Isolation reinforcing structure for tunnel underneath passing existing line track
By setting up an isolation and reinforcement structure of arch guards and bored piles when the tunnel is penetrated under the existing line track, the problem of excessive settlement of existing line tracks caused by the tunnel is solved, and the control of surface settlement and operational safety is achieved.
Patent Information
- Application Number
- CN202421969977.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-14
- Publication Date
- 2025-06-24
- Estimated Expiration
- 2034-08-14
AI Technical Summary
When the tunnel passes under the existing wire track, it is easy to cause excessive settlement of the existing wire track, affecting operational safety.
The isolation reinforcement structure is adopted that includes guardrails and bored cast piles. The guardrails are located below the existing line track. The lower end of the bored cast pile extends to the lowest point of the tunnel. The upper load is transferred to the deep soil through the bored cast piles to reduce surface settlement.
Effectively control surface settlement, reduce the impact on the vehicles running above, and ensure the operational safety of existing lines.
Smart Images
Figure CN223017687U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of tunnel construction, and particularly relates to an isolation and reinforcement structure for a tunnel to pass under an existing railway track. Background Technique
[0002] With the continuous development of the transportation network, tunnels will inevitably pass under existing railway lines. Building a tunnel under an existing railway line can reduce the driving distance, shorten the driving time, improve driving safety, protect the natural environment, and increase the utilization rate of tunnel and underground engineering space. During tunnel construction, it is often affected by geological conditions and ground environment. When a tunnel passes under an existing railway line, due to the small net distance between the existing railway line and the tunnel structure below, excessive settlement of the existing railway track is extremely likely to occur during the tunnel passing-under construction. Therefore, auxiliary measures must be adopted during the tunnel passing-under construction to reduce the settlement deformation of the existing railway line and ensure the operation safety of the existing railway line. Summary of the Invention
[0003] In order to solve the problems existing in the prior art, the purpose of the utility model is to provide an isolation and reinforcement structure for a tunnel to pass under an existing railway track. The utility model can control the ground settlement, reduce the impact on the vehicles running above, and ensure the operation safety of the existing railway line when a shallow-buried tunnel passes under an existing railway line at a close distance.
[0004] The technical solution adopted by the utility model is as follows:
[0005] An isolation and reinforcement structure for a tunnel to pass under an existing railway track includes an arch protection provided above the tunnel to be excavated and passed under and below the existing railway track, and bored cast-in-place piles provided on both sides of the tunnel to be excavated and passed under; the upper ends of the bored cast-in-place piles are connected to the arch protection, and the lower ends of the bored cast-in-place piles extend below the lowest point of the tunnel to be excavated and passed under.
[0006] Preferably, the longitudinal section shape of the arch protection is a reasonable arch axis, and the longitudinal section of the arch protection is the intersection surface of the longitudinal plane parallel to the driving direction of the existing railway track and the arch protection.
[0007] Preferably, the arch protection includes a cushion layer, a concrete sleeve arch above the cushion layer, a transverse and longitudinal beam structure arranged between the cushion layer and the concrete sleeve arch, and concrete filled between the cushion layer and the concrete sleeve arch and in the transverse and longitudinal beam structure. The transverse and longitudinal beam structure is connected to the upper ends of the bored cast-in-place piles.
[0008] Preferably, the transverse and longitudinal beam structure includes cross beams and longitudinal beams. The axis of the cross beam presents a reasonable arch axis. Cross beams are provided on the same side of the existing railway track. Both ends of the cross beam are connected to the bored cast-in-place piles. Both ends of the longitudinal beam are connected to the cross beams on both sides of the existing railway track. Along the length direction of the cross beam, a plurality of longitudinal beams are evenly distributed.
[0009] Preferably, among several said longitudinal beams, there are steel pipes and steel pipe piles for grouting.
[0010] Preferably, the steel pipes and the steel pipe piles are distributed alternately.
[0011] Preferably, the cross beam is formed by connecting several I-beams. Connecting plates are welded to the end faces of two adjacent I-beams, and the connecting plates at the adjacent ends of two adjacent I-beams are fixedly connected by connecting bolts.
