Jacking bridge and culvert contact net rod relocation and transformation method

Abstract

The invention relates to a bridge and culvert jacking contact network rod moving and changing method. The method comprises the steps that the height H of a bridge and culvert jacking structure and the span L1 of a bridge and culvert jacking structure are determined; the method comprises the following steps: acquiring a friction angle phi in a soil body in a jacking area of a jacking bridge and culvert, determining a fracture angle alpha of the jacking area to be 45 degrees + phi / 2 by adopting a Mohr-Coulomb intensity criterion, and calculating the length L2 of a fracture line in the railway direction to be H * tan alpha according to the fracture angle alpha; the method comprises the steps that a fracture line serves as an excavation stable face in the bridge and culvert jacking process, a span frame crossing the fracture line area is installed in the railway direction, the two ground fixing ends of the span frame are arranged at the positions L3 away from the fracture line end, L3 is the safe distance, and the span of the span frame is L1 + 2 * (L2 + L3); and the existing contact net is installed on the straddle frame according to the original position, composition structure and connection mode of the existing contact net. A permanent and temporary combination method is adopted, normal proceeding of bridge and culvert jacking construction is guaranteed, the contact net rod moving and changing steps are reduced, the railway key point time is shortened, and the influence on railway operation is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of bridge engineering, and particularly to a method for relocating catenary poles of a jacked bridge culvert. Background Art

[0002] Jacking bridges and culverts have the advantages of less land occupation, less demolition volume, less investment, and short construction period, and are widely used in highway and municipal projects for crossing electrified railways. When a bridge or culvert is jacked under an existing railway line, it is necessary to excavate the subgrade soil under the existing railway line to achieve the jacking of the bridge or culvert. The excavation of the soil will inevitably affect the existing railway catenary equipment. To ensure the safe operation of the railway, the railway catenary equipment must be relocated before the jacking construction of the bridge or culvert. In the existing technical solutions, generally, the catenary poles are first moved a certain distance and transitioned onto the railway line reinforcement system or the subgrade protection piles. After the bridge or culvert is jacked into place, the catenary poles are restored in situ. Regarding the relocation of the catenary poles, a patent with the publication number CN107558375B discloses a construction method for the removal and modification of catenary poles during the jacking of a frame bridge, which includes strengthening the railway track, connecting the H-shaped steel to the I-beam of the reinforcement middle beam, installing the temporary catenary poles on the H-shaped steel, relocating the existing catenary power supply system to the temporary catenary poles, then removing the truss of the existing catenary poles. After the frame bridge is jacked into place, the temporary catenary poles are relocated to the steel plates embedded on the frame bridge. After connection, the catenary power supply system is restored, etc. The construction method for the removal and modification of catenary poles during the jacking of the frame bridge provided by the present invention can make the relocated catenary poles and the line reinforcement form a stable system, with the advantages of convenient construction, labor-saving, less manual work, and high construction efficiency. At the same time, it can ensure the safe operation of the railway during the construction process. A patent with the publication number CN106274556B discloses a method for relocating catenary poles, which includes implanting the lower end of the steel truss soft catenary pole into the corner of the crown beam before jacking the frame bridge; temporarily connecting a guy wire to the tops of two corresponding steel truss soft catenary poles on both sides of the railway line; moving the catenary high-voltage wire located on the frame bridge to the guy wire, restoring the operation of the railway line, and jacking the frame bridge according to the traditional jacking method; removing the steel truss soft catenary poles from the protection piles and the crown beam and hoisting them onto the frame bridge, and assembling the lower end with the anchor support foundation; finally, installing a support pole at the upper end of the steel truss soft catenary pole and setting the catenary high-voltage wire on the support pole, etc. The effects of the present invention are: good stability; simple construction, which can reduce the complexity and danger of relocating the catenary poles. It can minimize the impact on the normal operation of the railway and reduce costs. It solves the problem that a large-span frame bridge cannot cross the railway, and the technology is advanced. A patent with the publication number CN215474604U discloses a bilateral hard crossbeam catenary suspension structure, which includes at least two hard crossbeams arranged longitudinally along the bridge. The two ends of the hard crossbeam are respectively connected with hard crossbeam poles, and the hard crossbeam poles are used to be arranged on at least one side of the bridge. Adjacent hard crossbeams are connected by at least two transverse fixing beams. All the transverse fixing beams between the same adjacent hard crossbeams are arranged at intervals longitudinally along the bridge. At least two transverse fixing beams are used to suspend the catenary.Two groups of rigid crossbeams are arranged longitudinally along the bridge. Rigid crossbeam columns are respectively provided at both ends of the rigid crossbeams. A transverse fixing beam is additionally arranged between the rigid crossbeams, and the middle transverse fixing beam is used as the support for hanging and positioning installation, solving the problem that there are no available bridge piers in the existing box girder bridge and the requirements for hanging and positioning installation cannot be met, and making the entire structural form integrated into a whole, improving the structural stability.

