Hogging moment area full-prestress steel-concrete combined continuous beam bridge and construction method thereof

Abstract

The invention discloses a hogging moment area full-prestress steel-concrete combined continuous beam bridge and a construction method thereof.The hogging moment area full-prestress steel-concrete combined continuous beam bridge comprises sagging moment area steel main beams and hogging moment area steel main beams, and the sagging moment area steel main beams and the hogging moment area steel main beams are alternately arranged and sequentially spliced to form an integral main beam; the integral main beam is installed on the piers, the sagging moment area steel-concrete combined bridge deck is installed on the sagging moment area steel main beam, and the hogging moment area steel-concrete combined bridge deck is installed on the hogging moment area steel main beam. A post-cast strip steel-concrete combined bridge deck is arranged at the position, between the sagging moment area steel-concrete combined bridge deck and the hogging moment area steel-concrete combined bridge deck, of the sagging moment area steel girder. The effective pre-stress of the concrete in the hogging moment area of the continuous composite beam is remarkably improved, the concrete in the hogging moment area can be prevented from cracking, when the longitudinal pre-stressed tendons in the bridge deck are tensioned, the steel main beam only serves as a support and does not participate in sharing the pre-stress, and the effective pre-compressive stress of the concrete in the hogging moment area is remarkably improved.

Description

Technical Field

[0001] The present invention relates to the technical field of bridge engineering, and in particular to a fully prestressed steel-concrete composite continuous beam bridge in a negative bending moment zone and a construction method thereof. Background Art

[0002] Steel-concrete composite beams are composed of steel beams and concrete slabs connected into a whole by shear connectors and bear the force together. They combine the material characteristics of steel's tensile resistance and concrete's compressive resistance. They have the advantages of high structural rigidity, high bearing capacity, and strong spanning ability. They are currently widely used in municipal bridges, highway bridges and other fields.

[0003] For simply supported beam bridges, steel-concrete composite beam bridges have good mechanical properties. However, for multi-span bridges, in order to improve driving comfort and make the structural stress more reasonable, they are generally made into continuous beam bridges. The bridge deck is continuous and the beam height can be further reduced, which has better performance. However, in the negative bending moment area of ​​the continuous composite beam, the concrete will be subjected to tension. After the concrete bridge deck cracks, the stiffness of the composite beam will decrease. The steel bars in the concrete slab, the studs at the intersection, and the steel beams are prone to corrosion, which reduces the durability of the bridge. Therefore, how to prevent the concrete from cracking in the negative bending moment area of ​​the steel-concrete composite continuous beam has become a problem that technicians in this field need to solve.

[0004] At present, there are two major types of negative moment cracking measures commonly used in engineering. One is the non-prestressed method, such as 1) using RPC (reactive powder concrete), UHPC (ultra-high performance concrete), STC (ultra-high toughness concrete), ECC (fiber cement-based composite materials) with high tensile strength to replace ordinary concrete in the negative moment area to achieve the effect of cracking resistance, but the material cost is high; 2) using bolts that are resistant to pull-out but not shear to achieve the effect of composite beams in the negative moment area and reduce the tensile stress of concrete bridge decks; 3) increasing the tensile strength of concrete in the negative moment area. Reinforcement amount; 4) Double-sided combined action, by pouring concrete on the bottom plate in the negative bending moment area, the moment of inertia of the cross section is increased and the stress of the cross section is reduced. Methods 2) to 4) can only reduce the crack width and cannot avoid the occurrence of cracks. The effect is not as good as the second type of prestressed method, including: preload method, support displacement method, prestressing method, etc. The effective prestress applied by the preload method, support displacement method and ordinary prestressing method is relatively limited. The post-combination prestressing method has a better effect, but it is currently mostly used in prefabricated bridge panels, and the bridge panels at the joints are prone to diseases. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a fully prestressed steel-concrete composite continuous beam bridge in a negative bending zone with a simple structure and convenient construction, and provides a construction method thereof.

[0006] The technical solution of the present invention to solve the above technical problems is: a fully prestressed steel-concrete composite continuous beam bridge in a negative bending zone, comprising a steel main beam in a positive bending zone, a steel main beam in a negative bending zone, a steel crossbeam, a steel-concrete composite bridge deck in a positive bending zone, a steel-concrete composite bridge deck in a negative bending zone and a post-cast steel-concrete composite bridge deck, wherein the steel main beams in the positive bending zone and the steel main beams in the negative bending zone are arranged alternately and spliced ​​in sequence to form an integral main beam, the integral main beam is installed on the bridge pier through a support, the steel-concrete composite bridge deck in the positive bending zone is installed on the steel main beam in the positive bending zone, the steel-concrete composite bridge deck in the negative bending zone is installed on the steel main beam in the negative bending zone, and a post-cast steel-concrete composite bridge deck is arranged at a position between the steel-concrete composite bridge deck in the positive bending zone and the steel-concrete composite bridge deck in the negative bending zone; the steel bottom mold of the negative bending zone bridge deck in the steel-concrete composite bridge deck in the negative bending zone and the steel bottom mold of the negative bending zone in the steel main beam in the negative bending zone A built-in wet joint is formed on the top plate of the main beam. During construction, the longitudinal prestressed tendons in the steel-concrete composite bridge deck in the negative bending moment area are tensioned first. At this time, the steel main beam in the negative bending moment area serves as a supporting platform for the steel-concrete composite bridge deck in the negative bending moment area, which does not affect the application of concrete prestressing of the bridge deck. Then, the built-in wet joint space is poured. The built-in wet joint space is a closed section. The built-in wet joint prestressing system is used to make the built-in wet joint a closed space. Before the initial setting of the built-in wet joint slurry, the high-strength steel wire bundle in the built-in wet joint prestressing system is tensioned. At this time, the built-in wet joint slurry and the top surface grooved plate bottom bolts and the bottom surface negative bending moment area steel main beam bolts do not form an effective connection stiffness. The prestress tensioned by the high-strength steel wire bundle only acts on the built-in wet joint slurry, forming a fully prestressed built-in wet joint slurry, so that the steel-concrete composite bridge deck in the negative bending moment area is in a fully prestressed concrete stress state in the longitudinal direction of the bridge.

[0007] The above-mentioned fully prestressed steel-concrete composite continuous beam bridge in the negative bending moment area, the steel main beam in the positive bending moment area includes a top plate of the steel main beam in the positive bending moment area, a bottom plate of the steel main beam in the positive bending moment area, a web plate of the steel main beam in the positive bending moment area, a stiffening rib of the steel main beam in the positive bending moment area, a stud of the steel main beam in the positive bending moment area, a welding bolt of the steel main beam in the positive bending moment area, and a sealing rubber strip; the web plate of the steel main beam in the positive bending moment area is welded with the top plate of the steel main beam in the positive bending moment area and the bottom plate of the steel main beam in the positive bending moment area, and the web plate of the steel main beam in the positive bending moment area, the top plate of the steel main beam in the positive bending moment area and the positive bending moment area A number of positive bending zone steel main beam stiffening ribs are arranged on the bottom plate of the steel main beam, a number of positive bending zone steel main beam bolts are welded on the top plate of the positive bending zone steel main beam, a number of positive bending zone steel main beam welding bolts for fixing the positive bending zone steel-concrete composite bridge deck are arranged on both sides of the top plate of the positive bending zone steel main beam, and a full-length sealing rubber strip is arranged on both sides of the top plate of the positive bending zone steel main beam to prevent leakage when pouring bridge deck concrete; the positive bending zone steel main beam is provided with multiple strips according to the width of the bridge deck, and adopts an I-shaped or box-shaped section.

[0008] The above-mentioned fully prestressed steel-concrete composite continuous beam bridge in the negative bending moment area, the negative bending moment area steel main beam comprises a negative bending moment area steel main beam top plate, a negative bending moment area steel main beam bottom plate, a negative bending moment area steel main beam web, a negative bending moment area steel main beam stiffening rib, a negative bending moment area steel main beam bolt, and a negative bending moment area steel main beam lock; the negative bending moment area steel main beam web is welded with the negative bending moment area steel main beam top plate and the negative bending moment area steel main beam bottom plate; the negative bending moment area steel main beam web, the negative bending moment area steel main beam top plate and the negative bending moment area steel main beam bottom plate are welded; A number of negative bending zone steel main beam stiffening ribs are arranged on the plate, a number of negative bending zone steel main beam bolts and negative bending zone steel main beam locks for connecting the negative bending zone steel-concrete composite bridge deck are welded on the negative bending zone steel main beam top plate, the negative bending zone steel main beam locks are arranged along the longitudinal length of the bridge, multiple locks are evenly arranged according to the width of the negative bending zone steel main beam top plate, and the negative bending zone steel main beam locks are symmetrically arranged about the cross-section center; the number and cross-section form of the negative bending zone steel main beam are consistent with those of the positive bending zone steel main beam.

[0009] For the above-mentioned fully prestressed steel-concrete composite continuous beam bridge in the negative bending moment zone, steel cross beams are arranged between two adjacent steel main beams in the positive bending moment zone and between two adjacent steel main beams in the negative bending moment zone. The steel cross beams are arranged every 3 to 8 meters. The steel cross beams are I-beams, box beams or trusses. The steel cross beams are welded or bolted to the web of the steel main beam in the positive bending moment zone or the web of the steel main beam in the negative bending moment zone.

