Construction method of special-shaped prestressed bridge deck slab of steel-concrete composite structure

Abstract

The invention discloses a construction method of a special-shaped prestressed bridge deck of a steel-concrete composite structure, and the method specifically comprises the following steps: S1, bridge deck formworks are spliced, and the bridge deck formworks comprise bottom formworks, side formworks, end formworks, shear key box molds, shear pins and hoisting holes; s2, the shear key box mold is in a comb plate form, the shear key box mold is installed after the end mold is installed, and then side molds are installed on the left side and the right side of the bottom mold; s3, a plurality of opposite-pull rod pieces are installed on the bottom die, and the two ends of the opposite-pull rod pieces are connected with the side dies on the two sides of the bottom die correspondingly; s4, after the shear key box mold is completed, the positions of shear pins are positioned according to design requirements in the interior, and the bridge deck and the bottom steel structure support are connected through grouting of pin holes; and S5, after the bridge deck slab formworks are assembled, reinforcing steel bar binding is conducted in the bridge deck slab formworks, and then concrete pouring and curing are conducted. According to the invention, through the pre-holing design of the tensioning notch, a die does not need to be additionally arranged, so that the tensioning notch and the bridge deck slab die are integrated, and the construction period is shortened.

Description

Technical Field

[0001] The invention belongs to the technical field of bridge structures, and in particular relates to a construction method for a special-shaped prestressed bridge deck of a steel-concrete composite structure. Background Art

[0002] As the degree of building industrialization gradually becomes an important indicator of the development level of the national and regional construction industry, the prefabricated construction technology of large civil engineering projects such as infrastructure railways, bridges, and airports has also developed rapidly, and gradually transformed towards a more efficient direction such as digitalization, greening, and informatization. Railway engineering has high structural requirements due to its special functions. Usually, it is a large-sized structure. In order to realize the possibility of prefabrication and assembly, prefabrication factories are usually built nearby for prefabrication. With the continuous innovation and development of materials and prefabrication processes, the prefabrication technology of lightweight large civil engineering components with enhanced post-casting connections has also been promoted, further improving the prefabrication rate of large civil engineering projects such as railways, and providing a strong guarantee for construction quality. At present, there is a gap in the prefabrication technology of special-shaped prestressed bridge decks in steel-concrete composite structures in the railway industry. This invention aims to develop a prefabrication technology for special-shaped prestressed concrete bridge decks in steel-concrete composite structures to solve the problems of template production and assembly, embedded parts positioning, process flow and energy saving and efficiency improvement in this complex prefabricated structure. Summary of the invention

[0003] The purpose of the present invention is to overcome the deficiencies in the above-mentioned prior art. The present invention provides a construction method for a special-shaped prestressed bridge deck with a steel-concrete composite structure. The present invention adopts a pre-opening design for tensioning grooves without the need for additional molds, thereby integrating the tensioning tooth mouth and the bridge deck mold, shortening the construction period and reducing production costs.

[0004] In order to achieve the above invention purpose, the technical solution provided by the present invention is as follows:

[0005] A construction method for a steel-concrete composite structure special-shaped prestressed bridge deck, the method specifically comprising the following steps:

[0006] S1, assembling the bridge deck formwork, the bridge deck formwork includes a bottom formwork, a side formwork, an end formwork, a shear key box formwork, a shear pin and a hoisting hole; cleaning the bottom formwork, after which the end forms are installed at the front and rear ends of the bottom formwork;

[0007] S2, the shear key box mold is in the form of a comb plate, and the longitudinal and transverse reinforcements of the wet cast belt at the shear key are reserved. After the end mold is installed in place, the shear key box mold is installed, and then the side molds are installed on the left and right sides of the bottom mold;

[0008] S3, installing multiple tie rods on the bottom form, the two ends of the tie rods are respectively connected to the side forms on both sides of the bottom form, two steel columns penetrating the bottom form are arranged in the middle of each tie rod to form a lifting hole for the concrete structure, and the tie rods are arranged in parallel;

