Safety system for incremental launching construction of ramp steel box girder curved bridge

Abstract

The utility model discloses a ramp steel box girder curved bridge incremental launching construction safety system, which comprises a plurality of transverse guide rail limiters and counterweight parts, the transverse guide rail limiters are arranged on a pier in pairs, the two transverse guide rail limiters in each group are oppositely arranged on the left side and the right side of the pier, the counterweight parts are arranged on the inner side of a guide beam, and the counterweight parts are arranged on the inner side of the guide beam. The transverse guide rail limiter comprises an inclined part, a horizontal part, a vertical part and a contact buffer part, the inclined part and the vertical part are fixedly connected with the pier, the horizontal part is connected with the top of the inclined part and extends towards the side wall of the steel box girder, the contact buffer part is arranged on the horizontal part, and a safety gap is reserved between the contact buffer part and a web of the steel box girder. According to the utility model, the inverted L-shaped transverse guide rail limiters are adopted, every two transverse guide rail limiters are arranged on the bridge piers in opposite directions, and the moving direction of the steel box girder is limited in a set range through the two transverse guide rail limiters, so that the linear deviation in incremental launching construction is reduced, and the transverse falling risk of the steel box girder is reduced at the same time.

Description

Technical Field

[0001] The utility model relates to the technical field of curved bridge jacking, in particular to a ramp steel box girder curved bridge jacking construction safety system. Background Art

[0002] With the development of three-dimensional urban transportation, curved steel box girder ramp bridges have become widely used. Cities often face complex and confined construction spaces, making it difficult to install hoisting equipment or erect scaffolding, necessitating the use of jacking methods to achieve spans. Crawler jacking is widely used in bridge jacking construction due to its integrated advantages of lifting, translation, and lateral adjustment.

[0003] Currently, there are two implementation methods: one is "linear jacking first, then lateral deviation adjustment." This involves placing jacking devices on both the inside and outside of the temporary pier centerline and jacking at the same speed. When the eccentricity limit is reached, lateral deviation correction is performed and jacking continues until the jacking length is completed. This method has good linear control and high safety, but requires frequent lateral deviation corrections and a long jacking time. The other is "inside-outside differential jacking." This method first calculates the outer and inner jacking distances based on the curvature and radius of the jacking line. The speed ratio is then determined based on these distances, and the oil injection ratio between the inner and outer jacking is determined based on the speed ratio. This allows jacking while fitting the bridge's curve characteristics. This has the advantage of requiring fewer lateral deviation corrections and achieving efficient jacking. However, it requires high coordination of differential speed control for the jacking equipment, resulting in high jacking risks. Furthermore, due to the low weight and large curvature of curved steel box girder bridges, they are particularly susceptible to wind and equipment usage during construction, making overturning stability a prominent issue. Currently, research on overturning stability during construction is insufficient. Therefore, a safety system for jacking construction is needed. Utility Model Content

[0004] The purpose of the present utility model is to overcome the deficiencies in the above-mentioned prior art and to provide a safety system for the jacking construction of a curved bridge with a ramp steel box girder. The system adopts an inverted L-shaped transverse guide rail limiter, and the transverse guide rail limiters are arranged in pairs on temporary piers and bridge piers. The moving direction of the steel box girder is restricted within a predetermined range by the two transverse guide rail limiters, thereby reducing the linear deviation in the jacking construction and the risk of the steel box girder falling laterally.

[0005] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a ramp steel box girder curved bridge jacking construction safety system, including a transverse guide rail limiter and a counterweight, the number of the transverse guide rail limiter is multiple, and the multiple transverse guide rail limiters are arranged in groups of two on the bridge pier, and the two transverse guide rail limiters in each group are arranged on the left and right sides of the bridge pier facing each other so that the steel box girder is located between the two opposite transverse guide rail limiters, the counterweight is arranged on the inner side of the guide beam to increase the weight of the inner side of the guide beam, and the transverse guide rail limiter includes an inclined An inclined portion, a horizontal portion, a vertical portion and a contact buffer, wherein the inclined portion is inclined toward the steel box girder, the bottom of the inclined portion and the bottom of the vertical portion are both fixedly connected to the top of the pier, the vertical portion is located on the side of the inclined portion close to the steel box girder, the top of the vertical portion is connected to the inclined portion, the horizontal portion is connected to the top of the inclined portion and extends toward the side wall of the steel box girder, the contact buffer is provided on the side wall of the horizontal portion close to the steel box girder, and a safety gap is left between the contact buffer and the web of the steel box girder to limit the displacement of the steel box girder.

