A zoned prefabricated frame and zoned installation method for variable-section Japanese-shaped hollow thin-walled pier steel bars

Abstract

The present application discloses a variable-section day-shaped thin-walled pier steel bar partition prefabrication jig and a partition installation method, which include a jig assembly and a stiffening skeleton. The jig assembly is divided into an I-shaped jig and two concave jigs. The jig assembly includes a number of columns, a number of first I-beams, a number of binding platforms and a number of crossbeams. The lower parts of the number of columns are connected by the number of first I-beams. The number of binding platforms are installed between two adjacent columns. The number of crossbeams are installed between the number of columns. The stiffening skeleton includes a number of vertical rods and a number of second I-beams. The number of second I-beams are connected between two adjacent vertical rods. The number of second I-beams are respectively connected to the number of crossbeams through main steel bars. In this solution, the steel bars of the day-shaped thin-walled pier are divided into an I-shape and two concave shapes, and are respectively processed and formed on the jig to realize the overall hoisting. The weight after division is reduced, which is convenient for hoisting, and the cross-sectional size is small, which is convenient for splicing.

Description

Technical Field

[0001] This application relates to the technical field of high pier bridge construction. Specifically, it relates to a variable cross-section day-shaped open-web thin-wall pier steel bar structure and an installation method thereof. Background Technique

[0002] With the continuous development of the transportation industry, more and more bridges are being built in China, covering a wider and wider area. Ultra-high pier bridges across mountains and valleys are also increasing day by day. Although there are some design and construction studies on ultra-high pier bridges at home and abroad, there are still some problems in ultra-high pier construction: difficult linear control, time-consuming overall hoisting of steel bars, etc.

[0003] In the prior art, the main piers of ultra-high pier bridges usually have a height of 159m, a constant width of 18.5m in the transverse direction of the bridge pier, and a slope widening ratio of 80:1 from the top of the pier of 8.0m to the bottom of the pier in the longitudinal direction of the bridge. Steel bar binding is a key process in pier construction. The number of main steel bars in the standard cross-section of the pier body exceeds 1200. The time for scattered splicing of steel bars is as long as 3 days, and the construction efficiency is low. At present, there is an existing method for overall hoisting of steel bars, which is applicable to the overall hoisting of steel bars for small cross-section pier bodies. 1) The weight of a single-section steel bar in this project is 70t, and the equipment requirements for overall hoisting are high, and the hoisting risk is large; 2) The cross-sectional size is large, and the steel bar skeleton is prone to deformation during the hoisting process, resulting in difficult butt joint.

[0004] For ultra-high pier construction, its overall weight is large, the equipment requirements for hoisting are high, the hoisting risk is large, and the cross-sectional size is large. The steel bar skeleton is prone to deformation during the hoisting process, resulting in difficult butt joint and affecting the construction efficiency. Summary of the Invention

[0005] The main purpose of this application is to provide a variable cross-section day-shaped open-web thin-wall pier steel bar sectional prefabrication jig and a sectional installation method, so as to solve the problems of difficult hoisting, difficult butt joint, and affecting construction efficiency in the related art for ultra-high pier construction.

[0006] To achieve the above purpose, this application provides a variable cross-section day-shaped open-web thin-wall pier steel bar sectional prefabrication jig, including:

[0007] A jig assembly, the jig assembly is divided into an I-shaped jig and two concave-shaped jigs. The jig assembly includes a number of columns, a number of first I-beams, a number of binding platforms, and a number of crossbeams. The lower parts of the number of columns are connected by the number of first I-beams. The number of binding platforms is installed between two adjacent columns, and the number of crossbeams is installed between the number of columns;

[0008] A stiffening skeleton, the stiffening skeleton includes a number of vertical rods and a number of second I-beams. The number of second I-beams are connected between two adjacent vertical rods. The number of second I-beams are respectively connected to the number of crossbeams through main steel bars.

[0009] In one embodiment of the present invention, a plurality of the columns are provided with supporting bridges at their lower parts, and supporting legs are provided at their lower parts.