[0003] However, the prior art still has the following problems: (1) The combination of temporary and permanent use is not considered. During the jacking of the bridge and culvert, the catenary poles need to be transitioned first and then permanently restored, with a long construction period, a lot of railway key points time, and a greater impact on railway operation; (2) During the transition of the catenary poles, temporary steel frames are used to fix the catenary poles to the railway reinforcement system. Affected by the excavation of the subgrade soil body during the jacking of the bridge and culvert, the railway reinforcement system is in a suspended state, and the deformation of the catenary poles often exceeds the deformation value requirements; (3) The maximum span between the catenary poles in the line direction does not exceed 60 m. When the width of the bridge and culvert exceeds 60 m, due to the control of the catenary span, it is difficult to implement the relocation plan; (4) When the jacking of the bridge and culvert is located in the turnout area, the catenary poles at this time also serve as the positioning poles for the turnout branch line at the same time, and the relocation distance is limited (≤2 m), and it is impossible to relocate to the area outside the influence of the excavation of the jacking bridge and culvert, and it is also difficult to implement the relocation plan. Summary of the Invention

[0004] (I) Technical problems to be solved

[0005] In view of the above-mentioned shortcomings and deficiencies of the prior art, the present invention provides a method for relocating catenary poles of a jacked bridge and culvert.

[0006] (II) Technical solutions

[0007] In order to achieve the above purpose, the method for relocating catenary poles of a jacked bridge and culvert according to the present invention includes:

[0008] S1. Determine the structural height H of the jacked bridge and culvert and the span L1 of the jacked bridge and culvert;

[0009] S2. Obtain the friction angle φ in the soil body of the jacking area of the jacked bridge and culvert, adopt the Mohr-Coulomb strength criterion, determine the rupture angle α = 45° + φ / 2 of the jacking area of the jacked bridge and culvert, and calculate the length L2 = H×tanα of the rupture line along the railway direction according to the rupture angle α;

[0010] S3. Take the rupture line as the excavation stable surface during the jacking of the jacked bridge and culvert, install a cross frame spanning the rupture line area along the railway direction, and the two ground fixed ends of the cross frame are respectively arranged at positions L3 away from the ends of the rupture line, where L3 is a safety distance. Among them, the span L of the cross frame = L1 + 2×(L2 + L3);

[0011] S4. Install the existing contact network onto the cross-frame according to the original position, composition structure and connection method of the existing contact network, so that the cross-frame permanently replaces the contact network pole used to install the existing contact network.

[0012] Optionally, the span frame includes a base, columns, beams and positioning trusses;

[0013] The step of providing a span in the area outside the rupture line along the railway direction includes:

[0014] One base is installed at a position L3 away from the end of the rupture line in the direction of the railway, and one column is installed on each of the two bases to ensure that the central axis of the column is vertical, and the two ends of the beam are connected to the upper ends of the two columns in a one-to-one correspondence; the positioning truss is installed according to the position of the existing contact network in the direction of the railway.

[0015] Optionally, the base includes a bored pile foundation and a reinforced concrete cap, and the bored pile foundation, the reinforced concrete cap and the column are connected in sequence.

[0016] Optionally, the columns are steel truss columns.

[0017] Optionally, the installation of the span includes: constructing a bored pile foundation and a reinforced concrete cap, and simultaneously processing steel truss columns, beams and positioning trusses in a factory;

[0018] After the reinforced concrete foundation reaches the design strength, the steel truss columns, beams and positioning trusses are hoisted and bolted together.

[0019] Optionally, the positioning beam includes an upper positioning rope hanging point and a lower positioning rope hanging point.

[0020] Optionally, installing the existing contact network on the cross frame according to the original position, composition structure and connection method of the existing contact network includes: installing the load-bearing cables of the existing contact network on the crossbeam according to the original position, and installing the upper positioning rope and the lower positioning rope of the existing contact network at the original position to the upper positioning rope suspension point and the lower positioning rope suspension point.

[0021] Optionally, between steps S2 and S3, the following steps are further included:

[0022] The plane position of the span is located according to the position of the existing contact network pole truss, and a safe operating distance S is reserved between the span and the existing contact network pole truss.

[0023] Optionally, after step S5, the method further includes: dismantling the existing contact network pole truss.