[0006] Preferably, the counterweight is a side frame counterweight.

[0007] Preferably, the contact buffer is made of elastic material.

[0008] Preferably, the safety gap is 10-100 mm.

[0009] Preferably, the longitudinal node spacing of the guide beam is 2m, and the beam heights of the guide beam along the length direction are 3.25m, 2.25m and 1.25m respectively.

[0010] Preferably, the inclined portion, the horizontal portion and the vertical portion are all made of section steel.

[0011] Compared with the prior art, the present invention has the following advantages:

[0012] 1. The utility model adopts an inverted L-shaped transverse guide rail limiter. The transverse guide rail limiters are arranged in pairs on the temporary piers and bridge piers. The moving direction of the steel box girder is restricted within a predetermined range by the two transverse guide rail limiters, thereby reducing the linear deviation during the jacking construction and the risk of the steel box girder falling laterally.

[0013] 2. The utility model adds counterweights to the inner trusses of the existing guide beam to realize a counterweight-type, asymmetric guide beam, effectively reducing the risk of the inner support reaction force being emptied during the jacking process of the curved bridge, increasing the lateral torsional stiffness of the guide beam, and effectively improving the stress state of the steel box beam under the bending-torsion coupling state.

[0014] 3. The counterweight of the present invention can also be installed on the other side of the guide beam in a reverse curve bridge. It is flexible in application and can realize the use of counterweights for various guide beams.

[0015] 4. The safety system of the utility model has low cost, simple structure, easy use and high safety assurance measures.

[0016] The present invention will be described in further detail below through the accompanying drawings and examples. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the structure of the utility model;

[0018] Figure 2 This is a schematic diagram of the position relationship of the transverse guide rail limiter of the utility model;

[0019] Figure 3 This is a schematic diagram of the connection relationship between the counterweight and the guide beam of the utility model.

[0020] Description of the accompanying drawings:

[0021] 1—Horizontal guide rail limiter; 2—Walking push device;

[0022] 3—Steel box girder; 4—Safety gap; 5—Temporary buttress;

[0023] 6—Counterweight; 7—Guide beam 8—Inclined part;

[0024] 9—horizontal part; 10—vertical part; 11—contact buffer;

[0025] 12—Bridge pier. DETAILED DESCRIPTION

[0026] like Figures 1 to 3 As shown, the utility model discloses a ramp steel box girder curved bridge top-pushing construction safety system, including a transverse guide rail limiter 1 and a counterweight 6. The number of the transverse guide rail limiters 1 is multiple, and the multiple transverse guide rail limiters 1 are arranged in groups of two on the bridge pier. The two transverse guide rail limiters 1 in each group are arranged on the left and right sides of the bridge pier facing each other so that the steel box girder 3 is located between the two transverse guide rail limiters 1 facing each other. The counterweight 6 is arranged on the inner side of the guide beam 7 to increase the weight of the inner side of the guide beam 7. The transverse guide rail limiter 1 includes an inclined portion 8, a horizontal portion 9, and a vertical portion 1 0 and contact buffer 11, the inclined portion 8 is inclined toward the steel box girder 3, the bottom of the inclined portion 8 and the bottom of the vertical portion 10 are fixedly connected to the top of the pier, the vertical portion 10 is located on the side of the inclined portion 8 close to the steel box girder 3, the top of the vertical portion 10 is connected to the inclined portion 8, the horizontal portion 9 is connected to the top of the inclined portion 8 and the horizontal portion 9 extends toward the side wall of the steel box girder 3, the contact buffer 11 is provided on the side wall of the horizontal portion 9 close to the steel box girder 3, and a safety gap 4 is left between the contact buffer 11 and the web of the steel box girder 3 to limit the deviation of the steel box girder 3.