[0010] In one embodiment of the present invention, the supporting trestle includes a third I-beam and several first channel steels, the lower part of the third I-beam is provided with a bracket, the supporting legs are installed at the lower part of the bracket, several first channel steels are installed at the upper part of the third I-beam, the columns are installed at the upper part of the first channel steels, and the sides of the first channel steels and the sides of the columns are connected with stiffened plates.

[0011] In one embodiment of the present invention, the first I-beam is located at the upper part of the first channel steels, and a fall prevention net is installed on the side of the first I-beam.

[0012] In one embodiment of the present invention, the tying platform includes a second channel steel, a first corbel plate, a second corbel plate and a wooden board, the first corbel plate is installed on the side of the second channel steel, the side of the first corbel plate is connected to the column, the wooden board is installed on the upper part of the second channel steel, and the lower part of the wooden board is connected to the column through the second corbel plate.

[0013] In one embodiment of the present invention, a tripod is connected between the lower side of the second channel steel and the side of the column.

[0014] In one embodiment of the present invention, the first corbel plate includes a first connecting plate and two first side plates, the two first side plates are symmetrically installed on the lower wall of the first connecting plate, the cross-section of the first side plate is trapezoidal, and the sides of the first connecting plate and the two first side plates are both provided with first notches that cooperate with the columns.

[0015] In one embodiment of the present invention, the second corbel plate includes a second connecting plate and two second side plates, the two second side plates are symmetrically installed on the side walls of the second connecting plate, the cross-section of the second side plate is rectangular, and the sides of the second connecting plate and the two second side plates are both provided with second notches that cooperate with the columns.

[0016] In one embodiment of the present invention, the overall cross-section of the rigid frame matches the overall cross-section of the tire frame assembly.

[0017] In an embodiment of the present invention, diagonal braces are connected between the plurality of columns and the side walls of the plurality of second I-beams.

[0018] The present application also provides a partition installation method for a variable-section Japanese-shaped hollow thin-walled pier steel bar partition prefabricated tire frame, comprising the following steps:

[0019] S1: Prefabrication by Zones. Divide the standard-section steel bars into 2 "[-]" shaped block segments and 1 "I-" shaped block segment. Except for leaving a 30 - 40 cm gap between the block segments to prevent the steel bars from colliding, the rest of the main steel bars are prefabricated in advance. The steel bar segments are prefabricated by zones on the jig near the pier shaft. The prefabricated parts include all the main steel bars within the stiffening skeleton area and all the stirrups within a height of 4 - 4.5 m. Horizontal separating steel bars are arranged between the double-leg main steel bars and are connected to the skeleton through pick-off steel bars.

[0020] S2: Erection of Lifting Ears. The steel bar segments are lifted by 4 points. The lifting ears are processed from 1 - 3 cm thick steel plates and are arranged on the top chord bracing of the stiffening skeleton. The lifting center of the segment is as close as possible to the center of gravity of the segment to ensure balanced lifting. The bracing connected to the lifting ears is replaced from angle steel to double-leg angle steel. In addition, two force-transferring angle steels are welded on the lifting ears, and the bottom of the force-transferring angle steels is welded on the columns of the stiffening skeleton to meet the stress requirements at the lifting points.

[0021] S3: Lifting of Segments. Before removing the sleeves, mark every 1 m to prevent misalignment when the main steel bars are butt-jointed again during installation on the pier. Remove the connection between the reference segment and the secondary segment of the steel bar. First, remove the connection of the steel bar sleeves, then disconnect the connection of the stiffening skeleton, and check whether there are other constraints not released to prevent omission of connection removal.

[0022] S4: Guidance. The guiding device is planned to adopt the form of inner and outer steel sleeves. Vertical guiding steel pipes are set at the contact surface between the reference segment and the secondary segment of the steel bars. The height of the guiding steel sleeves is 1 - 1.5 m, and one is set at each corner point, and 4 guiding steel sleeves are set for each block of the skeleton.

[0023] S5: Butt-Joint of Segment Steel Bars. Since the stiffening skeleton is inevitably slightly deformed after lifting, which will cause a slight change in the spatial position of the main steel bars before and after lifting. During butt-joint, the principle of "butt-joint while lowering and butt-joint the first-contact ones first" should be followed. When some of the main steel bars cannot be butt-jointed locally during the lowering process, they can be temporarily not butt-jointed. After the main steel bars of the large area are butt-jointed and the stiffening skeleton is connected and fixed, then deal with the remaining unbutt-jointed main steel bars.

