Segmental beam-truss combined bridge adopting longitudinal limited locking connecting keys

Abstract

The invention discloses a segmental beam-truss combined bridge adopting longitudinal limited locking connecting keys, which comprises a concrete beam, the concrete beam is formed by splicing a plurality of segmental short beams along the bridge direction, and the concrete beam is arranged above a steel truss beam and is used for directly bearing the load of a bridge floor; a multidirectional locking connecting key for connecting the section short beam and the steel truss beam is arranged between the section short beam and the steel truss beam, the upper end of the multidirectional locking connecting key is fixed with an embedded part in the section short beam, and the lower end of the multidirectional locking connecting key is connected with a top plate in the steel truss beam. Additional stress caused by shrinkage creep accumulation of the bridge deck slab and long-section steel-concrete temperature difference can be effectively released, continuity of longitudinal force transfer of the concrete beam can be achieved, concrete does not need to be poured on site, the section short beam prestress efficiency is high, the later-period shrinkage creep effect of the structure can be greatly reduced, the external load force transfer path is shorter and more direct, stress is clearer, and the construction period is shortened. And a larger space is provided for optimizing the section form and size of the chord member.

Description

Technical Field

[0001] The present invention belongs to the technical field of composite bridges, and in particular relates to a segmental beam-truss composite bridge using longitudinal limited locking connecting keys. Background Art

[0002] Long-span steel-concrete composite bridges fully utilize the properties of concrete and steel, offering advantages such as outstanding economic efficiency, high overall structural rigidity, favorable conditions for high-speed traffic and ballastless track installation, and high energy efficiency. However, composite bridges generally suffer from the following drawbacks: complex design and construction of the steel-concrete combination, high construction precision requirements, temperature fluctuations that impose additional stress on the structure, the need for secondary concrete pouring to connect shear keys to the bridge deck, resulting in construction complications, the risk of cracking in the concrete slab, and low prestressing efficiency due to the combined loads of the slab and truss when prestressing the bridge deck. Summary of the Invention

[0003] The present invention is proposed to solve the problems existing in the prior art, and its purpose is to provide a segmental beam-truss combination bridge using longitudinal limited locking connecting keys.

[0004] The technical solution of the present invention is: a segmental beam-truss composite bridge using a longitudinal limited locking connecting key, including a concrete beam, which is assembled from a number of segmental short beams along the bridge direction, and the concrete beam is arranged above the steel truss beam to directly bear the bridge deck load; a multi-directional locking connecting key connecting the segmental short beam and the steel truss beam is provided between the two, the upper end of the multi-directional locking connecting key is fixed to the embedded part in the segmental short beam, and the lower end of the multi-directional locking connecting key is connected to the top plate in the steel truss beam.

[0005] Furthermore, the cross-section of the segmental short beam is a π-shaped cross-section or a box-shaped cross-section, a convex beam end tenon is formed on one side of the segmental short beam, and a concave beam end tenon is formed on the other side of the segmental short beam, and the beam end tenons and beam end tenons between adjacent segmental short beams are overlapped.

[0006] Furthermore, expansion joints are provided between the segmented short beams, and the segmented short beams are prestressed concrete beams.

[0007] Furthermore, the steel truss includes an upper chord node and an upper cross beam, and the multi-directional locking connection key includes a fixed connection key and a longitudinal limited locking connection key, the fixed connection key connects the upper chord node and the segment short beam, and the longitudinal limited locking connection key connects the upper cross beam and the segment short beam.

[0008] Furthermore, the fixed connection key includes an upper pad, a lower pad and a fixed supporting steel plate vertically connecting the two. The upper pad is fixed to the fixed connection key concrete beam embedded part in the segment short beam, and the lower pad is fixed to the top plate of the upper chord node.