[0010] The above-mentioned fully prestressed steel-concrete composite continuous beam bridge in the negative bending moment area, the steel-concrete composite bridge deck in the positive bending moment area includes a steel bottom formwork for the bridge deck in the positive bending moment area, longitudinal steel bars in the positive bending moment area, transverse steel bars in the positive bending moment area, and concrete in the positive bending moment area; the steel bottom formwork for the bridge deck in the positive bending moment area is a supporting platform for the concrete pouring construction formwork in the positive bending moment area, the steel bottom formwork for the bridge deck in the positive bending moment area includes a side steel bottom plate in the positive bending moment area, a middle steel bottom plate in the positive bending moment area, transverse ribs of the perforated plate in the positive bending moment area, bolts of the steel bottom plate in the positive bending moment area, and bolt fixing holes of the steel bottom plate in the positive bending moment area; two side steel bottom plates in the positive bending moment area are symmetrically arranged on both sides of the middle steel bottom plate in the positive bending moment area, and a plurality of transverse ribs of the perforated plate in the positive bending moment area are fixed parallel to each other. A number of positive moment zone steel bottom plate bolts are welded on the positive moment zone side steel bottom plate and the positive moment zone middle steel bottom plate, positive moment zone steel bottom plate bolt fixing holes are opened on the positive moment zone side steel bottom plate and the positive moment zone middle steel bottom plate, the positive moment zone steel bottom plate bolt fixing holes correspond to the positions of the welding bolts of the positive moment zone steel main beam, a plurality of positive moment zone longitudinal steel bars are sequentially arranged on the transverse ribs of the positive moment zone hole plate, a plurality of positive moment zone transverse steel bars are sequentially arranged on the positive moment zone longitudinal steel bars, and the steel-concrete composite section beam of the positive moment zone steel main beam and the positive moment zone steel-concrete composite bridge deck is formed by pouring positive moment zone concrete.

[0011] The above-mentioned fully prestressed steel-concrete composite continuous beam bridge in the negative bending moment area, the steel-concrete composite bridge deck in the negative bending moment area includes a steel bottom formwork for the bridge deck in the negative bending moment area, longitudinal steel bars in the negative bending moment area, transverse steel bars in the negative bending moment area, concrete in the negative bending moment area, a longitudinal prestressing system, a built-in wet joint prestressing system, a built-in wet joint, a sealing rubber tube, and a sealing rubber tube slurry; The steel bottom formwork of the bridge deck in the negative bending moment area includes the side steel bottom plate in the negative bending moment area, the middle steel bottom plate in the negative bending moment area, the channel beam, the transverse rib of the perforated plate in the negative bending moment area, the steel bottom plate bolts in the negative bending moment area, the steel bottom plate lock mouth in the negative bending moment area, and the polytetrafluoroethylene plate of the steel bottom plate in the negative bending moment area; The built-in wet joint comprises a built-in wet joint space, a built-in wet joint slurry poured in the built-in wet joint space, and a built-in wet joint prestressing system arranged in the built-in wet joint slurry; The trough beam comprises a trough plate, a trough beam stiffening rib, a trough plate top bolt, and a trough plate bottom bolt, and the trough beam stiffening rib, the trough plate top bolt, and the trough plate bottom bolt are welded to the trough plate; The trough beam stiffening ribs include trough beam stiffening rib plates, trough beam stiffening rib openings arranged on the trough beam stiffening rib plates, and trough beam stiffening rib locks arranged on the trough beam stiffening rib plates; the trough beam stiffening rib openings and the built-in wet joint slurry form a PBL shear connection key, the trough beam stiffening rib locks are connected to the corresponding positions of the negative moment zone steel main beam locks, the trough beam stiffening rib locks are arranged along the longitudinal bridge length, a sealing rubber tube is arranged in the trough beam stiffening rib locks, and a sealing rubber tube slurry is formed after grouting, so that the trough beam is closely connected to the top plate of the steel main beam in the negative moment zone, and the trough beam stiffening ribs are used to separate the built-in wet joint space to form a plurality of nearly square spaces, and a number of paths are arranged according to the width of the top plate of the steel main beam in the negative moment zone; Two negative moment zone side steel bottom plates are symmetrically arranged on both sides of the negative moment zone middle steel bottom plate. Both ends of the negative moment zone middle steel bottom plate are connected to the two negative moment zone side steel bottom plates on both sides through a trough beam. The trough beam is welded to the negative moment zone side steel bottom plates and the negative moment zone middle steel bottom plate. The top surfaces of the three are flush. Several negative moment zone perforated plate transverse ribs are arranged in parallel and welded on the top surfaces of the three to jointly form a load-bearing structure and a template for pouring concrete in the negative moment zone. A negative moment zone steel bottom plate lock is arranged at the connection between the negative moment zone middle steel bottom plate and the trough beam. A negative moment zone steel bottom plate polytetrafluoroethylene plate is arranged at the bottom of the negative moment zone steel bottom plate lock; the negative moment zone steel bottom plate bolts are welded to the negative moment zone side steel bottom plates and the negative moment zone middle steel bottom plates. A plurality of longitudinal steel bars in the negative bending moment area and a plurality of longitudinal prestressing systems are sequentially arranged on the transverse ribs of the perforated plate in the negative bending moment area, a plurality of transverse steel bars in the negative bending moment area are sequentially arranged on the longitudinal steel bars in the negative bending moment area, the locking mouth of the steel bottom plate in the negative bending moment area is connected with the locking mouth of the steel main beam in the negative bending moment area at the corresponding position, the locking mouth of the steel bottom plate in the negative bending moment area is arranged along the longitudinal length of the bridge, a sealing rubber tube is arranged in the locking mouth of the steel bottom plate in the negative bending moment area, and a sealing rubber tube slurry is formed after grouting, which connects the steel-concrete composite bridge deck in the negative bending moment area and the steel main beam in the negative bending moment area as a whole, and forms a built-in wet joint space, the polytetrafluoroethylene plate of the steel bottom plate in the negative bending moment area is a sliding block when installing the steel bottom formwork of the bridge deck in the negative bending moment area, the longitudinal prestressing system and the built-in wet joint prestressing system are respectively used to apply the prestress of the negative bending moment area concrete and the built-in wet joint slurry to form full prestressed concrete in the longitudinal direction of the negative bending moment area.

[0012] The above-mentioned fully prestressed steel-concrete composite continuous beam bridge in the negative bending moment area, the longitudinal prestressing system includes longitudinal prestressed channels, longitudinal prestressed tendons, prestressed channel slurry, prestressed tendon anchors, and prestressed channel grouting holes; the longitudinal prestressed channels are evenly arranged in the steel-concrete composite bridge deck in the negative bending moment area, and pass through the transverse ribs of the perforated plate in the negative bending moment area, the size of the openings of the transverse ribs of the perforated plate in the negative bending moment area meets the arrangement requirements of the longitudinal prestressed channels, longitudinal prestressed tendons are arranged in the longitudinal prestressed channels, the longitudinal prestressed tendons are fixed in the longitudinal prestressed channels by prestressed tendon anchors, prestressed channel slurry is poured between the longitudinal prestressed tendons and the longitudinal prestressed channels, and prestressed channel grouting holes are arranged on the prestressed tendon anchors; the longitudinal prestressed channels use metal bellows or plastic bellows, the longitudinal prestressed tendons use steel strands, the prestressed tendon anchors use clip anchors, and micro-expansive cement mortar is used for grouting.

[0013] The above-mentioned fully prestressed steel-concrete composite continuous beam bridge in the negative bending moment zone, the built-in wet joint prestressing system includes high-strength steel wire bundles, pier head anchor cups, tensioning screws, anchor nuts, anchor plates, anchor plate fixing frames, and sealing bolts; The anchor plate includes an anchor plate end plate, an anchor plate side plate, an anchor plate tensioning screw sleeve, an anchor plate grouting hole, an anchor plate exhaust hole, an anchor plate tensioning screw hole, an anchor plate sealing ring, and a tensioning screw sealing ring; The high-strength steel wire bundle is composed of multiple high-strength steel wires. The high-strength steel wire bundle is formed into a bundle through the pier head anchor cup. The pier head anchor cup is a hollow metal cylinder with threads inside, which is used in conjunction with the tensioning screw. The tensioning screw has threads at both ends and no threads in the middle. One end of the tensioning screw is connected to the pier head anchor cup, and the other end of the tensioning screw is connected to the anchor nut. The connection length is adjusted through the threaded section of the tensioning screw, which is used for tensioning the high-strength steel wire bundle. The anchor plate and anchor plate fixing frame are used in combination. The cross-section of the opening in the anchor plate fixing frame is consistent with the cross-section size of the anchor plate end plate, so that the anchor plate can be installed in the anchor plate fixing frame. The anchor plate fixing frame is adapted to the built-in wet joint and has the same shape as the groove plate. After the tensioning of the longitudinal prestressed tendons is completed, the top surface and two side surfaces of the anchor plate fixing frame are welded to the groove plate respectively, and the bottom surface of the anchor plate fixing frame is welded to the top plate of the steel main beam in the positive bending moment zone. Anchor plate grouting holes, anchor plate exhaust holes, and anchor plate tensioning screw holes are opened on the anchor plate end plates. The anchor plate grouting holes and anchor plate exhaust holes are closed with sealing bolts. Anchor plate sealing rings are arranged at the ends of the anchor plate side plates. The anchor plate tensioning screw sleeve is a hollow cylinder. The anchor plate tensioning screw hole in the middle of the anchor plate tensioning screw sleeve has the same diameter as the tensioning screw. One end of the anchor plate tensioning screw sleeve is welded to the anchor plate end plate, and a tensioning screw sealing ring is arranged at the other end of the anchor plate tensioning screw sleeve.

