Cantilever beam steel bridge for large-section railway tunnel to span deep karst cave

Abstract

The utility model discloses a cantilever beam steel bridge for a large-section railway tunnel to span a deep karst cave, which comprises a plurality of first steel beams arranged in parallel along the length direction of the tunnel, and one end of each first steel beam is fixed on a bottom plate at the end of the tunnel through a first ground anchor. The other end of the first steel beam is fixed to the excavated tunnel face surrounding rock through a second ground anchor, and a steel plate is laid on the first steel beam. Furthermore, the first steel beam is I-shaped steel. Furthermore, connecting ribs are further included, and the connecting ribs are perpendicularly connected to the first steel beams in a crossed mode. Furthermore, the connecting rib is connected with the first steel beam in a winding mode. Furthermore, second steel beams are further included, and the second steel beams are perpendicularly connected to the bottoms of the first steel beams in a crossed mode. The cantilever beam steel bridge is erected on the karst cave, so that the karst cave is prevented from being backfilled, the construction efficiency is improved, and the construction economy is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of tunnel construction, in particular to a cantilever beam steel bridge for a large-section railway tunnel crossing a deep-cut karst cave. Background Art

[0002] A tunnel is a building built underground or in a mountain for the passage of motor vehicles after laying railways or building roads. In the construction of a tunnel, various situations may be encountered, and different construction methods are usually required to carry out the construction of the tunnel.

[0003] When constructing in karst geological areas, due to various forms of dissolution, caves are often encountered during tunnel construction, and caves have a serious impact on tunnel construction and operation. At present, it is very common for tunnel projects to encounter karst geology. When caves appear at the bottom of the construction tunnel, it is often necessary to use backfilling methods to backfill the caves. However, this method of backfilling caves has low construction efficiency and poor economy. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide a cantilever beam steel bridge for a large-section railway tunnel across a deep-cut cave in response to the deficiencies in the above-mentioned prior art. By erecting the cantilever beam steel bridge on the cave, backfilling of the cave can be avoided, thereby improving construction efficiency and improving the economy of construction.

[0005] In order to solve the above technical problems, the technical solution adopted by the utility model is: a cantilever beam steel bridge for a large-section railway tunnel crossing a deep-cut cave, comprising a plurality of first steel beams arranged in parallel along the length direction of the tunnel, one end of the first steel beam being fixed to the bottom plate of the tunnel end by a first ground anchor, and the other end of the first steel beam being fixed to the surrounding rock of the excavated face by a second ground anchor, and a steel plate being laid above the first steel beam.

[0006] Furthermore, the first steel beam is an I-beam.

[0007] Furthermore, it also includes connecting ribs, which are vertically and cross-connected to the plurality of first steel beams.

[0008] Furthermore, the connecting rib is wound and connected to the first steel beam.

[0009] Furthermore, the first steel beam is composed of a plurality of sub-beams welded end to end in sequence.

[0010] Furthermore, the head ends of the two parallel adjacent sub-beams are not located in a straight line.

[0011] Furthermore, a flange plate and / or a web plate is arranged between the two sub-beams connected end to end, and two ends of the flange plate and / or the web plate are respectively welded to the two sub-beams connected end to end.

[0012] Furthermore, it also includes a second steel beam, which is vertically cross-connected at the bottom of multiple first steel beams.

[0013] Compared with the prior art, the utility model has the following advantages:

[0014] The utility model provides a cantilever beam steel bridge for a large-section railway tunnel crossing a deep karst cave. By erecting the cantilever beam steel bridge on the karst cave, backfilling of the karst cave is avoided, thereby improving construction efficiency and improving the economy of construction.

[0015] The utility model provides a cantilever beam steel bridge for a large-section railway tunnel crossing a deep karst cave. Through the horizontal, vertical and staggered distribution, the workers can bear balanced forces when constructing on it, and the stability can be maintained when the fulcrum of the cantilever beam steel bridge is only on one side.

[0016] The utility model provides a cantilever beam steel bridge for a large-section railway tunnel crossing a deep karst cave, wherein the sub-beams are arranged in parallel and staggered manner, so that even if the first steel beam breaks, the breaking points of the sub-beams will not be on the same straight line, thereby supporting the steel plate when breaking, thereby ensuring the safety of construction workers.

[0017] The technical solution of the utility model is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 The utility model provides a schematic diagram of the overall structure of a cantilever beam steel bridge for a large-section railway tunnel spanning a deep-cut cave.

[0019] Figure 2 It is a cross-sectional schematic diagram of the connection structure of adjacent sub-beams in the utility model.

[0020] Description of reference numerals:

[0021] 1. First steel beam; 2. Connecting ribs; 3. Second steel beam; 4. Sub-beam; 5. Flange plate; 6. Web plate. DETAILED DESCRIPTION

[0022] like Figure 1-2As shown, the utility model provides a cantilever beam steel bridge for a large-section railway tunnel crossing a deep-cut cave, comprising a plurality of first steel beams 1 arranged in parallel along the length direction of the tunnel, one end of the first steel beam 1 being fixed to the bottom plate of the tunnel end by a first ground anchor, and the other end of the first steel beam 1 being fixed to the surrounding rock of the excavated face by a second ground anchor, and a steel plate being laid above the first steel beam 1.