[0009] S4. After the shear key box mold is completed, the shear pin position is located inside according to the design requirements. The pin and the bottom mold are fastened with nuts. The shear pin has a large upper head and a small lower head, which is convenient for pulling out the pin when removing the mold. A shear pin hole with a large upper mouth and a small lower mouth is formed in the concrete. The bridge deck and the bottom steel structure support are connected by grouting through the pin hole;

[0010] S5, after the above installation steps are completed, start the template reinforcement binding. After the bridge deck template is assembled, the reinforcement is bound inside the bridge deck template. When binding the reinforcement, first lay out the bridge deck transverse reinforcement and then process the shear key box mold detailed reinforcement, and then bind other beam body reinforcements, and finally locate and bury the bridge deck embedded parts. After the reinforcement binding is completed, concrete is poured and maintained to complete the production of the bridge deck.

[0011] Furthermore, the bottom mold is overall arc-shaped, with a bulge in the middle of the bottom mold, and pre-opening tooth drawing openings are provided on both sides of the bulge of the bottom mold. The side mold is a comb plate structure, and the end face of the side mold is provided with multiple rows of long slot holes. The side mold is vertically connected to the bottom mold, and the shear key box mold is a comb plate structure.

[0012] Furthermore, the shear key box mold is a rectangular groove as a whole, and the shear key box molds are symmetrically arranged on the front and rear sides of the bottom mold. One end of the shear key box mold is connected to the side mold, and the shear key box mold is vertically connected to the side mold.

[0013] Furthermore, the bottom mold cleaning is specifically as follows: using a high-pressure water gun to rinse the bottom mold surface, and using an angle grinder to grind the bottom mold to make the bottom mold surface flat and smooth; a bracket is provided at the bottom of the bottom mold, and when the bottom mold is installed, the bracket is adjusted to keep the bottom mold level.

[0014] Furthermore, after the bottom mold is cleaned, an oily release agent is coated on the surface of the bottom mold, and a retarder is coated on the sides of the side molds and the shear key box mold. After the retarder is coated on the sides of the side molds and the shear key box mold, the retarder on the side molds and the shear key box mold does not flow onto the bottom mold.

[0015] Furthermore, when the template reinforcement is tied, the reinforcement is tied on the bridge deck template, and the reinforcement passes through the comb plate structure from the side template and the shear key box mold to complete the reinforcement binding on the bridge deck template. The tensioning tooth block reinforcement in the pre-opening tooth mouth is tied and formed outside the template and then hoisted into the pre-opening tooth mouth.

[0016] Based on the above technical solution, the construction method of a special-shaped prestressed bridge deck with a steel-concrete composite structure in the present invention has achieved the following technical effects through practical application:

[0017] 1. The construction method of a steel-concrete composite structure special-shaped prestressed bridge deck of the present invention adopts a pre-opening design of tensioning notches without the need to add molds, so that the tensioning teeth and the bridge deck mold are integrated, thereby shortening the construction period.

[0018] 2. The construction method of a steel-concrete composite structure special-shaped prestressed bridge deck of the present invention ensures the accuracy of steel bar binding and improves the quality of the cast bridge deck by arranging comb plates on the side molds and shear key box molds. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 The present invention discloses a layout diagram of super-long prestressed ducts of a bridge deck in a construction method of a special-shaped prestressed bridge deck with a steel-concrete composite structure.

[0020] Figure 2 It is a longitudinal cross-sectional view of a bridge deck in a construction method of a special-shaped prestressed bridge deck with a steel-concrete composite structure according to the present invention.

[0021] Figure 3 The present invention discloses a structural diagram of a connection between a bridge deck and a steel box girder in a construction method of a special-shaped prestressed bridge deck of a steel-concrete composite structure.

[0022] Figure 4 It is a structural diagram of a bridge deck mold in a construction method of a steel-concrete composite structure special-shaped prestressed bridge deck of the present invention.

[0023] Figure 5 It is a bridge deck mold assembly sequence diagram in a construction method of a steel-concrete composite structure special-shaped prestressed bridge deck of the present invention.