[0014] The above-mentioned fully prestressed steel-concrete composite continuous beam bridge in the negative bending moment zone, the post-cast steel-concrete composite bridge deck includes a post-cast steel deck bottom formwork, post-cast longitudinal steel bars, post-cast transverse steel bars, and post-cast concrete; the post-cast steel deck bottom formwork includes a post-cast edge steel bottom plate, a post-cast middle steel bottom plate, a post-cast perforated plate transverse ribs, post-cast steel bottom plate bolts, and post-cast steel bottom plate bolt fixing holes; the structure of the post-cast steel-concrete composite bridge deck is the same as that of the steel-concrete composite bridge deck in the positive bending moment zone. According to construction needs, some post-cast perforated plate transverse ribs and post-cast steel bottom plate bolts will be welded after the construction of the longitudinal prestressing system and the built-in wet joint prestressing system is completed.

[0015] A construction method for a fully prestressed steel-concrete composite continuous beam bridge in a negative bending moment zone comprises the following steps: Step 1: Install the steel main beam and steel cross beam, splice and install the steel main beam in the positive bending moment area and the steel main beam in the negative bending moment area on the bracket, and install the steel cross beam between the steel main beams, using welding or bolting to install, and remove the bracket after installation; Step 2: Install sealing rubber strips on the steel main beams in the positive bending moment area except for the post-cast steel-concrete composite bridge deck area; Step 3: Install a sealing rubber tube in the locking mouth of the steel main beam in the negative bending moment area to seal the locking mouth of the steel bottom plate in the negative bending moment area and the locking mouth of the channel beam stiffening rib; Step 4: Lay high-strength steel wire bundles with pier head anchor cups and tensioning screws on the steel main beam in the negative bending moment area; Step 5: Install the steel bottom formwork of the bridge deck in the positive bending moment area, use a crane to hoist the steel bottom formwork of the bridge deck in the positive bending moment area onto the steel main beam in the positive bending moment area, and then fix it with welding bolts of the steel main beam in the positive bending moment area; Step 6: Install the steel bottom formwork of the bridge deck in the negative bending area, install a winch on the installed steel bottom formwork of the bridge deck in the positive bending area, hoist the steel bottom formwork of the bridge deck in the negative bending area to the steel main beam in the positive bending area corresponding to the position of the post-cast steel-concrete composite bridge deck, and use the winch to drag it, combined with the friction of the polytetrafluoroethylene plate of the steel bottom plate of the negative bending area on the steel bottom formwork of the bridge deck in the negative bending area, to install each section of the steel bottom formwork of the bridge deck in the negative bending area in place in sequence. After installation, remove the winch, and then weld the contact surfaces of each section: the side steel bottom plate of the negative bending area, the middle steel bottom plate of the negative bending area, and the trough plate; Step 7: Install sealing rubber strips on the steel main beams in the positive bending moment area of ​​the post-cast steel-concrete composite bridge deck; Step 8: Install the post-casting belt bridge deck steel bottom formwork, use a crane to hoist the post-casting belt bridge deck steel bottom formwork to the steel main beam in the positive bending moment area, and then fix it through the welding bolts of the steel main beam in the positive bending moment area. The post-casting belt bridge deck steel bottom formwork is used as a working platform for tensioning the prestress of the steel-concrete composite bridge deck in the negative bending moment area. According to the tensioning construction requirements, some post-casting belt perforated plate transverse ribs and post-casting belt steel bottom plate bolts are welded after the prestressing construction is completed; Step 9: Tie the longitudinal reinforcement and transverse reinforcement in the positive bending moment area to the steel bottom formwork of the bridge deck in the positive bending moment area, pour the concrete in the positive bending moment area and maintain it; Step 10: Arrange longitudinal prestressed holes on the steel bottom formwork of the bridge deck in the negative bending moment area, tie the longitudinal steel bars in the negative bending moment area and the transverse steel bars in the negative bending moment area, pour the concrete in the negative bending moment area and maintain it; Step 11: When the concrete strength in the negative moment zone reaches more than 90%, the longitudinal prestressed tendons in the steel-concrete composite bridge deck in the negative moment zone are tensioned, anchored by prestressed tendon anchors, and the longitudinal prestressed channels are grouted through the prestressed channel grouting holes; Step 12: Grout the sealing rubber tube on the steel main beam in the negative bending moment area, so that the trough plate, the side steel bottom plate in the negative bending moment area, the middle steel bottom plate in the negative bending moment area and the top plate of the steel main beam in the negative bending moment area form a closed section. At the same time, the trough beam stiffening rib is also connected to the top plate of the steel main beam in the negative bending moment area; Step 13: Install the built-in wet joint anchor, weld the anchor plate fixing frame to the channel plate and the top plate of the steel main beam in the negative bending moment area, and form a built-in wet joint space in the steel box space; Step 14: Grout the built-in wet joint space through the anchor plate grouting holes on the anchor plate. After the grouting is completed, seal the anchor plate grouting holes and the anchor plate exhaust holes with sealing bolts; Step 15: Before the initial setting of the built-in wet joint slurry, the high-strength steel wire bundle is tensioned and anchored with anchor nuts; Step 16: Weld the post-cast strip perforated plate transverse ribs and post-cast strip steel bottom plate bolts on the post-cast strip steel-concrete composite bridge deck, tie the post-cast strip longitudinal steel bars and post-cast strip transverse steel bars, pour the post-cast strip concrete and maintain.

[0016] The beneficial effects of the present invention are: 1. The present invention significantly improves the effective prestress of concrete in the negative bending zone of the continuous composite beam, and can avoid cracking of the concrete in the negative bending zone. The steel bottom plate in the negative bending zone serves as a casting template for the concrete in the negative bending zone of the bridge deck, and is directly supported on the steel main beam. When the longitudinal prestressed tendons in the bridge deck are tensioned, the steel main beam only serves as a support and does not participate in sharing the prestress, thereby significantly improving the effective precompression stress of the concrete in the negative bending zone.

[0017] 2. The present invention significantly improves the bonding stiffness of the steel main beam and the steel-concrete composite bridge deck in the negative bending zone. a) The internal wet joint is formed by the steel bottom plate in the negative bending zone. After the longitudinal prestressed tendons of the bridge deck are tensioned, the internal wet joint concrete is poured. The entire steel-concrete composite bridge deck in the negative bending zone has no grouting holes or vents. There is no problem of corrosion of the steel bars, bolts, and steel main beams in the concrete due to cracking of the bridge deck. The internal wet joint concrete is connected to the steel bottom plate in the negative bending zone and the top plate of the steel box beam through the upper and lower bolts, and the connection is firm. b) The internal wet joint is made It is a closed steel box structure and a built-in wet joint prestressing system is designed. Before the wet joint slurry is initially set, it is prestressed. At this time, effective connection stiffness has not yet been formed between the wet joint slurry and the studs. The prestress is only applied to the wet joint slurry, which significantly increases the prestress of the slurry in the built-in wet joints, so that the entire bridge deck concrete in the negative bending moment area is fully prestressed concrete and will not crack. In addition, the slurry in the built-in wet joints is in a three-dimensional stress state with good stress performance, which further strengthens the connection stiffness of the steel-concrete composite bridge deck and the steel main beam. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of a steel-concrete composite three-span continuous beam according to an embodiment of the present invention.

[0019] Figure 2 It is a schematic structural diagram of the steel main beam in the positive bending moment zone of the present invention.

[0020] Figure 3 It is a schematic diagram of the cross-sectional structure of the steel main beam in the positive bending moment zone of the present invention.

[0021] Figure 4 It is a schematic structural diagram of the steel main beam in the negative bending moment area of ​​the present invention.

[0022] Figure 5 It is a schematic diagram of the cross-sectional structure of the steel main beam in the negative bending moment area of ​​the present invention.

[0023] Figure 6 It is a schematic structural diagram of the steel-concrete composite bridge deck in the positive moment zone of the present invention.

[0024] Figure 7 It is a schematic structural diagram of the steel bottom formwork of the bridge deck in the positive bending moment area of ​​the present invention.

[0025] Figure 8It is a schematic diagram of the cross-sectional structure of the steel bottom formwork of the bridge deck in the positive bending moment area of ​​the present invention.

[0026] Fig. 9 It is a schematic structural diagram of the post-cast steel-concrete composite bridge deck of the present invention.