[0009] Furthermore, the longitudinal limited locking connection key includes an upper sliding support plate connected to the segment short beam and a lower support groove connected to the upper crossbeam top plate. The upper sliding support plate is inserted into the lower support groove, and the two are in contact through the sliding surface between the upper and lower plates.

[0010] Furthermore, a longitudinal elastic device is provided between the upper sliding support plate and the lower support channel.

[0011] Furthermore, the upper end of the upper sliding support plate is fixed to the longitudinal limited locking connection key concrete beam embedded part in the segment short beam.

[0012] Furthermore, the lower supporting channel is fixed to the steel truss upper crossbeam top plate connecting piece at the upper end of the upper crossbeam top plate.

[0013] Furthermore, the steel truss is a truss of equal height or variable height, and the truss of the steel truss adopts a large-span steel truss, and a local stiffening structure is provided in the upper chord node of the steel truss to meet the local pressure-bearing requirements.

[0014] The beneficial effects of the present invention are as follows: The present invention divides the full-length bridge deck into several segments of equal-span short beams, and sets expansion joints between the segment short beams, which can effectively release the additional stress caused by the accumulation of shrinkage creep of the bridge deck and the temperature difference of steel and concrete in long sections.

[0015] The segmental short beams of the present invention are prefabricated in a factory and hoisted on site, avoiding on-site concrete pouring. Shear nails for connecting with the bridge deck do not need to be set above the steel trusses. At the same time, the construction is simple, the process is mature, and the quality is easier to ensure.

[0016] The segmental short beam of the present invention has a convex tenon at one end and a concave tenon at the other end. Adjacent segmental beams are overlapped by matching the convex tenon and the concave tenon, which can not only release part of the displacement of the beam end, but also realize the continuity of the longitudinal force transmission of the concrete beam.

[0017] The segmental short beams of the present invention use prestressed concrete components and are tensioned in the prefabrication site. The prestress can be fully converted into prestress of the concrete beam. The prestressing efficiency is high, ensuring that the concrete beam has sufficient crack resistance. At the same time, the storage time of the prefabricated components in the factory can be appropriately extended, which can greatly reduce the shrinkage and creep effects of the structure in the later stage.

[0018] The external load borne by the concrete beam of the present invention can be directly transmitted to the upper chord node of the steel truss through the multi-directional locking connection key. The force transmission path is shorter and more direct, the force is more clearly defined, and more space is provided for optimizing the cross-sectional form and size of the chord.

[0019] The side support of the present invention is supported at the upper chord node, which can reduce the girder height of the side support, make the transition with the adjacent beam height and make the change of structural rigidity smoother.

[0020] The present invention is not limited to concrete beam-steel truss composite bridges, but is also applicable to other types of composite bridges such as concrete beam-steel box, concrete beam-I-beam, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of the three-dimensional structure of embodiment 1 provided by the present invention; Figure 2 This is a schematic elevation view of the arrangement relationship between the segmental short beam and the multi-directional locking connection key provided by the present invention; Figure 3 This is a plan view of the arrangement relationship between the segmental short beam and the multi-directional locking connection key provided by the present invention; Figure 4 This is a schematic diagram of the cross-sectional structure of the fixed connection key provided by the present invention; Figure 5 This is a schematic diagram of the cross-sectional structure of the longitudinal limited locking connection key provided by the present invention; Figure 6 This is a schematic diagram of the bridge-direction structure of the fixed connection key provided by the present invention; Figure 7 This is a schematic diagram of the longitudinal limited locking connection key provided by the present invention in the along-bridge direction; Figure 8 These are the construction steps of embodiment 1 provided by the present invention; Figure 9 This is a schematic diagram of the three-dimensional structure of embodiment 2 provided by the present invention; Wherein: 1. Concrete beam; 2. Multi-directional locking connector; 2A. Fixed connector; 2A-1. Fixed connector concrete beam embedded part; 2A-2. Steel truss top plate connector; 2A-3. Upper pad; 2A-4. Lower pad; 2A-5. Fixed support steel plate; 2A-6. Fixed connector dust cover; 2B. Longitudinal limited locking connector; 2B-1. Longitudinal limited locking connector concrete beam embedded part; 2B-2. Steel truss upper cross beam top plate connector; 2B-3. Upper sliding support plate; 2B-4. Lower support channel; 2B-5. Longitudinal elastic device; 2B-6. Limited locking connector dust cover; 2B-7. Sliding surface between upper and lower plates; 3. Steel truss beam; 3-1. Upper chord node top plate; 3-2. Upper cross beam top plate; 4. Lower structure; 5. Segmental short beam; 5-1. Beam end tenon; 5-2. Beam end tenon; 6. Expansion joint; 7. Side support; 8. Middle support. DETAILED DESCRIPTION

