Prefabricated assembly type steel arch reinforced supporting device

Abstract

The utility model discloses a prefabricated assembly type steel arch reinforced supporting device which comprises a plurality of steel arches arranged at intervals in the length direction of a tunnel, each steel arch comprises a top arc section made of I-shaped steel and waist line arc sections arranged on the two sides of the top arc section, and the top arc sections and the waist line arc sections are fixedly connected through connecting steel plates. The top arc sections of every two adjacent steel arch frames are welded and fixed into a whole through longitudinal connecting steel bars, feet-lock bolts are fixedly connected to the waist line and arch foot positions of the waist line arc sections, the other ends of the feet-lock bolts are driven into the rock wall to be fixed, and each set of feet-lock bolts comprises first anchor rods flatly inserted into the rock wall and second anchor rods obliquely inserted into the rock wall. The included angle between the first anchor rod and the second anchor rod is set to be 25 degrees. The device can provide reinforced support in the cavern with serious geological defects, can be prefabricated and formed in advance, can effectively save time and reduce cost, and is wide in application range.

Description

Technical Field

[0001] This utility model relates to the field of steel arch frame technology, specifically to a prefabricated assembled steel arch frame reinforcement support device. Background Technology

[0002] During the excavation of water diversion tunnels, adverse geological conditions (such as localized rockfalls, seepage, and weak areas) are frequently encountered. Common methods include pipe roof support or reinforcement with pre-anchor bolts and pre-installed small guide pipes. However, there is a time limit (7-28 days) for anchor bolt grouting to reach the designed strength, during which blasting is prohibited, leading to idle time and significantly increased construction costs. Furthermore, these conventional methods only address general adverse geological conditions or serve a preventative role. When severe geological defects occur (such as severely developed joints and fissures, large-scale collapses, or sudden water inrushes), conventional reinforcement methods cannot provide timely and effective solutions. Therefore, rapidly resuming construction when these geological defects occur is a pressing issue. To address this, a prefabricated, assembled steel arch frame reinforcement support device was designed. Utility Model Content

[0003] To solve the above-mentioned technical problems, this utility model provides a prefabricated assembled steel arch frame reinforcement support device. The steel arch frame is formed by splicing the top arc segment and waist arc segment made of I-beams. Multiple sets of locking anchor rods are set at the waist line and arch foot position of the waist arc segment. Adjacent steel arch frames are connected by longitudinal connecting steel bars, and steel mesh is arranged above them. It provides reinforced support in caverns with serious geological defects. The device can be prefabricated in advance, which can effectively save time, reduce costs, and has a wide range of applications.

[0004] A prefabricated assembled steel arch frame reinforced support device includes multiple steel arch frames spaced apart along the tunnel length. Each steel arch frame includes a top arc segment made of I-beams and waist arc segments on both sides of the top arc segment. The top arc segment and the waist arc segments are fixedly connected by connecting steel plates. The top arc segments of each pair of adjacent steel arch frames are welded together as a whole by longitudinal connecting steel bars. Locking anchor rods are fixedly connected at the waistline and arch foot positions of the waist arc segments. The other end of the locking anchor rods is driven into the rock wall for fixation. Each set of locking anchor rods includes a first anchor rod inserted horizontally into the rock wall and a second anchor rod inserted obliquely into the rock wall. The included angle between the first anchor rod and the second anchor rod is set to 25°.

[0005] A further technical solution is as follows: both the first and second anchor rods are made of C25 steel bars with a length of 4.5cm, and the exposed length of the first and second anchor rods is 36cm.

[0006] A further technical solution is: connecting steel plates are welded to the ends of the top arc segment or the waist arc segment. Multiple φ22 connecting holes are symmetrically opened on the connecting steel plates. After the two adjacent connecting steel plates are aligned and fitted together, they are fully welded and fixed. M20 high-strength bolts are threaded onto the connecting holes of the two connecting steel plates.

[0007] A further technical solution is to leave 10-15cm of original rock at the arch foot of the waistline arc.

[0008] A further technical solution is that a longitudinal steel plate support is fixedly connected to the arch foot of the waistline arc.

[0009] A further technical solution is to arrange multiple steel meshes between two adjacent longitudinal steel bars by welding or tying wire.

[0010] A further technical solution is: the longitudinal connecting bars are made of C22 threaded steel, and the circumferential spacing between two adjacent longitudinal connecting bars is 1m.

[0011] The beneficial effects of this utility model are:

[0012] This utility model utilizes a steel arch frame formed by splicing together a top arc segment and a waist arc segment made of I-beams. The top arc segment is a one-piece arc structure with no gaps in the middle, enabling it to withstand large loads from the top and preventing breakage or cracking, thus reducing safety hazards and accidents. The top arc segment and the waist arc segment are connected by full welding and fixed with high-strength bolts passing through connecting steel plates, increasing the connection's strength. Multiple sets of anchor bolts are installed at the waistline and arch foot positions of the waist arc segment. Each set of anchor bolts includes a horizontally inserted and a diagonally inserted first anchor bolt and a second anchor bolt. The ends of the first and second anchor bolts are anchored into the rock wall, ensuring the steel arch frame fits tightly against the rock wall and forms a unified whole with the surrounding rock, greatly increasing the strength and reliability of the steel arch frame. Adjacent steel arch frames are connected by longitudinal reinforcing bars, with a reinforcing mesh arranged above them, effectively connecting the steel arch frames and forming an arch effect, enhancing the strength of the steel arch frame and effectively improving its ability to withstand loads from the surrounding rock above.

