A wet joint construction method for cast-in-place steel-concrete composite beam bridge deck

Abstract

The present invention relates to a wet joint construction method for a steel-concrete composite beam cast-in-place bridge deck, comprising the following steps: first, installation of a supporting steel base; second, installation of a load-bearing beam; third, installation of a distribution beam and a bottom formwork; fourth, reinforcement binding; fifth, installation of a steel sleeve; sixth, casting of the bridge deck; and seventh, removal of the formwork and the support system. The present invention aims to provide a wet joint construction method for a steel-concrete composite beam cast-in-place bridge deck, in which the support system can be easily disassembled for turnover use, does not affect the existing internal operation, and can ensure the flatness of the bridge deck produced by the wet joint method, thereby solving the problem that the support method affects road traffic.

Description

Technical Field

[0001] The invention relates to the technical field of bridges, and in particular to a wet joint construction method for a cast-in-situ steel-concrete composite beam bridge deck. Background Art

[0002] A steel-concrete composite beam is a beam that is connected by a steel beam and a concrete slab and can bear force together in the cross section. The main construction process is to process the steel beam segments in the factory, transport them to the site for hoisting and assembly into steel beams (steel box beams), and then install precast concrete slabs or cast-in-place concrete bridge decks. Practice has proved that steel-concrete composite beams take into account the advantages of both steel structures and concrete structures, have significant technical, economic and social benefits, and are one of the important development directions of structural systems. Therefore, they have been widely used in bridge engineering. When the bridge deck is cast in situ, the main support method is the full-height support method and the beam-column support method. Among them, the full-height support and the beam-column support method both occupy the space under the bridge, which will affect the operational efficiency of ground traffic when crossing existing roads, and there are major safety hazards. Summary of the invention

[0003] The present invention aims to provide a wet joint construction method for cast-in-place bridge decks of steel-concrete composite beams, whose support system can be easily disassembled for turnover use, does not affect existing internal operations, and can ensure the flatness of the bridge deck produced by the wet joint method, thereby solving the problem that the support method affects road traffic.

[0004] The above technical problems are solved by the following technical solutions: a wet joint construction method for a steel-concrete composite beam cast-in-place bridge deck, the first step, the installation of the supporting steel base: a row of supporting steel bases are welded on the top surface of the opposite side of two adjacent steel box girders, the steel box girders extend along the extension direction of the bridge, the supporting steel bases are distributed along the extension direction of the bridge, and a wet joint is formed between the two adjacent steel box girders, one end of the supporting steel base extends into the wet joint, and the part of the supporting steel base located at the wet joint is provided with a supporting steel base part hanger rod hole; the second step, the installation of the load-bearing beam: the upper ends of a plurality of hangers are passed through the supporting steel base part hangers one by one The lower ends of the hangers are connected with the upper hanging nuts after passing through the hanger holes of the steel load-bearing beam on the steel load-bearing beam one by one, and are connected with the hanging blocks. The steel load-bearing beams are distributed along the extension direction of the bridge, and the steel load-bearing beams extend along the width direction of the bridge. Both ends of a steel load-bearing beam are connected with the same hanger. A protective sleeve is provided on the part of the hanger below the upper surface of the supporting steel base. The protective sleeve is used to prevent the hanger from being poured together with the concrete when pouring the wet joints. The third step is to install the distribution beam and the bottom formwork: install the distribution beam on the load-bearing beam, the distribution beam is distributed along the width direction of the bridge, and the distribution beam extends along the extension direction of the bridge. , lay the bottom formwork on the distribution beam, the bottom formwork is provided with a bottom formwork hanger hole, the protective sleeve and the hanger pass through the bottom formwork hanger hole, the hanger, steel load-bearing beam, supporting steel base and distribution beam constitute a support system; the fourth step, steel bar binding: adjust the bottom formwork elevation to meet the requirements, and tie the steel bars above the bottom formwork. The steel bars constitute the steel bar skeleton of the bridge deck at the wet joint; the fifth step: install the steel sleeve: cover the hanger above the supporting steel base to the thickness of the bridge deck with a steel sleeve, and the top elevation of the steel sleeve is controlled to be 08 mm to 12 mm lower than the bridge deck elevation, and cover the top of the steel pipe with a slurry stopper, and the slurry stopper cover After that, the upper surface of the stop plug is just flush with the design elevation of the bridge deck to ensure the sealing of the wet joint concrete pouring; Step 6, pouring the bridge deck: pouring concrete at the wet joint and the steel load-bearing beam at one time to form the bridge deck, and the supporting steel base, protective sleeve and steel sleeve are all poured together with the bridge deck; Step 7, removing the formwork and support system: when the concrete strength of the bridge deck reaches 2.5MPa, remove the formwork and support system except the supporting steel base, and the removed formwork and support system are reused for subsequent construction. When removing, remove the stop plug on the steel sleeve, remove the upper suspension nut and remove the hanger. The support system mold can be easily disassembled for use of the shaft, and the template is set up when the steel box beam is used as support for suspension, which will not affect ground traffic. Since the supporting steel base is fixed on the rigid box girder in a cantilever manner in the suspension method, it does not interfere with the pouring of the wet joints, so that the supporting steel base can be made in the upper and lower dimensions without protruding from the pouring inside, thus ensuring the flatness of the inside. At this time, in order to meet the strength requirements, it can be achieved by increasing the number.If it is suspended on two steel box girders at the same time through a crossbeam, in order not to interfere with the pouring of the wet joint and to ensure the strength, the up and down dimensions of the beam can only be designed to be larger, which will protrude from the road surface and affect the flatness of the inside, making it very inconvenient to level the inside later.