[0024] (3) Beneficial effects

[0025] The present invention relates to the relocation of catenary during the jacking of bridges and culverts in electrified railways, and provides a method for relocating catenary poles for jacking bridges and culverts. It is not affected by equipment such as the span of the jacked bridge and culvert and railway turnouts. By adopting the method of combining permanent and temporary facilities, it can not only ensure the normal progress of the jacking bridge and culvert construction, but also reduce the steps of catenary pole relocation, thereby reducing the time required for railway shutdown, and reducing the impact on railway operation. The cross-frame structure has high stiffness and is installed in the area outside the rupture line. During the excavation of the jacked bridge and culvert, the structural deformation is small. This solution can effectively solve the problems existing in the existing catenary relocation, improve the operation efficiency on the premise of ensuring railway safety, provide ideas and calculation methods for future similar projects, and has positive guiding significance. Brief Description of the Drawings

[0026] Figure 1 The flowchart of the method for relocating catenary poles for jacking bridges and culverts of the present invention is as follows:

[0027] Figure 2 It is a plan view of the positional relationship between the jacked bridge and culvert and railway equipment;

[0028] Figure 3 It is a cross-sectional view of the positional relationship between the jacked bridge and culvert and railway equipment;

[0029] Figure 4 It is a longitudinal sectional view of the positional relationship between the jacked bridge and culvert and railway equipment;

[0030] Figure 5 It is a structural schematic diagram of the cross-frame.

[0031]

Description of the Reference Numerals

[0032] 1: Railway track; 3: Jacked bridge and culvert; 5: Truss;

[0033] 6: Cross-frame; 61: Bored pile foundation; 62: Reinforced concrete pile cap; 63: Column; 64: Cross beam; 641: Suspension point for catenary; 642: Suspension point for upper positioning wire; 643: Suspension point for lower positioning wire; 65: Positioning truss. Detailed Embodiments

[0034] In order to better explain the present invention for easy understanding, the present invention will be described in detail below in conjunction with the drawings through specific embodiments. Among them, the orientation nouns such as "upper", "lower", etc. mentioned in this article are referenced with the orientation of Figure 2 .

[0035] Although the exemplary embodiments of the present invention are shown in the drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to enable a clearer and more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0036] As Figure 1 shown, the present invention provides a method for relocating overhead catenary poles of a jacked culvert-bridge, and the method for relocating overhead catenary poles of a jacked culvert-bridge includes:

[0037] Step 1: Determine the structural height H of the jacked culvert-bridge 3 and the span L1 of the jacked culvert-bridge 3;

[0038] Step 2: Obtain the friction angle φ of the soil mass in the jacking area of the jacked culvert-bridge 3, adopt the Mohr-Coulomb strength criterion to determine the rupture angle α = 45° + φ / 2 of the jacking area of the jacked culvert-bridge 3, and calculate the length L2 = H×tanα of the rupture line along the railway direction according to the rupture angle α;

[0039] Step 3: Install a temporary and permanent combined cross-frame 6 along the direction of the existing railway track 1 according to the excavation influence area of the culvert-bridge jacking; specifically, take the rupture line as the excavation stability surface during the jacking process of the jacked culvert-bridge 3, install the cross-frame 6 across the rupture line area along the railway direction, and the two ground fixed ends of the cross-frame 6 are respectively set at positions with a distance L3 from the end of the rupture line, where L3 is a safety distance. Among them, the span L of the cross-frame 6 = L1 + 2×(L2 + L3), and the installation positions of both ends of the cross-frame 6 are placed outside the rupture line, and the span can be customized according to on-site requirements, ensuring that the cross-frame 6 is not affected during the culvert-bridge jacking and is not affected by equipment such as railway turnouts;

[0040] Step 4: Install the existing overhead catenary on the cross-frame 6 according to the original position, composition structure and connection method of the existing overhead catenary, so that the cross-frame 6 permanently replaces the overhead catenary poles for installing the existing overhead catenary. The overhead catenary equipment is relocated outside the influence area of the culvert-bridge at one time as a permanent overhead catenary relocation equipment, and there is no need to reinstall the overhead catenary poles and remove the cross-frame 6 subsequently.

[0041] The present invention provides a method for relocating overhead catenary poles during the process of jacking a culvert-bridge for an electrified railway. It is not affected by equipment such as the span of the jacked culvert-bridge 3 and railway turnouts. Adopting the temporary and permanent combined method can not only ensure the normal progress of the construction of the jacked culvert-bridge 3, but also reduce the steps of relocating the overhead catenary poles, thereby reducing the railway key point time and reducing the impact on railway operation; the cross-frame 6 has a large structural stiffness and is installed in the area outside the rupture line, and the structural deformation is small during the excavation of the culvert-bridge jacking. This solution can effectively solve the problems existing in the existing overhead catenary relocation, improve the operation efficiency on the premise of ensuring railway safety, provide ideas and calculation methods for future similar projects, and has positive guiding significance.

