Construction method for prefabricating and binding pier column top cap steel bars

Abstract

The invention relates to a pier column top cap steel bar prefabricating and binding construction method, and belongs to the technical field of bridge construction.The method comprises the steps that firstly, a jig frame is arranged in a processing factory, a bottom plate is arranged firstly, then a plurality of stand columns are arranged on the bottom plate, and the middle sections of the stand columns are welded through angle steel to form an annular lower-layer positioning plate; the top ends of the stand columns are welded through angle steel to form an annular upper-layer positioning plate, and the lower-layer positioning plate and the upper-layer positioning plate are parallel to the ground; secondly, steel bars are bound on the jig frame; thirdly, the jig frame and the bound reinforcing steel bars are hoisted to the pier top to be positioned, and construction is conducted in the next step; the reinforcing steel bars are positioned by arranging the upper-layer positioning plate and the lower-layer positioning plate, the reinforcing steel bars are positioned by the two layers of positioning plates connected with the main body structure in a welded mode, the probability of inaccurate positioning caused by deformation is reduced, and the positioning precision is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of bridge construction, and in particular relates to a construction method for prefabricating and binding steel bars of a pier column top cap. Background Art

[0002] Rebar binding is an important part of concrete structure construction and is widely used in buildings, bridges, infrastructure and other projects. As the scale and complexity of projects increase, it becomes increasingly important to ensure the strength and stability of concrete structures. As the main reinforcing material in concrete, the configuration and binding quality of rebar directly affect the safety and durability of the project.

[0003] For the binding of the cap beam or top cap of the bridge, the cap beam is a prestressed cap beam. The general cap beam reinforcement binding adopts a spliced ​​structure and adopts a crane to assist in the installation of the skeleton piece. This construction method is difficult to operate, has a low safety factor for high-altitude construction, is not efficient, has low precision, and is not conducive to the control of the cap beam protective layer and the quality of the steel bars. For this reason, Chinese patent CN214271705U discloses a cap beam reinforcement binding frame, including an external frame, a beam bottom reinforcement binding platform, a latch and a ladder; the external frame includes a first structure, a second structure and a third structure; a plurality of first structures are arranged at intervals; a plurality of second structures; a plurality of third structures are arranged at intervals; The first structure is a hollow square frame structure; the second structure is fixed to both sides of the first structure and is located on the extension line of the lower end of the first structure; the third structure is fixed to the outside of two adjacent first structures and is located on the second structure; the beam bottom reinforcement binding platform is located in multiple first structures; the width of the beam bottom reinforcement binding platform is smaller than the width of the hollow structure of the first structure, and the height is smaller than the height of the first structure; the ladder is located outside the third structure; the pins are respectively arranged at the upper ends of both sides of the first structure, which has the advantages of ensuring the quality and accuracy of the prestressed cap beam construction and improving the safety factor and construction efficiency during the construction process;

[0004] However, the steel bars in the steel cage are mainly positioned through the comb plate structure pins in the first structure. The pins themselves have weak structural strength and fewer connection points with the frame body. When assuming the function of positioning the steel bars, the probability of deformation is high, resulting in a high probability of inaccurate positioning and low positioning accuracy. Therefore, a construction method for prefabricated binding of pier top cap steel bars with high positioning accuracy is needed. Summary of the invention

[0005] In order to solve the above problems existing in the prior art, the present invention provides a construction method for prefabricating and binding steel bars of a pier top cap, which has the characteristic of high positioning accuracy.

[0006] The purpose of the present invention can be achieved through the following technical solutions:

[0007] A construction method for prefabricating and binding steel bars of a pier column top cap comprises the following steps:

[0008] Step 1: Set up a tire frame in the processing plant, first set up a bottom plate, then set up a number of columns on the bottom plate, and use angle steel to weld a ring-shaped lower positioning plate in the middle of the column, and use angle steel to weld a ring-shaped upper positioning plate at the top of the column, and make the lower positioning plate and the upper positioning plate parallel to the ground;

[0009] Step 2: Tie the steel bars on the tire frame;

[0010] Step 3: Hoist the frame and the bound steel bars to the top of the pier for positioning, and then proceed to the next step of construction.