[0012] Preferably, an elastic cushion plate is arranged between the connecting plates at the adjacent ends of two adjacent I-beams.
[0013] Preferably, the protective arch further includes a lining sprayed at the bottom of the cushion layer. There are stiffening ribs between the lining and the bored cast-in-place pile, and the two ends of the stiffening ribs are respectively fixedly connected to the lining and the bored cast-in-place pile.
[0014] Preferably, the existing line track is a highway with an embankment. The bored cast-in-place piles are arranged outside the embankment, and the lower end of the bored cast-in-place pile is at least three meters lower than the lowest point of the tunnel to be excavated and passed under.
[0015] Compared with the prior art, the beneficial effects of the present utility model are as follows:
[0016] In the present utility model, the lower end of the bored cast-in-place pile extends below the lowest point of the tunnel to be excavated and passed under. Therefore, the upper load can be directly transmitted to the deep soil layer without affecting the tunnel construction. At the same time, the deep soil body has good compactness, increasing the bearing capacity. In addition, the construction of the bored cast-in-place pile is conducive to reducing the influence of the surrounding soil body by the unloading of the tunnel excavation to a certain extent, thereby reducing the influence of the tunnel excavation on the upper existing line track. The upper existing line track can be supported by the protective arch to avoid the settlement of the roadbed at the intersection of the tunnel and the existing line track due to the tunnel excavation. In summary, it can be seen that the present utility model can ensure that when the shallow-buried tunnel passes under the existing line at a short distance, it can control the ground settlement, reduce the influence on the vehicles running above, and ensure the operation safety of the existing line. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure 1 It is a top view of the isolation and reinforcement structure for the tunnel to pass under the existing line track in the embodiment of the present utility model;
[0018] Figure 2 It is a sectional view of the isolation and reinforcement structure for the tunnel to pass under the existing line track in the embodiment of the present utility model (the section is parallel to the formation direction of the highway);
[0019] Figure 3 It is a schematic diagram of the connection between the protective arch and the bored cast-in-place pile in the embodiment of the present utility model;
[0020] Figure 4 It is a detail drawing of the connection between the longitudinal beam and the cross beam in the embodiment of the present utility model;
[0021] Figure 5 This is a schematic diagram of the protective arch structure in the embodiment of the present utility model;
[0022] Figure 6(a) is a schematic front view of the connection of the I-beam of the cross beam in the embodiment of the present utility model; Figure 6(b) is a schematic view in the 1-1 direction of Figure 6(a);
[0023] Figure 7 This is a schematic diagram of the steel flower tube structure adopted in the embodiment of the present utility model.
[0024] In the figure, 1 - expressway; 2 - embankment; 3 - bored cast-in-place pile; 4 - protective arch; 5 - to-be-excavated underpass tunnel; 6 - large pipe shed; 7 - bearing platform; 8 - longitudinal beam; 9 - stiffening rib; 10 - concrete sleeve arch; 11 - connecting steel bar; 12 - I-beam; 13 - cushion layer; 14 - lining; 15 - orifice pipe; 16 - I-beam A; 17 - I-beam B; 18 - expansion bolt; 19 - connecting plate; 20 - connecting bolt; 21 - rubber cushion plate; 22 - grouting hole; 23 - reserved slurry stopping section. Specific implementation manners
[0025] The following will further illustrate the present utility model in conjunction with the accompanying drawings and embodiments.
[0026] See Figure 1 and Figure 2 As shown, the isolation and reinforcement structure for the tunnel to pass under the existing line track in this embodiment includes a protective arch 4 arranged above the to-be-excavated underpass tunnel 5 and below the existing line track, and bored cast-in-place piles 3 arranged on both sides of the to-be-excavated underpass tunnel 5; the upper end of the bored cast-in-place pile 3 is connected to the protective arch 4, and the lower end of the bored cast-in-place pile 3 extends below the lowest point of the to-be-excavated underpass tunnel 5.