[0024] Figure 6 The present invention discloses a shear pin structure diagram in a construction method of a special-shaped prestressed bridge deck with a steel-concrete composite structure.

[0025] Figure 7 It is a cross-sectional view of a pin positioning hole in a construction method of a special-shaped prestressed bridge deck of a steel-concrete composite structure according to the present invention. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical scheme and effect of the present invention clearer, the present invention is described below by specific examples. However, it should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present invention. In addition, in the following description, the description of known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present invention.

[0027] like Figure 1-7 The method for constructing a steel-concrete composite structure special-shaped prestressed bridge deck specifically comprises the following steps:

[0028] S1, assembling the bridge deck 1 template, the bridge deck 1 template includes a bottom mold 12, a side mold 11, an end mold 13 and a shear key box mold 14; cleaning the bottom mold 12, and installing the shear key box mold 14 on the bottom mold 12 after the bottom mold 12 is cleaned;

[0029] S2, after the shear key box mold 14 is installed, the end molds 13 are installed at the front and rear ends of the bottom mold 12, and the side molds 11 are installed at the left and right sides of the bottom mold 12;

[0030] S3, installing a plurality of tie rods 15 on the bottom mold 12, the two ends of the tie rods 15 are respectively connected to the side molds 11 on both sides of the bottom mold 12, and the tie rods 15 are arranged in parallel;

[0031] Two steel columns penetrating the bottom formwork are set in the middle of each tie rod to form a lifting hole for the concrete structure;

[0032] S4, after the shear key box mold 14 is completed, the shear pin position is located inside the box according to the design requirements, the pin is fastened to the bottom mold with a nut, the shear pin is in a structure form with a large upper head and a small lower head, which is convenient for pulling out the pin when removing the mold, and a shear pin hole with a large upper opening and a small lower opening is formed in the concrete, and the bridge deck 1 is connected to the bottom steel structure support through grouting of the pin hole;

[0033] S5, after the above installation steps are completed, start the template reinforcement binding. After the bridge deck 1 template is assembled, the reinforcement is bound inside the bridge deck 1 template. When binding the reinforcement, attention should be paid to first laying the bridge deck transverse reinforcement and then processing the shear key box detail reinforcement, and then binding other beam body reinforcements, and finally locating and burying the bridge deck embedded parts. After the reinforcement binding is completed, the concrete is configured and poured and cured to complete the production of the bridge deck; after the bridge deck 1 template is assembled, the reinforcement is bound inside the bridge deck 1 template. After the reinforcement binding is completed, the concrete is configured and poured and cured to complete the production of the bridge deck 1.

[0034] The bottom mold 12 is arc-shaped as a whole, with a convex arrangement in the middle of the bottom mold 12, and pre-opening tooth drawing openings 16 are arranged on both sides of the convex arrangement of the bottom mold 12. The side mold 11 is a comb plate structure, and the end face of the side mold 11 is provided with multiple rows of long slot holes. The side mold 11 is vertically connected to the bottom mold 12, and the shear key box mold 14 is a comb plate structure.

[0035] The shear key box mold 14 is a rectangular groove as a whole. The shear key box molds 14 are symmetrically arranged on the front and rear sides of the bottom mold 12. One end of the shear key box mold 14 is connected to the side mold 11, and the shear key box mold 14 is vertically connected to the side mold 11.

[0036] The cleaning of the bottom mold 12 is specifically as follows: use a high-pressure water gun to rinse the surface of the bottom mold 12, and use an angle grinder to grind the bottom mold 12 to make the surface of the bottom mold 12 flat and smooth; a bracket 17 is provided at the bottom of the bottom mold 12, and when the bottom mold 12 is installed, the bracket 17 is adjusted to keep the bottom mold 12 level.

[0037] After the bottom mold 12 is cleaned, an oily release agent is coated on the surface of the bottom mold 12 , and a retarder is coated on the sides of the side molds 11 and the shear key box mold 14 . After the retarder is coated on the sides of the side molds 11 and the shear key box mold 14 , the retarder on the side molds 11 and the shear key box mold 14 does not flow onto the bottom mold 12 .