[0011] As a preferred technical solution of the present invention, the step one further includes: setting shear braces between adjacent columns.

[0012] As a preferred technical solution of the present invention, step one also includes: the operator calculates the current long side size of the steel cage, and increases the prestress of the shear brace when the size exceeds a threshold, and reduces the prestress of the shear brace when the size is below the threshold.

[0013] As a preferred technical solution of the present invention, step one also includes: the operator calculates the current long side dimension a of the steel cage and adjusts the prestress of the shear brace to F, wherein F=a / a0×F0×c, a0 is a pre-input dimension threshold, F0 is a pre-input dimension reference value, and c is a pre-input correction value.

[0014] As a preferred technical solution of the present invention, step one also includes: setting two connecting channel steels, taking a surface perpendicular to the ground and coinciding with the axial centerline of the tire frame as a reference surface, making the two connecting channel steels symmetrical along the reference surface, setting a slot on the connecting channel steel, and detachably setting a hanger on the slot, and the slot is set in a position to ensure that the hanger is in contact with the bound steel cage after the setting is completed.

[0015] As a preferred technical solution of the present invention, step one also includes: the operator calculates the current long side size of the steel cage, and increases the thickness of the connecting channel steel when the size exceeds a threshold, and reduces the thickness of the connecting channel steel when the size is lower than the threshold.

[0016] The beneficial effects of the present invention are:

[0017] (1) The upper and lower positioning plates are provided to position the steel bars. Compared with positioning the steel bars in the steel cage by means of the comb plate structure pins, the pins are more likely to deform when assuming the function of positioning the steel bars, resulting in a greater probability of inaccurate positioning and lower positioning accuracy. In this solution, two layers of positioning plates welded to the main structure are provided to position the steel bars, thereby reducing the probability of inaccurate positioning caused by deformation and improving positioning accuracy.

[0018] (2) By setting shear braces between adjacent columns, when a column tends to deform, the shear braces, with the cooperation of other columns, enable the column to maintain its original shape, reduce the probability of column deformation, and further reduce the probability of changes in the remaining steel bars, thereby improving positioning accuracy;

[0019] (3) By increasing the prestress of the shear brace as the size of the long side of the steel cage increases, and decreasing the prestress as the size of the long side of the steel cage decreases, the shear brace prestress is increased when the size of the steel cage is large and the shear brace prestress needs to be increased accordingly, thereby reducing the probability of deformation and improving the positioning accuracy. When the size of the steel cage is small and a large prestress is not required, and a large prestress has a probability of causing the column to be deformed by the shear brace force, the prestress is reduced, thereby reducing the probability of column deformation and improving the positioning accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to facilitate understanding by those skilled in the art, the present invention is further described below with reference to the accompanying drawings.

[0021] Figure 1 It is a schematic diagram of the structure of the present invention;

[0022] Figure 2 It is a plan view of the upper positioning plate of the present invention;

[0023] Figure 3 It is a plan view of the lower positioning plate of the present invention;

[0024] Description of main component symbols:

[0025] In the figure: 1. Upper positioning plate; 2. Lower positioning plate; 3. Column; 4. Hanger; 5. Connecting channel steel. DETAILED DESCRIPTION

[0026] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the specific implementation methods, structures, features and effects of the present invention are described in detail below in conjunction with the accompanying drawings and preferred embodiments.

[0027] See also Figure 1-3 A construction method for prefabricating and binding steel bars of a pier column top cap comprises the following steps:

[0028] Step 1: Set up a tire frame in the processing plant, first set up a bottom plate, then set up a number of columns 3 on the bottom plate, and use angle steel to weld the middle section of the column 3 to form a ring-shaped lower positioning plate 2, and use angle steel to weld the top of the column 3 to form a ring-shaped upper positioning plate 1, and make the lower positioning plate 2 and the upper positioning plate 1 parallel to the ground;

