Shallow water steel hanging box construction method

Abstract

According to the shallow water steel hanging box construction method, the anchoring position of the finish rolling deformed steel bar hanging rod is changed, so that the finish rolling deformed steel bar hanging rod provides additional hanging force, buoyancy lacking due to the fact that the water entry depth of a bearing platform is small is made up, bottom sealing concrete pouring is carried out twice, and the construction efficiency is improved. According to the method, the traditional mode that the dead weight of the anti-bearing platform concrete is increased by increasing the thickness of the bottom sealing concrete to increase the bond stress is changed, the investment of the construction cost is greatly saved, and the whole construction process is rapid and safe.

Description

Technical Field

[0001] The invention relates to the technical field of bridge construction, in particular to a shallow water steel hanging box construction method. Background Art

[0002] At present, in cross-river bridges with large water depths, high pile caps are a common structural form. Their construction method is generally the more mature casing method. During the implementation of this construction method, an underwater dry working environment is created and then the high pile caps are cast in place in layers. The process principle is to use the deadweight and bond strength of the bottom concrete to resist the buoyancy of water under pumping conditions; and to use the buoyancy of water and the bond strength of the bottom concrete to resist the deadweight of the cap concrete under the cap concrete pouring conditions. This method has been used in my country for many years and has been proven to be suitable for the construction of high pile caps. However, for high pile caps with shallow water depth, due to insufficient buoyancy of water, the sum of the bond strength of water and the bottom concrete cannot balance the deadweight of the cap concrete. Increasing the thickness of the bottom concrete to improve the bond strength will greatly increase the investment in construction costs, and the bottom concrete also has its own weight to be balanced. Increasing the thickness does not significantly improve the bond strength, which is obviously not suitable in terms of social and economic benefits.

[0003] The object of the present invention is to provide a shallow water steel hanging box construction method to solve the problems mentioned in the above background technology. Summary of the invention

[0004] To achieve the above object, the present invention provides a shallow water steel hanging box construction method, comprising the following steps:

[0005] S1. Set up an assembly platform. A steel bracket is welded on one side of each steel casing. A plurality of steel brackets constitute an above-water assembly platform for a steel hanging box. The actual position of the steel casing and the designed position of the crossbeam position of the steel hanging box are measured and laid out.

[0006] S2, assembling the steel hanging box, installing the bottom plate of the steel hanging box on the erected assembly platform, the top of the bottom plate is provided with a enclosure and a support system, the enclosure is arranged along the top surface of the bottom plate, and the support system is installed on the inner side of the enclosure;

[0007] S3, installing a suspension system on the steel casing, the suspension system is used to lower the steel hanging box, the suspension system includes a suspension hanger, a through-hole jack, and a fine-rolled threaded steel hanger rod, the suspension hanger is installed on the top of the steel casing, and the fine-rolled threaded steel hanger rods are arranged on both sides of each steel casing, the fine-rolled threaded steel hanger rods pass through the suspension hanger and are connected to the bottom plate, the through-hole jack passes through the top of the fine-rolled threaded steel hanger rod and is installed on the top of the suspension hanger;

[0008] S4. After the suspension system is installed, the steel hanging box is lowered to the designed elevation by using the through-hole jack, and then the first floor bottom concrete is poured;

[0009] S5. After the first-layer bottom concrete has no leakage and reaches the designed strength, water is pumped out in the steel hanging box to form a dry working environment. Then, suspension brackets are symmetrically welded on the fine-rolled threaded steel hangers on both sides of each steel casing. The suspension brackets are located above the first-layer bottom concrete. Then, the anchoring positions of the fine-rolled threaded steel hangers are replaced one by one from the top of the steel casing to the suspension brackets.

[0010] S6. After the anchoring position of the fine-rolled threaded steel hanger is changed, the second layer of bottom sealing concrete is poured in a dry working environment and the surface is smoothed.

[0011] As a further improvement of the present invention, the enclosure includes a plurality of side panels, and the plurality of side panels are sequentially arranged around the top surface of the base plate. The support system includes a purlin and an inner support plate. The purlin and the inner support plate are installed on the inner side of each side panel, and the purlin is arranged between the inner support plate and the side panel.

[0012] As a further improvement of the present invention, a cross beam is connected to the bottom of the base plate. According to the layout points on the steel corbel, the cross beam is installed in sequence along the positions of the layout points. After the installation of the cross beam is completed, the base plate is installed on the cross beam. The bottom end of the fine-rolled threaded steel hanger passes through the base plate and extends out of the bottom of the cross beam and is locked and fixed by nut 1.

