Prestress reinforcing structure of tunnel fork wall
The composite reinforcement structure consisting of an inner beam frame, an outer arch frame, and a central damping layer solves the stress imbalance problem at the junction wall of the roadway intersection, achieving stress balance and efficient support. It is suitable for mine roadway intersections with poor surrounding rock stability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-04
- Publication Date
- 2026-04-07
AI Technical Summary
Existing technologies for reinforcing the crossroads at roadway intersections with poor surrounding rock stability, large spans, and high mining pressure are complex, costly, and have poor support effects.
The structure employs a composite reinforcement structure consisting of an inner beam frame, an outer arch frame, and a central damping layer. The inner beam frame is composed of load-bearing beams, steel wire ropes, and steel rings. The outer arch frame is composed of prestressed beams, limiting beams, and arc plates. The central damping layer is composed of filling material, and the structure is formed by anchor bolts.
It achieves balanced stress distribution, good support effect, and strong protection capability, and is suitable for roadway intersections with poor surrounding rock stability, reducing construction period and investment costs.
Smart Images
Figure CN224093416U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of mine roadway support technology, specifically a prestressed reinforcement structure for roadway junction walls. Background Technology
[0002] Mine roadway intersections are critical nodes in the transportation and ventilation systems. These locations typically have large spans, and the intersection walls (referred to as "bull's noses" in engineering) are prone to roof collapse and wall deformation due to stress concentration. At transportation roadway intersections, improper operation of transport vehicles can easily cause scraping or collisions with the intersection walls, affecting the stability and safety of the intersection. Therefore, reinforcing the roadway intersection walls is a challenging aspect of mine roadway intersection support.
[0003] Currently, the reinforcement methods for roadway junction walls mostly adopt concrete pillars, anchor cables, and rigid beam supports. Although these methods have a certain reinforcement effect on junction support under different working conditions, they still have the following drawbacks: the construction period of concrete pillar structures is long, affecting the normal production continuity underground, and they are mostly used in junctions with poor surrounding rock stability and long service life; anchor cable supports are difficult to adapt to the three-dimensional spatial stress distribution characteristics of junctions and are prone to prestress loss, and are only suitable for junctions with good surrounding rock stability; rigid beam supports are not easy to coordinate with surrounding rock deformation and are prone to secondary damage, and are mostly used in junctions with poor surrounding rock stability and short service life.
[0004] For roadway intersections with poor surrounding rock stability, large span dimensions, and high mining pressure, there is currently no effective support scheme for reinforcing the intersection walls. Most mines use a combination of the aforementioned reinforcement methods, which achieves the reinforcement effect, but the process is complex and the investment is high. Utility Model Content
[0005] This utility model overcomes the shortcomings of the prior art and proposes a prestressed reinforcement structure for roadway junction walls; it solves the problems of stress imbalance and poor support effect in current mine roadway junction walls.
[0006] To achieve the above objectives, this utility model is implemented through the following technical solution:
[0007] A prestressed reinforcement structure for a roadway junction wall includes an inner beam frame, an outer arch frame, and a damping layer located between the inner beam frame and the outer arch frame. The inner beam frame includes at least two connected load-bearing beams. The load-bearing beams are fixed to the surrounding rock of the junction wall by anchor bolts. The outer arch frame includes multiple prestressed beams, a limiting beam, and an arc-shaped plate. The prestressed beams are horizontally arranged arc-shaped beams, and the prestressed beams are fixedly connected to the load-bearing beams by anchor bolts at the same location. The limiting beams are vertically arranged inside the prestressed beams, and the arc-shaped plate is fixed to the outside of the prestressed beams. The damping layer connects the inner beam frame and the outer arch frame into a single unit.
[0008] Further, the damping layer is a filling body poured between the inner layer beam frame and the outer layer arch frame.
