High-effect bridging wet joint stress lattice for assembly type steel-concrete composite beam

Abstract

The invention relates to a high-effect bridging wet joint stress lattice for a fabricated steel-concrete composite beam, and belongs to the technical field of bridge structure engineering. Comprising a prefabricated concrete bridge deck, a high-performance wet joint, unbonded prestressed fishbone steel bars, embedded threaded sleeves, detachable local reinforcing limiting bolts, extrusion anchorage devices, a bridge deck reinforcement cage and corrugated constraint steel sheets. The unbonded prestressed fishbone steel bar comprises an unbonded prestressed steel bar, a resettable self-adaptive anchoring steel bar and a limiting hole. The invention aims to solve the problem that the upper bridge deck slab of the hogging moment area of the steel-concrete composite beam is easy to crack, has the advantages of multi-stage stress mode, optimization of bridge deck slab stress distribution, delay of bridge deck slab cracking, convenience in disassembly and replacement and the like, and can be applied to the fabricated steel-concrete composite beam. The material can also be used for cast-in-place steel-concrete composite beams, steel-concrete laminated slabs, steel-concrete composite columns and other positions, and a wide foundation can be provided for further application and popularization of high-performance materials in the steel-concrete composite beams.

Description

Technical Field

[0001] The invention relates to a bridge deck stress-bearing structure, in particular to a high-efficiency bridge-joint wet joint stress-bearing lattice structure for assembled steel-concrete composite beams, belonging to the technical field of bridge structure engineering. Background Art

[0002] Steel-concrete composite beams have a reasonable structural type and stress mode. They give full play to the compressive properties of concrete and the tensile properties of steel. At the same time, they control the problems of concrete tensile cracking and serious deformation of steel beams to a certain extent. Therefore, (prefabricated) steel-concrete composite beams have been widely promoted and applied in recent years. However, steel-concrete composite beams have also suffered from various forms of defects during operation, such as cracking of negative moment bridge decks, cracking of the joints between the post-cast section and the precast concrete bridge deck, and failure of shear nails between the concrete bridge deck and the steel beam. In addition, with the requirements of building industrialization, standardization and green construction, prefabricated steel-concrete composite beams have gradually emerged. As a result, the interface failure between the precast concrete bridge deck and the wet joint, the uncoordinated deformation and force transmission, and the insufficient performance of the wet joint have become more prominent.

[0003] At present, a variety of improvement measures and methods have been proposed to address the problems of cracking of bridge decks in negative bending moment areas of (assembled) steel-concrete composite beams, cracking of joints between wet joints and precast concrete bridge decks, and insufficient performance of wet joints, such as increasing the reinforcement ratio of concrete slabs, fulcrum jacking, tensioning prestressing (such as the wet joint structure and assembly method of prefabricated assembled bridge decks disclosed in CN109610314A, including prefabricated concrete bridge decks with reserved cast-in-place holes; prefabricated concrete bridge decks with reserved prestressed channels, embedded steel plates on both sides, and oblique shear nails or vertical high-strength bolts welded to the bottom of the embedded steel plates, and the prefabricated assembled bridge decks based on X-type prestressed tendon connections disclosed in CN109610312A, including prefabricated concrete bridge decks, X-type prestressed tendons, gaskets, anchors, reserved prestressed channels, waterstops, and reserved cast-in-place holes), mid-span weighting method, etc. These construction processes can improve the possibility of the above-mentioned defects in (prefabricated) steel-concrete composite beams during operation to a certain extent. In addition, with the development of engineering material technology, high-performance concrete with higher mechanical properties, good toughness and excellent crack control ability has gradually been introduced into (prefabricated) steel-concrete composite beams, such as Engineered Cementitious Composite (ECC), Ultra-High Performance Concrete (UHPC), Light-Weight Concrete, etc. The introduction of these new materials provides new ideas for the design and application of prefabricated steel-concrete composite beams. However, it should be pointed out that the application of high-performance wet joints in prefabricated steel-concrete composite beams generally has problems such as insufficient performance of high-performance wet joint materials, obvious damage failure transfer phenomenon, and no obvious improvement effect on the durability and bearing capacity of prefabricated steel-concrete composite beams. Summary of the invention