[0022] Hereinafter, the present invention will be described in detail with reference to the accompanying drawings and embodiments: like Figures 1 to 9As shown, a segmental beam-truss composite bridge using a longitudinal limited locking connecting key includes a concrete beam 1, which is assembled from a number of segmental short beams 5 along the bridge direction. The concrete beam 1 is arranged above the steel truss beam 3 to directly bear the bridge deck load; a multi-directional locking connecting key 2 connecting the segmental short beam 5 and the steel truss beam 3 is provided between the two, and the upper end of the multi-directional locking connecting key 2 is fixed to the embedded part in the segmental short beam 5, and the lower end of the multi-directional locking connecting key 2 is connected to the top plate in the steel truss beam 3.

[0023] The cross-section of the segmented short beam 5 is a π-shaped cross-section or a box-shaped cross-section. An outwardly convex beam end tenon 5-1 is formed on one side of the segmented short beam 5, and an inwardly concave beam end tenon 5-2 is formed on the other side of the segmented short beam 5. The beam end tenons 5-1 and beam end tenons 5-2 between adjacent segmented short beams 5 are overlapped.

[0024] Expansion joints 6 are provided between the segmental short beams 5 , and the segmental short beams 5 are prestressed concrete beams.

[0025] The steel truss 3 includes an upper chord node and an upper cross beam, and the multi-directional locking connection key 2 includes a fixed connection key 2A and a longitudinal limited locking connection key 2B. The fixed connection key 2A connects the upper chord node and the segment short beam 5, and the longitudinal limited locking connection key 2B connects the upper cross beam and the segment short beam 5.

[0026] The fixed connection key 2A includes an upper pad 2A-3, a lower pad 2A-4 and a fixed supporting steel plate 2A-5 vertically connecting the two. The upper pad 2A-3 is fixed to the fixed connection key concrete beam embedded part 2A-1 in the segment short beam 5, and the lower pad 2A-4 is fixed to the upper chord node top plate 3-1.

[0027] The longitudinal limited locking connecting key 2B includes an upper sliding support plate 2B-3 connected to the segment short beam 5 and a lower support groove 2B-4 connected to the upper cross beam top plate 3-2. The upper sliding support plate 2B-3 is inserted into the lower support groove 2B-4, and the two are in contact through the sliding surface 2B-7 between the upper and lower plates.

[0028] A longitudinal elastic device 2B-5 is also provided between the upper sliding support plate 2B-3 and the lower support groove 2B-4.

[0029] The upper end of the upper sliding support plate 2B-3 is fixed to the longitudinal limited locking connection key concrete beam embedded part 2B-1 in the segment short beam 5.

[0030] The lower supporting channel 2B-4 is fixed to the steel truss upper crossbeam top plate connector 2B-2 at the upper end of the upper crossbeam top plate 3-2.

[0031] The steel truss beam 3 is a truss of equal height or variable height. The truss of the steel truss beam 3 adopts a large-span steel truss. A local stiffening structure is provided in the upper chord node of the steel truss to meet the local pressure-bearing requirements.