[0042] As Figure 2 and Figure 3 shown, the cross-frame 6 in the method for relocating overhead catenary poles of a jacked culvert-bridge includes a base, a column 63, a cross beam 64 and a positioning truss 65. Setting the cross-frame 6 in the area outside the rupture line along the railway direction includes:

[0043] A base is installed at a position L3 away from both ends of the rupture line in the direction of the railway to ensure that the base is located outside the rupture line and maintains a set safety distance L3 from both ends of the rupture line. A column 63 is installed on each of the two bases to ensure that the central axis of the column 63 is vertical and improve the stability of the column 63. The two ends of the crossbeam 64 are respectively connected to the upper ends of the two columns 63 in a one-to-one correspondence. The crossbeam 64 spans the excavation stabilization surface and forms a new structure with high structural rigidity with the two columns 63, reducing the deformation value of the new structure during the excavation process. The positioning truss 65 is installed according to the position of the existing contact network in the direction of the railway to install the contact network and its ancillary structures, ensuring that the contact network can be installed according to the original position, composition structure and connection method.

[0044] See also Figure 3 The base includes a bored pile foundation 61 and a reinforced concrete pedestal 62. The bored pile foundation 61, the reinforced concrete pedestal 62 and the column 63 are connected in sequence. The bored pile foundation 61 is located in an area outside the excavation stable surface. The depth can be constructed according to the design requirements and is not affected by excavation and jacking, thereby improving the stability of the base.

[0045] In a preferred embodiment, the columns 63 are steel truss columns, which, compared with reinforced concrete structures, reduce their own weight and are easy to install and reuse.

[0046] Furthermore, the installation of the span 6 includes: constructing bored pile foundations 61 and reinforced concrete caps 62 at the construction site after positioning according to the design drawings. At the same time, the steel truss columns, crossbeams 64, and positioning girders 65 are manufactured in the factory according to the installation dimensions. This improves construction efficiency, reduces construction time, and minimizes the impact on railway operations. After the reinforced concrete caps 62 reach the design strength, the steel truss columns, crossbeams 64, and positioning girders 65 are hoisted in sequence and bolted together. Figure 3 and Figure 4 The positioning beam 65 includes an upper positioning rope hanging point 642 and a lower positioning rope hanging point 643, which are used to install the upper positioning rope and the lower positioning rope, replacing the upper positioning rope hanging point 642 and the lower positioning rope hanging point 643 on the original contact network pole.

[0047] The direction along the railway is defined as the longitudinal direction, and the direction of the contact network positioning rope is defined as the transverse direction. Figure 4, in Step 4, installing the existing catenary onto the cross frame 6 according to the original position, composition structure, and connection method of the existing catenary includes: installing the carrier cable of the existing catenary to the carrier cable suspension point 641 on the cross beam 64 according to the original position, and installing the upper positioning rope and the lower positioning rope of the existing catenary to the upper positioning rope suspension point 642 and the lower positioning rope suspension point 643 according to the original position. Wherein, the original position is limited to the longitudinal position. Since the cross frame 6 needs to avoid the original catenary poles and deviates horizontally from the original catenary poles, the original positions of the carrier cable, the upper positioning rope, and the lower positioning rope defined herein refer to the longitudinal position and the horizontal height, and there will be a certain amount of offset horizontally to ensure that the installation process of the cross frame 6 is not interfered by the original catenary poles. Therefore, it is necessary to appropriately extend the carrier cable, the upper positioning rope, and the lower positioning rope.

[0048] See Figure 1 , further, between Step S2 and Step S3, it further includes: positioning the plane position of the cross frame 6 according to the position of the truss 5 on the catenary pole. A safety operation distance S is reserved between the cross frame 6 and the truss 5 on the catenary pole. The safety operation distance S is the distance by which the cross frame 6 deviates horizontally and is also the extension length of the carrier cable, the upper positioning rope, and the lower positioning rope.

[0049] After Step S5, it further includes: removing the truss 5 on the catenary pole, using the cross frame 6 to replace the original catenary pole, and retaining the cross frame 6 after the construction is completed. Using the method of combining permanent and temporary structures, the catenary pole is relocated in one step, which can not only ensure the normal progress of the jacking of the culvert 3, but also reduce the steps of relocating the catenary pole, thereby reducing the time required for railway key points and reducing the impact on railway operation.

