Reinforced support structure for large-diameter vertical shafts under poor geological conditions
By installing mortar anchors on the shaft wall and paving multi-layer concrete and steel mesh, combined with the steel support structure, the instability of the shaft wall under adverse geological conditions is solved, and the stable support effect of the shaft wall is achieved.
Patent Information
- Application Number
- CN202110626023.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2021-06-04
- Publication Date
- 2025-07-22
- Estimated Expiration
- 2041-06-04
AI Technical Summary
Under unhealthy geological conditions such as faults and interlayer staggered zones, the support of the shaft shaft wall is unstable, especially the well walls of large diameter shafts have safety hazards under ordinary spray anchor support.
Mortar anchors are installed on the shaft wall, and the first concrete layer, the second concrete layer and the third concrete layer are successively paved. A steel mesh and a steel support structure are arranged in the middle. The steel support structure is fixedly connected to the mortar anchor, including a steel support structure composed of the first longitudinal steel bar, annular steel arch frame and annular steel bar.
It enhances the stability of the shaft wall of large diameter shaft under adverse geological conditions, and ensures the surrounding rock stability and support strength of the shaft wall.
Smart Images
Figure CN113216974B_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a reinforced support structure for large-diameter vertical shafts under poor geological conditions, and is applicable to the scope of support for large-diameter vertical shafts under poor geological conditions. Background Art
[0002] When the hydropower station powerhouse is arranged underground, multiple vertical shafts need to be set up for the intake and exhaust air, power transmission, etc. of the underground powerhouse, such as intake vertical shafts, exhaust vertical shafts, and outgoing line vertical shafts, etc. Usually, shotcrete support can be used for the support of vertical shafts. However, under poor geological conditions such as faults and interlayer shear zones and when the excavation section of the vertical shaft is relatively large, there is a possibility of instability in the shaft wall under ordinary shotcrete support. At this time, it is necessary to strengthen the support of the shaft wall to ensure the stability of the surrounding rock of the shaft wall. Summary of the Invention
[0003] The technical problem to be solved by the present invention is: to solve the problem of unstable support of the shaft wall under poor geological conditions such as faults and interlayer shear zones, and to provide a stable reinforced support structure for large-diameter vertical shafts under poor geological conditions.
[0004] The technical solution adopted by the present invention is: a reinforced support structure for large-diameter vertical shafts under poor geological conditions, used for the support of large-diameter vertical shafts under poor geological conditions, having a completed shaft wall after excavation. It is characterized in that: mortar bolts for systematic support are fixedly installed on the shaft wall; a first concrete layer, a second concrete layer, and a third concrete layer are sequentially laid on the shaft wall; a steel mesh is provided between the first concrete layer and the second concrete layer; a steel support structure is provided between the second concrete layer and the third concrete layer, and the steel support structure is fixedly connected to the mortar bolts.
[0005] Preferably, the steel support structure has a first longitudinal steel bar, a second longitudinal steel bar, a circumferential steel arch, and circumferential steel bars. The first longitudinal steel bars are evenly installed on the second concrete layer; several circumferential steel arches are evenly arranged along the longitudinal direction of the longitudinal steel bars on the first longitudinal steel bars; several second longitudinal steel bars are evenly installed inside the circumferential steel arches; and several circumferential steel bars are evenly installed on the second longitudinal steel bars.
[0006] Preferably, several L-shaped tension bars for supporting the circumferential steel arch are provided below the circumferential steel arch. The bottom surface of the L-shaped tension bar is welded to the mortar bolt, and the side surface of the L-shaped tension bar is welded to the outer longitudinal steel bar.
[0007] Preferably, the circumferential steel arch has several I-beams and connecting steel plates. One connecting steel plate is welded to each end of the I-beam, and two adjacent connecting steel plates between two I-beams are fixedly connected by bolts. Several I-beams form a circumferential steel arch through the fixedly connected connecting steel plates.
[0008] The beneficial effects of the present invention are as follows: A first concrete layer, a second concrete layer, and a third concrete layer are paved inside the shaft wall, and a steel mesh for stabilizing the connection between the concrete layers is installed between the concrete layers, strengthening the concrete support strength on the two shaft walls. The steel support structure added between the second concrete layer and the third concrete layer is fixedly connected to the mortar bolt, and the steel support structure is fixedly installed on the concrete layer, enhancing the stability of the surrounding rock of the large-diameter shaft wall under poor geological conditions. BRIEF DESCRIPTION OF THE DRAWINGS
[0009] Figure 1 is the longitudinal sectional view of the present invention.
[0010] Figure 2 is the transverse sectional view of the overall structure of the present invention.
[0011] Figure 3 is the detailed transverse sectional view of the circumferential steel arch frame of the present invention.
[0012] Figure 4 is the detailed longitudinal sectional view of the circumferential steel arch frame of the present invention.
[0013] Figure 5 is the detailed view of the connecting steel plate of the present invention.
[0014] In the figure: 1. Shaft wall, 2. Mortar bolt, 3. First concrete layer, 4. Steel mesh, 5. Second concrete layer, 6. First longitudinal steel bar, 7. Circumferential steel arch frame, 7a. I-beam, 7b. Connecting steel plate, 7c. Bolt, 7d. L-shaped tension bar, 8. Second longitudinal steel bar, 9. Circumferential steel bar, 10. Third concrete layer. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0015] This embodiment is a strengthened support structure for a large-diameter shaft under poor geological conditions, having a completed shaft wall after excavation.