[0027] Fig.10 It is a schematic structural diagram of the steel bottom formwork of the post-cast bridge deck of the present invention.

[0028] Fig.11 It is a schematic diagram of the cross-sectional structure of the steel bottom formwork of the post-cast bridge deck of the present invention.

[0029] Fig.12 It is a schematic structural diagram of the steel-concrete composite bridge deck in the negative bending moment zone of the present invention.

[0030] Fig.13 It is a schematic structural diagram of the steel bottom formwork of the bridge deck in the negative bending moment area of ​​the present invention.

[0031] Fig.14 It is a schematic diagram of the cross-sectional structure of the steel bottom formwork of the bridge deck in the negative bending moment area of ​​the present invention.

[0032] Fig.15 It is a schematic diagram of the exploded parts of the trough beam of the present invention.

[0033] Fig.16 It is a schematic diagram of the bottom view of the trough beam structure of the present invention.

[0034] Fig.17 It is a schematic diagram of the connection between the steel-concrete composite bridge deck in the negative bending moment area and the steel main beam in the negative bending moment area of ​​the present invention.

[0035] Fig.18 for Fig.17 Magnified view of area A.

[0036] Fig.19 Before grouting the rubber tube Fig.17 Magnified view of area B.

[0037] Fig. 20 After grouting the rubber tube Fig.17 Magnified view of area B.

[0038] Fig.21 It is a schematic structural diagram of the built-in wet joint prestressing system of the present invention.

[0039] Fig. 22 It is a front view of the anchor plate and the anchor plate fixing frame of the present invention.

[0040] Fig.23 It is a rear view of the anchor plate and the anchor plate fixing frame of the present invention.

[0041] Fig.24 This is a schematic diagram of the built-in wet joint prestressing system of the present invention before tensioning.

[0042] Fig.25 It is a schematic diagram of the built-in wet joint prestressing system of the present invention after tensioning.

[0043] Fig.26 This is a schematic diagram of the installation of the built-in wet joint prestressing system of the present invention before tensioning. DETAILED DESCRIPTION

[0044] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0045] like Figure 1 As shown, a fully prestressed steel-concrete composite continuous beam bridge in a negative bending zone comprises a steel main beam 1 in a positive bending zone, a steel main beam 2 in a negative bending zone, a steel cross beam 3, a steel-concrete composite bridge deck in a positive bending zone 4, a steel-concrete composite bridge deck in a negative bending zone 5 and a post-cast steel-concrete composite bridge deck 6. The steel main beams 1 in the positive bending zone and the steel main beams 2 in the negative bending zone are alternately arranged and sequentially spliced ​​to form an integral main beam. The integral main beam is installed on a bridge pier 8 through a support 7. The steel-concrete composite bridge deck 4 in the positive bending zone is installed on a bridge pier 8. On the positive bending zone steel main beam 1, the negative bending zone steel-concrete composite bridge deck 5 is installed on the negative bending zone steel main beam 2, and a post-cast strip steel-concrete composite bridge deck 6 is arranged at a position between the positive bending zone steel-concrete composite bridge deck 4 and the negative bending zone steel-concrete composite bridge deck 5 on the positive bending zone steel main beam 1; the negative bending zone bridge deck steel bottom formwork in the negative bending zone steel-concrete composite bridge deck 5 and the negative bending zone steel main beam top plate 21 in the negative bending zone steel main beam 2 form a built-in wet joint 57, and the first tension is applied during construction. The longitudinal prestressed tendons 552 in the steel-concrete composite bridge deck 5 in the negative bending moment area are pulled. At this time, the steel main beam 2 in the negative bending moment area serves as a supporting platform for the steel-concrete composite bridge deck 5 in the negative bending moment area, and does not affect the application of the concrete prestress of the bridge deck; then the built-in wet joint space 571 is poured. The built-in wet joint space 571 is a closed section. The built-in wet joint prestressing system 56 makes the built-in wet joint 57 a closed space. Before the built-in wet joint slurry 572 begins to set, the built-in wet joint slurry 571 is poured. The high-strength steel wire bundle 561 in the joint prestressing system 56 is tensioned. At this time, the built-in wet joint slurry 572 and the top surface grooved plate bottom bolts 5134 and the bottom surface negative bending moment area steel main beam bolts 25 do not form an effective connection stiffness. The prestress tensioned by the high-strength steel wire bundle 561 only acts on the built-in wet joint slurry 572, forming a fully prestressed built-in wet joint slurry 572, so that the steel-concrete composite bridge deck 5 in the negative bending moment area is in a fully prestressed concrete stress state in the longitudinal direction of the bridge.

[0046] like Figure 2 , Figure 3As shown, the positive bending zone steel main beam 1 comprises a positive bending zone steel main beam top plate 11, a positive bending zone steel main beam bottom plate 12, a positive bending zone steel main beam web 13, a positive bending zone steel main beam stiffening rib 14, a positive bending zone steel main beam stud 15, a positive bending zone steel main beam welding bolt 16, and a sealing rubber strip 17; the positive bending zone steel main beam web 13 is welded with the positive bending zone steel main beam top plate 11 and the positive bending zone steel main beam bottom plate 12, and the positive bending zone steel main beam web 13, the positive bending zone steel main beam top plate 11 and the positive bending zone steel main beam A plurality of positive bending zone steel main beam stiffening ribs 14 are arranged on the beam bottom plate 12, a plurality of positive bending zone steel main beam bolts 15 are welded on the positive bending zone steel main beam top plate 11, a plurality of positive bending zone steel main beam welding bolts 16 for fixing the positive bending zone steel-concrete composite bridge deck 4 are arranged on both sides of the positive bending zone steel main beam top plate 11, and a full-length sealing rubber strip 17 is arranged on both sides of the positive bending zone steel main beam top plate 11 to prevent leakage of concrete when pouring the bridge deck; the positive bending zone steel main beam 1 is provided with multiple strips according to the width of the bridge deck and adopts a box section.

[0047] like Figure 4 , Figure 5 As shown, the negative bending zone steel main beam 2 includes a negative bending zone steel main beam top plate 21, a negative bending zone steel main beam bottom plate 22, a negative bending zone steel main beam web 23, a negative bending zone steel main beam stiffening rib 24, a negative bending zone steel main beam bolt 25, and a negative bending zone steel main beam lock 26; the negative bending zone steel main beam web 23 is welded with the negative bending zone steel main beam top plate 21 and the negative bending zone steel main beam bottom plate 22, and the negative bending zone steel main beam web 23, the negative bending zone steel main beam top plate 21 and the negative bending zone steel main beam bottom plate 22 are provided A plurality of negative bending zone steel main beam stiffening ribs 24 are provided, a plurality of negative bending zone steel main beam bolts 25 and negative bending zone steel main beam locks 26 for connecting the negative bending zone steel-concrete composite bridge deck 5 are welded on the negative bending zone steel main beam top plate 21, the negative bending zone steel main beam locks 26 are arranged along the longitudinal length of the bridge, a plurality of negative bending zone steel main beam locks 26 are evenly arranged according to the width of the negative bending zone steel main beam top plate 21, and the negative bending zone steel main beam locks 26 are symmetrically arranged about the cross-section center; the number of negative bending zone steel main beams 2 and the cross-section form are consistent with those of the positive bending zone steel main beam 1.

[0048] Steel cross beams 3 are arranged between two adjacent steel main beams 1 in the positive bending moment area and between two adjacent steel main beams 2 in the negative bending moment area. The steel cross beams 3 are arranged every 3 to 8 meters. The steel cross beams 3 are I-beams, box beams or trusses. The steel cross beams 3 are welded to the webs 13 of the steel main beams in the positive bending moment area or the webs 23 of the steel main beams in the negative bending moment area.

[0049] like Figure 6-Figure 8As shown, the positive bending zone steel-concrete composite bridge deck 4 includes a positive bending zone bridge deck steel bottom formwork 41, a positive bending zone longitudinal steel bar 42, a positive bending zone transverse steel bar 43, and a positive bending zone concrete 44; the positive bending zone bridge deck steel bottom formwork 41 is a supporting platform for pouring a construction template for the positive bending zone concrete 44, and the positive bending zone bridge deck steel bottom formwork 41 includes a positive bending zone edge steel bottom plate 411, a positive bending zone middle steel bottom plate 412, a positive bending zone perforated plate transverse rib 413, a positive bending zone steel bottom plate bolt 414, and a positive bending zone steel bottom plate bolt fixing hole 415, two positive bending zone edge steel bottom plates 411 are symmetrically arranged on both sides of the positive bending zone middle steel bottom plate 412, and a plurality of positive bending zone perforated plate transverse ribs 413 are fixed parallel to each other on the positive bending zone edge steel bottom plates 411. 1 and the middle steel bottom plate 412 in the positive bending zone, a plurality of positive bending zone steel bottom plate bolts 414 are welded on the positive bending zone side steel bottom plate 411 and the middle steel bottom plate 412 in the positive bending zone, positive bending zone steel bottom plate bolt fixing holes 415 are opened on the positive bending zone side steel bottom plate 411 and the middle steel bottom plate 412 in the positive bending zone, the positive bending zone steel bottom plate bolt fixing holes 415 correspond to the positions of the positive bending zone steel main beam welding bolts 16, a plurality of positive bending zone longitudinal steel bars 42 are sequentially arranged on the positive bending zone perforated plate transverse ribs 413, a plurality of positive bending zone transverse steel bars 43 are sequentially arranged on the positive bending zone longitudinal steel bars 42, and a steel-concrete composite section beam of the positive bending zone steel main beam 1 and the positive bending zone steel-concrete composite bridge deck 4 is formed by pouring the positive bending zone concrete 44.