[0005] Preferably, in the seventh step, the disassembly is performed by a discharging device, which includes a bracket composed of longitudinal beams and transverse beams and supported under the steel load-bearing beam, and a plurality of steel cables connected to the bracket at the lower end. A plurality of vertical cable tubes are pre-buried in the bridge deck, and the vertical cable tubes are located in the wet joints. The upper ends of the steel cables pass through the vertical cable tubes one by one and extend to the upper surface of the bridge deck. The steel load-bearing beam is supported by the bracket by tightening the steel cables, and then the stop plug on the steel casing is removed, the upper suspension nut is removed, and the steel cable is released so that the formwork and the support system are dragged by the bracket and placed on the ground. The support system can be easily disassembled with the cast-in-place bridge deck as support.

[0006] Preferably, after the formwork and the support system are removed, cement slurry is filled into the steel casing and the vertical cable tube to seal them.

[0007] Preferably, the hanging block is a nut threadedly connected to a hanging rod, and the hanging rod is made of threaded steel, which is convenient to manufacture.

[0008] Preferably, the supporting steel base is formed by cutting off the channel steel, and the supporting steel base is waterproofly connected to the steel box girder in a side-placed manner. The length of the supporting steel base is 20 cm, and the supporting steel base extends along the width direction of the bridge. The supporting steel base is provided with a steel plate rib welded at the position where the supporting steel base hanger hole is provided for reinforcement, and the upper and lower ends of the steel plate rib are welded together with the two side walls of the channel steel constituting the supporting steel base, which are away from the end of the bottom wall of the channel steel. The strength of the connection point can be improved. The material is convenient to obtain and the cost is low.

[0009] Preferably, the supporting steel base and the steel beam are tightly and fully welded together, and the welding length of the supporting steel base and the steel box beam is more than 5 cm, preferably 10 cm.

[0010] As a preferred method, in the second step, the suspension rod is first connected to the steel load-bearing beam, and then the suspension rods on both sides of the steel load-bearing beam are inserted from bottom to top into the suspension rod holes of the supporting steel base and then threadedly fixed together with the upper suspension nuts. This is convenient for assembling and adjusting the mold.

[0011] As a preference, the stop plug is factory-customized and is provided with a small diameter section, which is inserted into the steel casing. The outer diameter of the stop plug is equal to the outer diameter of the casing, and the thickness of the stop plug is 1 cm. This can not only make the stop plug reliably cover the steel casing, but also reduce the force when the stop plug is poured together with the concrete inside.

[0012] Preferably, the distribution beam is made of square wood, and the bottom formwork is made of bamboo plywood.

[0013] Preferably, an explosive pack is arranged in the steel casing, and the fuse of the explosive pack passes through the stop plug and is output to the bridge deck, and the stop plug is taken out by the explosive force generated by igniting the explosive pack in the seventh step. It is convenient and labor-saving to drive the stop plug.