[0013] As a further improvement of the present invention, the fine-rolled threaded steel hanger includes a first hanger and a second hanger, the connection position of the first hanger and the second hanger is located 40 cm from the top surface of the first layer of bottom concrete, the first hanger and the second hanger are connected and fixed by a fine-rolled threaded steel connector, the first hanger is connected to the through-hole jack, the first layer of bottom concrete is poured at the position of the second hanger, and the bottom of the second hanger passes through the first layer of bottom concrete and the bottom plate and is anchored below the beam.

[0014] As a further improvement of the present invention, the pouring thickness of the second layer of bottom sealing concrete should cover the top surface of the suspension corbel and be located below the precision-rolled threaded steel connector until the anti-floating requirements are met.

[0015] As a further improvement of the present invention, in step S5, the suspension corbel is made of I-beam, and the I-beam close to the side of the steel casing is connected to the outer wall of the steel casing by a corner weld. A steel pad is installed on the top of the symmetrically arranged I-beam and is locked and fixed to the precision-rolled threaded steel hanger rod by nut 2.

[0016] As a further improvement of the present invention, the suspension system in step S3 also includes a suspension distribution beam, which is symmetrically installed on the top of the suspension hanger, and the through-hole jack is installed on the top of the suspension distribution beam.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] The present invention converts the anchoring position of the fine-rolled threaded steel hanger in the suspension system so that the fine-rolled threaded steel hanger provides additional suspension force, thereby compensating for the lack of buoyancy due to the shallow water depth of the pedestal, and divides the pouring of the bottom sealing concrete into two times, thereby improving the reliability of the holding force of part of the bottom sealing concrete. This method changes the traditional way of increasing the holding force by increasing the thickness of the bottom sealing concrete to increase the deadweight of the pedestal concrete, greatly saving the investment in construction costs. The entire construction process is fast and safe, and is suitable for the construction of high-pile pedestals with a shallow water depth. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the installation of the suspension system before the steel hanging box is lowered;

[0020] Figure 2 It is a schematic diagram of the conversion of the suspension system after the steel hanging box of the present invention is lowered;

[0021] Figure 3 The present invention is attached Figure 2 Front view of the suspended corbel;

[0022] Figure 4 For the present invention Figure 3 Left view of the suspended corbel;

[0023] Figure 5 For the present invention Figure 3 Top view of the suspended corbel.

[0024] In the figure: 1. Steel casing; 2. Assembly platform; 3. Crossbeam; 4. Bottom plate; 5. Side plate; 6. Purlin; 7. Inner support plate; 8. Suspension hanger; 9. Suspension distribution beam; 10. Through-hole jack; 11. Finished rolled threaded steel hanger rod; 12. Finished rolled threaded steel connector; 13. Suspension corbel; 14. Steel pad; 15. Nut two; 16. First layer bottom seal concrete; 17. Second layer bottom seal concrete. DETAILED DESCRIPTION

[0025] To facilitate understanding of the present invention, the present invention will be described more comprehensively below with reference to the relevant drawings. Several embodiments of the present invention are given in the drawings, but the present invention can be implemented in different forms and is not limited to the embodiments described in the text. On the contrary, these embodiments are provided to make the content disclosed in the present invention more thorough and comprehensive.

[0026] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which the present invention belongs. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0027] The present invention is further described in detail below in conjunction with the accompanying drawings.

[0028] See also Figure 1-5 The present invention provides a shallow water steel hanging box construction method, comprising the following steps:

[0029] S1, set up the assembly platform 2, a steel bracket is welded on one side of each steel casing 1, and a plurality of the steel brackets constitute the steel hanging box water assembly platform 2, and measure and lay out according to the actual position of the steel casing 1 and the design position of the crossbeam 3 of the steel hanging box;

[0030] S2, assembling the steel hanging box, installing the bottom plate 4 of the steel hanging box on the erected assembly platform 2, the top of the bottom plate 4 is provided with a enclosure and a support system, the enclosure is arranged along the top surface of the bottom plate 4, and the support system is installed on the inner side of the enclosure;

[0031] S3, installing a suspension system on the steel casing 1, the suspension system is used to lower the steel hanging box, the suspension system includes a suspension hanger 8, a through-hole jack 10, and a fine-rolled threaded steel hanger rod 11, the suspension hanger 8 is installed on the top of the steel casing 1, and the fine-rolled threaded steel hanger rod 11 is provided on both sides of each steel casing 1, the fine-rolled threaded steel hanger rod 11 passes through the suspension hanger 8 and is connected to the base plate 4, the through-hole jack 10 passes through the top of the fine-rolled threaded steel hanger rod 11 and is installed on the top of the suspension hanger 8;