[0032] Specifically, such as Figure 1 Shown and Figure 9 As shown, Figure 1 To change the height of the truss, Figure 9 The main truss of the steel truss 3 is made of two or more trusses. The side support 7 of the steel truss 3 is supported on the upper chord node, and the middle support 8 of the steel truss 3 is supported on the lower chord node.

[0033] Meanwhile, the concrete beam 1 is composed of segmental short beams 5. The segmental short beams 5 are prestressed concrete beams, prefabricated in a factory, and hoisted and installed on site. The segmental short beams 5 are overlapped by beam end convex tenons 5-1 and beam end concave tenons 5-2, and expansion joints 6 are provided at the connection between the segmental short beams 5.

[0034] Specifically, such as Figure 2 and Figure 3 As shown, the outwardly protruding top of the beam end tenon 5-1 forms an inclined slope, and the width and groove bottom of the beam end tenon 5-2 are consistent with those of the beam end tenon 5-1.

[0035] At the same time, the longitudinal limited locking connection key 2B is arranged at the lower end of the beam end tenon 5-1, and the fixed connection key 2A is arranged on both sides outside the groove of the beam end tenon 5-2.

[0036] Specifically, such as Figure 4 and Figure 6 The fixed connecting key concrete beam embedded part 2A-1 is embedded in the segment short beam 5, and a number of through holes for steel bars to pass through are formed in the fixed connecting key concrete beam embedded part 2A-1. The fixed connecting key concrete beam embedded part 2A-1 provides an embedded fixed foundation.

[0037] Specifically, the upper pad 2A-3 is connected to the concrete beam embedded part 2A-1 by bolts, and the steel truss top plate connector 2A-2 is connected to the lower pad 2A-4. The two can be welded or bolted, and the fixed supporting steel plate 2A-5 is connected to the upper pad 2A-3 and the lower pad 2A-4 by welding.

[0038] At the same time, the dust cover 2A-6 is screwed into the reserved bolt hole of the upper pad 2A-3 by bolts to facilitate later maintenance and replacement.

[0039] Specifically, such as Figure 5 and Figure 7As shown, the longitudinal limited locking connection key concrete beam embedded part 2B-1 is embedded in the beam end tenon 5-1, and a plurality of through holes for steel bars to pass through are formed in the longitudinal limited locking connection key concrete beam embedded part 2B-1. The longitudinal limited locking connection key concrete beam embedded part 2B-1 provides an embedded fixing foundation.

[0040] Specifically, the upper sliding support plate 2B-3 in the longitudinal limited locking connector 2B is connected to the longitudinal limited locking connector concrete beam embedded part 2B-1 through bolts.

[0041] Specifically, the lower supporting channel 2B-4 and the steel truss upper crossbeam top plate connector 2B-2 can be welded or bolted.

[0042] Specifically, an inverted T-shaped steel piece is set in the transverse direction of the upper sliding support plate 2B-3, and two inverted L-shaped steel pieces in opposite directions are set in the transverse direction of the lower support channel 2B-4. The inverted L-shaped steel piece hooks the two flange plates of the inverted T-shaped steel piece to realize the vertical and transverse limiting functions.

[0043] Specifically, the contact surface between the upper sliding support plate 2B-3 and the lower support groove 2B-4 forms a sliding surface 2B-7 between the upper and lower plates, and the sliding surface 2B-7 between the upper and lower plates is composed of two sliding steel plates stacked up and down.

[0044] Specifically, a longitudinal elastic device 2B-5 is provided between the upper sliding support plate 2B-3 and the lower support groove 2B-4 along the bridge direction to achieve a longitudinal limited locking function.

[0045] Specifically, the limited locking connection key dust cover 2B-6 is screwed into the reserved bolt hole of the upper sliding support plate 2B-3 by bolts to facilitate later maintenance and replacement.