[0014] The beneficial effects of the present invention are as follows: the support system in the method is of bottom-supported type, and is suspended by being anchored to a supporting steel base welded at intervals on the top of the steel box girder, so as to provide a stable and reliable support platform for the wet joint formwork; secondly, the support base is directly cast in the bridge deck, eliminating the hanging crossbeam structure, and providing conditions for the one-time integral cast-in-place of the wet joint and the bridge deck paver, which is beneficial to the control of the flatness of the bridge deck and the casting quality; thirdly, the support system can be processed and manufactured using existing materials and recycled for turnover, which is economical, energy-saving and environmentally friendly, and has good economic and social benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a schematic elevation diagram of the support system. The left and right directions in the figure are the width directions of the bridge.

[0016] Figure 2 Schematic diagram of the top view of the support system;

[0017] Figure 3 It is a schematic diagram of the connection between the supporting steel base and the steel load-bearing beam;

[0018] Figure 4 A top view schematic diagram of the support system when being disassembled;

[0019] Figure 5 It is a partial schematic diagram of the steel casing in the second embodiment.

[0020] In the figure: supporting steel base 1, steel box girder 2, wet joint 3, hanger 4, upper hanging nut 5, hanging block 6, protective casing 7, distribution beam 8, bottom formwork 9, steel casing 10, slurry stopper 11, upper surface of slurry stopper 12, bridge deck 13, longitudinal beam 20, cross beam 14, vertical cable tube 15, small diameter section 18, explosive pack 16, fuse of explosive pack 17, steel plate rib 19, steel load-bearing beam 21. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments; based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0022] Example 1, see Figures 1 to 4A wet joint construction method for a steel-concrete composite beam cast-in-place bridge deck, the first step, the installation of the support steel base 1: a row of support steel bases are welded on the top surfaces of the opposite sides of two adjacent steel box girders 2, the steel box girders extend along the extension direction of the bridge, the support steel bases are distributed along the extension direction of the bridge, and a wet joint 3 is formed between the two adjacent steel box girders, one end of the support steel base extends into the wet joint, and the support steel base portion located at the wet joint is provided with a support steel base portion hanger hole; the second step, the installation of the load-bearing beam: the upper ends of a plurality of hangers 4 are passed through the hanger holes of the support steel base portion one by one, and then connected together with the upper suspension nuts 5, the hangers The lower ends are connected to the suspension blocks 6 after passing through the hanger holes of the steel load-bearing beams 21 one by one. The steel load-bearing beams are distributed along the extension direction of the bridge and extend along the width direction of the bridge. Both ends of a steel load-bearing beam are connected to the same hanger. A protective sleeve 7 is provided on the part of the hanger below the upper surface of the supporting steel base. The protective sleeve is used to prevent the hanger from being poured together with the concrete when pouring the wet joints. The third step is to install the distribution beam and the bottom formwork: install the distribution beam 8 on the load-bearing beam. The distribution beams are distributed along the width direction of the bridge and extend along the extension direction of the bridge. A bottom formwork 9 is laid on the distribution beam. The bottom formwork is provided with a There is a hanger hole in the bottom mold, and the protective sleeve and the hanger pass through the hanger hole in the bottom mold. The hanger, steel load-bearing beam, supporting steel base and distribution beam constitute a support system; the fourth step, steel bar binding: adjust the bottom mold elevation to meet the requirements, and tie the steel bars above the bottom mold. The steel bars constitute the steel bar skeleton located at the wet joint of the bridge deck; the fifth step: install the steel sleeve: the hanger above the supporting steel base to the thickness of the bridge deck is covered with a steel sleeve 10, and the elevation of the top of the steel sleeve is controlled to be 08 mm to 12 mm lower than the elevation of the bridge deck, which is 1 cm in this embodiment, and the slurry stopper 11 is covered on the top of the steel pipe. After the slurry stopper is covered, it stops The upper surface 12 of the slurry plug is just flush with the design elevation of the bridge deck to ensure the sealing of the wet joint concrete when pouring; the sixth step is to pour the bridge deck: the wet joint and the steel load-bearing beam are poured with concrete at one time to form the bridge deck 13, and the supporting steel base, protective sleeve and steel sleeve are all poured together with the bridge deck; the seventh step is to remove the formwork and support system: when the concrete strength of the bridge deck reaches 2.5MPa, remove the formwork and support system except the supporting steel base, and the removed formwork and support system are reused for subsequent construction. When removing, remove the slurry stop plug on the steel sleeve, remove the upper suspension nut to remove the hanger.In the seventh step, the disassembly is performed by a discharging device, which includes a bracket composed of a longitudinal beam 20 and a cross beam 14 and supported under the steel load-bearing beam, and a plurality of steel cables connected to the bracket at the lower end. A plurality of vertical cable tubes 15 are pre-buried in the bridge deck. The vertical cable tubes and protective sleeves are both plastic tubes. The vertical cable tubes are located in the wet joints. The upper ends of the steel cables pass through the vertical cable tubes one by one and extend to the upper surface of the bridge deck. The steel load-bearing beam is supported by the bracket by tightening the steel cables. In this embodiment, the interference is pulled by a hand winch, and then the slurry stopper on the steel casing is removed, the upper suspension nut is removed, and the steel cable is released (i.e., the steel cable is loosened by the hand winch) so that the template and the support system are dragged by the bracket and placed on the ground. After the template and the support system are removed, cement slurry is filled in the steel casing and the vertical cable tubes to seal them. The suspension block is a nut threadedly connected to the hanger rod, and the hanger rod is made of threaded steel. The supporting steel base is formed by cutting off the channel steel. The supporting steel base is waterproofly connected to the steel box beam in a side-mounted manner. The length of the supporting steel base is 20 cm. The supporting steel base extends along the width direction of the bridge. The supporting steel base is provided with a steel plate rib 19 welded to the part where the supporting steel base has a hanger hole for reinforcement. The upper and lower ends of the steel plate rib are welded together with the two side walls of the channel steel constituting the supporting steel base, which are away from the end of the bottom wall of the channel steel. The supporting steel base is closely connected to the steel beam and fully welded together. The welding length of the supporting steel base and the steel box beam is more than 5 cm, and is 10 cm in this embodiment. In the second step, the hanger is first connected to the steel load-bearing beam, and then the hangers on both sides of the steel load-bearing beam are respectively inserted from bottom to top into the hanger holes of the supporting steel base, and then the same hanging nuts are threaded and fixed together. The stop plug is customized by the factory. The stop plug is provided with a small diameter section 18, which is inserted into the steel casing. The outer diameter of the stop plug is equivalent to the outer diameter of the casing, and the thickness of the stop plug is 1 cm. The distribution beam is square wood, and the bottom mold is bamboo plywood.

