Cable-stayed bent cap construction structure for Y-shaped pier of extra-large bridge

Abstract

The utility model provides a cable-stayed bent cap construction structure for a Y-shaped pier of an extra-large bridge, and belongs to the technical field of bridge construction. According to the technical scheme, the device comprises a pair of supporting frames, the supporting frames are arranged on the two sides of a Y-shaped pier respectively, vertical supporting rods are arranged on the top end faces of two inclined columns of the Y-shaped pier, steel strand systems are arranged between the vertical supporting rods and the supporting frames, and construction platforms are arranged on the supporting frames on the two sides. The structure has the advantages that according to the structure scheme provided by the utility model, the stress mode during capping beam construction is improved, the stress of the beam end is transmitted to the Y-shaped pier body through the steel strands and the vertical supporting rods, deformation of a capping beam formwork and deflection of the beam end can be effectively reduced, mounting and dismounting are simple and convenient, construction is convenient, construction quality can be effectively guaranteed, and construction efficiency is improved. The construction efficiency is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of bridge construction, in particular to a Y-shaped pier inclined-stayed cap beam construction structure for a super-large bridge. Background Art

[0002] In recent years, elevated bridges and roads have played an increasingly important role in transportation, and new elevated bridge projects have continued to emerge. In the construction of elevated bridges, the cap beam is an important component, and its construction quality and efficiency directly affect the stability of the entire bridge. The cantilever cap beam of the elevated bridge is usually constructed using the ground bracket method. If the cap beam height is high, the deadweight of the bracket will increase with the increase in height, and the environmental requirements such as the bearing capacity of the foundation and the lateral wind load of the bracket will also increase accordingly. How to improve construction efficiency and reduce construction costs is a technical problem that has always been faced in the field of bridge construction. At present, there are some technical solutions for cap beam construction. One of the commonly used methods is to prefabricate the cap beam segments and then assemble them one by one on the piers. Although this method can reduce construction time, for large bridges, the transportation and installation of prefabricated cap beam segments are difficult, and the stability of the overall structure may be affected. Some projects also use the method of bottom welding brackets to support and fix the formwork. This method also has its limitations, such as the difficulty in ensuring the quality of high-altitude welding, low welding construction efficiency, and the inability to adjust the bracket after welding, which may cause errors. For this reason, this paper provides a Y-shaped pier cable-stayed cap beam construction structure for a super-large bridge. Utility Model Content

[0003] The utility model aims to provide a Y-shaped pier cable-stayed cap beam construction structure for a super-large bridge which is simple, convenient and easy to install and construct.

[0004] This paper aims to solve the problems of great construction difficulty and low efficiency in the steel bar binding and concrete pouring of the Y-shaped cap beam of the super-large bridge. The weight of the cap beam is transferred to the bridge piers by means of inclined cables, which provides tension for the cantilever end of the cap beam and reduces the deformation of the cap beam formwork. The installation is simple and convenient, and the construction is convenient, which can effectively ensure the construction quality and improve the construction efficiency.

[0005] The utility model is achieved through the following measures:

[0006] A cable-stayed cap beam construction structure for a Y-shaped pier of an extra-large bridge, characterized in that it comprises a pair of support frames, wherein the pair of support frames are respectively arranged on both sides of the Y-shaped pier, vertical support rods are arranged on the top end surfaces of the two inclined columns of the Y-shaped pier, a steel strand system is arranged between the vertical support rods and the support frames, and construction platforms are arranged on the support frames on both sides.

[0007] The specific features of the utility model also include:

[0008] Embedded bolts are arranged on both side surfaces of the two inclined columns of the Y-shaped pier, and brackets are arranged on the embedded bolts, and sand barrel supports are arranged on the brackets, and the support frame is arranged on the sand barrel supports.

[0009] The support frame is a Bailey sheet longitudinal beam, and a transverse distribution beam is arranged between the Bailey sheet longitudinal beams on both sides. A wooden pad is laid on the transverse distribution beam, and the wooden pad covers the entire transverse distribution beam and is fixed on the transverse distribution beam.