[0050] In the description of the present invention, it should be understood that the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, "a plurality of" means two or more unless otherwise specifically defined.

[0051] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "join", "fix", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium; it can be the internal communication of two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0052] In the present invention, unless otherwise clearly specified or limited, when a first feature is "on" or "under" a second feature, it may be that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, when a first feature is "above", "over" and "on top of" a second feature, it may be that the first feature is directly above or obliquely above the second feature, or it merely means that the horizontal height of the first feature is higher than that of the second feature. When a first feature is "under", "below" and "beneath" a second feature, it may be that the first feature is directly below or obliquely below the second feature, or it merely means that the horizontal height of the first feature is lower than that of the second feature.

[0053] In the description of this specification, the descriptions of terms such as "an embodiment", "some embodiments", "embodiments", "examples", "specific examples" or "some examples", etc., mean that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0054] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A method for relocating overhead catenary poles of jacked bridges and culverts, characterized in that, The method for relocating the catenary poles of the jacking bridge culvert includes: S1. Determine the structural height H of the jacking bridge culvert (3) and the span L1 of the jacking bridge culvert (3); S2. Obtain the friction angle φ of the soil mass in the jacking area of the jacking bridge culvert (3). Using the Mohr-Coulomb strength criterion, determine the rupture angle α = 45° + φ / 2 of the jacking area of the jacking bridge culvert (3). Calculate the length L2 of the rupture line along the railway direction as L2 = H × tanα; S3. Take the rupture line as the excavation stable surface during the jacking process of the jacking bridge culvert (3). Install a cross-frame (6) spanning the rupture line area along the railway direction. The two ground fixed ends of the cross-frame (6) are respectively set at positions with a distance L3 from the end of the rupture line. L3 is a safety distance. Among them, the span L of the cross-frame (6) is L = L1 + 2×(L2 + L3); S4. Install the existing catenary on the cross-frame (6) according to the original position, composition structure and connection method of the existing catenary, so that the cross-frame (6) permanently replaces the catenary poles for installing the existing catenary.

2. The jacking bridge culvert catenary pole relocation method according to claim 1, characterized in that, The cross-frame (6) includes a base, columns (63), a cross beam (64) and a positioning truss (65); The installation of the cross-frame (6) in the area outside the rupture line along the railway direction includes: Install one base at each position with a distance L3 from the end of the rupture line along the railway direction. Install one column (63) on each of the two bases, ensure that the central axis of the column (63) is vertical, and respectively connect the two ends of the cross beam (64) to the upper ends of the two columns (63) in one-to-one correspondence; install the positioning truss (65) according to the position of the existing catenary along the railway direction.

3. The jacking bridge culvert catenary pole relocation method according to claim 2, characterized in that The base includes a drilled pile foundation (61) and a reinforced concrete pile cap (62), and the drilled pile foundation (61), the reinforced concrete pile cap (62) and the column (63) are connected in sequence.

4. The jacking bridge culvert catenary pole relocation method according to claim 3, characterized in that, The column (63) is a steel truss column.

5. The method for relocating the catenary poles of the jacking bridge culvert according to claim 4, characterized in that, The installation of the cross-frame (6) includes: constructing the drilled pile foundation (61) and the reinforced concrete pile cap (62), and simultaneously processing the steel truss columns, the cross beam (64) and the positioning truss (65) in the factory; After the reinforced concrete pile cap (62) reaches the design strength, hoist the steel truss columns, the cross beam (64) and the positioning truss (65), and perform bolt connection.

6. The jacking bridge culvert catenary pole relocation method according to claim 2, characterized in that The positioning truss (65) includes an upper positioning rope suspension point (642) and a lower positioning rope suspension point (643).

7. The jacking bridge culvert catenary pole relocation method according to claim 6, wherein, The installation of the existing catenary on the cross-frame (6) according to the original position, composition structure and connection method of the existing catenary includes: installing the catenary's load-bearing cable on the cross beam (64) according to the original position, and installing the upper positioning rope and the lower positioning rope of the existing catenary on the upper positioning rope suspension point (642) and the lower positioning rope suspension point (643) according to the original position.

8. The jacking bridge culvert catenary pole relocation method according to claim 1, characterized in that, Between step S2 and step S3, it further includes: Locate the planar position of the cross frame (6) according to the position of the truss (5) on the catenary pole, and reserve a safe working distance S between the cross frame (6) and the truss (5) on the catenary pole.

9. The jacking bridge culvert catenary pole relocation method according to claim 1, characterized in that, After step S5, it further includes: removing the catenary pole.

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