[0009] Further, a pressure bearing beam is arranged at each corner of the turnout wall, and multiple pressure bearing beams are arranged evenly in the middle of the turnout wall.
[0010] Further, the inner layer beam frame further comprises a steel wire rope and a steel ring, and the side wings of the pressure bearing beam are provided with multiple steel rings, and the adjacent two pressure bearing beams are connected by the steel wire rope passing through the steel rings.
[0011] Further, a steel ring is arranged at one wing of the pressure bearing beam at each corner of the turnout wall, and steel rings are arranged at both wings of the pressure bearing beam in the middle of the turnout wall, and the steel rings are arranged at the middle of each section of the upper and lower anchor rods.
[0012] Further, the limiting beam is vertically arranged at the inner side of the middle of the prestressed beam.
[0013] Further, the cross intersection of the limiting beam and the prestressed beam is fixed by iron wire.
[0014] Further, the both ends of the pressure bearing beam and the limiting beam are provided with cushion blocks for supporting the roof and floor at the turnout wall.
[0015] Further, the width of the turnout wall is not less than 1.0 m, and the distance between the outermost side of the limiting beam and the turnout wall is 300 mm to 600 mm.
[0016] The beneficial effects of the utility model relative to the prior art are:
[0017] The utility model adopts the three-in-one composite reinforcing structure of the inner layer beam frame, the outer layer arch frame and the middle damping layer, has the characteristics of balanced stress distribution, good supporting effect and strong protection capability, and can be applied to the roadway intersection point with poor surrounding rock stability, large span size, large mine pressure and long service life.
[0018] (1) The inner layer beam frame is arranged at the turnout wall and multiple pressure bearing beams are arranged, which can effectively support the roof and floor at the turnout wall; the pressure bearing beams are connected into one by the steel wire rope and the steel ring, which can prevent accidents caused by the instability of a pressure bearing beam; the pressure bearing beams are fixed together with the surrounding rock of the turnout wall by the anchor rods, thereby increasing the internal strength of the turnout wall.
[0019] (2) the outer arch is adopted, the prestressed beam is arranged horizontally in an arc shape, a certain stress is applied to the prestressed beam in advance during installation, and good prestressed effect can be achieved; the two ends of the prestressed beam and the bearing pressure beams on the two sides of the turnout wall are fixed through anchor rods at the same position, that is, the outer arch structure and the inner beam structure are connected into one, stress is sequentially transmitted to the surrounding rock through the prestressed beam and the bearing pressure beam when stress is borne, stress distribution is more balanced; the limiting beam is vertically arranged on the inner side of the middle part of the prestressed beam, and can limit the movement of the limiting beam towards the turnout wall; the limiting beam can also assist the bearing pressure beam in supporting the top and bottom plates at the turnout wall; the arc-shaped plate is fixed on the outer side of the prestressed beam, and the outer arch and the inner beam form a closed ring.
[0020] (3) the middle damping layer is adopted, the filling body is poured into the closed ring, the filling body integrates the inner beam and the outer arch, and the integrity and stability of the composite reinforcing structure are increased; the filling body can play a rust-proof role on the metal components in the closed ring, and effectively protect the turnout wall; the filling body also plays a buffering role, and prevents the expansion of an accident when a transport vehicle is scratched or collided. BRIEF DESCRIPTION OF DRAWINGS
[0021] Figure 1 A planar arrangement drawing of the prestressed reinforcing structure of the roadway turnout wall is described in the utility model.
[0022] Figure 2 An enlarged view of the prestressed reinforcing structure is described.
[0023] Figure 3 An elevation arrangement schematic view of the bearing pressure beam is described.
[0024] Figure 4 An elevation arrangement schematic view of the prestressed beam, the limiting beam and the bearing pressure beam is described.