[0023] Embodiment 2 is different from Embodiment 1 in that:

[0024] See also Figure 5 An explosive pack 16 is arranged in the steel casing, and the fuse 17 of the explosive pack passes through the stop plug and is output to the bridge deck. In the seventh step, the stop plug is taken out by the explosive force generated by igniting the explosive pack.

Claims

1. A wet joint construction method for cast-in-place steel-concrete composite beam bridge deck, characterized in that: The first step is to install the supporting steel base: weld a row of supporting steel bases on the top surface of the opposite side of two adjacent steel box girders, the steel box girders extend along the extension direction of the bridge, and the supporting steel bases are distributed along the extension direction of the bridge. A wet joint is formed between the two adjacent steel box girders, and one end of the supporting steel base extends into the wet joint. The part of the supporting steel base located at the wet joint is provided with a supporting steel base hanger hole; the second step is to install the load-bearing beam: the upper ends of several hangers are passed through the hanger holes of the supporting steel base one by one and then connected together with the upper suspension nuts, the lower ends of the hangers are passed through the hanger holes of the steel load-bearing beam on the steel load-bearing beam one by one and then connected together with the suspension block, the steel load-bearing beam is distributed along the extension direction of the bridge, and the steel load-bearing beam extends along the width direction of the bridge. Both ends of the steel load-bearing beam are connected with the same hanger rod, and a protective sleeve is provided on the part of the hanger rod below the upper surface of the supporting steel base, and the protective sleeve is used to prevent the hanger rod from being poured together with the concrete when pouring the wet joint; the third step, the distribution beam and the bottom formwork are installed: the distribution beam is installed on the load-bearing beam, the distribution beam is distributed along the width direction of the bridge, and the distribution beam extends along the extension direction of the bridge, and the bottom formwork is laid on the distribution beam, and the bottom formwork is provided with a bottom formwork hanger rod hole, and the protective sleeve and the hanger rod pass through the bottom formwork hanger rod hole, and the hanger rod, the steel load-bearing beam, the supporting steel base and the distribution beam constitute a support system; the fourth step, steel bar binding: the bottom formwork elevation is adjusted to meet the requirements, and steel bars are bound above the bottom formwork, and the steel bars constitute the steel bar skeleton of the bridge deck located at the wet joint; Step 5: Install steel sleeves: Use steel sleeves to cover the hangers from the supporting steel base to the thickness of the bridge deck. The top elevation of the steel sleeve is controlled to be 08 mm to 12 mm lower than the bridge deck elevation. Cover the top of the steel pipe with a slurry stopper. After the slurry stopper is covered, the upper surface of the slurry stopper is just flush with the design elevation of the bridge deck to ensure the sealing when pouring wet joint concrete; Step 6, pouring bridge deck: Concrete is poured at the wet joint and the steel load-bearing beam at one time to form the bridge deck. The supporting steel base, protective sleeve and steel sleeve are all poured together with the bridge deck; Step 7, removal of formwork and support system: When the concrete strength of the bridge deck reaches 2.5MPa, remove the formwork and support system except the supporting steel base. The removed formwork and support system are reused for subsequent construction. When removing, remove the slurry stopper on the steel sleeve and remove the upper hanging nut to remove the hanger.