[0024] S6: Installation of the Remaining Steel Bars. After the butt-joint of the prefabricated block steel bars is completed, install the main steel bars at the 32 - 38 cm gap between the blocks, then install the horizontal stirrups and tie bars at 0 - 1.7 m above the concrete surface and at the 32 - 36 cm gap. Release the hook of the tower crane and install the steel bars of another block.

[0025] In an embodiment of the present invention, in step S2, since the pier shaft has a variable cross-section structure, an adjustable special lifting tool is adopted. The upper part of the lifting tool is two double-leg slings. The beam body uses an H-shaped steel of 340x250x14x9. There are four groups of lifting points at the lower part. A number of bolt holes are provided on the lifting tool at each group of lifting point positions. Different bolt holes are selected according to the cross-section size to ensure that the lifting point coincides with the projection of the center of gravity of the skeleton. The height of the lifting point can be adjusted by a chain block under the lifting point to adjust the attitude of the skeleton.

[0026] In an embodiment of the present invention, in step S3, the lifting must be carried out in stages and slowly. After lifting the bright seam, pause, measure the distance between the upper and lower steel bar joints and the height difference of the four points of the stiffening skeleton, and appropriately adjust through the lifting tool to make the projection of the lifting point and the center of gravity coincide on the ground as much as possible; remove all the load-bearing cantilever beams of this section to make the section suspended; after adjusting the position of the center of gravity, continue to lift slowly until it is completely separated from the jig.

[0027] In an embodiment of the present invention, in step S4, control the speed of the tower crane trolley according to the theoretical distance between the lifting point and the placement point. When the steel bar section is lifted above the projection plane, pause and stand still first. After the steel bar section is stable, lower it slowly; when the section is lowered to 10 cm away from the steel bar lap joint, pause, align the guide pipe, and continue to lower it using the guide pipe for positioning; when the steel reinforcement cage touches, immediately align the marked reference steel bars for connection, and at the same time connect and fix the stiffening skeletons at the four corner points, and start connecting the remaining steel bar joints.

[0028] In an embodiment of the present invention, in step S5, in order to prevent the situation that when a small part of the steel bar joints are connected, there is no way to connect in place or the gap between the steel bar ends is too large, the following methods are used for treatment: a Purchase extrusion connection cone sleeve joints in advance, and use the "cone sleeve joint extrusion pliers" to extrude each connection cone sleeve joint to complete the steel bar connection; b Use the side bar welding for welding, and the welding shall meet the specification requirements; c Remove some of the main steel bars with larger gaps, re-align them, and make marks and adjustments during the processing of the next section.

[0029] In an embodiment of the present application, a variable cross-section day-shaped hollow thin-wall pier steel bar partition prefabrication jig is provided. It is connected by several columns, several first I-beams, several binding platforms and several cross beams to form independent blocks, and the overall cross-section of the independent blocks is in the shape of an I and a concave shape, forming an I-shaped jig and two concave-shaped jigs. The connection of the I-shaped jig and the concave-shaped jigs forms a day-shaped jig assembly; then connect several vertical rods and several second I-beams to form a stiffening skeleton that cooperates with the jig assembly. The overall cross-section of the stiffening skeleton cooperates with the I-shaped jig and the concave-shaped jigs. Stack and assemble several I-shaped jigs, two concave-shaped jigs and several stiffening skeletons in sequence to complete the assembly of the high pier. Since it is assembled in a segmented form, the weight of each part is reduced, which is convenient for hoisting, and the cross-sectional dimensions of each part are small, which is convenient for splicing. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The drawings constituting a part of this application are used to provide a further understanding of this application, making other features, purposes and advantages of this application more obvious. The schematic embodiments and descriptions of the drawings of this application are used to explain this application and do not constitute an improper limitation of this application. In the drawings:

[0031] Figure 1 It is a top view schematic diagram of a variable cross-section day-shaped hollow thin-wall pier steel bar structure provided according to an embodiment of the present application;

[0032] Figure 2 It is a Figure 1 Schematic cross-sectional view of the formwork component at A-A in