[0004] In order to solve the problems commonly existing in the existing prefabricated steel-concrete composite beam bridge deck, such as insufficient performance of high-performance wet joint materials, obvious damage failure transfer phenomenon, and no obvious effect on improving the durability and bearing capacity of the prefabricated steel-concrete composite beams, the present invention proposes a high-efficiency bridge wet joint force-bearing lattice for prefabricated steel-concrete composite beams.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is as follows: A high-performance bridge wet joint force-bearing lattice for assembled steel-concrete composite beams, comprising a precast concrete bridge deck, a high-performance wet joint, unbonded prestressed fishbone steel bars, embedded threaded sleeves, removable local reinforcement limit bolts, extrusion anchors, a bridge deck steel cage and corrugated restraining steel sheets; The bridge deck reinforcement cage is arranged in the precast concrete bridge deck, and a plurality of the unbonded prestressed fishbone reinforcements are arranged in the middle area of ​​the reinforcement cage of the bridge deck at intervals along the transverse direction and the longitudinal direction of the bridge; The unbonded prestressed fishbone steel bar comprises an unbonded prestressed steel bar, a resettable adaptive anchoring steel bar and a limiting hole; the extruded anchor anchors the unbonded prestressed steel bar in the precast concrete bridge deck, and at the same time, both ends of the longitudinal unbonded prestressed steel bar extend into the high-performance wet joint; The unbonded prestressed steel bars are welded with resettable adaptive anchoring steel bars of different lengths and diameters at different intervals, thereby forming unbonded prestressed fishbone steel bars; at the same time, limited holes are arranged at the intersections of the longitudinal and transverse unbonded prestressed steel bars, so that the embedded threaded sleeves are passed through the entire plate through the limited holes and embedded in the precast concrete bridge deck, and the removable local reinforcement limit bolts are fixed in the embedded threaded sleeves by screwing; The longitudinal unbonded prestressed fishbone steel bars extending from adjacent precast concrete bridge decks are staggered and overlapped in high-performance wet joints, and the staggered unbonded prestressed fishbone steel bars are connected through the corrugated restraining steel sheets.

[0006] Furthermore, the precast concrete bridge deck and the high-performance wet joint constitute an upper concrete structure; when the upper concrete structure is in an elastic state, the tensile stress generated by the negative bending moment in the precast concrete bridge deck and the high-performance wet joint is firstly rapidly transmitted between the high-performance wet joints along the longitudinal unbonded prestressed steel bars, and the longitudinal unbonded prestressed steel bars in the precast concrete bridge deck bear this part of the tensile stress by offsetting the compressive stress pre-applied on the upper part, so that the upper concrete structure is still in a compressive state, avoiding structural cracking; When the upper concrete structure enters the limit state of normal use, as the tensile stress further increases, the longitudinal unbonded prestressed fishbone steel bars will produce a certain degree of displacement after being stressed, thereby driving the resettable adaptive anchor steel bars welded on the upper part thereof, so that the resettable adaptive anchor steel bars and the precast concrete bridge deck produce relative displacement. Under the shearing action, the stress on the longitudinal unbonded prestressed steel bars is transferred to the precast concrete bridge deck in steps and positions, and the main tensile stress is transferred to the high-performance wet joints at the same time. The effective transfer of tensile stress in the high-performance wet joints is ensured by the corrugated constraint steel sheet; When the upper concrete structure enters the ultimate bearing capacity state, the longitudinal unbonded prestressed fishbone steel bars undergo large displacement under the action of tensile stress, causing the removable local reinforcement limit bolts in the limit holes to come into contact with the unbonded prestressed fishbone steel bars, so that the stress they bear is transmitted to the precast concrete bridge deck through the removable local reinforcement limit bolts, so as to achieve the coordinated work of the unbonded prestressed fishbone steel bars and the precast concrete bridge deck and its internal bridge deck steel cage, and finally realize the multi-stage force-bearing lattice of prestressed steel rods-wet joints-bridge decks.

[0007] Furthermore, the length L of the limiting hole is greater than the shear yield displacement of the resettable adaptive anchor steel bar. twice as much.

[0008] Furthermore, by adjusting the diameter d and spacing l of the repositionable adaptive anchoring steel bar, it can be applied to composite beam bridge decks of different sizes or forms, wherein the diameter d of the repositionable adaptive anchoring steel bar directly affects its shear stress. The diameter d of the repositionable adaptive anchor steel bar should ensure the shear yield stress of the repositionable adaptive anchor steel bar. Less than the concrete compressive bearing capacity of precast concrete bridge decks , so that the yield failure of the resettable adaptive anchor steel bar precedes the cracking of the concrete, and at the same time, the resettable adaptive anchor steel bar will not reach its shear yield displacement under normal use of the structure. , so that when the load is reduced, the resettable adaptive anchoring steel bars can return to their initial state; the spacing l of the resettable adaptive anchoring steel bars will directly affect the number of resettable adaptive anchoring steel bars, and then affect the stress level of the longitudinal unbonded prestressed steel bars distributed to the precast concrete bridge deck; for prefabricated steel-concrete composite beam precast concrete bridge decks of different sizes or load states, the diameter and spacing of the resettable adaptive anchoring steel bars can be calculated and changed to ensure that they can fully exert their performance under normal use of the structure.