[0032] S4, after the suspension system is installed, the steel hanging box is lowered to the designed elevation by using the through-hole jack 10, and then the first floor bottom sealing concrete 16 is poured;

[0033] S5, after the first layer bottom seal concrete 16 has no leakage and reaches the design strength, water is pumped out in the steel hanging box to form a dry working environment, and then the suspension brackets 13 are symmetrically welded on the fine-rolled threaded steel hangers 11 on both sides of each steel casing 1, and the suspension brackets 13 are located above the first layer bottom seal concrete 16, and then the anchoring positions of the fine-rolled threaded steel hangers 11 are replaced one by one from the top of the steel casing 1 to the suspension brackets 13;

[0034] S6. After the anchoring position of the fine-rolled threaded steel hanger rod 11 is changed, the second layer of bottom sealing concrete 17 is poured in a dry working environment and the surface is smoothed.

[0035] The enclosure includes a plurality of side panels 5, which are sequentially arranged around the top surface of the bottom plate 4. The support system includes a purlin 6 and an inner support plate 7. The purlin 6 and the inner support plate 7 are installed on the inner side of each side panel 5. The purlin 6 is arranged between the inner support plate 7 and the side panel 5.

[0036] The bottom of the base plate 4 is connected to a crossbeam 3. According to the layout points on the steel corbel, the crossbeam 3 is installed in sequence along the positions of the layout points. After the installation of the crossbeam 3 is completed, the base plate 4 is installed on the crossbeam 3. The bottom end of the fine-rolled threaded steel hanger 11 passes through the base plate 4 and extends out of the bottom of the crossbeam 3 and is locked and fixed by a nut 15.

[0037] As a preferred embodiment, in step S1, the position of the cross beam 3 of the steel hanging box is pre-planned on the assembly platform 2 to facilitate the installation of the cross beam 3. In this embodiment, since the pile foundation construction allows a deviation within 5 cm, the layout position of the steel hanging box bottom plate 4 needs to be adjusted according to the actual pile center position measurement result, so that the reserved holes on the steel hanging box bottom plate 4 can be smoothly inserted into the casing, and the spacing on all sides is uniform.

[0038] As a preferred embodiment, in step S2, when installing the steel hanging box, after the installation of the bottom plate 4 and the cross beam 3 is completed, the side plates 5 are hoisted in blocks. During hoisting, the connecting bolts should be tightened synchronously and auxiliary supports should be used to prevent it from overturning. In order to improve the stability of the overall structure of the steel hanging box, the inner wall of the side plate 5 is respectively provided with a purlin 6 and an inner support plate 7 layer by layer to ensure its safety and reliability during the construction process. By installing the purlin 6 and the inner support plate 7 layer by layer, the load from the upper part can be effectively dispersed, the single-point force can be reduced, and the bearing capacity of the steel hanging box can be improved.

[0039] In particular, the suspension system in step S3 also includes a suspension distribution beam 9 , which is symmetrically installed on the top of the suspension hanger 8 , and the through-hole jack 10 is installed on the top of the suspension distribution beam 9 .

[0040] As a further embodiment, in step S3, a suspension distribution beam 9 is set on the top of the suspension hanger 8, which can evenly distribute the load from the through-hole jack 10 to the suspension beams on both sides, which ensures the balanced transfer of the load and prevents structural damage or failure caused by uneven load. By distributing the load to multiple suspension beams, the suspension distribution beam 9 helps to enhance the stability of the entire suspension system. As a part of the suspension system, the suspension distribution beam 9 provides a stable support platform for the through-hole jack 10, which ensures that the through-hole jack 10 can maintain a stable position during operation, thereby effectively transmitting force.

[0041] In this embodiment, when lowering the square steel hanging box, an array of through-hole jacks 10 controlled by an oil pump machine is used to gradually lower the corresponding high-quality rolled threaded steel hanging rod 11 in strokes, with a stroke of 10 to 15 cm, and gradually lower the steel hanging box to the designed elevation position. During the lowering process, attention should be paid to maintaining the overall flatness of the steel hanging box.

[0042] As a preferred embodiment, step S5 replaces the original anchoring position of the fine-rolled threaded steel hanger rod 11 from the suspension distribution beam 9 at the top of the steel casing 1 to the suspension corbel 13 one by one. By converting the anchoring point of the fine-rolled threaded steel hanger rod 11, the fine-rolled threaded steel hanger rod 11 provides additional suspension force, thereby compensating for the lack of buoyancy due to the shallow depth of the foundation into the water.

