under the stiffening plate, which not only weakens the combination between the steel pipe and the concrete, reduces the overall bearing capacity and ductility of the component, but also may cause local corrosion, stress concentration and even brittle failure during service, seriously affecting the structural safety and durability. SUMMARY

[0004] The purpose of the present application is to solve the above-mentioned problems existing in the prior art, and to provide a high-throwing concrete construction method for a steel pipe concrete column, which has a simple structure and improves the concrete pouring quality to ensure stable bearing capacity.

[0005] The purpose of the present application can be achieved by the following technical problems, a high-throwing concrete construction method for a steel pipe concrete column is provided, comprising the steps of:

[0006] S1, before concrete pouring, an operation platform is erected at the edge of the steel pipe concrete column for the construction personnel to perform pouring operation;

[0007] S2, a transverse stiffening plate with a central pouring hole is assembled at the joint of the beam column and the steel pipe concrete column, the central pouring hole is coaxially arranged with the axis of the steel pipe concrete column, and is used for uniformly dispersing the concrete;

[0008] S3, the pouring guide pipe is assembled according to the pouring height, so that the pouring guide pipe can extend into the steel pipe concrete column and pass through the center pouring hole, and the bottom of the pouring guide pipe has a height difference with the pouring surface to be poured;

[0009] S4, the pouring speed of the concrete should be controlled when the concrete is poured into the center pouring hole of the transverse stiffening plate, the air below the transverse stiffening plate is discharged through the flow of the concrete, and then the gap in the steel pipe concrete column is eliminated;

[0010] S5, when the concrete liquid surface rises to a range of 0.8-1.2 meters away from the bottom of any transverse stiffening plate, the high throwing pouring is paused, the vibrating rod is inserted into the concrete and reciprocating vibrated, and the construction personnel use the mallet to knock along the corresponding area of the outer wall of the steel pipe, whether there is hollow or not dense phenomenon is judged by listening, and the pouring of the concrete is continued after confirming the density.

[0011] S6, as the concrete liquid surface continues to rise, the pouring guide pipe is pulled up synchronously along the vertical direction, so that there is always a height difference between the bottom of the pouring guide pipe and the concrete liquid surface, so that the concrete is tamped by the kinetic energy of the concrete.

[0012] In the above-mentioned high-throwing concrete construction method for steel pipe concrete column, in steps S3 and S6: the height difference between the bottom of the pouring guide pipe and the concrete pouring surface is 4m or more.

[0013] In the above-mentioned high-throwing concrete construction method for steel pipe concrete column, a dynamic gap with a single side of 5mm is formed between the center pouring hole and the pouring guide pipe.

[0014] In the above-mentioned high-throwing concrete construction method for steel pipe concrete column, in step S3: the pouring guide pipe is a high-strength alloy steel pipe with an outer diameter of Φ240mm.

[0015] In the above-mentioned high-throwing concrete construction method for steel pipe concrete column, the number of the pouring guide pipes is at least two, and the adjacent two pouring guide pipes are connected through threads.

[0016] In the above-mentioned high-throwing concrete construction method for steel pipe concrete column, in step S1: the width of the operation platform is equal to the diameter of the steel pipe concrete column plus 1.8m.

[0017] In the above-mentioned high-throwing concrete construction method for steel pipe concrete column, in step S5: the vibrating rod is vertically inserted into the concrete, should be inserted densely, and the auxiliary vibrating time is controlled within 60 seconds.

[0018] In the above-mentioned high-throwing concrete construction method for steel pipe concrete column, the operation platform is located below the top opening of the steel pipe concrete column, and the height difference between them is 2mm.

[0019] In the high-throw concrete construction method for a steel pipe concrete column, the length of the single pouring guide pipe is 4 m.

[0020] In the high-throw concrete construction method for a steel pipe concrete column, in step S3, the top end of the pouring guide pipe is also connected with a pouring hopper for storing concrete.

[0021] Compared with the prior art, the present application has the following beneficial effects:

[0022] (1) The high-throw concrete construction method for a steel pipe concrete column can select a suitable pouring guide pipe length according to the actual pouring length of the steel pipe concrete column, cooperate with the dynamic gap between the pouring guide pipe and the hole, make the concrete still have enough falling kinetic energy when passing through the transverse stiffening plate provided with a Φ250 mm hole, utilize the distance between the bottom of the pouring guide pipe and the pouring surface height greater than 4 m to ensure the high-throw kinetic energy, and lift along with pouring, so as to realize the dense filling of the concrete and avoid the quality defects such as cavity, segregation and non-dense filling caused by the stiffening plate hindering in the traditional method.

[0023] (2) The present application sets at least two pouring guide pipes and connects them through threads, which is convenient for flexible assembly and disassembly according to the actual height of the steel pipe concrete column, adapts to different engineering needs, has good sealing, fast installation and firm connection, can effectively prevent concrete leakage, is convenient for transportation and on-site management, and improves the modularization and standardization level of construction.