[0050] like Figure 12-Figure 20 As shown, the negative bending zone steel-concrete composite bridge deck 5 includes a negative bending zone bridge deck steel bottom form 51, a negative bending zone longitudinal steel bar 52, a negative bending zone transverse steel bar 53, a negative bending zone concrete 54, a longitudinal prestressing system 55, a built-in wet joint prestressing system 56, a built-in wet joint 57, a sealing rubber tube 58, and a sealing rubber tube slurry 59; The negative bending zone bridge deck steel bottom formwork 51 includes a negative bending zone side steel bottom plate 511, a negative bending zone middle steel bottom plate 512, a trough beam 513, a negative bending zone perforated plate transverse rib 514, a negative bending zone steel bottom plate bolt 515, a negative bending zone steel bottom plate lock 516, and a negative bending zone steel bottom plate polytetrafluoroethylene plate 517; The built-in wet joint 57 includes a built-in wet joint space 571, a built-in wet joint slurry 572 poured into the built-in wet joint space 571, and a built-in wet joint prestressing system 56 disposed in the built-in wet joint slurry 572; The trough beam 513 includes a trough plate 5131, a trough beam stiffening rib 5132, a trough plate top bolt 5133, and a trough plate bottom bolt 5134, and the trough beam stiffening rib 5132, the trough plate top bolt 5133, and the trough plate bottom bolt 5134 are welded to the trough plate 5131; The trough beam stiffening rib 5132 includes a trough beam stiffening rib plate 51321, a trough beam stiffening rib opening 51322 arranged on the trough beam stiffening rib plate 51321, and a trough beam stiffening rib lock 51323 arranged on the trough beam stiffening rib plate 51321; the trough beam stiffening rib opening 51322 and the built-in wet joint slurry 572 form a PBL shear connection key, and the trough beam stiffening rib lock 51323 and the corresponding position negative bending moment zone steel main beam lock 26 The trough beam stiffening rib lock 51323 is arranged along the longitudinal direction of the bridge. A sealing rubber tube 58 is arranged in the trough beam stiffening rib lock 51323. After grouting, a sealing rubber tube slurry 59 is formed, so that the trough beam 513 is tightly connected with the top plate 21 of the steel main beam in the negative bending moment area. The trough beam stiffening rib 5132 is used to separate the built-in wet joint space 571, so that it forms a plurality of nearly square spaces. A number of paths are arranged according to the width of the top plate 21 of the steel main beam in the negative bending moment area. Two negative moment zone side steel bottom plates 511 are symmetrically arranged on both sides of the negative moment zone middle steel bottom plate 512. Both ends of the negative moment zone middle steel bottom plate 512 are connected to the two negative moment zone side steel bottom plates 511 on both sides through a trough beam 513. The trough beam 513 is welded to the negative moment zone side steel bottom plates 511 and the negative moment zone middle steel bottom plate 512. The top surfaces of the three are flush. A number of negative moment zone perforated plate transverse ribs 514 are arranged in parallel and welded on the top surfaces of the three. The negative bending zone steel bottom plate 512 is connected to the trough beam 513 by a negative bending zone steel bottom plate lock 516, and a negative bending zone steel bottom plate polytetrafluoroethylene plate 517 is provided at the bottom of the negative bending zone steel bottom plate lock 516; the negative bending zone steel bottom plate bolts 515 are welded to the negative bending zone side steel bottom plate 511 and the negative bending zone middle steel bottom plate 512, and multiple negative bending zone longitudinal steel bars 52 and multiple The longitudinal prestressing system 55 is sequentially arranged on the transverse ribs 514 of the perforated plate in the negative bending moment area, and a plurality of transverse steel bars 53 in the negative bending moment area are sequentially arranged on the longitudinal steel bars 52 in the negative bending moment area. The steel bottom plate locking mouth 516 in the negative bending moment area is connected with the corresponding steel main beam locking mouth 26 in the negative bending moment area. The steel bottom plate locking mouth 516 in the negative bending moment area is arranged along the longitudinal length of the bridge. A sealing rubber tube 58 is arranged in the steel bottom plate locking mouth 516 in the negative bending moment area. After grouting, a sealing rubber tube slurry 59 is formed. The steel-concrete composite bridge deck 5 in the negative bending moment area and the steel main beam 2 in the negative bending moment area are connected as a whole to form a built-in wet joint space 571. The polytetrafluoroethylene plate 517 of the steel bottom plate in the negative bending moment area is a sliding block during the installation of the steel bottom formwork 51 of the bridge deck in the negative bending moment area. The longitudinal prestressing system 55 and the built-in wet joint prestressing system 56 are respectively used to apply prestress to the negative bending moment area concrete 54 and the built-in wet joint slurry 572 to form full prestressed concrete in the longitudinal direction of the negative bending moment area.

[0051] like Fig.18As shown, the longitudinal prestressing system 55 comprises a longitudinal prestressed channel 551, a longitudinal prestressed tendon 552, a prestressed channel slurry 553, a prestressed tendon anchor 554, and a prestressed channel grouting hole 555; the longitudinal prestressed channel 551 is evenly arranged in the steel-concrete composite bridge deck 5 in the negative bending moment area, and passes through the transverse rib 514 of the perforated plate in the negative bending moment area. The size of the opening of the transverse rib 514 of the perforated plate in the negative bending moment area meets the arrangement requirements of the longitudinal prestressed channel 551. The longitudinal prestressed channel 551 is provided with a longitudinal prestressed channel 552. Stress tendon 552, the longitudinal prestressed tendon 552 is fixed in the longitudinal prestressed channel 551 by the prestressed tendon anchor 554, the prestressed channel slurry 553 is poured between the longitudinal prestressed tendon 552 and the longitudinal prestressed channel 551, and the prestressed channel grouting hole 555 is arranged on the prestressed tendon anchor 554; the longitudinal prestressed channel 551 adopts a metal bellows or a plastic bellows, the longitudinal prestressed tendon 552 adopts a steel strand, the prestressed tendon anchor 554 adopts a clip anchor, and micro-expansive cement mortar is used for grouting.

[0052] like Figure 21-26 As shown, the built-in wet joint prestressing system 56 includes a high-strength steel wire bundle 561, a pier head anchor cup 562, a tensioning screw 563, an anchor nut 564, an anchor plate 565, an anchor plate fixing frame 566, and a sealing bolt 567; The anchor plate 565 includes an anchor plate end plate 5651, an anchor plate side plate 5652, an anchor plate tensioning screw sleeve 5653, an anchor plate grouting hole 5654, an anchor plate exhaust hole 5655, an anchor plate tensioning screw hole 5656, an anchor plate sealing ring 5657, and a tensioning screw sealing ring 5658; The high-strength steel wire bundle 561 is composed of a plurality of high-strength steel wires, which are formed into a bundle through the pier head anchor cup 562. The pier head anchor cup 562 is a hollow metal cylinder with threads inside, and is used in conjunction with the tensioning screw 563. The tensioning screw 563 has threads at both ends and a section in the middle without threads. One end of the tensioning screw 563 is connected to the pier head anchor cup 562, and the other end of the tensioning screw 563 is connected to the anchor nut 564. The connection length is adjusted by the threaded section of the tensioning screw 563, which is used for tensioning the high-strength steel wire bundle 561. The anchor plate 565 and the anchor plate fixing frame 566 are used in conjunction with each other. The cross-section of the opening in the anchor plate fixing frame 566 is consistent with the cross-section size of the anchor plate end plate 5651, so that the anchor plate 565 can be installed in the anchor plate fixing frame 566. The anchor plate fixing frame 566 is adapted to the built-in wet joint 57, and the shape is consistent with the groove plate 5131. After the tensioning of the longitudinal prestressed tendons 552 is completed, the top surface and two side surfaces of the anchor plate fixing frame 566 are respectively welded to the groove plate 5131, and the bottom surface of the anchor plate fixing frame 566 is welded to the top plate 11 of the steel main beam in the positive bending moment area. The anchor plate end plate 5651 is provided with an anchor plate grouting hole 5654, an anchor plate exhaust hole 5655, and an anchor plate tensioning screw hole 5656. The anchor plate grouting hole 5654 and the anchor plate exhaust hole 5655 are closed with a sealing bolt 567, and an anchor plate sealing ring 5657 is provided at the end of the anchor plate side plate 5652. Ring 5657 can withstand a pressure of not less than 20 MPa, and is used to seal the anchor plate side plate 5652 when the high-strength steel wire bundle 561 is tensioned; the anchor plate tensioning screw sleeve 5653 is a hollow cylinder, and the anchor plate tensioning screw hole 5656 in the middle of the anchor plate tensioning screw sleeve 5653 has the same diameter as the tensioning screw 563, one end of the anchor plate tensioning screw sleeve 5653 is welded to the anchor plate end plate 5651, and a tensioning screw sealing ring 5658 is arranged on the other end of the anchor plate tensioning screw sleeve 5653, which can withstand a pressure of not less than 20 MPa and is used to seal the anchor plate tensioning screw sleeve 5653 when the high-strength steel wire bundle 561 is tensioned. When the high-strength steel wire bundle 561 is tensioned, the position of the tensioning screw 563 should be adjusted to ensure that the tensioning screw sealing ring 5658 is always in contact with the non-threaded position of the tensioning screw 563 to prevent leakage during the tensioning process.