[0027] During the construction of the isolation and reinforcement structure for the tunnel to pass under the existing line track in this embodiment, first, a construction space is excavated below the existing line track (such as the expressway 1) to Figure 1Taking the example shown as an example, a construction hole across the width of the highway 1 is dug under the highway 1, and the construction hole completely penetrates the left and right directions of the highway 1; and bored cast-in-place piles 3 are constructed at positions corresponding to the construction holes on both sides of the highway 1. After the bored cast-in-place piles 3 are constructed and the state is stable, the guard arch 4 is constructed in the construction hole. After the construction of the guard arch 4 is completed, the remaining space in the construction hole can also be filled with filling materials. The bored cast-in-place piles 3 are used to support the guard arch 4, and the guard arch 4 is used to support the existing line track (such as the highway 1), so as to avoid large deformation of the highway 1 at the construction hole and ensure the integrity and stability of the structure of the highway 1. In the scheme of this embodiment, the shape of the guard arch 4 is a quadrilateral. According to the angle between the existing line track (such as the highway 1) and the driving direction of the tunnel 5 to be excavated, the guard arch 4 can be a rectangle (vertical situation) or a parallelogram (non-vertical situation). In order to ensure that the guard arch 4 has a more stable state, a bored cast-in-place pile 3 is correspondingly arranged at each corner of the guard arch 4. Of course, a bored pile 3 can be set at each of the two corners of one side of the arch 4, and a bored pile 3 can be set in the middle of the other side. The embodiment of the utility model is described by taking an example that a bored pile 3 is set at each corner of the arch 4.
[0028] As a preferred implementation scheme of the above embodiment, in this embodiment, the longitudinal section shape of the guard arch 4 is a reasonable arch axis. The guard arch 4 of this shape has a strong ability to bear force and can effectively ensure the driving safety of the existing track. In addition, in this direction, the span of the reasonable arch axis is relatively small, which is convenient for construction. The longitudinal section of the guard arch 4 is a longitudinal plane parallel to the driving direction of the existing track (with Figure 1 Taking the direction shown as an example, the longitudinal plane is an intersection plane between a plane perpendicular to the straight plane and parallel to the driving direction of the highway 1 (ie, the up-down direction) and the guard arch 4.
[0029] As a preferred embodiment of the above embodiment, see Figure 2 , Figure 3 and Figure 5 In this embodiment, the arch guard 4 includes a cushion layer 13, a concrete arch sleeve 10 located above the cushion layer 13, a transverse and longitudinal beam structure disposed between the cushion layer 13 and the concrete arch sleeve 10, and concrete filled between the cushion layer 13 and the concrete arch sleeve 10 and in the transverse and longitudinal beam structure, and the transverse and longitudinal beam structure is connected to the upper end of the bored pile 3. Among them, the cushion layer 13 is used as the bottom support plate of the entire arch guard 4 when pouring concrete to support the concrete; the space between the cushion layer 13 and the concrete arch sleeve 10 is the concrete pouring space; the transverse and longitudinal beam structure is the skeleton structure of the entire arch guard 4 and plays a major role in bearing the load.
[0030] As a preferred embodiment of the above embodiment, see Figure 1 - Figure 6(b)In this embodiment, the transverse and longitudinal beam structure includes a transverse beam and a longitudinal beam, the axis of the transverse beam is a reasonable arch axis, and the same side of the existing track is provided with a transverse beam, and both ends of the transverse beam are connected with the bored cast-in-place pile 3, so as to Figure 1 As shown in the figure, the above-mentioned cross beams are arranged on both sides of the highway 1 in the longitudinal direction (i.e., the driving direction), and bored cast-in-place piles 3 are arranged at the upper and lower ends of the cross beams, and the two ends of the longitudinal beam (arranged along the width direction of the highway 1) are connected to the cross beams on both sides of the existing track. Figure 1 In the up and down directions shown in the figure), a plurality of longitudinal beams are evenly distributed.
[0031] As a preferred implementation scheme of the above embodiment, in this embodiment, several of the longitudinal beams include steel pipes and steel flower pipes for grouting, wherein the steel flower pipes can be used to cast concrete in the space between the cushion layer 13 and the concrete arch 10.