[0033] Figure 3 It is a Figure 1 Schematic cross-sectional view of the formwork component at B-B in the variable cross-section day-shaped hollow thin-wall pier steel bar structure provided according to an embodiment of the present application;

[0034] Figure 4 It is a Figure 1 Schematic cross-sectional view of the formwork component and stiffening skeleton at D-D in the variable cross-section day-shaped hollow thin-wall pier steel bar structure provided according to an embodiment of the present application;

[0035] Figure 5 It is a Figure 1 Schematic cross-sectional view at C-C and D-D in the variable cross-section day-shaped hollow thin-wall pier steel bar structure provided according to an embodiment of the present application;

[0036] Figure 6 It is a Figure 4 Schematic cross-sectional view at E in the variable cross-section day-shaped hollow thin-wall pier steel bar structure provided according to an embodiment of the present application;

[0037] Figure 7 It is a Figure 5 Schematic cross-sectional view at F in the variable cross-section day-shaped hollow thin-wall pier steel bar structure provided according to an embodiment of the present application;

[0038] Figure 8 It is a first perspective view schematic diagram of the first horn plate of the variable cross-section day-shaped hollow thin-wall pier steel bar structure provided according to an embodiment of the present application;

[0039] Fig. 9 It is a second perspective view schematic diagram of the first horn plate of the variable cross-section day-shaped hollow thin-wall pier steel bar structure provided according to an embodiment of the present application;

[0040] Fig.10 It is a third perspective view schematic diagram of the first horn plate of the variable cross-section day-shaped hollow thin-wall pier steel bar structure provided according to an embodiment of the present application;

[0041] Fig.11 It is a first perspective view schematic diagram of the second horn plate of the variable cross-section day-shaped hollow thin-wall pier steel bar structure provided according to an embodiment of the present application;

[0042] Fig.12It is a schematic diagram of a second angle plate of a variable-section Japanese-shaped hollow thin-walled pier steel bar structure according to a second viewing angle of the embodiment of the present application;

[0043] Fig.13 It is a third perspective schematic diagram of a second horn plate of a variable-section Japanese-shaped hollow thin-walled pier steel bar structure provided in an embodiment of the present application;

[0044] Fig.14 The variable-section Japanese-shaped hollow thin-walled pier steel bar structure provided in the embodiment of the present application is Figure 1 Schematic diagram of the rigid skeleton cross section at AA.

[0045] In the figure: 100, tire frame assembly; 110, I-shaped tire frame; 120, concave tire frame; 130, column; 140, first I-beam; 141, anti-fall net; 150, lashing platform; 151, second channel steel; 152, first corbel; 1521, first connecting plate; 1522, first side plate; 1523, first notch; 153, second corbel; 1531, second connecting plate; 1532, second side plate; 1533, second notch; 154, wooden board; 155, tripod; 160, shoulder pole beam; 170, supporting trestle; 171, third I-beam; 172, first channel steel; 173, bracket; 174, stiffened plate; 180, supporting leg; 200, rigid frame; 210, pole; 220, second I-beam; 221, diagonal brace; 230, main reinforcement. DETAILED DESCRIPTION

[0046] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present application.

[0047] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present application described here. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0048] In the present application, the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inner", "outer", "middle", "vertical", "horizontal", "lateral", "longitudinal" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings. These terms are mainly used to better describe the present application and its embodiments, and are not used to limit the indicated devices, elements or components to have a specific orientation, or to be constructed and operated in a specific orientation.

[0049] In addition, some of the above terms may be used to express other meanings in addition to indicating orientation or positional relationship. For example, the term "on" may also be used to express a certain dependency or connection relationship in some cases. For those of ordinary skill in the art, the specific meanings of these terms in this application can be understood according to specific circumstances.

[0050] In addition, the term "plurality" shall mean two or more.

[0051] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0052] Example 1

[0053] See also Figure 1-14 The present application provides a variable-section, Japanese-shaped hollow thin-walled pier steel bar partition prefabricated tire frame, including a tire frame assembly 100 and a rigid frame 200, and the rigid frame 200 is connected to the side of the tire frame assembly 100.

