Assembly type air duct type ventilation structure of auxiliary tunnel of railway tunnel

Abstract

The invention relates to the technical field of tunnel construction, and discloses a railway tunnel auxiliary tunnel fabricated air duct type ventilation structure which comprises a plurality of supporting cross beams, anchoring assemblies, a plate body assembly and a concrete surface layer, and the multiple supporting cross beams are evenly arranged in the length direction of a tunnel transverse hole; anchoring assemblies are arranged between the two ends of the supporting cross beam and the transverse tunnel lining side wall and comprise anchor rods and brackets, the anchor rods are fixed to the transverse tunnel lining side wall, the brackets are fixed to the anchor rods, the supporting cross beam is transversely erected on the brackets, and the two ends of the supporting cross beam are fixedly connected with the tops of the brackets. The fabricated mode that I-shaped steel, profiled steel sheets and thin-layer concrete are matched with one another is adopted, core components are prefabricated in a factory, installation and connection work are mainly conducted on site, the time for building a huge support, erecting a formwork and most wet work in traditional construction is thoroughly saved, the construction speed is increased by the magnitude order, and the construction period is greatly shortened.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of tunnel construction, in particular to a railway tunnel auxiliary tunnel assembly type air duct ventilation structure. BACKGROUND

[0002] In tunnel construction, auxiliary tunnels such as cross holes are often provided to increase the working face and improve ventilation, and air duct type partitions are constructed therein to achieve zoned ventilation.

[0003] Traditional air duct partitions generally use cast-in-place reinforced concrete structures. Although this structure can ensure strength and airtightness, it has many significant defects in actual construction. First, a large-scale pouring support platform needs to be erected in the cross hole during construction, which not only requires a large amount of materials and labor, but also severely occupies the limited space in the hole. Second, the large construction platform seriously interferes with the continuous vehicle and equipment transportation line in the main hole, posing a high safety risk. Third, the entire process from formwork, steel binding to pouring and maintenance is complicated and time-consuming, becoming a key bottleneck that restricts the construction progress of the main hole. For work areas with extremely strict ventilation requirements such as high-gas tunnels, the traditional construction method is inefficient and high-risk, so there is an urgent need for a new air duct type ventilation structure that can overcome the above-mentioned defects. SUMMARY

[0004] In order to overcome the above-mentioned defects of the prior art, the present application provides a railway tunnel auxiliary tunnel assembly type air duct ventilation structure to solve the problems existing in the background art.

[0005] The present application provides the following technical solution: a railway tunnel auxiliary tunnel assembly type air duct ventilation structure, comprising support beams, anchoring components, plate body components, and a concrete surface layer. The support beams are arranged uniformly along the length direction of the tunnel cross hole, and anchoring components are arranged between the ends of the support beams and the cross hole lining side walls.

[0006] The anchoring component comprises an anchor rod and a corbel. The anchor rod is fixed to the cross hole lining side wall, the corbel is fixed to the anchor rod, the support beam is horizontally arranged on the corbel, and the ends of the support beam are fixedly connected to the top of the corbel. The plate body component comprises a continuously laid profiled steel plate and a steel mesh sheet. The profiled steel plate is laid on the top of the support beam, the steel mesh sheet is laid on the top of the profiled steel plate, and the concrete surface layer is poured on the top of the plate body component.

[0007] Preferably, the anchor rod is a charge anchor rod, which is divided into an anchoring section and an exposed thread section. The anchoring section is fixed in the anchor hole of the cross hole lining side wall by an anchoring agent, the length of the anchoring section is 1.5 m, the corbel is fixed to the exposed thread section by double nuts, and the length of the exposed thread section is 10 cm.

[0008] Preferably, the support cross beam adopts I20a H-shaped steel, the support cross beam is uniformly arranged along the length direction of the transverse hole with a spacing of 2m, and full welding connection is adopted between the two ends of the support cross beam and the top of the corbel.

[0009] Preferably, the model of the profiled steel plate is YX51-253-760, the length of the single plate of the profiled steel plate is 6.1m, the width is 0.76m, the transverse lap length between the adjacent two profiled steel plates is 5cm, and the longitudinal lap length is 10cm.

[0010] Preferably, the profiled steel plate is fixed with the support cross beam through a bolt nail, the diameter of the bolt nail is 13mm, the length is 80mm, and two bolt nails are arranged in the wave groove of each profiled steel plate.