[0009] Furthermore, the resettable adaptive anchoring steel bar is a shape memory alloy.

[0010] Furthermore, the removable local reinforcement limit bolt is installed in the precast concrete bridge deck through an embedded threaded sleeve, which is convenient for rapid disassembly and replacement when failure occurs. At the same time, the middle area of ​​the removable local reinforcement limit bolt is wrapped with a layer of CFRP mesh cloth to achieve a local reinforcement effect to resist the shearing effect on the middle part of the removable local reinforcement limit bolt when the longitudinal and transverse unbonded prestressed fishbone steel bars are displaced.

[0011] Furthermore, the limit holes penetrate the longitudinal and transverse unbonded prestressed fishbone steel bars; when the unbonded prestressed fishbone steel bars are displaced to a certain extent, the detachable local reinforcement limit bolts will come into contact with the unbonded prestressed fishbone steel bars, so that the stress it bears is transmitted to the precast concrete bridge deck through the detachable local reinforcement limit bolts, ultimately achieving overall coordinated force on the upper concrete structure.

[0012] Furthermore, the stress mode of a single corrugated zone in the corrugated restrained steel sheet is the same as the stress mode of the arch structure. When the unbonded prestressed fishbone steel bars constrained in a single corrugated zone are displaced due to stress, pressure is exerted on the corrugated zone, thereby better exerting the compressive properties of concrete, thereby preventing the corrugated restrained steel sheet from being pulled out of the high-performance wet joint. At the same time, the corrugated restrained steel sheet can exert mutual constraints on adjacent unbonded prestressed fishbone steel bars; when the unbonded prestressed fishbone steel bars exert pressure on the corrugated restrained steel sheet, the corrugated restrained steel sheet can also constrain the displacement of the unbonded prestressed fishbone steel bars, ensuring that it can return to its initial state after a small displacement, so that it has a certain self-resetting ability.

[0013] Furthermore, the extrusion anchor is extruded and arranged at the outer edge of the precast concrete bridge deck; the extrusion anchor comprises an extrusion plate, an extrusion bolt on the outer side and an extrusion spring on the inner side; and a plurality of resettable adaptive anchor steel bars are exposed on the unbonded prestressed fishbone steel bars at the outer end of the extrusion anchor.

[0014] Furthermore, the upper and lower ends of the hollow inner diameter of the embedded threaded sleeve are provided with internal threads, the upper and lower ends of the outer surface of the removable local reinforcement limit bolt are provided with external threads, and a nut is provided on the top of the removable local reinforcement limit bolt.

[0015] After adopting the above technical solution, the present invention has the following beneficial effects compared with the prior art: 1) The present invention can optimize the stress distribution in the bridge deck in the negative bending moment area of ​​the composite beam and delay the cracking of the bridge deck; 2) The present invention establishes a prestressed steel rod-high-performance wet joint-precast concrete bridge deck load-bearing lattice structure to achieve multi-stage load-bearing of the combined structure; 3) The limiting components are fixed in the prefabricated parts by bolts, which is convenient for disassembly and replacement at any time during the subsequent operation and maintenance of the structure, thus extending the service life of the new lattice structure; 4) The present invention can be used in assembled steel-concrete composite beams, cast-in-place steel-concrete composite beams, and can also be used in steel-concrete composite slabs, steel-concrete composite columns, etc.; 5) The present invention has the advantages of being economical and convenient, prefabricated in factories, having a reasonable force transmission mechanism, optimizing the stress distribution of bridge decks, and being replaceable. It can provide a basis for the further promotion and application of high-performance materials in cast-in-place and assembled steel-concrete composite beam bridge decks, and has broad theoretical research significance and practical value. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A three-dimensional schematic diagram of a high-efficiency bridge wet joint force-bearing lattice for an assembled steel-concrete composite beam of the present invention; Figure 2 A three-dimensional schematic diagram of ordinary steel bars and steel bar lattice structure of the bridge deck of the present invention; Figure 3 A three-dimensional schematic diagram of the unbonded prestressed fishbone reinforcement of the present invention; Figure 4 This is a schematic diagram of the installation of the detachable local reinforcement limit bolt of the present invention; Figure 5 Detailed schematic diagram of the combination of the embedded threaded sleeve and the removable local reinforcement limit bolt, wherein (a) is a schematic diagram of the removable local reinforcement limit bolt; (b) is a cross-sectional view of the embedded threaded sleeve; (c) is a schematic diagram of the combination of the embedded threaded sleeve and the removable local reinforcement limit bolt; Figure 6 It is a side view of the transverse bridge direction of the high-efficiency bridge-jointed wet joint force-bearing lattice structure for the assembled steel-concrete composite beam of the present invention; Figure 7 It is a longitudinal side view of the high-efficiency bridge wet joint force-bearing lattice structure for the assembled steel-concrete composite beam of the present invention; Figure 8 A top view of a high-efficiency bridging wet joint force-bearing lattice structure for an assembled steel-concrete composite beam of the present invention; Fig. 9 It is a top view of the steel bar lattice structure at the wet joint; Fig.10 Schematic diagram of the details of the corrugated restraint steel sheet. DETAILED DESCRIPTION