2. A wet joint construction method for cast-in-situ steel-concrete composite beam bridge deck according to claim 1, characterized in that: In the seventh step, disassembly is carried out through an unloading device, which includes a bracket composed of a longitudinal beam and a transverse beam and supported under the steel load-bearing beam, and a plurality of steel cables connected to the bracket at the lower end. A plurality of vertical cable tubes are pre-embedded in the bridge deck, and the vertical cable tubes are located in the wet joints. The upper ends of the steel cables pass through the vertical cable tubes one by one and extend to the upper surface of the bridge deck. The steel load-bearing beam is supported by tightening the bracket with the steel cables, and then the slurry stopper on the steel casing is removed, the upper suspension nut is removed, and the steel cables are released so that the formwork and the support system are dragged by the bracket and placed on the ground.

3. The wet joint construction method of a cast-in-place steel-concrete composite beam bridge deck according to claim 2 is characterized in that: After the formwork and support system are removed, cement slurry is filled into the steel casing and vertical cable tube to seal them.

4. A wet joint construction method for cast-in-situ steel-concrete composite beam bridge deck according to claim 1, 2 or 3, characterized in that: The hanging block is a nut threadedly connected to a hanging rod, and the hanging rod is made of threaded steel.

5. A wet joint construction method for cast-in-situ steel-concrete composite beam bridge deck according to claim 1, 2 or 3, characterized in that: The supporting steel base is formed by cutting off the channel steel, and the supporting steel base is connected to the steel box girder in a waterproof manner on its side. The length of the supporting steel base is 20 cm, and the supporting steel base extends along the width direction of the bridge. The supporting steel base is provided with steel plate ribs welded to the part where the hanger holes of the supporting steel base are reinforced, and the upper and lower ends of the steel plate ribs are welded together with the two side walls of the channel steel constituting the supporting steel base, which are away from the bottom wall of the channel steel.

6. A wet joint construction method for cast-in-situ steel-concrete composite beam bridge deck according to claim 1, 2 or 3, characterized in that: In the second step, first connect the hanger rod to the steel load-bearing beam, and then insert the hangers on both sides of the steel load-bearing beam from bottom to top into the hanger rod holes of the supporting steel base and fix them together with the upper hanging nut threads.

7. A wet joint construction method for cast-in-situ steel-concrete composite beam bridge deck according to claim 1, 2 or 3, characterized in that: The slurry stopper is provided with a small diameter section, which is inserted into the steel casing. The outer diameter of the slurry stopper is equivalent to the outer diameter of the steel casing, and the thickness of the slurry stopper is 1 cm.

8. A wet joint construction method for cast-in-situ steel-concrete composite beam bridge deck according to claim 1, 2 or 3, characterized in that: The distribution beam is made of square wood, and the bottom formwork is made of bamboo plywood.

9. A wet joint construction method for cast-in-situ steel-concrete composite beam bridge deck according to claim 1 or 2, characterized in that: An explosive pack is arranged in the steel casing, and the fuse of the explosive pack passes through the stop plug and is output to the bridge deck. In the seventh step, the stop plug is taken out by the explosive force generated by igniting the explosive pack.

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