[0054] See also Figure 1-13 The overall cross-section of the tire frame assembly 100 is arranged in a Japanese shape. The tire frame assembly 100 is divided into an I-shaped tire frame 110 and two concave tire frames 120. The tire frame assembly 100 includes a plurality of columns 130, a plurality of first I-beams 140, a plurality of tying platforms 150 and a plurality of shoulder pole beams 160. The lower parts of the plurality of columns 130 are connected by a plurality of first I-beams 140. The columns 130 are arranged as steel pipes. The plurality of tying platforms 150 are installed between two adjacent columns 130 by bolts. The plurality of shoulder pole beams 160 are installed between the plurality of columns 130 by bolts. The shoulder pole beams 160 are arranged as channel steels.

[0055] In this embodiment, a supporting trestle 170 is installed at the lower part of the plurality of columns 130, and a supporting leg 180 is installed at the lower part of the supporting trestle 170. In the specific setting, the supporting trestle 170 includes a third I-beam 171 and a plurality of first channel steels 172, a bracket 173 is welded at the lower part of the third I-beam 171, and the supporting leg 180 is welded and installed at the lower part of the bracket 173, and a plurality of first channel steels 172 are welded and installed at the upper part of the third I-beam 171, and the column 130 is installed at the upper part of the first channel steel 172, and the side of the first channel steel 172 and the side of the column 130 are connected with a stiffening plate 174. Specifically, the first I-beam 140 is located at the upper part of the plurality of first channel steels 172, and a falling prevention net 141 is installed at the side of the first I-beam 140, and the falling prevention net 141 is used to prevent falling and protect the operating workers.

[0056] In this embodiment, the tying platform 150 includes a second channel steel 151, a first corbel plate 152, a second corbel plate 153 and a wooden board 154. The first corbel plate 152 is installed on the side of the second channel steel 151, and the side of the first corbel plate 152 is connected to the column 130. When specifically set, the lower side of the second channel steel 151 and the side of the column 130 are connected with a tripod 155. The wooden board 154 is laid and installed on the upper part of the second channel steel 151, and the lower part of the wooden board 154 is connected to the column 130 through the second corbel plate 153. Specifically, the first corbel plate 152 includes a first connecting plate 1521 and two first side plates 1522. The two first side plates 1522 are symmetrically installed on the lower wall of the first connecting plate 1521. The cross-section of the first side plate 1522 is trapezoidal. The first connecting plate 1521 and The sides of the two first side panels 1522 are each provided with a first notch 1523 that cooperates with the column 130. The first notch 1523 facilitates the effective connection between the first side panel 1522 and the first connecting plate 1521, and facilitates the support and fixation of the second channel steel 151. Specifically, the second corbel plate 153 includes a second connecting plate 1531 and two second side panels 1532. The two second side panels 1532 are symmetrically installed on the side walls of the second connecting plate 1531. The cross-section of the second side panel 1532 is rectangular. The sides of the second connecting plate 1531 and the two second side panels 1532 are each provided with a second notch 1533 that cooperates with the column 130. The second notch 1533 facilitates the effective connection between the second side panel 1532 and the second connecting plate 1531, and facilitates the support and fixation of the second channel steel 151.

[0057] See also Figure 1 , Figure 4 , Figure 5 and Fig.14, the overall cross-section of the stiffening skeleton 200 is matched with the overall cross-section of the formwork support assembly 100. The stiffening skeleton 200 includes a number of vertical rods 210 and a number of second I-beams 220. Between every two adjacent vertical rods 210, they are connected by the second I-beams 220. Specifically, when setting, diagonal braces 221 are connected between the side walls of a number of columns 130 and a number of second I-beams 220. The diagonal braces 221 increase the connection strength. A number of second I-beams 220 are respectively connected to a number of cross beams 160 through main reinforcement bars 230.