[0024] (3) The short insertion and vibration, vertical insertion and vibration time control within 60 seconds are adopted in the vibration process, which can effectively remove the bubbles in the concrete, improve the density, avoid excessive vibration to cause concrete segregation or aggregate sinking, is especially suitable for the auxiliary treatment of high-throw self-compacting concrete, takes into account the vibration effect and construction efficiency, and prevents quality defects caused by improper vibration. BRIEF DESCRIPTION OF DRAWINGS

[0025] Fig. 1 is a structural schematic diagram of the present application;

[0026] Fig. 2 is a structural schematic diagram of the transverse stiffening plate on the beam column.

[0027] In the figure, 1 is a steel pipe concrete column; 2 is a transverse stiffening plate; 20 is a center pouring hole; 21 is an exhaust hole; 22 is a fastening bolt; 3 is a beam column; 4 is a pouring guide pipe; and 5 is a pouring hopper. DETAILED DESCRIPTION

[0028] The technical solutions of the present application are further described below in combination with the drawings, but the present application is not limited to these embodiments.

[0029] It should be noted that all directional indications, such as up, down, left, right, front, back, etc., in the embodiments of the present application are only used to explain the relative positional relationship, movement condition, etc. between components in a certain posture (as shown in the drawings), and if the certain posture changes, the directional indications will also change accordingly.

[0030] As shown in Figs. 1-2 A high-throw concrete construction method for a concrete-filled steel tube column 1 according to the present application includes the following steps:

[0031] S1, before concrete pouring, an operation platform is erected at the edge of the concrete-filled steel tube column 1 for the construction personnel to perform pouring operation;

[0032] S2, a transverse stiffening plate 2 with a central pouring hole 20 is assembled at the joint of the beam column 3 and the concrete-filled steel tube column 1, the central pouring hole 20 is coaxially arranged with the axis of the concrete-filled steel tube column 1, and is used to uniformly disperse the concrete;

[0033] S3, the pouring guide pipe 4 is assembled according to the pouring height, so that the pouring guide pipe 4 can extend into the concrete-filled steel tube column 1 and pass through the central pouring hole 20, and the bottom of the pouring guide pipe 4 has a height difference with the surface to be poured;

[0034] S4, when the concrete is poured to the central pouring hole 20 of the transverse stiffening plate 2, the pouring speed should be controlled, the air below the transverse stiffening plate 2 is discharged through the flow of the concrete, and then the gap in the concrete-filled steel tube column 1 is eliminated;

[0035] S5, when the concrete liquid surface rises to a range of 0.8-1.2 meters away from the bottom of any transverse stiffening plate 2, the high-throw pouring is paused, a vibrating rod is inserted into the concrete and reciprocally vibrated, and at the same time a construction personnel uses a wooden hammer to knock along the corresponding area of the outer wall of the steel pipe, whether there is a hollow or a non-dense phenomenon is judged by listening to the sound, and after confirming the density, the pouring of the concrete is resumed;

[0036] S6, as the concrete liquid surface continues to rise, the pouring guide pipe 4 is synchronously pulled upward along the vertical direction, so that there is always a height difference between the bottom of the pouring guide pipe 4 and the concrete liquid surface, so as to knock the concrete into place by the kinetic energy of the concrete.

[0037] The operation platform is erected by using a shaped steel or an assembled scaffold, a surface is paved with an anti-skid steel plate, and a safety guardrail, a ladder and a lighting system are provided, so that a safe and stable operation space is provided for a worker to stand and operate a guide pipe installation, concrete feeding, vibration intervention and knocking detection, and a high-altitude falling risk is significantly reduced.

[0038] A dynamic gap of 5mm in a single side is formed between the center pouring hole 20 and the pouring guide pipe 4.

[0039] It should be noted that the Φ250mm center pouring hole 20 is used in the embodiment, the pouring guide pipe 4 is a high-strength alloy steel pipe with an outer diameter of Φ240mm, and a dynamic gap of 5mm in a single side (that is, 10mm in a double side) is formed between the center pouring hole 20 and the pouring guide pipe 4. The design not only ensures that the pouring guide pipe 4 can smoothly pass through the transverse stiffening plate 2 for up-down pulling operation, but also avoids that the gap is too large to cause waste or pollution of concrete overflowing from the gap. At the same time, the small gap helps to guide the concrete to uniformly diffuse along the inner wall of the steel pipe, promote air exhaust, prevent the formation of a closed air bag, and thus improve the filling density of the concrete.

[0040] Preferably, the material of the high-strength alloy makes the pouring guide pipe 4 not only have excellent compression resistance, bending resistance and wear resistance, and be able to withstand the impact load of high-throwing concrete, but also the large-diameter design is conducive to the smooth passing of large aggregate concrete, reduces the risk of blockage, improves the construction efficiency and continuity, prolongs the service life of the guide pipe, and reduces the construction cost.