[0043] As a further embodiment, the fine-rolled threaded steel hanger 11 includes a first hanger and a second hanger, the connection position of the first hanger and the second hanger is located at 40 cm from the top surface of the first layer bottom concrete 16, the first hanger and the second hanger are connected and fixed by a fine-rolled threaded steel connector 12, the first hanger is connected to the through-hole jack 10, the first layer bottom concrete 16 is poured at the position of the second hanger, and the bottom of the second hanger passes through the first layer bottom concrete 16 and the bottom plate 4 and is anchored under the beam 3. After the steel hanging box is lowered, the number and arrangement of the conduits are determined according to the fluidity of the concrete and the thickness of the first layer bottom concrete 16 to be poured. When installing the pouring conduit, keep the bottom of the conduit at a suspended height of about 30 cm from the bottom plate 4 of the steel hanging box, and finally carry out underwater pouring of the first layer bottom concrete 16.

[0044] The pouring thickness of the second bottom sealing concrete 17 should cover the top surface of the suspension corbel 13 and be located below the finished rolled threaded steel connector 12 until the anti-floating requirement is met.

[0045] In this embodiment, the bottom sealing concrete is poured in two times. The first layer of bottom sealing concrete 16 is poured underwater, and its thickness should be able to meet the water-stopping effect and resist the buoyancy of water under the pumping condition in the steel hanging box. The second layer of bottom sealing concrete 17 is poured as a dry operation, and its thickness should meet the safety reserve of the holding force under the pouring condition of the foundation concrete and can cover the top surface of the system conversion suspension bracket 13. Among them, the fine-rolled threaded steel hanger 11 is divided into two sections, and it is necessary to ensure that the length of the second hanger meets the bottom nut installation requirements and the top can extend out of the top surface of the second layer of bottom sealing concrete 17. The length of the first hanger meets the requirements for lowering the steel hanging box. Furthermore, by dividing the fine-rolled threaded steel hanger 11 into two sections, the first hanger and the second hanger, the fine-rolled threaded steel hanger 11 can be more easily It can be transported to the construction site and is more flexible during installation. The setting of the joint position takes into account the convenience of construction, allowing construction personnel to fine-tune the length or position of the high-quality rolled threaded steel hanger rod 11 when necessary to adapt to specific construction conditions and needs. The joint position is set above the top surface of the first layer of bottom concrete, ensuring that during the concrete construction process, the high-quality rolled threaded steel hanger rod 11 can stably support the steel hanging box without affecting the pouring and curing of the concrete. By using the high-quality rolled threaded steel connector 12 to connect the two sections of the hanger, the firmness and stability of the joint position can be ensured, reducing the safety risks caused by the breakage or loosening of the hanger. The segmented design also helps to quickly remove or replace the hanger in an emergency to improve the safety of the construction site.

[0046] As a preferred embodiment, in step S5, the suspension corbel 13 is made of I-beam, and the I-beam close to the side of the steel casing 1 is connected to the outer wall of the steel casing 1 by a fillet weld, and a steel pad 14 is installed on the top of the symmetrically arranged I-beam and is locked and fixed to the precision-rolled threaded steel hanger rod 11 by a nut 15.

[0047] In this embodiment, the strength, rigidity, weld foot height and weld quality of the I-beam itself should meet the force requirements. The root of the suspension corbel 13 is reinforced with a triangular stiffening plate. During welding, electric welding should be prevented from touching the high-quality rolled threaded steel hanger rod 11. The I-beam is welded on both sides of the high-quality rolled threaded steel hanger rod 11, and the connection points between the high-quality rolled threaded steel hanger rod 11 and the steel casing 1 are increased, thereby improving the stability of the entire suspension system and improving safety. By replacing the anchor position to the suspension corbel 13, the load from the hanger rod can be more effectively dispersed and borne, reducing the safety risks caused by single-point force. The replacement of the anchor point of the high-quality rolled threaded steel hanger rod 11 should be carried out symmetrically one by one, and then the nut 15 is screwed into the high-quality rolled threaded steel hanger rod 11 for locking and fixing.

[0048] The above is an exemplary description of the present invention in combination with the accompanying drawings. It is obvious that the specific implementation of the present invention is not limited to the above-mentioned method. As long as such non-substantial improvements are made by adopting the method concept and technical solution of the present invention, or the concept and technical solution of the present invention are directly applied to other occasions without improvement, they are all within the protection scope of the present invention.