[0053] like Figure 9-11 As shown, the post-cast strip steel-concrete composite bridge deck 6 includes a post-cast strip bridge deck steel bottom formwork 61, a post-cast strip longitudinal steel bar 62, a post-cast strip transverse steel bar 63, and a post-cast strip concrete 64; the post-cast strip bridge deck steel bottom formwork 61 includes a post-cast strip edge steel bottom plate 611, a post-cast strip middle steel bottom plate 612, a post-cast strip perforated plate transverse rib 613, a post-cast strip steel bottom plate bolt 614, and a post-cast strip steel bottom plate bolt fixing hole 615; the structure of the post-cast strip steel-concrete composite bridge deck 6 is the same as that of the steel-concrete composite bridge deck 4 in the positive bending moment zone. According to construction needs, some of the post-cast strip perforated plate transverse rib 613 and the post-cast strip steel bottom plate bolt 614 are welded after the construction of the longitudinal prestressing system 55 and the built-in wet joint prestressing system 56 is completed.

[0054] A construction method for a fully prestressed steel-concrete composite continuous beam bridge in a negative bending moment zone comprises the following steps: Step 1: Install the steel main beam and the steel cross beam 3, splice and install the steel main beam 1 in the positive bending moment area and the steel main beam 2 in the negative bending moment area on the bracket, and install the steel cross beam 3 between the steel main beams, and install them by welding or bolting. After installation, remove the bracket; Step 2: Install the sealing rubber strip 17 on the steel main beam 1 in the positive bending moment area except the area of ​​the post-cast steel-concrete composite bridge deck 6; Step 3: Install a sealing rubber tube 58 in the negative bending moment area steel main beam lock 26 for sealing connection with the negative bending moment area steel bottom plate lock 516 and the channel beam stiffening rib lock 51323; Step 4: Lay out a high-strength steel wire bundle 561 with a pier head anchor cup 562 and a tensioning screw 563 on the steel main beam 2 in the negative bending moment area; Step 5: Install the positive bending moment area bridge deck steel bottom formwork 41, hoist the positive bending moment area bridge deck steel bottom formwork 41 onto the positive bending moment area steel main beam 1 by a crane, and then fix it by welding bolts 16 of the positive bending moment area steel main beam; Step 6: Install the steel bottom formwork 51 of the bridge deck in the negative bending zone, install a winch on the installed steel bottom formwork 41 of the bridge deck in the positive bending zone, hoist the steel bottom formwork 51 of the bridge deck in the negative bending zone to the steel main beam 1 of the positive bending zone corresponding to the position of the post-cast steel-concrete composite bridge deck 6, and install the sections of the steel bottom formwork 51 of the bridge deck in the negative bending zone in sequence by dragging with the winch and combining the friction of the polytetrafluoroethylene plate 517 of the steel bottom plate of the bridge deck in the negative bending zone on the steel bottom formwork 51 of the bridge deck in the negative bending zone. After the installation, remove the winch, and then weld the contact surfaces of the sections: the side steel bottom plate 511 of the negative bending zone, the middle steel bottom plate 512 of the negative bending zone, and the grooved plate 5131; Step 7: Install the sealing rubber strip 17 on the steel main beam 1 in the positive bending moment area of ​​the post-cast steel-concrete composite bridge deck 6; Step 8: Install the post-casting belt bridge deck steel bottom formwork 61, hoist the post-casting belt bridge deck steel bottom formwork 61 onto the positive bending moment area steel main beam 1 by a crane, and then fix it by welding bolts 16 of the positive bending moment area steel main beam. The post-casting belt bridge deck steel bottom formwork 61 is used as a working platform for tensioning the prestress of the steel-concrete composite bridge deck 5 in the negative bending moment area. According to the tensioning construction requirements, some post-casting belt perforated plate transverse ribs 613 and post-casting belt steel bottom plate bolts 614 are welded after the prestressing construction is completed; Step 9: Tie the longitudinal reinforcement 42 and the transverse reinforcement 43 in the positive bending moment area to the steel bottom formwork 41 in the positive bending moment area, pour the concrete 44 in the positive bending moment area and maintain the concrete; Step 10: Arrange longitudinal prestressed ducts 551 on the bottom steel formwork 51 of the bridge deck in the negative bending moment area, tie the longitudinal steel bars 52 and the transverse steel bars 53 in the negative bending moment area, pour the concrete 54 in the negative bending moment area and maintain it; Step 11: When the strength of the concrete 54 in the negative bending zone reaches more than 90%, the longitudinal prestressed tendons 552 in the steel-concrete composite bridge deck 5 in the negative bending zone are tensioned, anchored by the prestressed tendon anchor 554, and the longitudinal prestressed duct 551 is grouted through the prestressed duct grouting hole 555; Step 12: Grouting the sealing rubber tube 58 on the negative moment zone steel main beam 2, so that the trough plate 5131, the negative moment zone side steel bottom plate 511, the negative moment zone middle steel bottom plate 512 and the negative moment zone steel main beam top plate 21 form a closed section, and at the same time, the trough beam stiffening rib 5132 is also connected to the negative moment zone steel main beam top plate 21 as a whole; Step 13: Install the built-in wet joint anchor, weld the anchor plate fixing frame 566 to the channel plate 5131 and the top plate 21 of the steel main beam in the negative bending moment area, and form a built-in wet joint space 571 of the steel box space; Step 14: Grouting is performed on the built-in wet joint space 571 through the anchor plate grouting hole 5654 on the anchor plate 565. After the grouting is completed, the anchor plate grouting hole 5654 and the anchor plate exhaust hole 5655 are sealed with a sealing bolt 567; Step 15: Before the built-in wet joint slurry 572 initially sets, the high-strength steel wire bundle 561 is tensioned and anchored with an anchor nut 564; Step 16: weld the post-cast strip perforated plate transverse ribs 613 and the post-cast strip steel bottom plate bolts 614 on the post-cast strip steel-concrete composite bridge deck 6, tie the post-cast strip longitudinal steel bars 62 and the post-cast strip transverse steel bars 63, pour the post-cast strip concrete 64 and maintain.

Claims

1. A fully prestressed steel-concrete composite continuous beam bridge in a negative bending moment area, comprising a steel main beam in a positive bending moment area, a steel main beam in a negative bending moment area, a steel cross beam, a steel-concrete composite bridge deck in a positive bending moment area, a steel-concrete composite bridge deck in a negative bending moment area and a post-cast steel-concrete composite bridge deck, characterized in that: The positive moment zone steel main beam and the negative moment zone steel main beam are arranged alternately and spliced ​​in sequence to form an integral main beam, the integral main beam is installed on the bridge pier through a support, the positive moment zone steel-concrete composite bridge deck is installed on the positive moment zone steel main beam, and the negative moment zone steel-concrete composite bridge deck is installed on the negative moment zone steel main beam, and a post-cast steel-concrete composite bridge deck is arranged at a position between the positive moment zone steel-concrete composite bridge deck and the negative moment zone steel-concrete composite bridge deck on the positive moment zone steel main beam; the negative moment zone bridge deck steel bottom formwork in the negative moment zone steel-concrete composite bridge deck and the negative moment zone steel main beam top plate in the negative moment zone steel main beam form a built-in wet joint, and the longitudinal prestressed tendons in the negative moment zone steel-concrete composite bridge deck are tensioned first during construction. At this time, the negative moment zone steel main beam The beam serves as a supporting platform for the steel-concrete composite bridge deck in the negative bending moment area and does not affect the application of prestressing of the bridge deck concrete. Then, the built-in wet joint space is poured. The built-in wet joint space is a closed section. The built-in wet joint prestressing system makes the built-in wet joint a closed space. Before the initial setting of the built-in wet joint slurry, the high-strength steel wire bundles in the built-in wet joint prestressing system are tensioned. At this time, the built-in wet joint slurry and the top surface grooved plate bottom bolts and the bottom surface negative bending moment area steel main beam bolts do not form an effective connection stiffness. The prestress tensioned by the high-strength steel wire bundle only acts on the built-in wet joint slurry, forming a fully prestressed built-in wet joint slurry, so that the steel-concrete composite bridge deck in the negative bending moment area is in a fully prestressed concrete stress state in the longitudinal direction of the bridge.