[0029] Specifically, the bottom plate is rectangular, and the rectangular bottom plate is placed on the ground parallel to the ground. A plurality of columns 3 perpendicular to the bottom plate are welded on the bottom plate. In this embodiment, a column 3 is arranged at the midpoint of each of the two short sides of the rectangular bottom plate, and four columns 3 are arranged at each of the two long sides, and the four columns 3 arranged on the long sides are arranged at equal distances between adjacent columns;

[0030] Subsequently, the lower positioning plate 2 is assembled. The lower positioning plate 2 is an annular structure formed by welding straight and arc-shaped angle steels. Specifically, the annular structure includes two semicircular arcs. The line connecting the centers of the two semicircular arcs is perpendicular to the line connecting the two ends of any arc. At the same time, the annular structure also includes two straight lines, which are respectively connected to one end of the two arcs. At this time, the shape of the lower positioning plate 2 is similar to the shape of a standard 400-meter track and field runner.

[0031] After the lower positioning plate 2 is assembled, the two straight sections of the lower positioning plate 2 are abutted against the eight columns 3 set on the long sides of the rectangular bottom plate, the midpoints of the two arc sections are respectively abutted against the two columns 3 set on the short sides of the rectangular bottom plate, and the abutment points of the lower positioning plate 2 and the columns 3 are welded to complete the fixed connection between the lower positioning plate 2 and the columns 3.

[0032] Then assemble the upper positioning plate 1, the structure of the upper positioning plate 1 is consistent with the lower positioning plate 2, and the setting method is consistent with the lower positioning plate 2, both of which are first abutted against a number of columns 3 and then welded to the columns 3, and the upper positioning plate 1 is welded and set on the top of the column 3;

[0033] After the lower positioning plate 2 and the upper positioning plate 1 are set, the lower positioning plate 2 and the upper positioning plate 1 form a stable support structure, and steel bars can be placed on the upper surface. At this time, step 2 is performed: tying steel bars on the tire frame. After the operator places a number of steel bars at the corresponding positions of the lower positioning plate 2 and the upper positioning plate 1, the steel bars are tied to complete the tying of the steel cage;

[0034] After the binding is completed, step three is performed: the tire frame and the bound steel bars are hoisted to the pier top for positioning, and the next step of construction is carried out. Specifically, after the pier cap steel bars are tied, the steel cage is hoisted into the pier body formwork by a crane;

[0035] In this embodiment, the column 3, the annular upper positioning plate 1 and the annular lower positioning plate 2 are all welded by 150*90*10 angle steel;

[0036] The steel bars are positioned by setting an upper positioning plate 1 and a lower positioning plate 2. Compared with positioning the steel bars in the steel cage by means of a comb plate structure pin, since the pin has a greater probability of deformation when assuming the function of positioning the steel bars, resulting in a greater probability of inaccurate positioning and lower positioning accuracy, this solution positions the steel bars by setting two layers of positioning plates welded to the main structure, thereby reducing the probability of inaccurate positioning caused by deformation and improving positioning accuracy.

[0037] In the above structure, the column 3 is fixed by the bottom plate and the two-layer positioning plate. When the column 3 is deformed, various parts of the entire tire frame will also be deformed. At this time, several parts used to fix the steel bars will also be deformed. In order to reduce the probability of deformation of the column 3, step one also includes: setting a shear brace between adjacent columns 3;

[0038] Specifically, since four columns 3 are provided on each long side of the bottom plate, three shear braces need to be provided on the four columns 3 on each long side, and a total of six shear braces are provided on the entire tire frame, one end of each shear brace is connected to one of the columns 3 of two adjacent columns 3, and the other end is connected to the other column 3 of the two adjacent columns 3;

[0039] When the column 3 tends to deform, the shear force bracing, with the cooperation of other columns 3, enables the column 3 to maintain its original shape;

[0040] By arranging shear braces between adjacent columns 3, when a column 3 tends to deform, the shear braces, with the cooperation of other columns 3, enable the column 3 to maintain its original shape, thereby reducing the probability of deformation of the column 3, and further reducing the probability of changes in the remaining parts used for national steel bars, thereby improving positioning accuracy.