[0023] In the present invention, the first steel beam 1 is an I-beam, which is light in weight and high in strength, and can also bear a large load, so it can be effectively fixed in the cave and has a certain load capacity, meeting the safety requirements of construction personnel.

[0024] The utility model further includes connecting ribs 2, which are vertically crossed and connected to the plurality of first steel beams 1. The connecting ribs 2 are wound and connected to the first steel beams 1. The connecting ribs 2 can not only ensure the connection strength between the plurality of first steel beams 1, but also determine the distance between two parallel adjacent first steel beams 1.

[0025] In the utility model, the first steel beam 1 is composed of a plurality of sub-beams 4 welded end to end in sequence. Among them, the head ends of two parallel adjacent sub-beams 4 are not located in a straight line. A flange plate 5 and / or a web plate 6 are arranged between the two sub-beams 4 connected end to end, and the two ends of the flange plate 5 and / or the web plate 6 are respectively welded to the two sub-beams 4 connected end to end. The flange plate 5 and the web plate 6 can wrap the end portions of the two sub-beams 4 adjacent end to end, and fix them by welding, so that there are multiple welding points, which increases the connection strength of the two sub-beams 4 adjacent end to end.

[0026] The utility model further comprises a second steel beam 3, which is vertically cross-connected at the bottom of the plurality of first steel beams 1. The second steel beam 3 is also an I-beam. The second steel beam 3 can increase the stability of the first steel beam 1.

[0027] In summary, in actual construction, in one of the specific embodiments, the first steel beam 1 of the cantilever steel bridge is made of I22a I-beam, with a length of 18m, a width of 7.1m, an I-beam spacing of 1m, and a Φ22 connecting rib with a spacing of 1.5m at the bottom, welded to the I-beam to form a whole, the connecting rib is a steel bar, and 3 second steel beams 3 are provided with a spacing of 5m for reinforcement connection. The second steel beam 3 is made of 22a I-beam, and an 8mm thick steel plate is laid on the top. The I-beam joints of the adjacent parallel first steel beams 1 are staggered by 4.5m, and the joints are reinforced with steel plates. See Figure 2 , 1.2m high hard edge protection is set on both sides of the cantilever beam steel bridge.

[0028] After the cantilever steel bridge is completed, it is pushed above the cave, with one end close to the rock wall and ground anchors evenly placed within 3m of the other end. The ground anchors are arranged in a plum blossom shape with Φ32 steel bars with a spacing of 1m*1m, and are welded to the I-beam of the cantilever steel bridge. The depth of the anchor is not less than 3m, and M30 cement mortar is poured for anchoring. A counterweight of not less than 1t is evenly piled within 2m of the fixed end of the cantilever steel bridge.

[0029] The above is only a preferred embodiment of the present invention and does not constitute any limitation to the present invention. Any simple modification, change and equivalent structural change made to the above embodiments according to the technical essence of the present invention shall still fall within the protection scope of the technical solution of the present invention.

Claims

1. A cantilever steel bridge for a large-section railway tunnel across a deep-cut cave, characterized in that: The invention comprises a plurality of first steel beams (1) arranged in parallel along the length direction of the tunnel, one end of the first steel beam (1) is fixed to the bottom plate of the tunnel end by a first ground anchor, the other end of the first steel beam (1) is fixed to the surrounding rock of the excavated tunnel face by a second ground anchor, and a steel plate is laid above the first steel beam (1).

2. A cantilever beam steel bridge for a large-section railway tunnel across a deep-cut cave according to claim 1, characterized in that: The first steel beam (1) is an I-beam.

3. A cantilever beam steel bridge for a large-section railway tunnel across a deep-cut cave according to claim 1, characterized in that: It also comprises connecting ribs (2), wherein the connecting ribs (2) are vertically and cross-connected to a plurality of the first steel beams (1).

4. A cantilever beam steel bridge for a large-section railway tunnel crossing a deep-cut cave according to claim 3, characterized in that: The connecting rib (2) is wound and connected to the first steel beam (1).

5. A cantilever steel bridge for a large-section railway tunnel across a deep-cut cave according to claim 1, characterized in that: The first steel beam (1) is composed of a plurality of sub-beams (4) which are welded end to end in sequence.

6. A cantilever beam steel bridge for a large-section railway tunnel crossing a deep-cut cave according to claim 5, characterized in that: The head ends of the two parallel adjacent sub-beams (4) are not located in a straight line.

7. A cantilever beam steel bridge for a large-section railway tunnel crossing a deep-cut cave according to claim 5, characterized in that: A flange plate (5) and / or a web plate (6) is arranged between the two sub-beams (4) connected end to end, and two ends of the flange plate (5) and / or the web plate (6) are respectively welded to the two sub-beams (4) connected end to end.

8. A cantilever beam steel bridge for a large-section railway tunnel crossing a deep-cut cave according to claim 1, characterized in that: It also comprises a second steel beam (3), wherein the second steel beam (3) is vertically cross-connected at the bottom of the plurality of first steel beams (1).

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