[0032] As a preferred implementation scheme of the above embodiment, in this embodiment, steel pipes and steel flower pipes are distributed alternately. This arrangement can be beneficial to uniform distribution of concrete when pouring concrete in the space between the cushion layer 13 and the concrete sleeve arch 10, and can avoid defects such as holes in the concrete as much as possible, thereby ensuring the pouring quality of concrete.
[0033] As a preferred embodiment of the above embodiment, see Figure 5 - Figure 6(b) As shown, in this embodiment, the crossbeam is formed by connecting a plurality of I-beams, and a connecting plate 19 is welded to the end faces of two adjacent I-beams, and the connecting plates 19 at the adjacent ends of the two adjacent I-beams are fixedly connected by connecting bolts 20. In this embodiment, the crossbeam is divided into sections and connected by bolts, which is beneficial to reduce the processing difficulty of the crossbeam and can reduce the overall rigidity of the crossbeam, which can reduce the dual effects of the driving load on the highway and the blasting of the lower tunnel to a certain extent.
[0034] As a preferred implementation of the above embodiment, referring to FIG. 6( a ), in this embodiment, an elastic pad (such as a rubber pad 21 ) is provided between the connecting plates 19 at the adjacent ends of two adjacent I-beams. The elastic pad has a certain buffering effect, which can further reduce the overall rigidity of the crossbeam, and to a certain extent can reduce the dual effects of the driving load on the highway and the blasting of the lower tunnel.
[0035] As a preferred embodiment of the above embodiment, see Figure 3 and Figure 5 In this embodiment, the arch guard 4 also includes a lining 14 sprayed on the bottom of the cushion layer 13, and a stiffening rib 9 is provided between the lining 14 and the bored piles 3. The two ends of the stiffening rib 9 are fixedly connected to the lining 14 and the bored piles 3 respectively.
[0036] As a preferred embodiment of the above embodiment, in this embodiment, the existing line track is a highway 1 with an embankment 2, and the bored cast-in-place piles 3 are arranged outside the embankment 2. The lower end of the bored cast-in-place pile 3 is at least three meters lower than the lowest point of the to-be-excavated underpass tunnel 5. The bored cast-in-place piles 3 arranged in this form can effectively transfer the upper load directly to the deep soil, without affecting the tunnel construction. At the same time, the deep soil has good density, increasing the bearing capacity. In addition, the construction of the bored cast-in-place piles is conducive to reducing the influence of the surrounding soil due to the unloading of the tunnel excavation to a certain extent, thereby reducing the influence of the tunnel excavation on the upper line.
[0037] Embodiment
[0038] The isolation and reinforcement structure for the tunnel to pass under the existing line track in this embodiment includes bored cast-in-place piles 3, large pipe roofs 6, protective arches 4, pile caps 7, linings 14, and a cushion layer 13 is provided at the top of the bored cast-in-place piles. Among them, a pile cap 7 is arranged on the cushion layer 13, the pile cap 7 is connected to the protective arch 4, and then the protective arch 4 is connected to the upper end of the bored cast-in-place pile 3 by using the pile cap 7. A large pipe roof 6 is installed in the protective arch 4. The large pipe roof 6 is a structure in which steel pipes and steel flower pipes are arranged alternately. The soil is grouted through the steel flower pipes to form an arch ring. Shotcrete is sprayed below the cushion layer 13 to form a lining 14, and a stiffening rib 9 structure is made between the lining 14 and the bored cast-in-place pile 3.