[0011] Preferably, the connection part of the profiled steel plate and the lining side wall of the transverse hole is sealed by a color steel plate.

[0012] Preferably, the steel mesh adopts Φ6 steel bars, and the grid spacing of the steel mesh is 20cm*20cm.

[0013] Preferably, the concrete surface layer is poured by C30 air-tight concrete, and the pouring thickness of the concrete surface layer is 10cm.

[0014] Preferably, every 120m along the length direction of the tunnel transverse hole, a expansion joint is arranged on the top of the support cross beam, the profiled steel plate is welded and fixed at one end and not fixed at the other end, and the concrete surface layer is provided with a 2cm wide construction joint at the expansion joint.

[0015] Preferably, every 200m along the length direction of the tunnel transverse hole, a maintenance opening with a square structure is arranged, the maintenance opening is located at the left and right side walls of the tunnel transverse hole, and the distance between the maintenance opening and the corbel is 10cm.

[0016] The beneficial effects of the present application are as follows: The assembly mode of the H-shaped steel, the profiled steel plate and the thin layer of concrete is adopted, the core components are prefabricated in the factory, the installation and connection operation are mainly carried out on site, the time for setting up large supports, formwork and most of the wet work in the traditional construction is completely saved, the construction speed is improved by orders of magnitude, and the construction period is greatly shortened. The support cross beam, the profiled steel plate and the corbel are all standardized components, the factory production is realized, the component precision and quality stability are ensured, the on-site assembly process is clear, and the construction quality is more easily guaranteed. Without setting up a full-section scaffold platform, the construction occupies a small space, and basically does not affect the normal traffic of vehicles in the main hole, and the cross safety risk of traffic transportation and high-altitude operation in the traditional construction is fundamentally eliminated.

[0017] Through the combination of the anchoring system, the I-shaped steel skeleton and the profiled steel plate, a clear stress system is formed, and the structure is stable; the profiled steel plate is used as a load-bearing formwork, and forms a composite stress body with the post-cast steel mesh and the air-tight concrete, and the overall rigidity and air-tightness can meet the strict requirements of the ventilation of the high-gas tunnel. Although the unit cost of some steel structure components is high, due to the great improvement of the construction efficiency, the reduction of the labor and mechanical investment, the reduction of the safety risk and the great indirect benefits to the main tunnel construction period, the structure has outstanding economic performance in the whole life cycle. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed in the following embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without any creative effort.

[0019] Figure 1 It is a schematic diagram of the overall structure of the present application.

[0020] Figure 2 It is a cooperation diagram of the bracket and the anchor rod of the present application.

[0021] The figure marks are as follows: 1, support beam; 2, anchor rod; 3, bracket; 4, profiled steel plate; 5, steel mesh; 6, concrete surface layer. DETAILED DESCRIPTION

[0022] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific embodiments of the present application will be described in detail below with reference to the drawings of the specification.

[0023] The present application provides a railway tunnel auxiliary tunnel assembly type air channel type ventilation structure, including support beam 1, anchoring assembly, plate body assembly and concrete surface layer 6, the ventilation structure is essentially a kind of installed in tunnel transverse hole, for the permanent assembly type partition plate device of separating tunnel section into two independent air ducts, under the cooperation of fan, upper air duct inhales fresh air, lower air duct removes hole in dirty air, to achieve the purpose of high-gas work area ventilation. Support beam 1, anchoring assembly, plate body assembly and concrete surface layer 6 jointly form a complete stress and sealing system. Support beam 1 is the load-bearing skeleton of the whole ventilation structure, anchoring assembly is arranged between the both ends of support beam 1 and the transverse hole lining side wall, support beam 1 adopts I20a I-shaped steel, support beam 1 is provided with multiple, these support beams 1 are evenly arranged along the length direction of tunnel transverse hole with 2 meters interval, and are transversely arranged in transverse hole.