[0010] The construction platform includes a base plate and a fence. The base plate is arranged on the upper side of the support frame, and the fence is arranged on the outer side of the upper side of the support frame away from the Y-shaped pier. The base plate can be made of wood, and the fence is a standardized fence used for protection.

[0011] The steel strand system includes horizontal steel strands, a beam bottom pad and a diagonal stay;

[0012] The horizontal steel strand is arranged between the two vertical support rods; the two sides of the side surface of the bottom plate of the beam are respectively arranged on the lower side surfaces of the support frames on both sides; the inclined portion includes high-quality rolled threaded steel and a pair of inclined steel strands respectively arranged at both ends of the high-quality rolled threaded steel, the high-quality rolled threaded steel coincides with the cap beam to be cast, that is, it is arranged inside the cap beam to be cast, and replacing the steel strand with the high-quality rolled threaded steel can reduce the structural damage to the cap beam, the free end of the inclined steel strand on one side of the inclined portion is arranged on the vertical support rod, and the free end of the inclined steel strand on the other side of the inclined portion is arranged on the corresponding bottom plate of the beam.

[0013] A pair of vertical support rods are arranged on the top end surfaces of the two inclined columns of the Y-shaped pier, and a transverse connecting rod is arranged between the pair of vertical support rods on the inclined columns, and the vertical support rods on both sides are connected by the transverse connecting rod.

[0014] The horizontal steel strands are provided in two groups and are respectively arranged between the two vertical support rods on the same side of the two inclined columns; the bottom beam pads are provided in two groups and are respectively arranged on the lower side surfaces of the support frames on both sides of the Y-shaped pier; the diagonal parts are provided in four groups, one end of the diagonal part is arranged on the vertical support rod, and the other end is arranged on the bottom beam pad on the corresponding side, and the bottom beam pad is a combination of an I-beam and a steel plate.

[0015] The construction steps are as follows:

[0016] S1. Pre-embed the vertical support rods and the pre-embedded bolts when casting the Y-shaped pier.

[0017] S2. After the concrete strength reaches the requirement, install the corbel and the sand cylinder support, install the Bailey plate longitudinal beam on the sand cylinder support, and lay the transverse distribution beam; the corbel adopts 700mm×200mm×30mm steel plate, and the gaps on both sides are wedged with small steel plates to prevent the displacement of the corbel steel plate after stress; the Bailey plate longitudinal beam is a three-piece Bailey plate, and the transverse distribution beam is an I-beam arranged at an interval of 80cm, and the width of each side exceeds the outer edge of the cap beam by 1m. During installation, attention should be paid to staggering the side form back ribs, and the transverse distribution beam is fully covered with wooden pads, and the wooden pads are fixed to the transverse distribution beam.

[0018] S3. Install the construction platform and use the standardized fence on the sides for protection.

[0019] S4. A truss is installed at the bottom of the variable-section end of the cap beam. The truss is welded from channel steel, with a total of 14 pieces.

[0020] S5. Install the bottom formwork, which adopts a steel-wood composite formwork. The arc chamfers on both sides of the cap beam adopt a standardized steel formwork, and the rest adopts 15mm thick bamboo plywood.

[0021] S6. Install the steel strand system, connect the horizontal steel strand with the two vertical support rods, adjust the length of the horizontal steel strand and fix it; connect the two ends of the fine-rolled threaded steel bar with the diagonal steel strand, one side of the diagonal steel strand passes through the bottom mold and is connected to the bottom plate of the beam, and the other side of the diagonal steel strand is connected to the vertical support frame.

[0022] S7. Preloading. Calculate the deadweight of concrete according to the size of the cap beam. The preloading weight is evenly distributed to the bottom formwork according to the actual cross-section of the cap beam. Preload step by step until it reaches 110% of the total weight. Unload after the average settlement is no more than 2mm for 12 consecutive hours. Keep it empty for 6 hours after unloading. During this period, observe the observation points at the support and bottom formwork continuously. According to the elastic deformation value and foundation settlement value of the support under the load of the beam section, add the elastic deformation value, foundation settlement value, and the arching amount after tensioning with the pre-arching degree required to be set due to other factors in the construction control, calculate the pre-arching degree that should be used during construction, adjust the bottom formwork elevation according to the calculated pre-arching degree, and adjust the steel strand system at the same time.