[0046] like Figure 8 As shown, the construction process of a segmental beam-truss composite bridge using longitudinal limited locking connectors according to the present invention is as follows: Step 1: construct the lower structure 4 and the steel truss 3. The side support 7 of the steel truss 3 is supported on the upper chord node, and the middle support 8 of the steel truss 3 is supported on the lower chord node.

[0047] Step 2: Synchronously with step 1, prefabricate the segmental short beam 5 in the factory.

[0048] The fixed connecting key concrete beam embedded parts 2A-1 are embedded into the beam body at the designated position, and the concrete is cured, prestressed and placed for a certain period of time in the factory.

[0049] Step 3: Simultaneously with step 1, a multi-directional locking connection key 2 is manufactured in the factory.

[0050] The fixed supporting steel plate 2A-5 of the fixed connecting key 2A is connected to the upper pad 2A-3 and the lower pad 2A-4 by welding, and the fixed connecting key dust cover 2A-6 is screwed into the bolt hole reserved in the upper pad 2A-3 by bolts.

[0051] An inverted T-shaped steel piece is provided on the upper sliding support plate 2B-3 of the longitudinal limited locking connecting key 2B in the transverse bridge direction, and two inverted L-shaped steel pieces in opposite directions are provided on the lower supporting groove 2B-4 in the transverse bridge direction, and the inverted L-shaped steel pieces hook the two flange plates of the inverted T-shaped steel piece; the upper sliding support plate 2B-3 and the lower supporting groove 2B-4 form a sliding surface 2B-7 between the upper and lower plates, and the sliding surface 2B-7 between the upper and lower plates is composed of two sliding steel plates stacked up and down; a longitudinal elastic device 2B-5 is provided between the upper sliding support plate 2B-3 and the lower supporting groove 2B-4 along the bridge direction; the limited locking connecting key dust cover 2B-6 is screwed into the reserved bolt hole of the upper sliding support plate 2B-3 by bolts.

[0052] Step 4: Install the multi-directional locking connection key 2 on the steel truss 3.

[0053] The lower portion of the fixed connection key 2A is installed on the upper chord node top plate 3-1 of the steel truss beam 3 through the steel truss top plate connector 2A-2.

[0054] The lower portion of the longitudinal limited locking connection key 2B is installed on the upper crossbeam top plate 3-2 of the steel truss 3 through the steel truss upper crossbeam top plate connector 2B-2.

[0055] Step five, install the first segmental short beam 5 starting from one side beam end, install the upper pad 2A-3 of the fixed connection key 2A in the fixed connection key concrete beam embedded part 2A-1 with the tenon beam end at the end of the segmental short beam 5 by bolts, and install the upper sliding support plate 2B-3 of the longitudinal limited locking connection key 2B in the longitudinal limited locking connection key concrete beam embedded part 2B-1 with the tenon beam end at the end of the segmental short beam 5 by bolts.

[0056] Step six, match and align the tenon 5-2 at the end of the second beam with the tenon 5-1 at the end of the first beam and drop the beams into place, install the upper pad 2A-3 of the fixed connection key 2A in the fixed connection key concrete beam embedded part 2A-1 with the tenon at the end of the segment short beam 5 by bolts, and install the upper sliding support plate 2B-3 of the longitudinal limited locking connection key 2B in the longitudinal limited locking connection key concrete beam embedded part 2B-1 with the tenon at the end of the segment short beam 5 by bolts.

[0057] Step 7: Complete steps 5 and 6 in sequence until the construction of the concrete beam 1 is completed.

[0058] The above are only preferred embodiments of the present invention and do not limit the present invention in any form. Any ordinary technician in this industry can smoothly implement the present invention as shown in the drawings and above. However, any equivalent changes, modifications and evolutions made by technicians familiar with this profession without departing from the scope of the technical solution of the present invention using the technical content disclosed above are all equivalent embodiments of the present invention. At the same time, any equivalent changes, modifications and evolutions made to the above embodiments based on the essential technology of the present invention are still within the scope of protection of the technical solution of the present invention.