[0041] In the above structure, the shear brace has a certain prestress by itself, and exerts a reaction force on the column 3 to maintain the shape of the column 3 when the column 3 is deformed. However, when the prestress is larger, there is a probability that the column 3 does not deform, and the force in the opposite direction of the deformation of the column 3 still causes the column 3 to be deformed for a long time. When the prestress is too small, the shear brace cannot play a supporting role.

[0042] At the same time, the larger the size of the steel cage, the greater the pressure on the column 3, the shear brace and the two positioning plates. At this time, the column 3 relies more on the prestress of the shear brace to maintain its original position. At this time, the prestress of the shear brace needs to be increased accordingly. Similarly, when the size of the steel cage is smaller, the pressure on the column 3, the shear brace and the two positioning plates is smaller. At this time, the column 3 does not need to rely too much on the prestress of the shear brace;

[0043] To this end, step one also includes: the operator calculates the current long side size of the steel cage, and increases the prestress of the shear brace when the size exceeds a threshold, and reduces the prestress of the shear brace when the size is below the threshold;

[0044] In this embodiment, the operator calculates the current long side dimension a of the steel cage and adjusts the prestress of the shear brace to F, where F = a / a0×F0×c, a0 is the pre-entered dimension threshold, F0 is the pre-entered dimension reference value, and c is the pre-entered correction value;

[0045] In this embodiment, the steel cage is in the shape of a quadrangular prism or a cylinder. When the steel cage is in the shape of a quadrangular prism, the long side dimension is the length of the longest side in the quadrangular prism structure; when the steel cage is in the shape of a cylinder, the long side dimension is the length of the central axis of the cylinder;

[0046] When the value of a is large, it means that the size of the steel cage is large, and the shear brace prestressing needs to be increased accordingly. At this time, the value of F = a / a0×F0×c increases with the increase of a. When the prestressing force of the shear brace is adjusted to F, the shear brace prestressing force is increased when the weight of the steel bar is large, a larger structural strength is required, and the prestressing force of the shear brace is increased accordingly.

[0047] Similarly, when the value of a is small, it means that the size of the steel cage is small and a large shear brace prestress is not required. At this time, the value of F = a / a0×F0×c decreases as a decreases. When the prestress of the shear brace is adjusted to F, the shear brace prestress is reduced when the weight of the steel bar is small and a large structural strength and shear brace prestress are not required.

[0048] By increasing the prestress of the shear brace as the size of the long side of the steel cage increases, and reducing the prestress as the size of the long side of the steel cage decreases, the shear brace prestress is increased when the steel cage is large and the shear brace prestress needs to be increased accordingly, thereby reducing the probability of deformation and improving the positioning accuracy. When the steel cage is small and no large prestress is required, and there is a probability that the large prestress will cause the column 3 to be deformed by the shear brace support force, the prestress is reduced, thereby reducing the probability of deformation of the column 3 and improving the positioning accuracy.

[0049] In the above process, after the steel cage is tied, it needs to be hoisted from the processing plant to the predetermined pier column top cap position. If the sling 4 is directly connected to the steel cage, there is a probability that the lifting traction force will be concentrated on a certain point of the steel cage, which will cause the steel cage to deform during the hoisting process. In order to improve the force uniformity, step one also includes: setting two connecting channel steels 5, taking the surface perpendicular to the ground and coinciding with the axial line of the tire frame as the reference surface, making the two connecting channel steels 5 symmetrical along the reference surface, setting a card slot on the connecting channel steel 5, and detachably setting the sling 4 on the card slot, and the card slot setting position ensures that the sling 4 is abutted against the tied steel cage after the setting is completed;

[0050] Two connecting channel steels 5 are respectively arranged on two groups of columns 3 connected to the long sides of the bottom plate, that is, one connecting channel steel 5 and four columns 3 arranged on one long side of the bottom plate, and the other connecting channel steel 5 and four columns 3 arranged on the other long side of the bottom plate, and are parallel to the ground. A slot is dug above each connecting channel steel 5, and a hanger 4 is provided with a groove to match the slot. The slot and the groove can be separated and embedded. When the groove and the slot are embedded with each other, the hanger 4 is arranged on the slot, and the upper end of the hanger 4 abuts against the lower edge of the steel bars on the top surface of the steel cage;