[0017] The following is combined with Figure 1-10 The present invention is further described in detail with specific implementations to facilitate a clear understanding of the present invention, but they do not constitute a limitation on the present invention.

[0018] In the description of the present invention, it should be noted that the directions or positional relationships indicated by terms such as “upper”, “lower”, “front”, “back”, “left”, “right”, “vertical”, “inside” and “outside” are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0019] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0020] As attached Figure 1-10 As shown, a high-performance bridge wet joint force-bearing lattice for an assembled steel-concrete composite beam of this embodiment includes a precast concrete bridge deck 1, a high-performance wet joint 2, unbonded prestressed fishbone steel bars 3, embedded threaded sleeves 4, removable local reinforcement limit bolts 5, extrusion anchors 6, bridge deck steel cages 7, and corrugated restraining steel sheets 8. A bridge deck steel cage 7 is arranged in the precast concrete bridge deck 1, and a plurality of unbonded prestressed fishbone steel bars 3 are arranged in the middle area of ​​the steel bars of the bridge deck steel cage 7 along the transverse and longitudinal directions of the bridge.

[0021] like Figure 2-4 The unbonded prestressed fishbone reinforcement 3 includes an unbonded prestressed steel bar 3-1, a resettable adaptive anchoring reinforcement 3-2, and a limiting hole 3-3. In this embodiment, the resettable adaptive anchoring reinforcement 3-2 is a shape memory alloy. The extruded anchor 6 anchors the unbonded prestressed steel bar 3-1 in the precast concrete bridge deck 1, and at the same time, both ends of the longitudinal unbonded prestressed steel bar 3-1 extend into the high-performance wet joint 2.

[0022] In this embodiment, the extrusion anchor 6 is extruded and arranged on the outer edge of the precast concrete bridge deck 1. The extrusion anchor 6 includes an extrusion plate, an extrusion bolt on the outer side, and an extrusion spring on the inner side. A plurality of resettable adaptive anchor steel bars 3-2 are exposed on the unbonded prestressed fishbone steel bars 3 at the outer end of the extrusion anchor 6.

[0023] In addition, if Figure 9-10 As shown, the stress mode of a single corrugated grid in the corrugated restrained steel sheet 8 is the same as the stress mode of the arch structure. When the unbonded prestressed fishbone steel bar 3 constrained in a single corrugated grid is displaced due to the force, pressure will be applied to the corrugated grid, thereby better exerting the compressive properties of the concrete, thereby preventing the corrugated restrained steel sheet 8 from being pulled out of the high-performance wet joint 2. At the same time, the corrugated restrained steel sheet 8 can impose mutual constraints on the adjacent unbonded prestressed fishbone steel bars 3. When the unbonded prestressed fishbone steel bar 3 exerts pressure on the corrugated restrained steel sheet 8, the corrugated restrained steel sheet 8 can also constrain the displacement of the unbonded prestressed fishbone steel bar 3, ensuring that it can also return to its initial state after a small displacement, so that it has a certain self-reset ability.

[0024] Resettable adaptive anchoring steel bars 3-2 of different lengths and diameters are welded to the unbonded prestressed steel bars 3-1 at different intervals, thereby forming unbonded prestressed fishbone steel bars 3. At the same time, limit holes 3-3 are set at the intersections of the longitudinal and transverse unbonded prestressed steel bars 3-1, so that the embedded threaded sleeve 4 passes through the limit holes 3-3 and is embedded in the precast concrete bridge deck 1, and the removable local reinforcement limit bolts 5 are fixed in the embedded threaded sleeve 4 by screwing. The longitudinal unbonded prestressed fishbone steel bars 3 extending from adjacent precast concrete bridge decks 1 are staggered and overlapped in the high-performance wet joints 2, and the staggered unbonded prestressed fishbone steel bars 3 are connected through the corrugated constraint steel sheets 8. The limit holes 3-3 penetrate the longitudinal and transverse unbonded prestressed fishbone steel bars 3. When the unbonded prestressed fishbone steel bars 3 undergo a certain displacement, the removable local reinforcement limit bolts 5 will come into contact with the unbonded prestressed fishbone steel bars 3, so that the stress borne by them is transmitted to the precast concrete bridge deck 1 through the removable local reinforcement limit bolts 5, ultimately achieving overall coordinated force on the upper concrete structure.