[0025] In the drawing: 1, bearing pressure beam; 2, steel wire rope; 3, steel ring; 4, anchor rod; 5, cushion block; 6, prestressed beam; 7, limiting beam; 8, arc-shaped plate; 9, filling body. DETAILED DESCRIPTION
[0026] In order to make the technical problems, technical schemes and beneficial effects to be solved in the utility model more clear and obvious, the utility model is further described in detail in combination with embodiments and drawings. It should be understood that the specific embodiments described herein are only used to explain the utility model, and are not used to limit the utility model. The technical scheme of the utility model is described in detail below in combination with embodiments and drawings, but the protection scope is not limited by this.
[0027] The main roadway and branch roadway of the intersection of a mine transportation roadway are both in the form of rectangular section, the section size is 4.0m*3.0m, the intersection angle is 45°, and the width of the intersection wall is 2.0m. Since the stability of the surrounding rock at the intersection is poor and the mine pressure is large, the intersection wall adopts the technical scheme provided by the utility model.
[0028] As shown in Figures 1-4 , the embodiment provides a prestressed reinforcement structure of a roadway intersection wall, which comprises an inner layer beam frame, an outer layer arch frame and a middle damping layer, and is composed of a "three-in-one" composite reinforcement structure, and each layer structure is described as follows:
[0029] I. The inner layer beam frame is composed of a plurality of pressure bearing beams 1, steel wires 2 and steel rings 3, the pressure bearing beams 1 are fixed to the intersection wall surrounding rock through anchor rods 4, the pressure bearing beams 1 are provided in 2-4 roots, at least one root is arranged at each corner of the intersection wall, a plurality of steel rings 3 are arranged on the side wing of the pressure bearing beam 1, and the adjacent two pressure bearing beams 1 are connected through the steel rings 3 by the steel wires 2, as shown in Figure 2 、 Figure 3 .
[0030] During on-site construction, the number of the pressure bearing beams 1 should be reasonably determined according to the width of the intersection wall, the mine pressure value and other factors, when the width of the intersection wall is small (less than 1.5m), 2 roots are recommended to be arranged at the corners of the intersection wall, and when the width of the intersection wall is large, 1-2 pressure bearing beams 1 should be additionally arranged in the middle of the intersection wall. The type and model of the steel beam of the pressure bearing beam 1 should be reasonably determined according to the mine pressure value at the intersection wall, the number of the pressure bearing beams 1 and other factors, and channel steel is recommended to be used, the channel opening of the channel steel used at the corners of the intersection wall should be inward, and the channel opening of the channel steel used in the middle of the intersection wall should be outward. The setting interval of the anchor rods 4 is preferably 800mm-1200mm, and the height of the bottom layer of the anchor rods 4 is controlled to be 800mm-1200mm; when the stability of the surrounding rock of the intersection wall is poor, the surrounding rock should be grouted and reinforced first to ensure that the pressure bearing beams 1 are stably fixed to the surrounding rock by the anchor rods 4. One wing of the pressure bearing beam 1 at the corner of the intersection wall is provided with a steel ring 3, and two wings of the pressure bearing beam 1 in the middle of the intersection wall are provided with steel rings 3, and the steel rings 3 are arranged at the middle of each horizontal row of anchor rods 4. The pressure bearing beams 1 are connected into a whole through the steel wires 2 and the steel rings 3, which can prevent accidents caused by the instability of a certain pressure bearing beam 1, and after the pressure bearing beams 1 are stably fixed to the surrounding rock, the internal strength of the intersection wall is improved.
[0031] In the embodiment, the pressure bearing beams 1 are 12# channel steels, the number of which is 3, and the pressure bearing beams 1 are arranged at the corners of the intersection wall and in the middle of the intersection wall; the anchor rods 4 are Φ16*1200mm threaded steel anchor rods, 2 horizontal rows of which are arranged, the height of the lower row is 1000mm, and the height of the upper row is 2000mm; the steel wires 2 and the steel rings 3 are arranged in 3 horizontal rows, and the materials are market-purchased finished products.