[0016] In this embodiment, mortar bolts for systematic support are fixedly installed on the shaft wall, and the mortar bolts need to extend 450 mm into the shaft wall.
[0017] In this embodiment, a first concrete layer, a second concrete layer, and a third concrete layer are sequentially paved on the shaft wall. A steel mesh is provided between the first concrete layer and the second concrete layer, and a steel support structure is provided between the second concrete layer and the third concrete layer. The steel support structure is fixedly connected to the mortar bolt. The first concrete layer, the second concrete layer, and the third concrete layer are all sprayed with C28 concrete. The thickness of the first concrete layer is 50 mm, the thickness of the second concrete layer is 100 mm, and the thickness of the third concrete layer is 300 mm. In this way, the mortar bolts can be completely covered by the concrete.
[0018] In this embodiment, the steel mesh installed in the first concrete layer and the second concrete layer is a steel mesh with a diameter of 8.
[0019] In this embodiment, the steel support structure has first longitudinal steel bars, second longitudinal steel bars, circumferential steel arch frames and circumferential steel bars. The first longitudinal steel bars are evenly installed on the second concrete layer. The first longitudinal steel bars are made of C28 steel bars, and the spacing between two first longitudinal steel bars is 600 mm. Along the first longitudinal steel bars, a number of circumferential steel arch frames are evenly arranged in the longitudinal direction of the longitudinal steel bars, and the distance between two circumferential steel arch frames is 600 mm. A number of second longitudinal steel bars are evenly installed inside the circumferential steel arch frames. The second longitudinal steel bars are made of C28 steel bars, and the spacing between two second longitudinal steel bars is 600 mm. A number of circumferential steel bars are evenly installed on the second longitudinal steel bars. The circumferential steel bars are made of C28 steel bars, and the spacing between two circumferential steel bars is 300 mm.
[0020] In this embodiment, a number of L-shaped tension bars for supporting the circumferential steel arch frames are provided below the circumferential steel arch frames. The bottom surface of the L-shaped tension bars is welded to the mortar anchor bolts, the side surface of the L-shaped tension bars is welded to the outer longitudinal steel bars, and the L-shaped tension bars are made of C28 steel bars.
[0021] In this embodiment, the circumferential steel arch frame has a number of I-beams and connecting steel plates. A connecting steel plate is welded to each end of the I-beam. Two adjacent connecting steel plates between two I-beams are fixedly connected by bolts. A number of I-beams form a circumferential steel arch frame through the fixedly connected connecting steel plates. The I-beams are I16 I-beams, and the single length of the I-beams does not exceed 9 m.
[0022] The construction principle of this embodiment is as follows: In the shaft wall that has been excavated, the shaft wall is systematically supported by mortar anchor bolts. After the mortar anchor bolts are installed, the shaft wall is initially sprayed with concrete to form a first concrete layer. A steel mesh is installed on the completed first concrete layer, and the concrete is re-sprayed to form a second concrete layer. The first longitudinal steel bars are evenly arranged along the formed second concrete layer. The circumferential steel arch frames are installed on the first longitudinal steel bars. The circumferential steel arch frames are composed of a number of I-beams and connecting steel plates. A connecting steel plate is welded to each end of the I-beam, and the two connecting steel plates are fixedly connected by bolt connection to sequentially connect the two I-beams. A number of L-shaped tension bars are fixedly welded at the lower end of the circumferential steel arch frames. The L-shaped tension bars are fixedly welded to the mortar anchor bolts, and the second longitudinal steel bars are fixedly welded to the side surfaces of the L-shaped tension bars. The circumferential steel bars are evenly and fixedly installed on the ring formed by a number of second longitudinal steel bars. After the steel support structure is completed, the concrete is re-sprayed on the second concrete layer to form a third concrete layer, and the mortar anchor bolts and the steel support structure are completely covered in the concrete.
Claims
1. A reinforced support structure for large-diameter vertical shafts under poor geological conditions, which is used for the support of large-diameter vertical shafts under poor geological conditions and has a vertical shaft wall completed by excavation, and is characterized in that: Mortar bolts for system support are fixedly installed on the shaft wall. A first concrete layer, a second concrete layer, and a third concrete layer are successively laid on the shaft wall. A steel mesh is provided between the first concrete layer and the second concrete layer. A steel support structure is provided between the second concrete layer and the third concrete layer, and the steel support structure is fixedly connected to the mortar bolts; The steel support structure has a first longitudinal steel bar, a second longitudinal steel bar, a circumferential steel arch, and circumferential steel bars. The first longitudinal steel bars are evenly installed on the second concrete layer. A number of circumferential steel arches are evenly provided along the longitudinal direction of the first longitudinal steel bars. A number of second longitudinal steel bars are evenly installed inside the circumferential steel arches. A number of circumferential steel bars are evenly installed on the second longitudinal steel bars; A number of L-shaped tension bars for supporting the circumferential steel arches are provided below the circumferential steel arches. The bottom surface of the L-shaped tension bars is welded to the mortar bolts, and the side surface of the L-shaped tension bars is welded to the outer longitudinal steel bars; The circumferential steel arch has a number of I-beams and connecting steel plates. A connecting steel plate is welded to each end of the I-beam. Two adjacent connecting steel plates between two I-beams are fixedly connected by bolts. A number of I-beams form a circumferential steel arch through the fixedly connected connecting steel plates.