Claims

1. A shallow water steel hanging box construction method, characterized in that: The following steps are included: S1, setting up an assembly platform (2), welding a steel bracket on one side of each steel casing (1), a plurality of the steel brackets forming a steel hanging box water assembly platform (2), and measuring and setting out according to the actual position of the steel casing (1) and the designed position of the crossbeam (3) of the steel hanging box; S2, assembling the steel hanging box, installing the bottom plate (4) of the steel hanging box on the erected assembly platform (2), the top of the bottom plate (4) is provided with a enclosure and a support system, the enclosure is arranged along the top surface of the bottom plate (4), and the support system is installed on the inner side of the enclosure; S3. Install a suspension system on the steel casing (1), the suspension system is used to lower the steel hanging box, the suspension system comprises a suspension hanger (8), a through-hole jack (10), and a fine-rolled threaded steel hanger rod (11), the suspension hanger (8) is installed on the top of the steel casing (1), and the fine-rolled threaded steel hanger rod (11) is provided on both sides of each steel casing (1), the fine-rolled threaded steel hanger rod (11) passes through the suspension hanger (8) and is connected to the base plate (4), the through-hole jack (10) passes through the top of the fine-rolled threaded steel hanger rod (11) and is installed on the top of the suspension hanger (8); S4, after the installation of the suspension system is completed, the steel hanging box is lowered as a whole to the designed elevation position using the through-hole jack (10), and then the first floor bottom sealing concrete (16) is poured; S5, after the first layer bottom seal concrete (16) is leak-free and reaches the designed strength, water is pumped out in the steel hanging box to form a dry working environment, and then the suspension brackets (13) are symmetrically welded on the fine-rolled threaded steel hangers (11) on both sides of each steel casing (1), and the suspension brackets (13) are located above the first layer bottom seal concrete (16), and then the anchoring positions of the fine-rolled threaded steel hangers (11) are replaced one by one from the top of the steel casing (1) to the suspension brackets (13); S6. After the anchoring position of the fine-rolled threaded steel suspender rod (11) is changed, the second layer of bottom sealing concrete (17) is poured in a dry working environment and the surface is smoothed.

2. A shallow water steel hanging box construction method according to claim 1, characterized in that: The enclosure comprises a plurality of side panels (5), and the plurality of side panels (5) are sequentially arranged around the top surface of the base plate (4); the support system comprises a purlin (6) and an inner support plate (7); the purlin (6) and the inner support plate (7) are installed on the inner side of each side panel (5); the purlin (6) is arranged between the inner support plate (7) and the side panel (5).

3. A shallow water steel hanging box construction method according to claim 1, characterized in that: The bottom of the base plate (4) is connected to a crossbeam (3). According to the layout points on the steel bracket, the crossbeam (3) is installed in sequence along the positions of the layout points. After the crossbeam (3) is installed, the base plate (4) is installed on the crossbeam (3). The bottom end of the precision-rolled threaded steel hanger rod (11) passes through the base plate (4) and extends out of the bottom of the crossbeam (3) and is locked and fixed by a nut.

4. A shallow water steel hanging box construction method according to claim 3, characterized in that: The fine-rolled threaded steel hanger (11) includes a first hanger and a second hanger, the connection position of the first hanger and the second hanger is located at 40 cm from the top surface of the first layer bottom concrete (16), the first hanger and the second hanger are connected and fixed by a fine-rolled threaded steel connector (12), the first hanger is connected to the through-hole jack (10), the first layer bottom concrete (16) is poured at the position of the second hanger, and the bottom of the second hanger passes through the first layer bottom concrete (16) and the bottom plate (4) and is anchored below the crossbeam (3).

5. A shallow water steel hanging box construction method according to claim 4, characterized in that: The pouring thickness of the second layer of bottom sealing concrete (17) should cover the top surface of the suspension corbel (13) and be located below the precision-rolled threaded steel connector (12) until the anti-floating requirements are met.

6. A shallow water steel hanging box construction method according to claim 1, characterized in that: In step S5, the suspension bracket (13) is made of I-beam, and the I-beam on the side close to the steel casing (1) is connected to the outer wall of the steel casing (1) by a fillet weld. The top of the symmetrically arranged I-beam is installed with a steel pad (14) and is locked and fixed to the precision-rolled threaded steel suspension rod (11) by a nut (15).

7. A shallow water steel hanging box construction method according to claim 1, characterized in that: The suspension system in step S3 also includes a suspension distribution beam (9), which is symmetrically installed on the top of the suspension hanger (8), and the through-hole jack (10) is installed on the top of the suspension distribution beam (9).

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