[0058] Specifically, the working principle of the variable cross-section I-shaped open-web thin-wall pier steel bar structure: When in use, a number of columns 130, a number of first I-beams 140, a number of tying platforms 150 and a number of cross beams 160 are connected to form an independent block section, and the overall cross-section of the independent block section is in the shape of I and concave, forming an I-shaped formwork support 110 and two concave formwork supports 120. The connection of the I-shaped formwork support 110 and the concave formwork supports 120 forms an I-shaped formwork support assembly 100; then a number of vertical rods 210 and a number of second I-beams 220 are connected to form a stiffening skeleton 200 that matches the formwork support assembly 100. The overall cross-section of the stiffening skeleton 200 is matched with the I-shaped formwork support 110 and the concave formwork supports 120. Stacking and assembling a number of I-shaped formwork supports 110, two concave formwork supports 120 and a number of stiffening skeletons 200 in sequence can complete the assembly of the high pier. Due to the form of segmental assembly, the weight of each part is reduced, which is convenient for hoisting, and the cross-sectional dimensions of each part are small, which is convenient for splicing.

[0059] The present application also provides a partition installation method for a partition prefabricated formwork support of a variable cross-section I-shaped open-web thin-wall pier, including the following steps:

[0060] S1: Partition prefabrication. Divide the standard cross-section steel bars into 2 "[-]" shaped block sections and 1 "I" shaped block section. Except for leaving 35 cm between the block sections to prevent the collision of steel bars, the rest of the main reinforcement bars are prefabricated in advance; the steel bar sections are prefabricated in partitions on the formwork support near the pier body. The prefabricated part includes all the main reinforcement bars in the stiffening skeleton area and all the stirrups within a height of 4.2 m (excluding the joints staggered by 1.3 m and the part exposed 0.5 m above the concrete surface). Horizontal separating reinforcement bars are arranged in the middle of the double-limb main reinforcement bars and are connected to the skeleton through pick-up reinforcement bars.

[0061] S2: Hoisting ear installation. The steel bar sections are lifted by 4 points. The hoisting ears are processed with 2 cm thick steel plates. The hoisting ears are arranged on the top horizontal connection of the stiffening skeleton. The hoisting center of the section is as close as possible to the center of gravity of the section to ensure balanced hoisting. The horizontal connection welded to the hoisting ears is replaced from an angle steel to a double-limb angle steel. In addition, two force-transferring angle steels are welded on the hoisting ears. The bottom of the force-transferring angle steels is welded on the columns of the stiffening skeleton to meet the force requirements at the hoisting points.

[0062] Since the pier body is a variable-section structure, an adjustable special hoist is used. The upper part of the hoist is two double-leg riggings, the beam body is made of 340x250x14x9 H-shaped steel, and the lower part has four sets of lifting points. Each set of lifting points is provided with several bolt holes on the hoist. Different bolt holes are selected according to the cross-sectional size to ensure that the lifting point coincides with the projection of the center of gravity of the skeleton; the hand chain hoist can be used to adjust the height of the lifting point and the posture of the skeleton under the lifting point.

[0063] S3: Segment lifting. Before removing the sleeve, mark every 1m to prevent the main reinforcement from being connected incorrectly when it is installed on the pier; to remove the connection between the reference section and the secondary steel bar segment, first remove the steel bar sleeve connection, then disconnect the rigid skeleton connection, and check whether there are other constraints that have not been released to prevent the connection from being missed;

[0064] The lifting must be done in stages and slowly. Pause after the lifting seams are exposed, carefully observe the aerial posture of the segment, measure the spacing between the upper and lower steel bar joints, and the height difference of the four points of the rigid skeleton, and make appropriate adjustments through the lifting equipment to make the lifting point coincide with the projection of the center of gravity on the ground as much as possible; remove all the load-bearing beams of this segment to make the segment suspended in the air; after adjusting the center of gravity, continue to lift slowly until it is completely separated from the frame.

[0065] S4: Guidance. The guiding device is planned to adopt the form of internal and external steel casings. Vertical guiding steel casings are set at the contact surface of the base section and the secondary section steel bars. The height of the guiding steel casing is about 1.2m. One is set at each corner point, and 4 guiding steel casings are set for each segment skeleton.

[0066] Control the speed of the tower crane trolley according to the theoretical distance between the lifting point and the placement point. When the steel segment is lifted above the projection surface, pause and let it stand, and then slowly lower it after the steel segment is stable (adjustment with human assistance); pause when the segment is lowered to 10 cm away from the steel overlap, align the guide tube, and continue to lower it using the guide tube for positioning; when the steel cage contacts, immediately align the marked reference steel bars and connect them, and at the same time connect and fix the rigid skeletons at the four corner points, and start connecting the remaining steel joints.