[0032] II. Outer arch: composed of a plurality of prestressed beams 6, limiting beams 7, and arc plates 8, the prestressed beams 6 are horizontally arranged arc beams, the two ends of the prestressed beams 6 are fixed between the bearing pressure beams 1 at the two sides of the turnout wall through anchor rods 4 at the same position, the limiting beams 7 are vertically arranged at the inner side of the middle part of the prestressed beams 6, the distance between the outermost side of the limiting beams 7 and the turnout wall is 300mm-600mm, and the arc plates 8 are fixed on the outer side of the prestressed beams 6 to form a closed ring.
[0033] During on-site construction, the type and model of the steel beam of the prestressed beam 6 should be reasonably determined according to factors such as the width of the turnout wall and the stress value to be applied, and a U-shaped steel (with the U opening facing outward) is recommended to be used, the number of the prestressed beams 6 is consistent with the number of the transverse rows of the anchor rods 4. Circular holes are reserved at the two ends of the prestressed beam 6, which are installed on the bearing pressure beams 1 at the two sides of the turnout wall, the exposed section of the shared anchor rod 4 should be appropriately lengthened, the nut for fixing the anchor rod on the original bearing pressure beam 1 should not be removed during installation of the prestressed beam 6, the reserved circular hole of the prestressed beam 6 is sleeved on the exposed section of the shared anchor rod 4, and a new nut is added to fix the prestressed beam 6. The outer arch and the inner beam frame structure are connected as a whole through the shared anchor rod 4, and the stress is sequentially transmitted to the surrounding rock through the prestressed beam 6 and the bearing pressure beam 1 when force is applied, so that the stress distribution is more balanced. One limiting beam 7 is usually used to prevent the prestressed beam 6 from moving towards the turnout wall, so as to enhance the prestressing effect of the prestressed beam 6; the cross intersection between the limiting beam 7 and the prestressed beam 6 can be simply fixed with a wire, and it is not recommended to be arranged with a hole and a bolt, because the hole will affect the strength and prestressing effect of the prestressed beam 6. The curvature value of the prestressed beam 6 should be reasonably determined according to factors such as the width of the turnout wall, the stress value to be applied, and the distance between the limiting beam 7 and the turnout wall. The arc plate 8 is fixed on the outer side of the prestressed beam 6, and the material is recommended to be a thin steel plate, which is welded from multiple pieces, so as to form a closed ring with the outer arch and the inner beam frame, and a filling hole is reserved at the upper end of the arc plate 8, so as to facilitate subsequent pouring of the filling body 9.
[0034] In the embodiment, the prestressed beam 6 is a 18# U-shaped steel, the number of which is 2, and the curvature radius is 2.46m; the limiting beam 7 is a 12# channel steel, the number of which is 1, and the distance between the outermost side of the limiting beam 7 and the turnout wall is 500mm; and the arc plate 8 is welded from multiple pieces of 2mm thin steel plates.
[0035] III. Middle damping layer: formed by pouring the filling body 9 into the closed ring between the outer arch and the inner beam frame. During on-site construction, the filling body 9 is recommended to be a composite fiber material, which is poured into the closed ring through the filling hole reserved at the upper end of the arc plate 8, the filling body 9 pours the inner beam frame and the outer arch as a whole, so as to increase the integrity and stability of the composite reinforced structure; the filling body 9 can play a rust-proof role on the metal components in the closed ring, effectively protecting the turnout wall; and also plays a buffering role to prevent the expansion of the accident when the transport vehicle is scratched or collided.
[0036] In the embodiment, the filler 9 is made of polyurethane fiber composite material, and the elastic modulus is 1.5 GPa.