[0024] The anchoring assembly comprises an anchor rod 2 and a bracket 3, the anchor rod 2 is fixed to the sidewall of the cross-hole lining, the bracket 3 is fixed to the anchor rod 2, the support cross beam 1 is horizontally arranged on the bracket 3, and the two ends of the support cross beam 1 are fixedly connected to the top of the bracket 3, the anchoring assembly is a key component for connecting the support cross beam 1 and the tunnel lining structure, and is responsible for reliably transmitting the load of the overall structure to the surrounding rock. Specifically, the anchor rod 2 is a cartridge anchor rod, the anchor rod 2 is divided into an anchoring section and an exposed thread section, the anchoring section is fixed in the anchor hole of the sidewall of the cross-hole lining by using an anchoring agent, the length of the anchoring section is 1.5 m, the bracket 3 is fixed to the exposed thread section through double nuts, and the length of the exposed thread section is 10 cm; the two ends of the support cross beam 1 are full-welded to the top of the bracket 3, thereby forming a stable portal frame structure.

[0025] The bracket 3 is a force transmission support for connecting the anchor rod 2 and the support cross beam 1, the bracket 3 itself is a component welded by a steel plate, and the typical size of the bracket 3 is a longitudinal length of 20 cm, a transverse length of 30 cm, and a height of 30 cm; in order to enhance the lateral stability, a 16 mm thick inclined support steel plate is usually welded on the bracket 3; the top surface of all the brackets 3 is accurately leveled to ensure that it is at the same design elevation, thereby providing a flat installation base for the support cross beam 1.

[0026] The plate body assembly comprises continuously laid profiled steel plates 4 and steel mesh sheets 5, the profiled steel plates 4 are laid on the top of the support cross beam 1, the steel mesh sheets 5 are laid on the top of the profiled steel plates 4, and a concrete surface layer 6 is poured on the top of the plate body assembly; the plate body assembly constitutes the bottom plate and the stress composite layer of the wind channel partition, and mainly plays the roles of supporting, sealing and working together with the concrete.

[0027] Specifically, the model of the profiled steel plate 4 is YX51-253-760, the length of a single profiled steel plate 4 is 6.1 m, and the width is 0.76 m; the transverse overlap length between two adjacent profiled steel plates 4 is 5 cm, and the longitudinal overlap length is 10 cm, so as to ensure the continuity and compactness of the splicing.

[0028] The profiled steel plate 4 is an open floor slab with a corrugated structure, the wave height of the profiled steel plate 4 is 51 mm, the wave distance is 253 mm, and the coverage width is 760 mm; the plate type is formed by cold rolling and roll pressing of a 1000 mm wide cold-rolled hot-dip galvanized steel plate.

[0029] In order to ensure the reliable combination between the profiled steel plate 4 and the support cross beam 1 and prevent relative slipping, the profiled steel plate 4 is fixed to the support cross beam 1 by means of bolts, the diameter of the bolt is 13 mm, the length of the bolt is 80 mm, and two bolts are arranged in the wave groove of each profiled steel plate 4.

[0030] At the joint between the side edge of the profiled steel plate 4 and the sidewall of the tunnel lining, a color steel plate is arranged as a sealing member, the color steel plate is tightly attached to the sidewall and the edge of the profiled steel plate, and is fixed by a proper method, so as to ensure the air tightness of the joint and prevent air leakage between the upper and lower air ducts.

[0031] On the upper surface of the profiled steel sheet 4, a layer of steel mesh 5 made of Φ6 steel bars is laid, with a grid spacing of 20cm x 20cm, and the meshes are lapped by not less than one grid and tied firmly, which mainly serves to enhance the integrity of the concrete surface layer and suppress shrinkage cracks.

[0032] The concrete surface layer 6 is a functional layer that ensures the flatness, sealing and durability of the top surface of the partition, which is poured with C30 air-tight concrete and is poured on the plate assembly, with a designed thickness of 10cm, which refers to the thickness covering the trough of the profiled steel sheet 4, and the thinnest part of the peak is not less than 5cm, and the layer of concrete finally forms a flat and sealed top surface of the partition.

[0033] To adapt to the special requirements of the tunnel environment, the device also integrates the following auxiliary functional structures: To cope with the expansion and deformation of the structure due to temperature changes, every 120 meters along the length direction of the tunnel transverse hole, a expansion joint is provided on the top of the support beam 1, at this position, one end of the profiled steel sheet 4 is welded and fixed with the support beam 1, and the other end is placed freely in a lapping manner, and the upper concrete surface layer 6 is correspondingly provided with a 2cm wide construction joint.

[0034] To facilitate the maintenance and inspection of the air duct interior in the later period, every 200 meters along the length direction of the tunnel transverse hole, a square access hole is reserved near the left and right side walls of the tunnel, about 10cm away from the corbel 3, with a size of 75cm x 100cm.