[0067] S5: Segmental reinforcement butt joint. Because the rigid skeleton will inevitably deform slightly after lifting, the spatial position of the main reinforcement will change slightly before and after lifting. The butt joint should follow the principle of "butt joint while lowering, first contact first butt joint". If some local main reinforcements cannot be butt jointed during the lowering process, they can be temporarily not butt jointed. After the large-area main reinforcement is butt jointed and the rigid skeleton is connected and fixed, the remaining main reinforcements that are not butt jointed can be processed;

[0068] In order to prevent the situation that a small part of the steel bar joints cannot be connected in position or the gap between the steel bar ends is too large due to the lack of tightening, the following methods are used to deal with it:

[0069] a. Purchase the extrusion connection cone sleeve joints in advance, and use the "cone sleeve joint extrusion pliers" to extrude the cone sleeve joints one by one to complete the steel bar connection.

[0070] b. Use auxiliary rod welding for welding, and the welding must comply with the requirements of the specifications.

[0071] c. Remove the main reinforcement with larger gaps, re-join them, and mark and adjust them during the next processing.

[0072] S6: Install the remaining reinforcement

[0073] After the prefabricated block segments are butt-jointed, the main reinforcement is installed at the 35cm gap between the blocks, and then the horizontal stirrups and tension reinforcement are installed within 1.7m and at the 35cm gap on the concrete surface. The tower crane is unhooked to install the reinforcement of another block segment.

[0074] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for sectional installation of a sectional variable cross-section day-shaped hollow thin-wall pier steel bar prefabrication jig The sectional variable cross-section day-shaped hollow thin-wall pier steel bar prefabrication jig includes: A jig assembly, which is divided into an I-shaped jig and two concave jigs. The jig assembly includes several columns, several first I-beams, several binding platforms and several cross beams. The lower parts of several columns are connected by several first I-beams. Several binding platforms are installed between two adjacent columns, and several cross beams are installed between several columns; A stiffening skeleton, which includes several vertical rods and several second I-beams. Several adjacent two vertical rods are connected by second I-beams, and several second I-beams are respectively connected to several cross beams through main steel bars; Support trestles are installed at the lower parts of several columns, and legs are installed at the lower parts of the support trestles; The support trestle includes a third I-beam and several first channel steels. There are brackets at the lower part of the third I-beam. The legs are installed at the lower parts of the brackets. Several first channel steels are installed on the upper part of the third I-beam. The columns are installed on the upper part of the first channel steels. Reinforcing plates are connected between the side parts of the first channel steels and the side parts of the columns; The first I-beam is located above several first channel steels, and a safety net against falling is installed on the side part of the first I-beam; The binding platform includes a second channel steel, a first bracket plate, a second bracket plate and a wooden board. The first bracket plate is installed on the side part of the second channel steel. The side part of the first bracket plate is connected to the column. The wooden board is installed on the upper part of the second channel steel. The lower side of the wooden board is connected to the column through the second bracket plate; characterized in that The sectional installation method includes the following steps: S1: Sectional prefabrication. Divide the standard cross-section steel bars into 2 "[“-shaped block segments and 1 "I”-shaped block segment. Except for leaving 30-40 cm between block segments to prevent steel bar collision, the rest of the main steel bars are prefabricated in advance; the steel bar segments are prefabricated sectionally on the jig near the pier body. The prefabricated part includes all the main steel bars within the stiffening skeleton area and all the stirrups within a height of 4-4.5 m. Horizontal separating steel bars are arranged between the double-leg main steel bars and are connected to the skeleton through pick-up steel bars; S2: Hoisting ear installation. The steel bar segments are hoisted by 4 points. The hoisting ears are processed with 1-3 cm steel plates. The hoisting ears are arranged on the top horizontal connection of the stiffening skeleton. The hoisting center of the segment is as close as possible to the center of gravity of the segment to ensure hoisting balance. The horizontal connection welded to the hoisting ear is replaced from an angle steel to a double-leg angle steel. In addition, two force-transferring angle steels are welded on the hoisting ear. The bottom of the force-transferring angle steel is welded to the column of the stiffening skeleton to meet the force requirements at the hoisting point; S3: Segment hoisting. Mark every 1 m before removing the sleeve to prevent misconnection when the main steel bars are butt-jointed again during installation on the pier; Remove the connection between the reference segment and the secondary segment of the steel bar segment. First, remove the connection of the steel bar sleeve, then disconnect the connection of the stiffening skeleton, and check whether there are other constraints not released to prevent omission of connection removal; S4: Guide. The guide device is planned to adopt the form of internal and external steel casings. Vertical guide steel casings are set at the contact surface of the reference section and the secondary section steel bars. The guide steel casing is 1-1.5m high, one is set at each corner point, and 4 guide steel casings are set for each segment skeleton. S5: Segmental reinforcement butt joint. Because the rigid skeleton will inevitably deform slightly after lifting, the spatial position of the main reinforcement will change slightly before and after lifting. The butt joint should follow the principle of "butt joint while lowering, first contact first butt joint". If some local main reinforcements cannot be butt jointed during the lowering process, they can be temporarily not butt jointed. After the large-area main reinforcement is butt jointed and the rigid skeleton is connected and fixed, the remaining main reinforcements that are not butt jointed can be processed; S6: Install the remaining steel bars. After the prefabricated block segments are connected, install the main bars at the 32-38cm gap between the blocks, and then install the horizontal stirrups and tension bars at the 0-1.7m and 32-36cm gaps on the concrete surface. Unhook the tower crane and install the steel bars of another block segment.