[0023] S8. Tie the cap beam reinforcement, install the side formwork, and pour the concrete.

[0024] S9. After the concrete strength reaches the requirement, the demolition is carried out in the order of supporting first and then demolishing. Finally, the vertical support frame, the precision-rolled threaded steel bars and other embedded parts are cut along the surface of the cap beam.

[0025] in addition:

[0026] 1. The steel strands can be adjusted appropriately under the conditions described in this article. The angles between the inclined steel strands and the vertical support rods can be adjusted according to actual needs by adjusting the height of the vertical support rods and the connection position between the inclined steel strands and the bottom plate of the beam.

[0027] 2. Channel steel and I-beam can be appropriately adjusted under the conditions described in this article and can be replaced by other materials with strong stability.

[0028] 3. The number and arrangement of vertical support rods and steel strands can be appropriately adjusted under the conditions described in this article.

[0029] The beneficial effects of the utility model are:

[0030] The structural scheme provided in this article improves the force mode during cap beam construction. The force at the beam end is transmitted to the Y-shaped pier body through steel strands and vertical support rods, which can effectively reduce the deformation of the cap beam formwork and the deflection of the beam end. The installation and dismantling are simple and convenient, and the construction is convenient. It can effectively ensure the construction quality and improve the construction efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic diagram of the main structure of an embodiment of the utility model.

[0032] Figure 2 It is a side structural schematic diagram of an embodiment of the utility model.

[0033] Figure 3 It is a schematic diagram of the top structure of an embodiment of the utility model.

[0034] Figure 4 It is a schematic diagram of the construction process of an embodiment of the utility model.

[0035] Among them, the figure markings are: 1. vertical support rod; 21. horizontal steel strand; 22. inclined steel strand; 3. high-precision rolled threaded steel; 4. beam bottom pad; 5. Y-shaped pier; 6. transverse connecting rod; 8. corbel; 9. sand cylinder support; 10. Bailey plate longitudinal beam; 11. transverse distribution beam; 12. construction platform; 13. fence; 14. truss; 15. bottom formwork. DETAILED DESCRIPTION

[0036] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

[0037] In the description of the present utility model, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present utility model, unless otherwise specified, "multiple" means two or more.

[0038] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0039] In order to clearly illustrate the technical features of this solution, this solution is described below through a specific implementation method.

[0040] See also Figure 1-4 A cable-stayed cap beam construction structure of a Y-shaped pier for a super-large bridge includes a pair of support frames, which are respectively arranged on both sides of the Y-shaped pier 5. Vertical support rods 1 are arranged on the top end surfaces of the two inclined columns of the Y-shaped pier 5. A steel strand system is arranged between the vertical support rods 1 and the support frames, and construction platforms 12 are arranged on the support frames on both sides.

[0041] Embedded bolts are arranged on both side surfaces of the two inclined columns of the Y-shaped pier 5, and brackets 8 are arranged on the embedded bolts. Sand barrel supports 9 are arranged on the brackets 8, and support frames are arranged on the sand barrel supports 9.

[0042] The support frame is a Bailey sheet longitudinal beam 10 , and a transverse distribution beam 11 is arranged between the Bailey sheet longitudinal beams 10 on both sides. A wooden pad is laid on the transverse distribution beam 11 , and the wooden pad covers the entire transverse distribution beam 11 and is fixed on the transverse distribution beam 11 .

[0043] The construction platform 12 includes a base plate and a fence 13. The base plate is arranged on the upper side of the support frame, and the fence 13 is arranged on the outer side of the support frame away from the Y-shaped pier 5. The base plate can be made of wood, and the fence 13 is a standardized fence 13, which is used for protection.