[0038] When the template reinforcement is tied, the reinforcement is tied on the bridge deck 1 template. The reinforcement is tied through the comb plate structure from the side template 11 and the shear key box mold 14 to complete the reinforcement binding on the bridge deck 1 template. The tensioning tooth block reinforcement in the pre-opening tooth mouth 16 is tied and formed outside the template and then hoisted into the pre-opening tooth mouth 16.

[0039] By adopting the pre-opening design of the tensioning slot, there is no need to add a mold, so that the tensioning tooth mouth 16 and the bridge deck 1 mold are integrated, shortening the construction period.

[0040] like Figure 1-3 As shown, the prefabricated concrete bridge deck 1 is connected to the bottom steel box girder 2 base part through shear keys. The prefabricated concrete bridge decks 1 are connected by steel fiber concrete and tensioned after the strength reaches the required value. The prestressed bridge deck 1 is divided longitudinally along the entire span of the bridge. According to the size of the longitudinal division and the structural form, it can be divided into different types of bridge decks 1. The bridge decks 1 are connected by tooth bite post-casting when viewed from above. Post-casting connecting steel bars are reserved at the tooth section, and the spacing of the steel bars is evenly arranged. The longitudinal and transverse steel bars are reserved at the wet connection at the shear key, and are reserved by opening holes in the side form 11. It should be noted that the opening position should be accurate. The tooth notch is the shear pin distribution area. According to the structural form of the bridge deck 1, the prestressed pipes, anchoring tooth blocks, reserved steel bars and other issues need to be considered during prefabrication production; there are three types of super-long prestressed steel according to the length of the steel strands, namely S1, S2 and S3, of which S1 is arranged in two parallel lanes, with the transverse center line of the bridge deck as the dividing line. The prestressed steel on one side is numbered S1, S1, S2, S3, and the prestressed steel on the other side is numbered S1', S1', S2', S3'. There are three sizes of tooth blocks corresponding to the prestressed steel, which are arranged at the bottom of three different types of plates respectively;

[0041] The prestressed anchor is installed in the tensioning tooth block steel bar. Due to its hidden structure, the tensioning tooth block steel bar needs to be tied and formed outside the template in advance and then hoisted into the tooth block mold. After the anchor is fixed, the steel bars of the installation plate surface are tied and positioned according to the matching comb plate mold on the template according to the tooth block position. At the same time, the prestressed channel corrugated pipe is installed. The corrugated pipe positioning is fixed by welding with a well-shaped steel bar. When installing the prestressed corrugated pipe, special attention should be paid to the number of prestressed channels. According to the distribution of prestress in the whole bridge, the number of prestressed channels of the bridge deck 1 is different, including 2 holes, 3 holes, and 4 holes on both sides. There are also cases where the number of prestressed channels of the bridge deck 1 on both sides is different. Specifically, the prestressed distribution diagram and the bridge deck 1 layout drawing should be carefully compared during production implementation to prevent prestressed layout errors. Turn it into place before tying, and finally weld and position the embedded parts. For the pre-embedding of shear pin embedded parts, the tooling frame is used for precise positioning, and the lifting hole is welded on the shear pin at the same time, which is convenient for workers to pull out when the concrete is initially set, which is convenient for construction.

[0042] The concrete pouring of bridge deck 1 adopts segmented vibration, and the deck surface should be drained three times until it reaches the requirement of smoothness and flatness. The deck surface is designed to have a two-way slope, and attention should be paid to maintaining the slope when draining the surface.

[0043] Different types of bridge decks 1 have 2, 3, or 4 corrugated pipe bundles. During prefabrication, attention should be paid to the accurate positioning of the corrugated pipe bundles of different panels. During construction, the prestressed channel should be reserved according to the prestressed position and the tooth block structure diagram, and the channel position should be accurate. The anchor tooth block should be prefabricated together with the corresponding prefabricated bridge deck 1.