2. The fully prestressed steel-concrete composite continuous beam bridge in the negative moment zone according to claim 1 is characterized in that: The positive bending moment zone steel main beam comprises a positive bending moment zone steel main beam top plate, a positive bending moment zone steel main beam bottom plate, a positive bending moment zone steel main beam web plate, a positive bending moment zone steel main beam stiffening rib, a positive bending moment zone steel main beam bolt, a positive bending moment zone steel main beam welding bolt, and a sealing rubber strip; the positive bending moment zone steel main beam web plate is welded with the positive bending moment zone steel main beam top plate and the positive bending moment zone steel main beam bottom plate, and some The steel main beams in the positive bending moment area of ​​the trunk road are reinforced with stiffening ribs, a number of steel main beam bolts in the positive bending moment area are welded on the top plates of the steel main beams in the positive bending moment area, a number of steel main beam welding bolts in the positive bending moment area for fixing the steel-concrete composite bridge deck in the positive bending moment area are arranged on both sides of the top plates of the steel main beams in the positive bending moment area, and a full-length sealing rubber strip is arranged on both sides of the top plates of the steel main beams in the positive bending moment area to prevent leakage when pouring bridge deck concrete; the steel main beams in the positive bending moment area are arranged with multiple strips according to the width of the bridge deck, and adopt I-shaped or box-shaped sections.

3. The fully prestressed steel-concrete composite continuous beam bridge in the negative bending zone according to claim 2 is characterized in that: The negative bending moment area steel main beam comprises a negative bending moment area steel main beam top plate, a negative bending moment area steel main beam bottom plate, a negative bending moment area steel main beam web plate, a negative bending moment area steel main beam stiffening rib, a negative bending moment area steel main beam bolt, and a negative bending moment area steel main beam lock; the negative bending moment area steel main beam web plate is welded with the negative bending moment area steel main beam top plate and the negative bending moment area steel main beam bottom plate, and a plurality of negative bending moment lines are arranged on the negative bending moment area steel main beam web plate, the negative bending moment area steel main beam top plate and the negative bending moment area steel main beam bottom plate The steel main beam in the negative moment area is reinforced with stiffening ribs, and a number of negative moment area steel main beam bolts and negative moment area steel main beam locks for connecting the steel-concrete composite bridge deck in the negative moment area are welded on the top plate of the steel main beam in the negative moment area. The negative moment area steel main beam locks are arranged along the longitudinal length of the bridge, and multiple locks are evenly arranged according to the width of the top plate of the steel main beam in the negative moment area. The negative moment area steel main beam locks are symmetrically arranged about the center of the cross-section; the number of steel main beams in the negative moment area and the cross-sectional form are consistent with those of the steel main beams in the positive moment area.

4. The fully prestressed steel-concrete composite continuous beam bridge in the negative moment zone according to claim 3 is characterized in that: Steel cross beams are set between two adjacent steel main beams in the positive bending moment zone and between two adjacent steel main beams in the negative bending moment zone. The steel cross beams are arranged every 3 to 8 meters. The steel cross beams are I-beams, box beams or trusses. The steel cross beams are welded or bolted to the webs of the steel main beams in the positive bending moment zone or the webs of the steel main beams in the negative bending moment zone.

5. The fully prestressed steel-concrete composite continuous beam bridge in the negative moment zone according to claim 4 is characterized in that: The steel-concrete composite bridge deck in the positive bending zone includes a steel bottom formwork for the bridge deck in the positive bending zone, longitudinal steel bars in the positive bending zone, transverse steel bars in the positive bending zone, and concrete in the positive bending zone; the steel bottom formwork for the bridge deck in the positive bending zone is a supporting platform for the concrete pouring construction formwork in the positive bending zone; the steel bottom formwork for the bridge deck in the positive bending zone includes an edge steel bottom plate in the positive bending zone, a middle steel bottom plate in the positive bending zone, transverse ribs of the perforated plate in the positive bending zone, bolts of the steel bottom plate in the positive bending zone, and bolt fixing holes of the steel bottom plate in the positive bending zone; two edge steel bottom plates in the positive bending zone are symmetrically arranged on both sides of the middle steel bottom plate in the positive bending zone; a plurality of transverse ribs of the perforated plate in the positive bending zone are fixed parallel to each other on the edge steel bottom plates and the positive bending zone A number of positive moment zone steel bottom plate bolts are welded on the positive moment zone side steel bottom plate and the positive moment zone middle steel bottom plate, positive moment zone steel bottom plate side steel bottom plate and the positive moment zone middle steel bottom plate are provided with positive moment zone steel bottom plate bolt fixing holes, the positive moment zone steel bottom plate bolt fixing holes correspond to the positions of the welding bolts of the positive moment zone steel main beam, a plurality of positive moment zone longitudinal steel bars are sequentially arranged on the transverse ribs of the positive moment zone perforated plate, a plurality of positive moment zone transverse steel bars are sequentially arranged on the positive moment zone longitudinal steel bars, and the steel-concrete composite section beam of the positive moment zone steel main beam and the positive moment zone steel-concrete composite bridge deck is formed by pouring positive moment zone concrete.

6. The fully prestressed steel-concrete composite continuous beam bridge in the negative moment zone according to claim 5 is characterized in that: The negative bending zone steel-concrete composite bridge deck comprises a negative bending zone bridge deck steel bottom formwork, negative bending zone longitudinal steel bars, negative bending zone transverse steel bars, negative bending zone concrete, a longitudinal prestressing system, a built-in wet joint prestressing system, a built-in wet joint, a sealing rubber tube, and a sealing rubber tube slurry; The steel bottom formwork of the bridge deck in the negative bending moment area includes the side steel bottom plate in the negative bending moment area, the middle steel bottom plate in the negative bending moment area, the channel beam, the transverse rib of the perforated plate in the negative bending moment area, the steel bottom plate bolts in the negative bending moment area, the steel bottom plate lock mouth in the negative bending moment area, and the polytetrafluoroethylene plate of the steel bottom plate in the negative bending moment area; The built-in wet joint comprises a built-in wet joint space, a built-in wet joint slurry poured in the built-in wet joint space, and a built-in wet joint prestressing system arranged in the built-in wet joint slurry; The trough beam comprises a trough plate, a trough beam stiffening rib, a trough plate top bolt, and a trough plate bottom bolt, and the trough beam stiffening rib, the trough plate top bolt, and the trough plate bottom bolt are welded to the trough plate; The trough beam stiffening ribs include trough beam stiffening rib plates, trough beam stiffening rib openings arranged on the trough beam stiffening rib plates, and trough beam stiffening rib locks arranged on the trough beam stiffening rib plates; the trough beam stiffening rib openings and the built-in wet joint slurry form a PBL shear connection key, the trough beam stiffening rib locks are connected to the corresponding positions of the negative moment zone steel main beam locks, the trough beam stiffening rib locks are arranged along the longitudinal bridge length, a sealing rubber tube is arranged in the trough beam stiffening rib locks, and a sealing rubber tube slurry is formed after grouting, so that the trough beam is closely connected to the top plate of the steel main beam in the negative moment zone, and the trough beam stiffening ribs are used to separate the built-in wet joint space to form a plurality of nearly square spaces, and a number of paths are arranged according to the width of the top plate of the steel main beam in the negative moment zone; Two negative moment zone side steel bottom plates are symmetrically arranged on both sides of the negative moment zone middle steel bottom plate. Both ends of the negative moment zone middle steel bottom plate are connected to the two negative moment zone side steel bottom plates on both sides through a trough beam. The trough beam is welded to the negative moment zone side steel bottom plates and the negative moment zone middle steel bottom plate. The top surfaces of the three are flush. Several negative moment zone perforated plate transverse ribs are arranged in parallel and welded on the top surfaces of the three to jointly form a load-bearing structure and a template for pouring concrete in the negative moment zone. A negative moment zone steel bottom plate lock is arranged at the connection between the negative moment zone middle steel bottom plate and the trough beam. A negative moment zone steel bottom plate polytetrafluoroethylene plate is arranged at the bottom of the negative moment zone steel bottom plate lock; the negative moment zone steel bottom plate bolts are welded to the negative moment zone side steel bottom plates and the negative moment zone middle steel bottom plates. A plurality of longitudinal steel bars in the negative bending moment area and a plurality of longitudinal prestressing systems are sequentially arranged on the transverse ribs of the perforated plate in the negative bending moment area, a plurality of transverse steel bars in the negative bending moment area are sequentially arranged on the longitudinal steel bars in the negative bending moment area, the locking mouth of the steel bottom plate in the negative bending moment area is connected with the locking mouth of the steel main beam in the negative bending moment area at the corresponding position, the locking mouth of the steel bottom plate in the negative bending moment area is arranged along the longitudinal length of the bridge, a sealing rubber tube is arranged in the locking mouth of the steel bottom plate in the negative bending moment area, and a sealing rubber tube slurry is formed after grouting, which connects the steel-concrete composite bridge deck in the negative bending moment area and the steel main beam in the negative bending moment area as a whole, and forms a built-in wet joint space, the polytetrafluoroethylene plate of the steel bottom plate in the negative bending moment area is a sliding block when installing the steel bottom formwork of the bridge deck in the negative bending moment area, the longitudinal prestressing system and the built-in wet joint prestressing system are respectively used to apply the prestress of the negative bending moment area concrete and the built-in wet joint slurry to form full prestressed concrete in the longitudinal direction of the negative bending moment area.