[0027] In this embodiment, the bridge pier includes a temporary supporting pier 5 and a bridge pier column 12. Figure 1 Between the bridge piers 10 and 11 is an assembly area with an assembly bracket. A temporary pier 5 is provided between the bridge piers 11 and 12 to facilitate the support of the guide beam 7. The temporary piers 5 are set according to the distance between the two adjacent bridge piers 12. The transverse guide rail limiter 1 is an inverted L-shaped structure. Each temporary pier 5 is provided with a transverse guide rail limiter 1. Each bridge pier 12 is provided with a transverse guide rail limiter 1. The transverse guide rail limiter 1 is provided on the left and right sides of the temporary pier 5 or the bridge pier 12 and is located on the outside of the walking-type pushing device 2. The vertical end of the transverse guide rail limiter 1 is fixedly connected to the temporary pier 5 or the bridge pier 12. The transverse guide rail limiter 1 is a truncated L-shaped structure. The lateral ends of the limiters 1 are close to each other, and the steel box girder 3 is located on the walking pushing device 2. The steel box girder 3 is pushed to move by the walking pushing device 2. A safety gap 4 is left between the outer sides of the webs on the left and right sides of the steel box girder 3 and the lateral guide rail limiters 1 on the left and right sides of the temporary pier 5 or the bridge pier 12. The lateral guide rail limiters 1 on both sides of the temporary pier 5 or the bridge pier 12 ensure that the pushing direction of the walking pushing device 2 is within the allowable range of the established trajectory; and a counterweight 6 is added to the inner side of the guide beam 7 to achieve the characteristics of high stiffness, heavy weight and lateral asymmetry of the inner side of the guide beam 7. During the pushing process, the reaction force of the inner support of the temporary pier 5 or the bridge pier 12 is significantly adjusted to avoid the risk of the steel box girder 3 falling off.

[0028] Furthermore, the counterweight 6 may be arranged on the other side of the guide beam 7 for reverse curved bridge construction.

[0029] In order to limit the bearing capacity of the transverse guide rail, the transverse horizontal restraint force of the transverse guide rail limiter 1 is made 10% of the longitudinal traction force, ensuring that the transverse guide rail limiter 1 can correct the axis deviation angle of 2 degrees of the steel box girder 3. The contact point between the transverse end of the transverse guide rail limiter 1 and the steel box girder 3 should be located at the first web longitudinal rib above the bottom plate, and the distance between the contact point between the transverse end of the transverse guide rail limiter 1 and the steel box girder 3 and the bottom of the steel box girder 3 is not less than 300mm. The bottom of the inclined portion 8 is horizontal and welded to the embedded steel bars of the temporary buttress 5 or the bridge pier 12, and the top of the inclined portion 8 is close to the web of the box steel beam 3, so that the side wall of the inclined portion 8 has an angle with the horizontal direction; the bottom of the vertical portion 10 is horizontal and welded to the embedded steel bars of the temporary buttress 5 or the bridge pier 12, and the two side walls of the vertical portion 10 are of different heights. The two side walls of the vertical portion 10 are connected to form a bevel, which is tightly attached to the side wall of the inclined portion 8 close to the steel box beam 3 and welded to the side wall of the inclined portion 8 close to the steel box beam 3, so that the vertical portion 10 supports the inclined portion 8 upward, and the inclined portion 8 is away from the temporary buttress 5 or the bridge pier 1 2 is welded to the horizontal part 9, then the vertical part 10 and the inclined part 8 jointly support the horizontal part 9 upward, and the supporting strength of the inclined part 8 to the horizontal part 9 is improved by the vertical part 10, so that the horizontal part 9 is kept in a fixed position, and the contact buffer 11 fixed on the horizontal part 9 is kept in a fixed position. When the walking-type jacking device 2 pushes the steel box girder 3 to move along the direction of the curved bridge, the pushing direction of the walking-type jacking device 2 can be limited to the safety gap 4 through the horizontal parts 9 and the contact buffer 11 on the left and right sides of the steel box girder 3. At the same time, the contact buffer 11 at the end of the horizontal part 9 can also prevent the horizontal part 9 from scratching the steel box girder 3 when it directly contacts the steel box girder 3.

[0030] The counterweight 6 is a side beam counterweight. The counterweight 6 is a standard part with the same shape, weight and material as the steel guide beam of the guide beam 7, which is convenient for on-site processing and assembly connection to achieve green construction.

[0031] In this embodiment, the counterweight 6 is installed on the inner wall of the guide beam 7 so that the inner and outer weights of the guide beam 7 are not equal, that is, the counterweight 6 is arranged on the curve radius side of the guide beam 7 on the bridge to increase the inner support pressure and alleviate the risk of air gapping, and effectively prevent the danger of the beam body tipping over. When the walking jacking device 2 pushes the steel box girder 3 to move along the direction of the curved bridge, as the cantilever length increases, the support reaction force at the top position of the temporary pier 5 and the bridge pier 12 on the inner side of the curved bridge gradually decreases, and the risk of air gapping increases, that is, the risk of the steel box girder 3 tipping over to the outside of the curved bridge increases. Therefore, a counterweight 6 is added to the inner side of the guide beam 7 so that the weight on the inner side of the guide beam 7 is greater than the weight on the outer side to facilitate adjustment of the support reaction force.