[0039] Among them, 4 bored cast-in-place piles 3 are arranged, and two bored cast-in-place piles 3 are arranged on each side of the highway 1. The bored cast-in-place piles 3 are located outside the embankment 2 (as Figure 1 shown, the left bored cast-in-place pile 3 is on the left side of the left embankment 2, and the right bored cast-in-place pile 3 is on the right side of the right embankment 2), as Figure 1 shown, the bored cast-in-place piles 3 located on the upper and lower sides of the to-be-excavated underpass tunnel 5 are arranged parallel to the to-be-excavated underpass tunnel 5 (that is, the connection line of the two upper bored cast-in-place piles 3 is parallel to the driving direction of the to-be-excavated underpass tunnel 5, and the connection line of the two lower bored cast-in-place piles 3 is parallel to the driving direction of the to-be-excavated underpass tunnel 5). The pile length of the bored cast-in-place pile 3 should exceed the bottom of the to-be-excavated underpass tunnel 5 (that is, the lower end of the bored cast-in-place pile 3 should be deeper than the depth of the bottom of the to-be-excavated underpass tunnel 5, generally 3 to 5 meters deep is sufficient). The diameter of the bored cast-in-place pile 3 is set to 1m to ensure the support effect.
[0040] See Figure 3 and Figure 4, the protective arch 4 is mainly composed of I-beams 12, connecting steel bars 11, orifice pipes 15, cushions 13, linings 14, and concrete sleeve arches 10. The steel pipes and steel flower pipes are positioned by welding to the I-beams 12 through the connecting steel bars 11, and the weld length is greater than 5 times the diameter of the steel bars. Among them, the curvature of the connecting steel bars 11 is determined by the orifice pipes 15. The steel pipes and steel flower pipes are inserted into the orifice pipes 15, and the steel pipes / steel flower pipes are positioned and installed through the orifice pipes 15. The I-beams 12 are arranged on the cushions 13, and shotcrete linings 14 are sprayed under the cushions 13. The concrete sleeve arches 10 are poured to form the protective arch structure 4. The thickness of the cushion 13 is 100 mm, and the material is C15 concrete.
[0041] The bearing platform 7 is integrally poured with the protective arch 4, and the length of the lower lining of the protective arch should be greater than the length of the protective arch. The concrete used for the lining 14 and the concrete casing 10 is preferably C30. The bearing platform 7 is connected to the bored cast-in-place pile 3 through the exposed steel bars at the top of the bored cast-in-place pile 3. The protective arch 4 uses 2 rows and 6 segments of I-beams 12 as the large pipe shed positioning structure. The I-beams 12 are connected to the bored cast-in-place pile 3 through expansion bolts 18. The I-beams 12 adopt a segmented splicing structure. As Figure 5 - Figure 6(b) shown, it consists of 2 I-beam As and 1 I-beam B, whose curvatures are different. The three are connected through a connecting steel plate 19 and are respectively welded to the connecting plate 19. The connecting plate 19 is connected through connecting bolts 20. A rubber cushion 21 with a thickness of 30 mm is provided between the two connecting steel plates. The rubber cushion 21 plays a buffering role. There is a lining 14 under the protective arch 4, and a stiffening rib 9 is provided between the lining 14 and the bored cast-in-place pile 3 to strengthen the structural integrity and strength. The stiffening rib 9 is fixed through expansion bolts 18.
[0042] The steel pipes and steel flower pipes are arranged alternately with a spacing of 40 mm. As Figure 7 shown, the steel flower pipes are provided with grouting holes 22 every 150 mm. The grouting holes are arranged in a plum blossom shape. The diameter of the grouting holes 22 is 10 - 16 mm. The ends of the steel flower pipes are conical for easy drilling, and a reserved grout stopping section 23 is provided at the other end to enhance the grout stopping effect. Steel bars are welded on the I-beams for positioning and are fixed through fixing steel bars.
[0043] The lining under the protective arch 4 is up to 400 mm thick and is connected to the bored cast-in-place pile 3 through the stiffening rib 9. The stiffening rib 9 is fixed through expansion bolts 18.