[0035] The working principle of the present application: in the actual construction process, the staff can first use the total station instrument to accurately measure and lay out, according to the transverse hole section size and the design elevation of the air duct partition, on the lining side walls on both sides of the transverse hole, along the length direction of the tunnel, every 2m apart, the installation position of each row of corbels 3 is positioned, and the anchor hole position is measured and set on the side wall corresponding to the position of each row of corbels 3, and the left and right sides need to be arranged symmetrically.

[0036] According to the measurement positioning point, the anchor hole is drilled with a wind gun, the hole depth is 1.5m, the hole diameter is matched with the anchor rod 2, after the hole is formed, high-pressure air is used to thoroughly clean the hole to ensure that there is no dust and debris in the hole, after cleaning the hole, 2350 type anchoring agent is immediately filled into the anchor hole, then the anchoring section of the anchor rod 2 is pressed against the anchoring agent, and slowly sent into the hole, after the connecting sleeve is put on, the anchor rod machine is started, and the anchor rod 2 is uniformly and continuously pushed into the hole bottom, to ensure that the anchoring agent is fully filled and solidified to form reliable anchoring force, after the installation of the anchor rod 2, the length of the anchoring section is 1.5m, and the length of the exposed thread section is 10cm.

[0037] The bracket 3, which is preferably 20 cm long in the longitudinal direction, 30 cm long in the transverse direction, 30 cm high, and provided with a 16 mm thick inclined support steel plate to enhance stability, is sleeved into the exposed thread port section of the anchor rod 2, and is fastened using two 2 cm thick nuts to ensure that the bracket is tightly attached to the surface of the side wall. After preliminary installation, all brackets need to be leveled using a leveling line to ensure that the support surfaces of all brackets are at the same design elevation, laying a foundation for the smooth installation of the subsequent I-beam.

[0038] Using a loader or other in-hole transportation equipment, the I20a I-beam is hoisted as a support beam 1 to the corresponding brackets 3 that have been installed on both sides, and the position of the I-beam is adjusted manually to ensure accurate positioning. After confirming the position, the support beam 1 is connected to the top of the bracket 3 at both ends by full welding. The weld must be full and continuous to ensure reliable force transmission. All support beams 1 are evenly arranged at intervals of 2 m along the longitudinal direction of the transverse tunnel to form a stable space support frame.

[0039] After that, the YX51-253-760 type profiled steel plate 4 produced by the factory is manually laid on top of the support beam 1. When laying, the staff needs to pay attention to the fact that the transverse overlap length between adjacent profiled steel plates 4 is 5 cm, and the longitudinal overlap length is 10 cm. After the profiled steel plate 4 is laid in place, it is immediately fixed to the support beam 1 below using a gun nail gun and Φ13 mm x 80 mm dowels, with two dowels arranged in each wave groove of the profiled steel plate 4.

[0040] To ensure the airtightness of the wind channel and prevent air leakage, ordinary color steel plates are used for sealing treatment at the joints between the profiled steel plate 4 and the tunnel lining side wall. The color steel plates need to be tightly attached to the edge of the profiled steel plate 4 and the side wall, and fixed in an appropriate manner to ensure airtightness without gaps. Above the fixed profiled steel plate 4, a Φ6 steel reinforcement mesh 5 is laid with a grid spacing of 20 cm x 20 cm. The overlap length between the meshes is not less than one grid, and is firmly bound with iron wire to enhance the integrity of the concrete surface layer and prevent cracking.

[0041] After that, C30 air-tight concrete is pumped using a ground pump and poured on top of the reinforcement mesh 5. The designed pouring thickness is 10 cm, and a flat vibrator is used to vibrate the concrete to ensure compactness and exclude air bubbles. After vibration, the surface is manually finished to ensure the flatness and smoothness of the top surface of the wind channel partition to meet the requirement of small ventilation resistance.

[0042] Along the length direction of the tunnel transverse tunnel, a expansion joint is provided every 120 m on the top of the support beam 1. At this point, one end of the profiled steel plate 4 is welded and fixed to the I-beam, and the other end is fixed in a lap joint manner without being fixed to release the temperature stress. The corresponding concrete surface layer 6 is provided with a 2 cm wide construction joint at this point.