[0032] The contact buffer 11 is made of elastic material.

[0033] In this embodiment, the contact buffer 11 is a tire. When the steel box girder 3 is offset, the transverse guide rail limiter 1 contacts the web of the steel box girder 3 using the tire, thereby preventing the horizontal portion 9 of the transverse guide rail limiter 1 from directly contacting the steel box girder 3 and damaging the steel box girder 3.

[0034] The safety gap 4 is 10-100 mm.

[0035] In this embodiment, the safety gap 4 is determined based on the curve radius of the curved bridge, the jacking span of the walking jacking device 2, and the construction deviation limit. Taking the jacking of a curved bridge as an example, the bridge curve radius R = 2862.287m. Based on a maximum jacking distance of 500mm, 210 jacking attempts were conducted. The theoretical offset per attempt was calculated to be 0.04mm, resulting in a total offset of 8.4mm. A safety gap 4 of 10mm per side was set for the transverse guide rail stopper 1, meaning that the contact buffer 11 of the transverse guide rail stopper 1, away from the sidewall of the horizontal portion 9, was 10mm away from the web of the steel box girder 3. During the process of the walking jacking device 2 pushing the steel box girder 3 to move, the movement offset direction of the steel box girder 3 is limited to within 10 mm through the safety gap 4 between the transverse guide rail limiter 1 and the web of the steel box girder 3, so that the walking jacking device 2 can adjust the deviation in time to avoid the occurrence of cumulative deviation. At the same time, the adjustment process of the walking jacking device 2 is reduced, and the safety of the movement of the steel box girder 3 is improved.

[0036] The longitudinal node spacing of the guide beam 7 is 2m, and the beam heights of the guide beam 7 along the length direction are 3.25m, 2.25m and 1.25m respectively.

[0037] The height of the guide beam 7 is set to three variable cross-section heights, which can realize the lightweight cantilever; and it is divided into 2-meter sections for easy on-site assembly.

[0038] The inclined portion 8, the horizontal portion 9 and the vertical portion 10 are all made of section steel.

[0039] The inclined portion 8 , the horizontal portion 9 and the vertical portion 10 have the same width, and the transverse guide rail limiter 1 is formed by welding the inclined portion 8 , the horizontal portion 9 and the vertical portion 10 .