7. The fully prestressed steel-concrete composite continuous beam bridge in the negative bending zone according to claim 6 is characterized in that: The longitudinal prestressing system includes longitudinal prestressed channels, longitudinal prestressed tendons, prestressed channel slurry, prestressed tendon anchors, and prestressed channel grouting holes; the longitudinal prestressed channels are evenly arranged in the steel-concrete composite bridge deck in the negative bending moment area, and pass through the transverse ribs of the perforated plate in the negative bending moment area, the size of the openings of the transverse ribs of the perforated plate in the negative bending moment area meets the arrangement requirements of the longitudinal prestressed channels, longitudinal prestressed tendons are arranged in the longitudinal prestressed channels, the longitudinal prestressed tendons are fixed in the longitudinal prestressed channels by prestressed tendon anchors, prestressed channel slurry is poured between the longitudinal prestressed tendons and the longitudinal prestressed channels, and prestressed channel grouting holes are arranged on the prestressed tendon anchors; the longitudinal prestressed channels use metal bellows or plastic bellows, the longitudinal prestressed tendons use steel strands, the prestressed tendon anchors use clip anchors, and micro-expansive cement mortar is used for grouting.

8. The fully prestressed steel-concrete composite continuous beam bridge in the negative moment zone according to claim 7 is characterized in that: The built-in wet joint prestressing system includes a high-strength steel wire bundle, a pier head anchor cup, a tensioning screw, an anchor nut, an anchor plate, an anchor plate fixing frame, and a sealing bolt; The anchor plate includes an anchor plate end plate, an anchor plate side plate, an anchor plate tensioning screw sleeve, an anchor plate grouting hole, an anchor plate exhaust hole, an anchor plate tensioning screw hole, an anchor plate sealing ring, and a tensioning screw sealing ring; The high-strength steel wire bundle is composed of multiple high-strength steel wires. The high-strength steel wire bundle is formed into a bundle through the pier head anchor cup. The pier head anchor cup is a hollow metal cylinder with threads inside, which is used in conjunction with the tensioning screw. The tensioning screw has threads at both ends and no threads in the middle. One end of the tensioning screw is connected to the pier head anchor cup, and the other end of the tensioning screw is connected to the anchor nut. The connection length is adjusted through the threaded section of the tensioning screw, which is used for tensioning the high-strength steel wire bundle. The anchor plate and anchor plate fixing frame are used in combination. The cross-section of the opening in the anchor plate fixing frame is consistent with the cross-section size of the anchor plate end plate, so that the anchor plate can be installed in the anchor plate fixing frame. The anchor plate fixing frame is adapted to the built-in wet joint and has the same shape as the groove plate. After the tensioning of the longitudinal prestressed tendons is completed, the top surface and two side surfaces of the anchor plate fixing frame are welded to the groove plate respectively, and the bottom surface of the anchor plate fixing frame is welded to the top plate of the steel main beam in the positive bending moment zone. Anchor plate grouting holes, anchor plate exhaust holes, and anchor plate tensioning screw holes are opened on the anchor plate end plates. The anchor plate grouting holes and anchor plate exhaust holes are closed with sealing bolts. Anchor plate sealing rings are arranged at the ends of the anchor plate side plates. The anchor plate tensioning screw sleeve is a hollow cylinder. The anchor plate tensioning screw hole in the middle of the anchor plate tensioning screw sleeve has the same diameter as the tensioning screw. One end of the anchor plate tensioning screw sleeve is welded to the anchor plate end plate, and a tensioning screw sealing ring is arranged at the other end of the anchor plate tensioning screw sleeve.

9. The fully prestressed steel-concrete composite continuous beam bridge in the negative moment zone according to claim 8, characterized in that: The post-cast steel-concrete composite bridge deck comprises a post-cast steel bottom formwork for the bridge deck, post-cast longitudinal steel bars, post-cast transverse steel bars, and post-cast concrete; the post-cast steel bottom formwork for the bridge deck comprises a post-cast edge steel bottom plate, a post-cast middle steel bottom plate, a post-cast perforated plate transverse ribs, post-cast steel bottom plate bolts, and post-cast steel bottom plate bolt fixing holes; the structure of the post-cast steel-concrete composite bridge deck is the same as that of the steel-concrete composite bridge deck in the positive bending moment zone. According to construction needs, some post-cast perforated plate transverse ribs and post-cast steel bottom plate bolts are welded after the construction of the longitudinal prestressing system and the built-in wet joint prestressing system is completed.

10. A construction method for a fully prestressed steel-concrete composite continuous beam bridge in a negative bending moment area, applied to the fully prestressed steel-concrete composite continuous beam bridge in a negative bending moment area according to claim 9, characterized in that: The following steps are involved: Step 1: Install the steel main beam and steel cross beam, splice and install the steel main beam in the positive bending moment area and the steel main beam in the negative bending moment area on the bracket, and install the steel cross beam between the steel main beams, using welding or bolting to install, and remove the bracket after installation; Step 2: Install sealing rubber strips on the steel main beams in the positive bending moment area except for the post-cast steel-concrete composite bridge deck area; Step 3: Install a sealing rubber tube in the locking mouth of the steel main beam in the negative bending moment area to seal the locking mouth of the steel bottom plate in the negative bending moment area and the locking mouth of the channel beam stiffening rib; Step 4: Lay high-strength steel wire bundles with pier head anchor cups and tensioning screws on the steel main beam in the negative bending moment area; Step 5: Install the steel bottom formwork of the bridge deck in the positive bending moment area, use a crane to hoist the steel bottom formwork of the bridge deck in the positive bending moment area onto the steel main beam in the positive bending moment area, and then fix it with welding bolts of the steel main beam in the positive bending moment area; Step 6: Install the steel bottom formwork of the bridge deck in the negative bending area, install a winch on the installed steel bottom formwork of the bridge deck in the positive bending area, hoist the steel bottom formwork of the bridge deck in the negative bending area to the steel main beam in the positive bending area corresponding to the position of the post-cast steel-concrete composite bridge deck, and use the winch to drag it, combined with the friction of the polytetrafluoroethylene plate of the steel bottom plate of the negative bending area on the steel bottom formwork of the bridge deck in the negative bending area, to install each section of the steel bottom formwork of the bridge deck in the negative bending area in place in sequence. After installation, remove the winch, and then weld the contact surfaces of each section: the side steel bottom plate of the negative bending area, the middle steel bottom plate of the negative bending area, and the trough plate; Step 7: Install sealing rubber strips on the steel main beams in the positive bending moment area of ​​the post-cast steel-concrete composite bridge deck; Step 8: Install the post-casting belt bridge deck steel bottom formwork, use a crane to hoist the post-casting belt bridge deck steel bottom formwork to the steel main beam in the positive bending moment area, and then fix it through the welding bolts of the steel main beam in the positive bending moment area. The post-casting belt bridge deck steel bottom formwork is used as a working platform for tensioning the prestress of the steel-concrete composite bridge deck in the negative bending moment area. According to the tensioning construction requirements, some post-casting belt perforated plate transverse ribs and post-casting belt steel bottom plate bolts are welded after the prestressing construction is completed; Step 9: Tie the longitudinal reinforcement and transverse reinforcement in the positive bending moment area to the steel bottom formwork of the bridge deck in the positive bending moment area, pour the concrete in the positive bending moment area and maintain it; Step 10: Arrange longitudinal prestressed channels on the bottom formwork of the bridge deck steel in the negative bending moment area, tie the longitudinal steel bars in the negative bending moment area and the transverse steel bars in the negative bending moment area, pour the concrete in the negative bending moment area and maintain it; Step 11: When the concrete strength in the negative moment zone reaches more than 90%, the longitudinal prestressed tendons in the steel-concrete composite bridge deck in the negative moment zone are tensioned, anchored by prestressed tendon anchors, and the longitudinal prestressed channels are grouted through the prestressed channel grouting holes; Step 12: Grout the sealing rubber tube on the steel main beam in the negative bending moment area, so that the trough plate, the side steel bottom plate in the negative bending moment area, the middle steel bottom plate in the negative bending moment area and the top plate of the steel main beam in the negative bending moment area form a closed section. At the same time, the trough beam stiffening rib is also connected to the top plate of the steel main beam in the negative bending moment area; Step 13: Install the built-in wet joint anchor, weld the anchor plate fixing frame to the channel plate and the top plate of the steel main beam in the negative bending moment area, and form a built-in wet joint space in the steel box space; Step 14: Grout the built-in wet joint space through the anchor plate grouting holes on the anchor plate. After the grouting is completed, seal the anchor plate grouting holes and the anchor plate exhaust holes with sealing bolts; Step 15: Before the initial setting of the built-in wet joint slurry, the high-strength steel wire bundle is tensioned and anchored with anchor nuts; Step 16: Weld the post-cast strip perforated plate transverse ribs and post-cast strip steel bottom plate bolts on the post-cast strip steel-concrete composite bridge deck, tie the post-cast strip longitudinal steel bars and post-cast strip transverse steel bars, pour the post-cast strip concrete and maintain.

Images