[0025] The length L of the limit hole 3-3 is greater than the shear yield displacement of the resettable adaptive anchor steel bar 3-2. By adjusting the diameter d and spacing l of the resettable adaptive anchoring steel bar 3-2, it can be applied to composite beam bridge decks of different sizes or forms, wherein the diameter d of the resettable adaptive anchoring steel bar 3-2 directly affects its shear stress. The diameter d of the repositionable adaptive anchoring steel bar 3-2 should ensure the shear yield stress of the repositionable adaptive anchoring steel bar 3-2. Less than the concrete compressive bearing capacity of the precast concrete bridge deck 1 , so that the yield failure of the resettable adaptive anchoring steel bar 3-2 precedes the cracking of the concrete, and at the same time, the resettable adaptive anchoring steel bar 3-2 will not reach its shear yield displacement under normal use of the structure. , so that when the load is reduced, the resettable adaptive anchoring steel bar 3-2 can return to its initial state. The spacing l of the resettable adaptive anchoring steel bar 3-2 will directly affect the number of the resettable adaptive anchoring steel bars 3-2, and thus affect the stress level of the longitudinal unbonded prestressed steel bars 3-1 distributed to the precast concrete bridge deck 1. For prefabricated steel-concrete composite beam precast concrete bridge decks 1 of different sizes or load states, the diameter and spacing of the resettable adaptive anchoring steel bars 3-2 can be calculated and changed to ensure that they can fully exert their performance under normal use of the structure.

[0026] like Figure 3-5As shown, the removable local reinforcement limit bolt 5 is installed in the precast concrete bridge deck 1 through the embedded threaded sleeve 4, which is convenient for rapid removal and replacement when it fails. At the same time, the middle area of ​​the removable local reinforcement limit bolt 5 is wrapped with a layer of CFRP mesh cloth to achieve the effect of local reinforcement to resist the shearing effect on the middle part of the removable local reinforcement limit bolt 5 when the longitudinal and transverse unbonded prestressed fishbone steel bars 3 are displaced. The upper and lower ends of the hollow inner diameter of the embedded threaded sleeve 4 are provided with internal threads, the upper and lower ends of the outer surface of the removable local reinforcement limit bolt 5 are provided with external threads, and the top of the removable local reinforcement limit bolt 5 is provided with a nut.

[0027] Specifically, in this embodiment, Figure 1 , Figure 2 As shown, two precast concrete bridge decks 1 with a size of 7800*2200*280mm are fixed at intervals. The precast concrete bridge deck 1 is ordinary concrete of C55 grade. An ECC high-performance wet joint 2 with a width of 300mm is poured in the middle. φ16@280mm steel bars are arranged along the longitudinal direction of the bridge in the precast concrete bridge deck 1, and φ18@493 / 986mm steel bars are arranged along the transverse direction of the bridge. The steel bars are fixed to form a bridge deck steel cage 7 by steel wire binding stirrups. In the middle of the bridge deck steel cage 7, φ16@280mm steel bars are arranged along the transverse direction of the bridge at an interval of 700mm. Three transverse unbonded prestressed fishbone steel bars 3 are evenly arranged, and seven longitudinal unbonded prestressed fishbone steel bars 3 are evenly arranged at a spacing of 1100mm along the transverse direction of the bridge. Removable local reinforcement limit bolts 5 are installed in the limit holes 3-3 at the intersections of the longitudinal and transverse unbonded prestressed fishbone steel bars. Both ends of the unbonded prestressed fishbone steel bars 3 extend into the ECC high-performance wet joints 2 with a length of 250mm, and a corrugated restraint steel sheet 8 with a size of 8-70-550-7300mm is arranged at the tail of the staggered unbonded prestressed fishbone steel bars.

[0028] like Figure 3 As shown, the unbonded prestressed fishbone steel bar 3 includes an unbonded prestressed steel bar 3-1 with a diameter of 25 mm, the length of the longitudinal unbonded prestressed fishbone steel bar 3 is 2700 mm, and the length of the transverse unbonded prestressed fishbone steel bar 3 is 8300 mm, the side welded repositionable adaptive anchoring steel bar 3-2 has a diameter of 6 mm, a length between 150-500 mm, a welding spacing between 200-550 mm, and a limit hole 3-3 with a length of 33 mm is cut on the unbonded prestressed steel bar 3-1. The middle body of the unbonded prestressed fishbone steel bar 3 is placed in the precast concrete bridge deck 1, and the longitudinal unbonded prestressed fishbone steel bar 3 is anchored by using extrusion anchors 6 at both ends of the precast concrete bridge deck 1 to achieve the unbonded prestressed construction effect, and the laterally extended repositionable adaptive anchoring steel bar 3-2 is directly cast in the precast concrete bridge deck 1.