2. The sectional installation method of the sectional prefabrication jig for the variable-section day-shaped hollow thin-wall pier steel bars according to claim 1, characterized in that, In step S2, since the pier body is a variable-section structure, an adjustable special sling is used. The upper part of the sling is two double-leg riggings, the beam body is made of 340x250x14x9 H-shaped steel, and there are four groups of sling points at the bottom. Each group of sling points is provided with a number of bolt holes on the sling. Different bolt holes are selected according to the cross-sectional size to ensure that the lifting point coincides with the projection of the center of gravity of the skeleton; the hand winch can be used to adjust the height of the sling point and the posture of the skeleton under the sling point.

3. The sectional installation method of the sectional precast formwork for the variable-section H-shaped thin-walled pier steel bars as claimed in claim 1, wherein The lifting must be done in stages and slowly. Pause after the lifting seams are exposed, measure the spacing between the upper and lower steel bar joints, and the height difference of the four points of the rigid frame, and make appropriate adjustments through the lifting equipment to make the lifting point coincide with the projection of the center of gravity on the ground as much as possible; remove all the load-bearing beams of this section to make the section suspended in the air; after adjusting the center of gravity position, continue to lift slowly until it is completely separated from the frame.

4. The sectional installation method of the sectional prefabrication jig for the variable-section daily-shaped hollow thin-wall pier steel bars according to claim 1, characterized in that In step S4, the speed of the tower crane trolley is controlled according to the theoretical distance between the lifting point and the placement point. When the steel segment is lifted above the projection surface, it is first paused and left to stand still, and then slowly lowered after the steel segment is stable; when the segment is lowered to 10 cm away from the steel overlap, it is paused, the guide tube is aligned, and the guide tube is used to position and continue to be lowered; when the steel cage contacts, the marked reference steel bars are immediately aligned and connected, and at the same time, the rigid skeletons of the four corner points are connected and fixed, and the connection of the remaining steel joints begins.

5. The sectional installation method of a sectional variable cross-section day-shaped hollow thin-wall pier steel bar partition prefabrication jig as claimed in claim 1, wherein In step S5, in order to prevent the situation that a small part of the steel bar joints cannot be connected in position or the steel bar ends are not tightened and the gap is too large, the following methods are used: a. Purchase the extrusion connection cone sleeve joints in advance, and use "cone sleeve joint extrusion pliers" to extrude the cone sleeve joints one by one to complete the steel bar connection; b. Use auxiliary bar welding for welding, and the welding must meet the requirements of the specifications; c. Remove the main bars with larger gaps, re-join them, and mark and adjust them in the next processing.

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