Claims

1. A segmental beam-truss composite bridge using a longitudinal limited locking connector, comprising a concrete beam (1), characterized in that: The concrete beam (1) is composed of a plurality of segmental short beams (5) assembled along the bridge direction. The concrete beam (1) is arranged above the steel truss beam (3) to directly bear the bridge deck load. A multi-directional locking connection key (2) is provided between the segmental short beam (5) and the steel truss beam (3) to connect the two. The upper end of the multi-directional locking connection key (2) is fixed to the embedded part in the segmental short beam (5), and the lower end of the multi-directional locking connection key (2) is connected to the top plate in the steel truss beam (3).

2. The segmental beam-truss composite bridge using longitudinal limited locking connectors according to claim 1, characterized in that: The cross section of the segmented short beam (5) is a π-shaped cross section or a box-shaped cross section, an outwardly convex beam end tenon (5-1) is formed on one side of the segmented short beam (5), and an inwardly concave beam end tenon (5-2) is formed on the other side of the segmented short beam (5), and the beam end tenons (5-1) and beam end tenons (5-2) between adjacent segmented short beams (5) are overlapped.

3. The segmental beam-truss composite bridge using longitudinal limited locking connectors according to claim 1, characterized in that: Expansion joints (6) are provided between the segmented short beams (5), and the segmented short beams (5) are prestressed concrete beams.

4. The segmental beam-truss composite bridge using longitudinal limited locking connectors according to claim 2, characterized in that: The steel truss (3) comprises an upper chord node and an upper crossbeam, and the multidirectional locking connection key (2) comprises a fixed connection key (2A) and a longitudinal limited locking connection key (2B), wherein the fixed connection key (2A) connects the upper chord node and the segment short beam (5), and the longitudinal limited locking connection key (2B) connects the upper crossbeam and the segment short beam (5).

5. The segmental beam-truss composite bridge using longitudinal limited locking connectors according to claim 4, characterized in that: The fixed connection key (2A) comprises an upper pad (2A-3), a lower pad (2A-4) and a fixed support steel plate (2A-5) vertically connecting the two, the upper pad (2A-3) being fixed to a fixed connection key concrete beam embedded part (2A-1) in a segmental short beam (5), and the lower pad (2A-4) being fixed to an upper chord node top plate (3-1).

6. The segmental beam-truss composite bridge using longitudinal limited locking connectors according to claim 4, characterized in that: The longitudinal limited locking connection key (2B) comprises an upper sliding support plate (2B-3) connected to the segment short beam (5) and a lower support groove (2B-4) connected to the upper crossbeam top plate (3-2); the upper sliding support plate (2B-3) is inserted into the lower support groove (2B-4), and the two are in contact through a sliding surface (2B-7) between the upper and lower plates.

7. The segmental beam-truss composite bridge using longitudinal limited locking connectors according to claim 6, characterized in that: A longitudinal elastic device (2B-5) is also provided between the upper sliding support plate (2B-3) and the lower support groove (2B-4).

8. The segmental beam-truss composite bridge using longitudinal limited locking connectors according to claim 6, characterized in that: The upper end of the upper sliding support plate (2B-3) is fixed to the longitudinal limited locking connection key concrete beam embedded part (2B-1) in the segment short beam (5).

9. The segmental beam-truss composite bridge using longitudinal limited locking connectors according to claim 6, characterized in that: The lower supporting channel (2B-4) is fixed to the steel truss upper crossbeam top plate connecting piece (2B-2) at the upper end of the upper crossbeam top plate (3-2).

10. The segmental beam-truss composite bridge using longitudinal limited locking connectors according to claim 1, characterized in that: The steel truss (3) is a uniform height truss or a variable height truss. The truss of the steel truss (3) adopts a large-interval steel truss. A local stiffening structure is provided in the upper chord node of the steel truss to meet the local pressure-bearing requirements.

Images