[0029] like Figure 4 , Figure 5 As shown, the diameter of the removable local reinforcement limit bolt 5 is 13mm, the length is 280mm, the thread length at both ends is 80mm, the middle part is thinned by 8mm, and wrapped with a 5mm thick CFRP mesh cloth, with a 10mm thick nut on the top and a diameter of 20mm. The outer diameter of the embedded threaded sleeve 4 in the precast concrete bridge deck 1 is 17mm, the inner diameter is 14mm, the length is 280mm, and 80mm threads are also set at both ends. The middle part is a smooth sleeve. In actual application, the embedded threaded sleeve is passed through the limit hole 3-3 and cast in the precast concrete bridge deck, and then the removable local reinforcement limit bolt 5 is fixed in the embedded threaded sleeve 4 by screwing. When the removable local reinforcement limit bolt 5 needs to be replaced later, it can also be quickly replaced by screwing.

[0030] like Fig. 9 , Fig.10 As shown, both ends of the longitudinal unbonded prestressed fishbone steel bars 3 extend into the ECC high-performance wet joint 2 with a length of 250 mm. The repositionable adaptive anchor steel bars 3-2 welded on the upper part have a diameter of 8 mm, a length of 200 mm, and a spacing of 150 mm. A corrugated restraint steel sheet 8 with a size of 8-70-550-7300 mm is arranged at the tail of the unbonded prestressed fishbone steel bars 3 staggered in the wet joint 2, and circular holes with a diameter of 25 mm are pre-cut on the corrugated restraint steel sheet 8 with a spacing of 550 mm, which is convenient for welding at the tail of the unbonded prestressed fishbone steel bars 3 during construction to ensure the continuity of the steel bar force grid.

[0031] like Figure 6-8 It is a three-dimensional schematic diagram, side view, top view and front view of the load-bearing lattice of this embodiment, which can more fully demonstrate the specific detailed settings of this invention patent.

[0032] In this embodiment, the principle of the present invention is: The precast concrete bridge deck 1 and the high-performance wet joint 2 constitute the upper concrete structure. When the upper concrete structure is in an elastic state, the tensile stress generated by the negative bending moment in the precast concrete bridge deck 1 and the high-performance wet joint 2 is firstly rapidly transmitted along the longitudinal unbonded prestressed steel rods 3-1 between the high-performance wet joints 2, while the longitudinal unbonded prestressed steel rods 3-1 in the precast concrete bridge deck 1 bear this part of the tensile stress by offsetting the compressive stress pre-applied on the upper part, so that the upper concrete structure is still in a compressive state, avoiding structural cracking.

[0033] When the upper concrete structure enters the limit state of normal use, as the tensile stress further increases, the longitudinal unbonded prestressed fishbone steel bars 3 will produce a certain degree of displacement after being subjected to force, thereby driving the resettable adaptive anchor steel bars 3-2 welded on the upper part thereof, so that a relative displacement is generated between the resettable adaptive anchor steel bars 3-2 and the precast concrete bridge deck 1. Under the shear action, the stress on the longitudinal unbonded prestressed steel rods 3-1 is transferred to the precast concrete bridge deck 1 in steps and positions, and the main tensile stress is transferred to the high-performance wet joint 2 at the same time, and the effective transfer of tensile stress in the high-performance wet joint 2 is ensured by the corrugated constraint steel sheet 8.

[0034] When the upper concrete structure enters the ultimate bearing capacity state, the longitudinal unbonded prestressed fishbone steel bars 3 undergo a large displacement under the action of tensile stress, causing the removable local reinforcement limit bolts 5 in the limit holes 3-3 to come into contact with the unbonded prestressed fishbone steel bars 3, so that the stress they bear is transmitted to the precast concrete bridge deck 1 through the removable local reinforcement limit bolts 5, so as to achieve the coordinated work of the unbonded prestressed fishbone steel bars 3 and the precast concrete bridge deck 1 and the bridge deck steel cage 7 inside it, and finally realize the multi-stage force-bearing lattice of prestressed steel bars-wet joints-bridge decks.