[0044] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, ordinary technicians in the field should understand that the specific implementation methods of the invention can still be modified or some technical features can be replaced by equivalents without departing from the spirit of the technical solution of the present invention, which should all be covered by the scope of the technical solution for protection of the present invention.

Claims

1. A construction method for a steel-concrete composite structure special-shaped prestressed bridge deck, characterized in that: The method specifically comprises the following steps: S1, assembling the bridge deck formwork, the bridge deck formwork includes a bottom formwork, a side formwork, an end formwork, a shear key box formwork, a shear pin and a hoisting hole; cleaning the bottom formwork, after which the end forms are installed at the front and rear ends of the bottom formwork; S2, the shear key box mold is in the form of a comb plate, and the longitudinal and transverse reinforcements of the wet cast belt at the shear key are reserved. After the end mold is installed in place, the shear key box mold is installed, and then the side molds are installed on the left and right sides of the bottom mold; S3, installing multiple tie rods on the bottom form, the two ends of the tie rods are respectively connected to the side forms on both sides of the bottom form, two steel columns penetrating the bottom form are arranged in the middle of each tie rod to form a lifting hole for the concrete structure, and the tie rods are arranged in parallel; S4. After the shear key box mold is completed, the shear pin position is located inside according to the design requirements. The pin and the bottom mold are fastened with nuts. The shear pin has a large upper head and a small lower head, which is convenient for pulling out the pin when removing the mold. A shear pin hole with a large upper mouth and a small lower mouth is formed in the concrete. The bridge deck and the bottom steel structure support are connected by grouting through the pin hole; S5, after the above installation steps are completed, start the template reinforcement binding. After the bridge deck template is assembled, the reinforcement is bound inside the bridge deck template. When binding the reinforcement, first lay out the bridge deck transverse reinforcement and then process the shear key box mold detailed reinforcement, and then bind other beam body reinforcements, and finally locate and bury the bridge deck embedded parts. After the reinforcement binding is completed, concrete is poured and maintained to complete the production of the bridge deck.

2. The construction method of a steel-concrete composite structure special-shaped prestressed bridge deck according to claim 1, characterized in that: The bottom mold is arc-shaped as a whole, with a bulge in the middle of the bottom mold, and pre-opening tooth drawing openings are provided on both sides of the bulge of the bottom mold. The side mold is a comb plate structure, and the end face of the side mold is provided with multiple rows of long slot holes. The side mold is vertically connected to the bottom mold, and the shear key box mold is a comb plate structure.

3. The construction method of a steel-concrete composite structure special-shaped prestressed bridge deck according to claim 2, characterized in that: The shear key box mold is a rectangular groove as a whole, and the shear key box molds are symmetrically arranged on the front and rear sides of the bottom mold. One end of the shear key box mold is connected to the side mold, and the shear key box mold is vertically connected to the side mold.

4. The construction method of a steel-concrete composite structure special-shaped prestressed bridge deck according to claim 3, characterized in that: The bottom mold cleaning is specifically as follows: use a high-pressure water gun to rinse the bottom mold surface, and use an angle grinder to grind the bottom mold to make the bottom mold surface flat and smooth; a bracket is provided at the bottom of the bottom mold, and when the bottom mold is installed, the bottom mold is kept level by adjusting the bracket.

5. The construction method of a steel-concrete composite structure special-shaped prestressed bridge deck according to claim 4, characterized in that: After the bottom mold is cleaned, an oily release agent is coated on the surface of the bottom mold, and a retarder is coated on the side of the side mold and the shear key box mold. After the retarder is coated on the side mold and the shear key box mold, the retarder on the side mold and the shear key box mold does not flow onto the bottom mold.

6. The construction method of a steel-concrete composite structure special-shaped prestressed bridge deck according to claim 4, characterized in that: When the template reinforcement is tied, the reinforcement is tied on the bridge deck template. The reinforcement is passed through the comb plate structure from the side template and the shear key box mold to complete the reinforcement binding on the bridge deck template. The tensioning tooth block reinforcement in the pre-opening tooth mouth is tied and formed outside the template and then hoisted into the pre-opening tooth mouth.

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