[0040] Take a steel-concrete composite beam bridge with a span of (42+60+45)m and a curvature radius of R=2862.287m as an example. The inner diameter R of the beam bridge is 内 =2859.887m, outer diameter R 外=2864.687m. The steel beams of the bridge are divided into 8 sections, each section is 9-10m long, the length of the steel beam jacking splicing area is 47m, and the maximum cantilever length of the guide beam cantilever area is 45m. The jacking system is arranged as follows: the jacking system of the steel box beam 3 is equipped with 6 sets of jacking brackets and one span assembly bracket, and the jacking brackets are numbered 1#-6# respectively. The length of the steel box beam 3 splicing area is composed of steel pipe columns and longitudinal and transverse distribution beams. There are six groups of walking jacking devices 2, including one group of 3DDT-650 walking jacking devices 2, two groups of 3DDT-400 walking jacking devices 2 and three groups of 3DDT-320 walking jacking devices 2, two in each group. The length of the guide beam 7 is 13m, and the structural form adopts a space truss with a longitudinal node spacing of 2m and a beam height of 3.25m. , 2.25m and 1.25m three sections gradually transition, and the upper and lower chords are T-sections, the webs and horizontal cross-connectors are made of H-shaped steel of HM250*175; after the jacking system is arranged, the guide beam 7 is located on the inner side of the curved bridge truss. A counterweight 6 is added, and two walking jacking devices 2 are set on the temporary pier 5 and the bridge pier 12. The two walking jacking devices 2 push the steel box girder 3 longitudinally or transversely. The two walking jacking devices 2 are equipped with an inverted L-shaped transverse guide rail limiter 1 on the side away from each other. According to the horizontal jacking spacing of 4.8m, the walking jacking device 2 has a jacking stroke of 400mm, and the inner The external jacking distance difference is calculated to be 0.67mm, and the total offset is calculated to be 8mm. The transverse guide limiter 1 is set with a safety gap 4 of 10mm on one side. The vertical part 10 and the inclined part 8 of the transverse guide limiter 1 are fixedly connected to the embedded steel bars on the top of the temporary pier 5 or the bridge pier 12. There is a distance between the side of the vertical part 10 away from the inclined part 8 and the walking jacking device 2. The horizontal part 9 is parallel to the horizontal direction. The end of the horizontal part 9 along the length direction is welded to the top of the inclined part 8 to fix the position of the horizontal part 9. A contact buffer part 11 is provided on the side of the horizontal part 9 close to the steel box girder 3 to prevent the horizontal part 9 from damaging the steel box girder. 3. A safety gap 4 is maintained between the contact buffer 11 at the end of the horizontal portion 9 and the web of the steel box girder 3 on the side away from the horizontal portion 9. The two transverse guide rail limiters 1 on each temporary pier 5 and each bridge pier 12 are arranged facing each other. The two facing transverse guide rail limiters 1 restrict the movement of the steel box girder 3 within a predetermined trajectory. That is, when the walking jacking device 2 pushes the steel box girder 3 to move, the maximum offset of the steel box girder 3 to the left or right does not exceed 10mm. If the offset of the steel box girder 3 reaches 10mm, the walking jacking device 2 will perform an additional transverse correction operation before the next jacking to correct the steel box girder 3. The two facing transverse guide rail limiters 1 restrict the steel box girder 3 within a predetermined trajectory, reducing the linear deviation of the walking jacking device 2 during construction and the number of corrections required by the walking jacking device 2. In addition, adding a counterweight 6 to the inner truss of the guide beam 7 can reduce the risk of the steel box girder 3 falling laterally.

[0041] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any way. Any simple modification, change and equivalent structural transformation made to the above embodiment based on the technical essence of the present invention shall still fall within the scope of protection of the technical solution of the present invention.

Claims

1. A safety system for ramp steel box girder curved bridge jacking construction, characterized by: The invention comprises a transverse guide rail limiter (1) and a counterweight (6), wherein the transverse guide rail limiter (1) is provided in a plurality of groups, and the plurality of transverse guide rail limiters (1) are arranged on the bridge pier in pairs, and the two transverse guide rail limiters (1) in each group are arranged on the left and right sides of the bridge pier facing each other so that the steel box beam (3) is located between the two transverse guide rail limiters (1) facing each other, and the counterweight (6) is arranged on the inner side of the guide beam (7) to increase the weight of the inner side of the guide beam (7), and the transverse guide rail limiter (1) comprises an inclined portion (8), a horizontal portion (9), a vertical portion (10) and a contact buffer (11), wherein the inclined portion (8) is closer to the steel box beam (3). The beam (3) is inclined, the bottom of the inclined portion (8) and the bottom of the vertical portion (10) are both fixedly connected to the top of the pier, the vertical portion (10) is located on the side of the inclined portion (8) close to the steel box beam (3), the top of the vertical portion (10) is connected to the inclined portion (8), the horizontal portion (9) is connected to the top of the inclined portion (8) and the horizontal portion (9) extends toward the side wall of the steel box beam (3), the contact buffer (11) is provided on the side wall of the horizontal portion (9) close to the steel box beam (3), and a safety gap (4) is left between the contact buffer (11) and the web of the steel box beam (3) for limiting the displacement of the steel box beam (3).

2. A ramp steel box girder curved bridge jacking construction safety system according to claim 1, characterized in that: The counterweight (6) is a side frame counterweight.

3. A ramp steel box girder curved bridge jacking construction safety system according to claim 1, characterized in that: The contact buffer (11) is made of elastic material.

4. A ramp steel box girder curved bridge jacking construction safety system according to claim 1, characterized in that: The safety gap (4) is 10-100 mm.

5. A ramp steel box girder curved bridge jacking construction safety system according to claim 1, characterized in that: The longitudinal node spacing of the guide beam (7) is 2m, and the beam heights of the guide beam (7) along the length direction are 3.25m, 2.25m and 1.25m respectively.

6. A ramp steel box girder curved bridge jacking construction safety system according to claim 1, characterized in that: The inclined portion (8), the horizontal portion (9) and the vertical portion (10) are all made of section steel.

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