[0051] When lifting, the crane lifts the lifting device 4 away from the connecting channel steel 5, and the upper end of the lifting device 4 abuts against the lower edge of the top surface of the steel cage, exerting an upward force on the steel cage, completing the lifting of the steel cage by the lifting device 4;

[0052] By setting the connecting channel steel 5 and the hanger 4 on the connecting channel steel 5, the connecting channel steel 5 can further improve the tire frame.

[0053] In the above structure, the tire frame exerts a reaction force on the steel cage when the steel cage is placed on it through its own structural strength to maintain the positioning of the steel cage. The larger the long side size of the steel cage, the greater the deadweight of the steel cage, and the greater the required structural strength. At this time, it is necessary to improve the fixing effect of the connecting channel steel 5 on the tire frame body. To this end, step one also includes: the operator calculates the current long side size of the steel cage, and increases the thickness of the connecting channel steel 5 when the size exceeds the threshold, and reduces the thickness of the connecting channel steel 5 when the size is lower than the threshold;

[0054] When the long side size of the steel cage exceeds the threshold, it is necessary to improve the fixing effect of the connecting channel steel 5 on the tire frame body. At this time, the structural strength of the thickened connecting channel steel 5 is improved, thereby improving the structural strength of the tire frame.

[0055] When the long side dimension of the steel cage is smaller than the threshold value, the excessively thick connecting channel steel 5 has a large self-weight, which will weaken the structural strength of the column 3 and the frame body. At this time, reducing the thickness of the connecting channel steel 5 can reduce the weakening effect of the self-weight of the connecting channel steel 5 on the structural strength.

[0056] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technical personnel in this field can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A construction method for prefabrication and binding of pier column top cap reinforcement, characterized in that: The following steps are involved: Step 1: Set up a tire frame in the processing plant, first set up a bottom plate, then set up a number of columns on the bottom plate, and use angle steel to weld a ring-shaped lower positioning plate in the middle of the column, and use angle steel to weld a ring-shaped upper positioning plate at the top of the column, and make the lower positioning plate and the upper positioning plate parallel to the ground; Step 2: Tie the steel bars on the tire frame; Step 3: Hoist the frame and the bound steel bars to the top of the pier for positioning, and then proceed to the next step of construction.

2. A construction method for prefabrication and binding of pier column top cap reinforcements according to claim 1, characterized in that: The step one also includes: setting shear braces between adjacent columns.

3. A construction method for prefabrication and binding of pier column top cap reinforcements according to claim 2, characterized in that: The step one also includes: the operator calculates the current long side size of the steel cage, and increases the prestress of the shear brace when the size exceeds a threshold, and reduces the prestress of the shear brace when the size is below the threshold.

4. A construction method for prefabrication and binding of pier column top cap reinforcements according to claim 3, characterized in that: The step one also includes: the operator calculates the current long side dimension a of the steel cage and adjusts the prestress of the shear brace to F, where F=a / a0×F0×c, a0 is a pre-entered dimension threshold, F0 is a pre-entered dimension reference value, and c is a pre-entered correction value.

5. The construction method for prefabrication and binding of pier column top cap reinforcement according to claim 1 is characterized by: The step one also includes: setting two connecting channel steels, taking the surface perpendicular to the ground and coinciding with the axial centerline of the tire frame as the reference surface, making the two connecting channel steels symmetrical along the reference surface, setting a slot on the connecting channel steel, and detachably setting a hanger on the slot, and the slot is set in a position to ensure that the hanger is in contact with the bound steel cage after the setting is completed.

6. A construction method for prefabrication and binding of pier column top cap reinforcements according to claim 5, characterized in that: The step one also includes: the operator calculates the current long side size of the steel cage, and increases the thickness of the connecting channel steel when the size exceeds a threshold, and reduces the thickness of the connecting channel steel when the size is below the threshold.

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