[0035] The above is only a preferred embodiment of the present invention, and does not impose any formal limitation on the structure of the present invention. The layout type and the number of uses of the present invention are not limited to this example, and can be optimized and selected according to the actual project. Any modification, equivalent change and decoration of the above embodiment based on the technical principle of the present invention that does not deviate from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A high-efficiency bridging wet joint force-bearing lattice for assembled steel-concrete composite beams, characterized in that: It comprises a precast concrete bridge deck (1), a high-performance wet joint (2), non-bonded prestressed fishbone steel bars (3), a pre-embedded threaded sleeve (4), a removable local reinforcement limit bolt (5), an extruded anchor (6), a bridge deck steel cage (7), and a corrugated restraining steel sheet (8); The bridge deck reinforcement cage (7) is arranged in the precast concrete bridge deck (1), and a plurality of the unbonded prestressed fishbone reinforcements (3) are arranged at intervals in the middle area of ​​the reinforcements of the bridge deck reinforcement cage (7) along the transverse bridge direction and the longitudinal bridge direction; The unbonded prestressed fishbone steel bar (3) comprises an unbonded prestressed steel bar (3-1), a resettable adaptive anchoring steel bar (3-2) and a limiting hole (3-3); the extrusion anchor (6) anchors the unbonded prestressed steel bar (3-1) in the precast concrete bridge deck (1), and at the same time, both ends of the longitudinal unbonded prestressed steel bar (3-1) extend into the high-performance wet joint (2); The unbonded prestressed steel bars (3-1) are welded with resettable adaptive anchoring steel bars (3-2) of different lengths and diameters at different intervals, thereby forming unbonded prestressed fishbone steel bars (3); at the same time, limit holes (3-3) are arranged at the intersections of the longitudinal and transverse unbonded prestressed steel bars (3-1), so that the embedded threaded sleeves (4) pass through the limit holes (3-3) through the entire plate and are embedded in the precast concrete bridge deck (1); the detachable local reinforcement limit bolts (5) are fixed in the embedded threaded sleeves (4) by screwing; The longitudinal unbonded prestressed fishbone steel bars (3) extending from adjacent precast concrete bridge decks (1) are staggered and overlapped in the high-performance wet joints (2), and the staggered unbonded prestressed fishbone steel bars (3) are connected through the corrugated restraining steel sheets (8).

2. A high-efficiency bridging wet joint force-bearing lattice for assembled steel-concrete composite beams according to claim 1, characterized in that: The precast concrete bridge deck (1) and the high-performance wet joint (2) constitute an upper concrete structure; when the upper concrete structure is in an elastic state, the tensile stress generated by the negative bending moment between the precast concrete bridge deck (1) and the high-performance wet joint (2) is firstly rapidly transmitted along the longitudinal unbonded prestressed steel rods (3-1) between the high-performance wet joints (2), while the longitudinal unbonded prestressed steel rods (3-1) in the precast concrete bridge deck (1) bear the tensile stress by offsetting the compressive stress pre-applied on the upper part thereof, so that the upper concrete structure is still in a compressive state, thereby avoiding structural cracking; When the upper concrete structure enters the normal service limit state, as the tensile stress further increases, the longitudinal unbonded prestressed fishbone steel bars (3) will produce a certain degree of displacement after being subjected to the force, thereby driving the resettable adaptive anchor steel bars (3-2) welded on the upper part thereof, so that the resettable adaptive anchor steel bars (3-2) and the precast concrete bridge deck (1) produce relative displacement. Under the shearing action, the stress on the longitudinal unbonded prestressed steel bars (3-1) is transferred to the precast concrete bridge deck (1) in steps and positions, and the main tensile stress is transferred to the high-performance wet joint (2). The effective transfer of the tensile stress in the high-performance wet joint (2) is ensured by the corrugated restraining steel sheet (8); When the upper concrete structure enters the ultimate bearing capacity state, the longitudinal unbonded prestressed fishbone steel bars (3) undergo large displacement under the action of tensile stress, causing the detachable local reinforcement limit bolts (5) in the limit holes (3-3) to come into contact with the unbonded prestressed fishbone steel bars (3), so that the stress borne by the unbonded fishbone steel bars (3) is transmitted to the precast concrete bridge deck (1) through the detachable local reinforcement limit bolts (5), so that the unbonded prestressed fishbone steel bars (3) and the precast concrete bridge deck (1) and the bridge deck reinforcement cage (7) therein can work in coordination, and finally a multi-stage force-bearing lattice of prestressed steel bars-wet joints-bridge deck is realized.

3. The high-efficiency bridging wet joint force-bearing lattice for assembled steel-concrete composite beams according to claim 1, characterized in that: The length L of the limiting hole (3-3) is greater than the shear yield displacement of the resettable adaptive anchoring steel bar (3-2). twice as much.