[0043] Along the length direction of the tunnel transverse hole, every 200m, at the position of the left and right sidewalls of the tunnel about 10cm above the corbel 3, a square inspection opening with the size of 75cmx100cm is reserved, which facilitates the personnel to enter the air duct interior to perform inspection and maintenance work during operation.

[0044] It should be noted that the above examples are only used to illustrate the technical solutions of the present application and are not limiting. Although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can be modified or replaced equivalently without departing from the spirit and scope of the technical solutions of the present application, and they should be covered in the scope of the claims of the present application.

Claims

1. A prefabricated ventilation duct structure for auxiliary tunnels in railway tunnels, characterized in that, It includes a support beam (1), anchoring components, plate components and concrete surface layer (6); multiple support beams (1) are provided, and multiple support beams (1) are evenly arranged along the length of the tunnel cross passage, and anchoring components are provided between both ends of the support beam (1) and the sidewall of the cross passage lining; The anchoring assembly includes an anchor rod (2) and a corbel (3). The anchor rod (2) is fixed to the side wall of the transverse tunnel lining, and the corbel (3) is fixed to the anchor rod (2). The supporting beam (1) is horizontally erected on the corbel (3), and the two ends of the supporting beam (1) are fixedly connected to the top of the corbel (3). The slab assembly includes a continuously laid profiled steel sheet (4) and a steel mesh (5). The profiled steel sheet (4) is laid on the top of the supporting beam (1), the steel mesh (5) is laid on the top of the profiled steel sheet (4), and the concrete surface layer (6) is poured on the top of the slab assembly.

2. The prefabricated ventilation duct type structure for auxiliary tunnels in railway tunnels according to claim 1, characterized in that, Anchor (2) is a medicated anchor. Anchor (2) is divided into an anchoring section and an exposed thread section. The anchoring section is fixed in the anchor hole of the side wall of the transverse tunnel lining with anchoring agent. The length of the anchoring section is 1.5m. The corbel (3) is fixed to the exposed thread section with double nuts. The length of the exposed thread section is 10cm.

3. The prefabricated ventilation duct structure for auxiliary tunnels in railway tunnels according to claim 2, characterized in that, The supporting beam (1) is made of I20a I-beam. The supporting beam (1) is evenly arranged at a spacing of 2m along the length of the transverse opening. The two ends of the supporting beam (1) are fully welded to the top of the corbel (3).

4. The prefabricated ventilation duct type structure for auxiliary tunnels in railway tunnels according to claim 3, characterized in that, The profiled steel sheet (4) is model YX51-253-760. The length of a single sheet of the profiled steel sheet (4) is 6.1m and the width is 0.76m. The horizontal overlap length between two adjacent profiled steel sheets (4) is 5cm and the longitudinal overlap length is 10cm.

5. The prefabricated ventilation duct type structure for auxiliary tunnels in railway tunnels according to claim 4, characterized in that, The profiled steel sheet (4) is fixed to the support beam (1) by studs. The studs are 13mm in diameter and 80mm in length, and two studs are provided in the corrugations of each profiled steel sheet (4).

6. The prefabricated ventilation duct structure for auxiliary tunnels in railway tunnels according to claim 5, characterized in that, The connection between the profiled steel sheet (4) and the side wall of the transverse tunnel lining is sealed with color steel sheet.

7. A prefabricated ventilation duct structure for auxiliary tunnels in railway tunnels according to claim 6, characterized in that, The steel mesh (5) uses Φ6 steel bars, and the mesh spacing of the steel mesh (5) is 20cm×20cm.

8. A prefabricated ventilation duct type structure for auxiliary tunnels in railway tunnels according to claim 7, characterized in that, The concrete surface layer (6) is made of C30 airtight concrete and the thickness of the concrete surface layer (6) is 10cm.

9. A prefabricated ventilation duct structure for auxiliary tunnels in railway tunnels according to claim 8, characterized in that, Expansion joints are provided at the top of the supporting beam (1) every 120m along the length of the tunnel cross passage. The profiled steel sheet (4) is welded and fixed at one end of the expansion joint and overlapped and not fixed at the other end. The concrete surface layer (6) has a 2cm wide construction joint at the expansion joint.

10. A prefabricated ventilation duct structure for auxiliary tunnels in railway tunnels according to claim 9, characterized in that, A square-shaped inspection port is set every 200m along the length of the tunnel cross passage. The inspection port is located on the left and right side walls of the tunnel cross passage, and the distance between the inspection port and the corbel (3) is 10cm.

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