[0044] The steel strand system includes horizontal steel strands 21, a beam bottom pad 4 and a diagonal stay;

[0045] The horizontal steel strand 21 is arranged between two vertical support rods 1; the two sides of the upper side of the beam bottom pad 4 are respectively arranged on the lower side of the support frames on both sides; the inclined portion includes a fine-rolled threaded steel bar 3 and a pair of inclined steel strands 22 respectively arranged at both ends of the fine-rolled threaded steel bar 3, and the fine-rolled threaded steel bar 3 coincides with the cap beam 7 to be cast, that is, it is arranged inside the cap beam 7 to be cast. Replacing the steel strand with the fine-rolled threaded steel bar 3 can reduce the structural damage to the cap beam 7. The free end of the inclined steel strand 22 on one side of the inclined portion is arranged on the vertical support rod 1, and the free end of the inclined steel strand 22 on the other side of the inclined portion is arranged on the corresponding beam bottom pad 4.

[0046] A pair of vertical support rods 1 are arranged on the top end surfaces of the two inclined columns of the Y-shaped pier 5, and a transverse connecting rod 6 is arranged between the pair of vertical support rods 1 on the inclined columns, and the vertical support rods 1 on both sides are connected by the transverse connecting rod 6.

[0047] Two groups of horizontal steel strands 21 are provided and are respectively arranged between two vertical support rods 1 on the same side of two inclined columns; two groups of beam bottom pads 4 are provided and are respectively arranged on the lower side surfaces of the support frames on both sides of the Y-shaped pier 5; four groups of diagonal parts are provided, one end of the diagonal part is arranged on the vertical support rod 1, and the other end is arranged on the beam bottom pad 4 on the corresponding side, and the beam bottom pad 4 is a combination of I-beam and steel plate.

[0048] The construction steps are as follows:

[0049] S1. When pouring the Y-shaped pier 5, embed the vertical support rod 1 and the embedded bolts.

[0050] S2. After the concrete strength reaches the required level, install the corbel 8 and the sand tube support 9, install the Bailey longitudinal beam 10 on the sand tube support 9, and lay the transverse distribution beam 11; the corbel 8 adopts a 700mm×200mm×30mm steel plate, and the gaps on both sides are wedged with small steel plates to prevent the displacement of the corbel 8 steel plate after being stressed; the Bailey longitudinal beam 10 is a three-piece Bailey, and the transverse distribution beam 11 is an I-beam arranged at intervals of 80cm, and the width of each side exceeds the outer edge of the cap beam 7 by 1m. During installation, attention should be paid to staggering the side form back ribs, and the transverse distribution beam 11 is fully covered with wooden pads, which are fixed to the transverse distribution beam 11.

[0051] S3. Install the construction platform 12 and use standardized fences 13 on the sides for protection.

[0052] S4, the truss 14 is installed at the bottom of the variable cross-section of the end of the cap beam 7. The truss 14 is welded by channel steel, and there are 14 pieces in total.

[0053] S5. Install the bottom formwork 15. The bottom formwork 15 adopts a steel-wood composite formwork. The arc chamfers on both sides of the cap beam 7 adopt a shaped steel formwork, and the rest adopts 15mm thick bamboo plywood.

[0054] S6. Install the steel strand system, connect the horizontal steel strand 21 with the two vertical support rods 1, adjust the length of the horizontal steel strand 21 and fix it; connect the two ends of the fine-rolled threaded steel 3 with the inclined steel strand 22, one side of the inclined steel strand 22 passes through the bottom mold 15 and is connected to the bottom plate 4 of the beam, and the other side of the inclined steel strand 22 is connected to the vertical support frame.

[0055] S7, preloading. Calculate the deadweight of concrete according to the size of the cap beam 7. The preloading weight is evenly distributed to the bottom form 15 according to the actual cross section of the cap beam 7. Preload step by step until it reaches 110% of the total weight. Unload after the average settlement is no more than 2mm for 12 consecutive hours. Keep it empty for 6 hours after unloading. During this period, observe the observation points at the support and bottom form 15 continuously. According to the elastic deformation value and foundation settlement value of the support under the load of the beam section, add the elastic deformation value, foundation settlement value, and the arching amount after tensioning with the pre-arching degree required by other factors in the construction control, calculate the pre-arching degree that should be used during construction, adjust the elevation of the bottom form 15 according to the calculated pre-arching degree, and adjust the steel strand system at the same time.

[0056] S8, tie the reinforcement of cap beam 7, install the side formwork, and pour the concrete.