[0013] This utility model device is safe and reliable, has strong bending resistance, is simple and practical, and has a wide range of applications. It can provide strong support when serious geological defects occur during the excavation of water diversion tunnels, highway tunnels, underground buried pipes, and other projects. Furthermore, it is easy to assemble, highly efficient, time-saving, and labor-saving, which can effectively reduce costs. Attached Figure Description

[0014] Figure 1 This is a cross-sectional view of a prefabricated assembled steel arch frame reinforced support device.

[0015] Figure 2 This is a schematic diagram showing the connection between the steel plate and the M20 high-strength bolts.

[0016] Figure 3 This is a schematic diagram of the structure connecting the steel plates.

[0017] Figure 4 This is a schematic diagram of longitudinally connected reinforcing bars on multiple steel arch frames.

[0018] In the picture:

[0019] 1. Steel arch frame; 11. Top arc segment; 12. Waistline arc segment; 2. Connecting steel plate; 21. Connecting hole; 3. Locking foot anchor rod; 31. First anchor rod; 32. Second anchor rod; 4. Longitudinal connecting steel bar; 5. M20 high-strength bolt. Detailed Implementation

[0020] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, illustrating only the basic structure of the present invention, and therefore only show the components relevant to the present invention.

[0021] In the description of this utility model, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the utility model.

[0022] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0023] A prefabricated assembled steel arch frame reinforcement support device, such as Figure 1-4As shown, the structure includes multiple steel arch frames 1 spaced apart along the length of the tunnel. Each steel arch frame 1 includes a top arc segment 11 made of I-beams and waist arc segments 12 located on both sides of the top arc segment 11. The top arc segment 11 and the waist arc segments 12 are fixedly connected by connecting steel plates 2. The top arc segments 11 of each two adjacent steel arch frames 1 are welded and fixed into a whole by longitudinal connecting steel bars 4. Locking anchor rods 3 are fixedly connected at the waistline and arch foot positions of the waist arc segments 12. The other end of the locking anchor rods 3 is driven into the rock wall for fixation. Each set of locking anchor rods 3 includes a first anchor rod 31 inserted horizontally into the rock wall and a second anchor rod 32 inserted obliquely into the rock wall. The included angle between the first anchor rod 31 and the second anchor rod 32 is set to 25°.

[0024] The lengths of the top arc segment 11 and the waist arc segment 12 are determined based on the excavation method of the tunnel (full-section, upper half tunnel, etc.). The arcs of each section of the top arc segment 11 and the waist arc segment 12 should be smooth, and the warping of the plane should be less than 2cm when laid flat, thus ensuring the verticality of the steel arch frame when erected. Specifically, the top arc segment 11 and the waist arc segment 12 are made of I20a I-beams.

[0025] Both the first anchor rod 31 and the second anchor rod 32 are made of C25 steel bars with a length of 4.5cm, and the exposed part of the anchor rod is 36cm long.

[0026] like Figure 2 and Figure 3 As shown, connecting steel plates 2 are welded to the ends of the top arc segment 11 or the waist arc segment 12. Multiple φ22 connecting holes 21 are symmetrically drilled on the connecting steel plates 2. Adjacent connecting steel plates 2 are aligned and fully welded together. The connecting holes 21 of the two connecting steel plates 2 are then fixedly connected by M20 high-strength bolts 5. The full welding connection between the connecting steel plates 2 and the high-strength bolts 5 ensure a stable connection between the top arc segment 11 and the waist arc segment 12 as a whole. Specifically, the dimensions of the connecting steel plate 2 are 23cm × 23cm × 15mm (length × width × height), and four connecting holes 21 are symmetrically arranged about the center line of the connecting steel plate 2.

[0027] A 10-15cm layer of original rock is reserved at the arch foot of the waistline arc segment 12 to ensure that the steel arch frame 1 is placed on a stable base. In a preferred embodiment, to further increase the stability of the steel arch frame 1, a longitudinal steel plate support (not shown in the figure) is fixedly connected at the arch foot of the waistline arc segment 12. When the surrounding rock is weak and water-rich, it can increase the bearing capacity of the base.

[0028] Multiple steel mesh panels are arranged between adjacent longitudinal connecting steel bars by welding or tying wire to form an integral load-bearing structure between the steel arch frames 1. Specifically, the longitudinal connecting steel bars 4 are made of C22 threaded steel, and the circumferential spacing between adjacent longitudinal connecting steel bars 4 is 1m.