[0037] Further, the width of the branch wall is not less than 1.0 m; the two ends of the pressure bearing beam 1 and the limiting beam 7 are provided with the cushion block 5 for supporting the top and bottom plate at the branch wall. In the field construction, after the intersection is excavated, the width of the branch wall should be ensured to be not less than 1.0 m, too small is not conducive to the arrangement of the inner beam frame, especially the setting of the anchor rod 4 is easy to break the surrounding rock; of course, it also cannot be too large (limited to 3.0 m), too large will make the maximum span size of the whole intersection larger, which is not conducive to the safety of the intersection support. When the pressure bearing beam 1 and the limiting beam 7 are installed, the two ends of the cushion block 5 should be supported to the real bottom and the real top at the branch wall, so as to fully play the supporting role of the beam.
[0038] Further, the technical scheme provided by the utility model is not only suitable for the reinforcement of the branch wall of the transportation roadway, but also can be applied to the reinforcement of the branch wall of other roadways, and the stress distribution and the supporting effect are the same.
[0039] The above content is a further detailed description of the utility model in combination with the specific preferred embodiment, and the specific embodiment of the utility model cannot be limited to this. For ordinary skilled persons in the technical field to which the utility model belongs, under the premise of not departing from the utility model, a number of simple deductions or substitutions can also be made, which should be regarded as belonging to the utility model, and the patent protection range is determined by the submitted claims.
Claims
1. A prestressed reinforcement structure for a tunnel junction wall, characterized in that, The structure includes an inner beam frame, an outer arch frame, and a damping layer located between the inner beam frame and the outer arch frame. The inner beam frame includes at least two connected load-bearing beams (1). The load-bearing beams (1) are fixed to the surrounding rock of the junction wall by anchor rods (4). The outer arch frame includes multiple prestressed beams (6), a limiting beam (7), and an arc plate (8). The prestressed beams (6) are horizontally arranged arc beams. The prestressed beams (6) and the load-bearing beams (1) are fixedly connected by anchor rods (4) at the same position. The limiting beams (7) are vertically arranged inside the prestressed beams (6), and the arc plate (8) is fixed outside the prestressed beams (6). The damping layer connects the inner beam frame and the outer arch frame into one unit.
2. The prestressed reinforcement structure for a roadway junction wall according to claim 1, characterized in that, The damping layer is a filling material (9) injected between the inner beam frame and the outer arch frame.
3. The prestressed reinforcement structure for a roadway junction wall according to claim 1, characterized in that, A bearing beam is installed at each corner of the fork wall (1); multiple bearing beams are evenly arranged in the middle of the fork wall (1).
4. The prestressed reinforcement structure for a roadway junction wall according to claim 3, characterized in that, The inner beam frame also includes steel wire rope (2) and steel ring (3); multiple steel rings (3) are provided on the side wings of the pressure beam (1), and the steel wire rope (2) passes through the steel ring (3) to connect two adjacent pressure beams (1).
5. A prestressed reinforcement structure for a roadway junction wall according to claim 4, characterized in that, Steel rings (3) are installed on one wing of the bearing beam (1) at the corner of the fork wall, and steel rings (3) are installed on both wings of the bearing beam (1) in the middle of the fork wall. The steel rings (3) are located in the middle of each section above and below each row of anchor rods (4).
6. The prestressed reinforcement structure for a roadway junction wall according to claim 1, characterized in that, The limiting beam (7) is vertically arranged on the inner side of the middle part of the prestressed beam (6).
7. A prestressed reinforcement structure for a roadway junction wall according to claim 1 or 6, characterized in that, The limiting beam (7) and the prestressed beam (6) are fixed with iron wire at their cross intersection.
8. The prestressed reinforcement structure for a roadway junction wall according to claim 1, characterized in that, Both ends of the bearing beam (1) and the limiting beam (7) are provided with pads (5) to support the top and bottom plates at the fork wall.
9. A prestressed reinforcement structure for a roadway junction wall according to claim 1 or 6, characterized in that, The width of the fork wall is not less than 1.0m; the distance between the outermost part of the limiting beam (7) and the fork wall is 300mm~600mm.