[0057] S9. After the concrete strength reaches the requirement, the demolition is carried out in the order of supporting first and then demolishing. Finally, the embedded parts such as the vertical support frame, the precision-rolled threaded steel bar 3, etc. are cut along the surface of the cap beam 7.

[0058] in addition:

[0059] 1. The steel strands can be adjusted appropriately under the conditions in this article. According to actual needs, the angles between the inclined steel strands and the vertical support rods can be adjusted by adjusting the height of the vertical support rods and the connection position between the inclined steel strands and the bottom plate of the beam.

[0060] 2. Channel steel and I-beam can be appropriately adjusted under the conditions in this article and can be replaced by other materials with strong stability.

[0061] 3. The number and arrangement of vertical support rods and steel strands can be appropriately adjusted under the conditions of this article.

[0062] Technical features not described in the present invention can be achieved through or by adopting existing technologies, and will not be elaborated here. Of course, the above description is not a limitation of the present invention, and the present invention is not limited to the above examples. Changes, modifications, additions or substitutions made by ordinary technicians in this technical field within the essential scope of the present invention should also fall within the scope of protection of the present invention.

Claims

1. A cable-stayed cap beam construction structure for a super-large bridge with a Y-shaped pier, characterized in that: The invention comprises a pair of support frames, wherein the pair of support frames are respectively arranged on both sides of a Y-shaped pier (5), and vertical support rods (1) are arranged on the top end surfaces of the two inclined columns of the Y-shaped pier (5), and a steel strand system is arranged between the vertical support rods (1) and the support frames, and construction platforms (12) are arranged on the support frames on both sides.

2. The cable-stayed cap beam construction structure of the Y-shaped pier of the super-large bridge according to claim 1 is characterized in that: Embedded bolts are arranged on both side surfaces of the two inclined columns of the Y-shaped pier (5), and brackets (8) are arranged on the embedded bolts. Sand barrel supports (9) are arranged on the brackets (8), and the support frame is arranged on the sand barrel supports (9).

3. The cable-stayed cap beam construction structure of the Y-shaped pier of the super-large bridge according to claim 1 is characterized in that: The support frame is a Bailey sheet longitudinal beam (10), and a transverse distribution beam (11) is arranged between the Bailey sheet longitudinal beams (10) on both sides, and a wooden pad is laid on the transverse distribution beam (11).

4. The cable-stayed cap beam construction structure of the Y-shaped pier of the super-large bridge according to claim 1 is characterized in that: The construction platform (12) comprises a base plate and a fence (13), wherein the base plate is arranged on the upper side of the support frame, and the fence (13) is arranged on the outer side of the upper side of the support frame away from the Y-shaped pier (5).

5. The cable-stayed cap beam construction structure of the Y-shaped pier of a super-large bridge according to claim 1 is characterized in that: The steel strand system comprises horizontal steel strands (21), a beam bottom pad (4) and a diagonal stay; The horizontal steel strand (21) is arranged between the two vertical support rods (1); the two sides of the upper side of the beam bottom pad (4) are respectively arranged on the lower side of the support frames on both sides; the inclined portion includes a fine-rolled threaded steel bar (3) and a pair of inclined steel strands (22) respectively arranged at both ends of the fine-rolled threaded steel bar (3), the free end of the inclined steel strand (22) on one side of the inclined portion is arranged on the vertical support rod (1), and the free end of the inclined steel strand (22) on the other side of the inclined portion is arranged on the corresponding beam bottom pad (4).

6. The cable-stayed cap beam construction structure of the Y-shaped pier of the super-large bridge according to claim 5 is characterized in that: A pair of vertical support rods (1) are arranged on the top end surfaces of the two inclined columns of the Y-shaped pier (5), and a transverse connecting rod (6) is arranged between the pair of vertical support rods (1) on the inclined columns.

7. The cable-stayed cap beam construction structure of the Y-shaped pier of the super-large bridge according to claim 6 is characterized in that: The horizontal steel strands (21) are provided in two groups and are respectively arranged between the two vertical support rods (1) on the same side of the two inclined columns; the bottom beam pads (4) are provided in two groups and are respectively arranged on the lower side surfaces of the support frame on both sides of the Y-shaped pier (5); and the diagonal parts are provided in four groups.

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