[0041] In step S3 and step S6: the height difference between the bottom of the pouring guide pipe 4 and the concrete pouring surface is 4m or more.

[0042] The scheme can select the appropriate pouring guide pipe 4 length according to the actual pouring length of the steel pipe concrete column 1, so as to ensure that the pouring guide pipe 4 passes through the hole (i.e. the center pouring hole 20) of the stiffening plate of the lowermost beam column 3 node, and the height difference between the bottom of the pouring guide pipe 4 and the concrete pouring surface is set to be 4 meters or more (i.e. the free fall height of the concrete is ≥4m), so as to fully utilize the gravitational kinetic energy of the concrete during falling (i.e. to ensure that it always has high throwing energy), so that it has enough impact force when falling into the steel pipe, realizes self-compaction effect, reduces or even avoids the need for artificial vibration, and effectively prevents the concrete from piling up, stratifying or segregating due to insufficient falling height, further ensuring the uniformity and structural integrity of the concrete.

[0043] In step S3: the number of pouring guide pipes 4 is at least two, and the adjacent two pouring guide pipes 4 are connected by threads.

[0044] Preferably, at least two pouring guide pipes 4 are provided and connected by threads, which facilitates flexible assembly and disassembly according to the actual height of the steel pipe concrete column 1, and adapts to different engineering needs; the threaded connection has good sealing performance, fast installation, firm connection, can effectively prevent concrete leakage, and is convenient for transportation and on-site management, thereby improving the modularization and standardization level of construction.

[0045] Further preferably, the length of a single pouring guide pipe 4 is 4m, which matches the minimum height difference (≥4m) required for high throwing, facilitates standardized production and rapid on-site splicing; at the same time, the length takes into account the hoisting convenience and structural stability, avoids bending deformation or installation difficulty caused by too long guide pipes, and improves construction organization efficiency and equipment universality.

[0046] In step S1: the width of the operation platform is equal to the diameter of the steel pipe concrete column 1 plus 1.8m.

[0047] Specifically, before pouring concrete, an operation platform with a certain width is set up around the steel pipe concrete column 1, and the width of the operation platform is set to be the diameter of the steel pipe concrete column 1 plus 1.8m, which provides sufficient operation space for the construction personnel, facilitates safe and efficient pouring, vibration and detection operations, takes into account the platform stability and material economy, avoids resource waste caused by too wide platform or affects construction safety caused by too narrow platform, and significantly improves the safety and convenience of high-altitude operation.

[0048] In step S5: the vibrating rod is vertically inserted into the concrete, and the vibration should be dense and short, and the auxiliary vibration time is controlled within 60 seconds.

[0049] For example, Fig. 1 andFig. 2 As shown, the pouring of the steel pipe concrete in the scheme adopts a vertical high-throwing non-vibrating method, and the kinetic energy generated by the falling of the concrete is used to compact the concrete; and when the concrete is poured to the hole of the stiffening plate of the beam-column joint 3, the pouring speed should be controlled to discharge the air under the stiffening ring through the flow of the concrete, so as to prevent the gap under the stiffening ring; when the pouring height of the concrete is about 1 m to the stiffening plate, since the high-throwing effect is not obvious at this time, the concrete cannot be broken and compacted only by the kinetic energy of the concrete, and the ordinary vibrating rod should be used for auxiliary vibration in this range, and the vibrating rod is vertically inserted and the vibrating time is controlled within 60 seconds, which can effectively remove the air bubbles in the concrete, improve the compactness, and avoid excessive vibration to cause the segregation of the concrete or the sinking of the aggregate, especially suitable for the auxiliary treatment of the high-throwing self-compacting concrete, taking into account the vibrating effect and construction efficiency, and preventing quality defects caused by improper vibration.

[0050] Further, the vibrating rod is vertically inserted into the concrete, and the vibrating rod is used for auxiliary vibration at the position of the stiffening plate; the outer pipe is hit by the artificial wooden hammer, and whether the concrete is compacted is judged according to the sound; each layer is vibrated until the surface of the concrete is flush and no longer obviously lowered, and no air bubbles appear, and the surface emits mortar.

[0051] The operation platform is located below the top opening of the steel pipe concrete column 1, and the height difference between the two is 2 mm.

[0052] The operation platform is arranged only 2 mm below the top opening of the steel pipe concrete column 1, which not only ensures that the platform does not affect the final pouring of the concrete to the design elevation, but also maximizes the proximity to the working surface, facilitating real-time observation of the pouring state by the construction personnel, timely intervention, reducing the risk of high-altitude and edge work, and optimizing the man-machine engineering and construction precision control.