[0044] The utility model has good adaptability to the shallow-buried tunnel passing under the existing line. By setting the protective arch for positioning, inserting the steel flower tube for grouting, connecting the protective arch with the bearing platform and the bearing platform with the bored cast-in-place pile, the utility model has good integrity, and is made into an arch structure, making the structural force reasonable. The stiffening ribs are arranged to ensure the structural safety, and at the same time, the steel consumption is reduced, ensuring the economy of the structure. The bored cast-in-place pile extends deep below the tunnel bottom, directly transferring the upper load to the deep soil layer without affecting the tunnel construction. At the same time, the deep soil has good density, increasing the bearing capacity. In addition, the construction of the bored cast-in-place pile is conducive to reducing the influence of the surrounding soil body by the unloading of the tunnel excavation to a certain extent, thereby reducing the influence of the tunnel excavation on the upper line. Rubber pads are arranged between the steel arch frames, which can reduce the double influence of the upper train load and the lower tunnel blasting to a certain extent. The grouting body formed by grouting also forms a partition for the upper and lower parts of the structure. The construction sequence of driving the steel flower tube first and grouting, and then driving the steel pipe can check the grouting quality. The working pit is excavated on both sides of the embankment, without the need to excavate the road surface, and does not affect the normal progress of road transportation.
Claims
1. An isolation and reinforcement structure for a tunnel under an existing track, characterized in that: It comprises a protective arch (4) arranged above the underpass tunnel (5) to be excavated and below the existing track, and bored cast-in-place piles (3) arranged on both sides of the underpass tunnel (5) to be excavated; The upper end of the bored pile (3) is connected to the protective arch (4), and the lower end of the bored pile (3) extends to below the lowest point of the underpass tunnel (5) to be excavated; The longitudinal cross-section shape of the guard arch (4) is a reasonable arch axis, and the longitudinal cross-section of the guard arch (4) is an intersection of a longitudinal plane parallel to the driving direction of the existing track and the guard arch (4); The protective arch (4) comprises a cushion layer (13), a concrete sleeve arch (10) located above the cushion layer (13), a transverse and longitudinal beam structure arranged between the cushion layer (13) and the concrete sleeve arch (10), and concrete filled between the cushion layer (13) and the concrete sleeve arch (10) and in the transverse and longitudinal beam structure, wherein the transverse and longitudinal beam structure is connected to the upper end of the bored cast-in-place pile (3).
2. The isolation and reinforcement structure for a tunnel under an existing track according to claim 1, characterized in that: The transverse and longitudinal beam structure comprises a transverse beam and a longitudinal beam, the axis of the transverse beam being a reasonable arch axis, a transverse beam being provided on the same side of the existing track, both ends of the transverse beam being connected to the bored cast-in-place piles (3), and both ends of the longitudinal beam being connected to the transverse beams on both sides of the existing track, and a plurality of the longitudinal beams being evenly distributed along the length direction of the transverse beam.
3. The isolation and reinforcement structure for a tunnel under an existing track according to claim 2, characterized in that: Several of the longitudinal beams contain steel pipes and steel flower pipes for grouting.
4. The isolation and reinforcement structure for a tunnel under an existing track according to claim 3, characterized in that: Steel pipes and steel flower pipes are distributed alternately.
5. The isolation and reinforcement structure for a tunnel under an existing track according to claim 2, characterized in that: The crossbeam is formed by connecting a plurality of I-beams, the end faces of two adjacent I-beams are welded with connecting plates (19), and the connecting plates (19) at the adjacent ends of the two adjacent I-beams are fixedly connected by connecting bolts (20).
6. The isolation and reinforcement structure for a tunnel under an existing track according to claim 5, characterized in that: An elastic pad is provided between the connecting plates (19) at the adjacent ends of two adjacent I-beams.
7. The isolation and reinforcement structure for a tunnel under an existing track according to claim 1, characterized in that: The arch guard (4) further comprises a lining (14) sprayed on the bottom of the cushion layer (13), a stiffening rib (9) is provided between the lining (14) and the bored piles (3), and two ends of the stiffening rib (9) are respectively fixedly connected to the lining (14) and the bored piles (3).
8. The isolation and reinforcement structure for a tunnel under an existing track according to claim 1, characterized in that: The existing track is a highway (1) having an embankment (2), the bored piles (3) are arranged outside the embankment (2), and the lower ends of the bored piles (3) are at least three meters lower than the lowest point of the underpass tunnel (5) to be excavated.