4. The high-efficiency bridging wet joint force-bearing lattice for assembled steel-concrete composite beams according to claim 1, characterized in that: By adjusting the diameter d and the spacing l of the resettable adaptive anchoring steel bar (3-2), it can be applied to composite beam bridge decks of different sizes or forms, wherein the diameter d of the resettable adaptive anchoring steel bar (3-2) directly affects its shear stress. The diameter d of the repositionable adaptive anchor steel bar (3-2) should ensure the shear yield stress of the repositionable adaptive anchor steel bar (3-2) Less than the concrete compressive bearing capacity of the precast concrete bridge deck (1) , so that the yield failure of the resettable adaptive anchor steel bar (3-2) precedes the cracking of the concrete, and at the same time, the resettable adaptive anchor steel bar (3-2) will not reach its shear yield displacement under normal use of the structure. , so that when the load is reduced, the resettable adaptive anchoring steel bars (3-2) can return to their initial state; the spacing l of the resettable adaptive anchoring steel bars (3-2) will directly affect the number of the resettable adaptive anchoring steel bars (3-2), thereby affecting the stress level of the longitudinal unbonded prestressed steel bars (3-1) distributed to the precast concrete bridge deck (1); for prefabricated steel-concrete composite beam precast concrete bridge decks (1) of different sizes or load states, the diameter and spacing of the resettable adaptive anchoring steel bars (3-2) can be calculated and changed to ensure that they can fully exert their performance under normal use of the structure.

5. The high-efficiency bridging wet joint force-bearing lattice for assembled steel-concrete composite beams according to claim 1, characterized in that: The repositionable adaptive anchoring steel bar (3-2) is a shape memory alloy.

6. The high-efficiency bridging wet joint force-bearing lattice for assembled steel-concrete composite beams according to claim 2, characterized in that: The removable local reinforcement limit bolt (5) is installed in the precast concrete bridge deck (1) via a pre-embedded threaded sleeve (4), so as to facilitate rapid removal and replacement in the event of failure. At the same time, a layer of CFRP mesh cloth is wrapped around the middle area of ​​the removable local reinforcement limit bolt (5) to achieve a local reinforcement effect, so as to resist the shearing effect on the middle part of the removable local reinforcement limit bolt (5) when the longitudinal and transverse unbonded prestressed fishbone steel bars (3) are displaced.

7. A high-efficiency bridging wet joint force-bearing lattice for assembled steel-concrete composite beams according to claim 6, characterized in that: The limiting holes (3-3) penetrate the longitudinal and transverse unbonded prestressed fishbone steel bars (3); when the unbonded prestressed fishbone steel bars (3) are displaced to a certain extent, the detachable local reinforcement limiting bolts (5) come into contact with the unbonded prestressed fishbone steel bars (3), so that the stress borne by the unbonded fishbone steel bars is transmitted to the precast concrete bridge deck (1) through the detachable local reinforcement limiting bolts (5), and finally the overall coordinated force of the upper concrete structure is achieved.

8. The high-efficiency bridging wet joint force-bearing lattice for assembled steel-concrete composite beams according to claim 7, characterized in that: The stress mode of a single corrugated grid in the corrugated restraining steel sheet (8) is the same as the stress mode of the arch structure. When the unbonded prestressed fishbone steel bar (3) restrained in the single corrugated grid is displaced due to the stress, pressure is applied to the corrugated grid, thereby making better use of the compressive properties of the concrete, thereby preventing the corrugated restraining steel sheet (8) from being pulled out of the high-performance wet joint (2). At the same time, the corrugated restraining steel sheet (8) can impose mutual constraints on adjacent unbonded prestressed fishbone steel bars (3); when the unbonded prestressed fishbone steel bars (3) exert pressure on the corrugated restraining steel sheet (8), the corrugated restraining steel sheet (8) can also restrain the displacement of the unbonded prestressed fishbone steel bar (3), ensuring that it can return to its initial state after a small displacement, so that it has a certain self-reset capability.

9. The high-efficiency bridging wet joint force-bearing lattice for assembled steel-concrete composite beams according to claim 1, characterized in that: The extrusion anchor (6) is extruded and arranged on the outer edge of the precast concrete bridge deck (1); the extrusion anchor (6) comprises an extrusion plate, an extrusion bolt on the outer side and an extrusion spring on the inner side; and a plurality of resettable adaptive anchor steel bars (3-2) are exposed on the unbonded prestressed fishbone steel bars (3) at the outer end of the extrusion anchor (6).

10. The high-efficiency bridging wet joint force-bearing lattice for assembled steel-concrete composite beams according to claim 1, characterized in that: The upper and lower ends of the hollow inner diameter of the embedded threaded sleeve (4) are provided with internal threads, the upper and lower ends of the outer surface of the detachable local reinforcement limit bolt (5) are provided with external threads, and a nut is provided on the top of the detachable local reinforcement limit bolt (5).

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