[0053] In step S3, the top end of the pouring guide pipe 4 is also connected with a pouring hopper 5 for storing concrete.

[0054] As shown in Fig. 1 The pouring hopper 5 is connected to the top end of the pouring guide pipe 4, which can temporarily store a certain amount of concrete, buffer the intermittent process of pumping or hoisting, ensure the continuity and stability of the high-throwing pouring, avoid the interruption of the concrete flow caused by the interruption of the supply, and form cold joints or air gaps, so as to ensure the continuity and uniformity of the pouring quality.

[0055] It should be noted that the present embodiment also has an exhaust hole 21 on the transverse stiffening plate 2, as shown in Fig. 2 When the concrete is filled from top to bottom, the gas in the steel pipe concrete column 1 can be discharged through the exhaust hole 21, so that the concrete spreads more evenly along the inner wall of the steel pipe and the bottom surface of the stiffening plate, especially beneficial to filling the edge below the stiffening plate, the welding seam and other easy-to-stagnate areas, and reducing the "dead angle" defects.

[0056] It should be noted that in this invention, the use of terms such as "first," "second," and "a" is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified. The terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two elements or the interaction between two elements, unless otherwise explicitly specified. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0057] Furthermore, the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are feasible for those skilled in the art. If the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0058] The specific embodiments described herein are merely illustrative of the spirit of the invention. Those skilled in the art to which this invention pertains may make various modifications or additions to the described specific embodiments or use similar methods to substitute them, without departing from the spirit of the invention or exceeding the scope defined by the appended claims.

Claims

1. A method for constructing high-level concrete for steel-concrete composite columns, characterized in that, Including the following steps: S1. Before pouring concrete, an operating platform shall be erected at the edge of the steel pipe concrete column for construction personnel to carry out the pouring operation. S2. At the joint between the beam and the steel-concrete composite column, a transverse stiffening plate with a central pouring hole is installed. The central pouring hole is coaxial with the axis of the steel-concrete composite column to uniformly disperse the concrete. S3. The pouring guide pipe is assembled according to the pouring height so that the pouring guide pipe can extend into the steel pipe concrete column and pass through the central pouring hole. At the same time, there is a height difference between the bottom of the pouring guide pipe and the surface to be poured. S4. When the concrete is poured to the center pouring hole of the transverse stiffening plate, the pouring speed should be controlled so that the air under the transverse stiffening plate can be discharged through the flow of concrete, thereby eliminating the gap in the steel-concrete composite column. S5. When the concrete level rises to within 0.8–1.2 meters below any horizontal stiffening plate, stop the high-throw pouring. Use a vibrator to insert into the concrete and vibrate it back and forth. At the same time, the construction workers use a wooden mallet to tap along the corresponding area of ​​the outer wall of the steel pipe. By listening to the sound, they can determine whether there are hollow or loose areas. After confirming that it is dense, resume pouring concrete. S6. As the concrete level continues to rise, the pouring guide pipe is simultaneously pulled upwards in the vertical direction, so that there is always a height difference between the bottom of the pouring guide pipe and the concrete level, so as to compact the concrete through the kinetic energy of the concrete.

2. The method for constructing high-level concrete for steel-concrete composite columns according to claim 1, characterized in that, In steps S3 and S6: the height difference between the bottom of the pouring pipe and the concrete pouring surface is more than 4m.

3. The method for constructing high-level concrete for steel-concrete composite columns according to claim 1, characterized in that, A dynamic gap of 5mm on one side is formed between the central pouring hole and the pouring guide pipe.

4. A method for constructing high-level concrete for steel-concrete composite columns according to claim 2, characterized in that, In step S3: the casting conduit is a high-strength alloy steel pipe with an outer diameter of Φ240mm.

5. A method for constructing high-level concrete for steel-concrete composite columns according to claim 4, characterized in that, The number of the casting conduits is at least two, and adjacent casting conduits are connected by threads.

6. A method for constructing high-level concrete for steel-concrete composite columns according to claim 1, characterized in that, In step S1: the width of the operating platform is equal to the diameter of the steel-concrete composite column plus 1.8m.

7. A method for constructing high-level concrete for steel-concrete composite columns according to claim 1, characterized in that, In step S5: the vibrator is inserted vertically into the concrete, and the insertion should be short and the vibration should be dense, and the auxiliary vibration time should be controlled within 60 seconds.

8. A method for constructing high-level concrete for steel-concrete composite columns according to claim 6, characterized in that, The operating platform is located below the top opening of the steel-concrete composite column, and the height difference between the two is 2mm.

9. A method for constructing high-level concrete for steel-concrete composite columns according to claim 5, characterized in that, The length of a single casting conduit is 4m.

10. A method for constructing high-level concrete for steel-concrete composite columns according to claim 1, characterized in that, In step S3, the top end of the pouring conduit is also connected to a pouring hopper for storing concrete.

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