[0029] How to use this utility model:

[0030] (1) First, check whether the steel arch frame 1 is qualified. Perform trial assembly on the top arc segment 11 and the waist arc segment 12 and check whether the dimensions are correct, whether the welding of each part is firm, and whether there is any missing welding. If missing welding is found, repair welding should be carried out in time.

[0031] (2) Check whether there is any under-excavation in the excavation section. If there is under-excavation, it should be dealt with in advance to ensure that the steel arch frame 1 is erected in one go. Measure and position the erection position of the steel arch frame 1, as well as the centerline, waistline, and arch foot position (and mark them with paint). Before erecting the steel arch frame 1, spray a layer of concrete (3-5cm) to level it and check the stress release of the surrounding rock.

[0032] (3) During the construction of the steel arch frame 1, the surveyors and technicians stood by the site throughout the process to check the centerline position of the steel arch frame 1 at any time, so as to avoid serious over-excavation and under-excavation caused by the steel arch frame 1 deviating from the centerline. The steel arch frame 1 is perpendicular to the centerline of the tunnel, and the error is controlled within the allowable range.

[0033] (4) Reserve 10-15cm of original rock at the arch foot of steel arch frame 1. When the surrounding rock is soft and water-rich, add longitudinal steel plate pads at the arch foot of steel arch frame 1.

[0034] (5) The excavation trolley is used in conjunction with manual labor for segmented installation. According to the position of the measurement and layout mark, the two sides of the waistline arc segment 12 is fixed first, and the foot anchor rod 3 is used for preliminary fixing (two sets of waistline and arch foot positions for each steel arch frame 1). After fixing, the top arc segment 11 is installed and connected to the connecting steel plate 2 with M20 high-strength bolts 5. After erection, the structural dimensions of each part of the steel arch frame 1 are checked to see if they are correct.

[0035] (6) After all the dimensions of the steel arch frame 1 meet the requirements, tighten all the bolts of the connecting steel plates 2 again to ensure a firm connection.

[0036] (7) To ensure accurate installation of the steel arch frame 1, the steel arch frame 1 should be placed close to the rock wall. After the steel arch frame 1 is erected, longitudinal connecting steel bars 4 should be used to weld the steel arch frames 1 together into a whole. At the same time, anchor rods 3 should be driven in to lock the arch feet and waistline positions (which can be fixed by welding), so that the steel arch frame 1 and the anchor rods 3 share the load. Steel mesh should be added to the longitudinal connecting steel bars 4 to form an integral load-bearing structure between the steel arch frames 1. After the steel arch frame 1 is erected, the arch foot connecting plate of the steel arch frame 1 should be buried with mortar to connect with the lower unit steel arch frame 1.

[0037] Based on the above-described preferred embodiments of this utility model, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the technical concept of this utility model. The technical scope of this utility model is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A prefabricated assembled steel arch frame reinforcement support device, characterized in that, The system includes multiple steel arch frames spaced at intervals along the tunnel length. Each steel arch frame consists of a top arc segment made of I-beams and waist arc segments on both sides of the top arc segment. The top arc segment and the waist arc segments are fixedly connected by connecting steel plates. The top arc segments of each pair of adjacent steel arch frames are welded together as a whole using longitudinal connecting steel bars. Locking anchor rods are fixedly connected at the waistline and arch foot positions of the waist arc segments. The other end of the locking anchor rods is driven into the rock wall for fixation. Each set of locking anchor rods includes a first anchor rod inserted horizontally into the rock wall and a second anchor rod inserted obliquely into the rock wall. The included angle between the first anchor rod and the second anchor rod is set to 25°.

2. The prefabricated assembled steel arch frame reinforced support device according to claim 1, characterized in that, Both the first and second anchor rods are made of C25 steel bars with a length of 4.5cm, and the exposed length of the first and second anchor rods is 36cm.

3. The prefabricated assembled steel arch frame reinforced support device according to claim 1, characterized in that, The ends of the top arc segment or waist arc segment are welded with connecting steel plates. Multiple φ22 connecting holes are symmetrically opened on the connecting steel plates. After the two adjacent connecting steel plates are aligned and fitted together, they are fully welded and fixed. M20 high-strength bolts are threaded onto the connecting holes of the two connecting steel plates.

4. The prefabricated assembled steel arch frame reinforced support device according to claim 1, characterized in that, A 10-15cm section of original rock is reserved at the arch foot of the waistline arc.

5. A prefabricated assembled steel arch frame reinforced support device according to claim 4, characterized in that, The arched foot of the waistline is also fixedly connected with a longitudinal steel plate support.

6. The prefabricated assembled steel arch frame reinforced support device according to claim 1, characterized in that, Multiple steel meshes are arranged between adjacent longitudinal steel bars by welding or tying wire.

7. A prefabricated assembled steel arch frame reinforced support device according to claim 6, characterized in that, The longitudinal connecting bars are made of C22 threaded steel, and the circumferential spacing between two adjacent longitudinal connecting bars is 1m.

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