Combined support system and method for prestressed cable truss and U-shaped steel in arched roadway

Abstract

The present invention discloses a combined support system and method for prestressed anchor cable trusses and U-shaped steel in arched roadways, including an arched roadway, a U-shaped steel support, and an anchor cable assembly connected to the U-shaped steel support; the anchor cable assembly includes an anchor cable member located in the rock mass, an anchor cable connector, and a locking device, the anchor cable connector is located inside the U-shaped steel support, and the anchor cable member is connected to the U-shaped steel support; the anchor cable member includes a middle anchor cable located at the top of the U-shaped steel support, a right anchor cable located on the right side of the middle anchor cable, and a left anchor cable located on the left side of the middle anchor cable, the left anchor cable and the right anchor cable are respectively connected to the middle anchor cable through the anchor cable connector, the middle anchor cable is connected to the top of the U-shaped steel support through the locking device, and cement mortar is injected into the inner cavity of the U-shaped steel. The present invention realizes the collaborative load-bearing support of the anchor cable truss in the arched roadway through the anchor cable connector and the perforated U-shaped steel support, enhancing the support strength.

Description

Technical Field

[0001] The present invention relates to the technical field of mine roadway support, and particularly to a combined support system and method of prestressed anchor cable truss and U-shaped steel for arched roadways. Background Art

[0002] In mine exploitation, ensuring safety is the prerequisite for production, especially the safety of underground roadways. As the passage for mining operations, roadway support is an essential and important project. The mining face must be supported in a timely manner according to the regulations of the operation procedures, and all supports must be firmly erected. In the support project, the support for the top of the roadway is particularly important. As the roadway is driven forward, the roadway support equipment and support methods that provide effective support for the roadway also need to be strengthened additionally. If timely support cannot be obtained, it is extremely easy to cause roof collapse and then trigger safety accidents. The anchor cable truss support technology has been widely applied in the rectangular roadways of coal mines. The key to this technology is to connect the anchor cables into one body by using special anchor cable connectors to achieve the collaborative load-bearing between the anchor cables.

[0003] Currently, the application of the anchor cable truss in arched roadways is mainly to form a combined support structure with U-shaped steel. The specific implementation method of the existing anchor cable truss and U-shaped steel support method is to connect and fix each anchor cable to the U-shaped steel to form an anchor cable and U-shaped steel truss system. However, the special anchor cable connectors commonly used in the anchor cable truss support technology are not used. In this method, since the U-shaped steel between the anchor cables is a rigid structure and there is no direct interaction between the anchor cables, the key collaborative load-bearing of the anchor cables in the anchor cable truss support technology is not achieved. In addition, the rock mass in the anchorage area cannot be in a multi-directional extrusion state, and the support effect is difficult to guarantee.

[0004] In the prior art (CN202544879U), a roadway support device applied to extremely fractured areas such as underground fracture zones and faults, areas where ground stress is extremely easy to concentrate and the service time is relatively long is disclosed. Its purpose is to provide a high-strength roadway support device that can provide a stable and good support effect and eliminate potential safety hazards caused by unstable roadway support. A high-strength roadway support device of the present utility model includes several rows of resin long anchor cable groups, U-shaped arch frames, channel steels and round logs. Each row of resin long anchor cable groups includes 3 resin long anchor cables, forming a resin long anchor cable combination with a mesh size of 12×2.0 meters. Three channel steels are used to connect between two adjacent rows of resin long anchor cable groups. The U-shaped arch frame is a yieldable metal arch support. One U-shaped arch frame is arranged at the outer end of each row of resin long anchor cable groups. A number of round logs are filled along the direction of the tie rod in the gap between the U-shaped arch frame and the roadway rock wall. The gaps between the U-shaped arch frame, the roadway rock wall and the round logs are filled with concrete.

[0005] The device is provided with several rows of resin long anchor cable groups, which are rigidly connected row by row through channel steel. Each row is provided with a U-shaped arch frame, and there is no connection between the U-shaped arch frame and the resin long anchor cable group, resulting in a lack of collaborative bearing between the resin long anchor cable and the U-shaped steel frame, and the inability to form a combined support. The two can only be used as independent individuals for support respectively, and the support strength cannot be superimposed, so the effect of enhancing support cannot be achieved. Moreover, there is no connection between the resin long anchor cables, and the rock mass in the anchorage area cannot be in a multi-directional extrusion state, making it difficult to ensure the support effect. Summary of the Invention

[0006] Aiming at the deficiencies of the above-mentioned prior art, the purpose of the present invention is to provide a combined support system for prestressed anchor cable truss and U-shaped steel in arched roadways.

[0007] In order to solve the technical problem that the collaborative bearing cannot be formed between the anchor cable truss and the U-shaped steel support, the present invention adopts the technical means of forming a combined support between the anchor cable truss and the U-shaped steel support through an anchor cable connector, so as to achieve the technical effect of the collaborative bearing of the anchor cable truss and the U-shaped steel support.

[0008] The present invention is realized through the following technical solutions.

[0009] A combined support system for prestressed anchor cable truss and U-shaped steel in arched roadways includes an arched roadway, a U-shaped steel support, and an anchor cable assembly connected to the U-shaped steel support. The arched roadway is provided with installation holes, the U-shaped steel support is adapted to the arched roadway, the anchor cable assembly includes an anchor cable member, an anchor cable connector, and a locking device. The anchor cable member is arranged in the installation holes, the anchor cable connector is located inside the U-shaped steel support, the anchor cable member is connected to the U-shaped steel support through the locking device. The anchor cable member includes a middle anchor cable at the top of the U-shaped steel support, a right anchor cable on the right side of the middle anchor cable, and a left anchor cable on the left side of the middle anchor cable. The left anchor cable and the right anchor cable are respectively connected to the middle anchor cable through the anchor cable connector, and the middle anchor cable is connected to the top of the U-shaped steel support through the locking device.

[0010] Preferably, the anchor cable connector is designed in an inverted trapezoid shape and is adapted to the cross-section of the U-shaped steel support. The anchor cable connector is provided with two horizontally transverse and parallel horizontal through holes and a vertical through hole in the vertical direction. The two horizontal through holes are respectively located on both sides of the vertical through hole, and the diameters of the horizontal through hole and the vertical through hole are the same and are adapted to the anchor cable member.

[0011] Preferably, the middle anchor cable passes through the vertical through hole and is connected to the U-shaped steel support through the locking device. The left anchor cable and the right anchor cable respectively pass through the two horizontal through holes, and the left anchor cable and the right anchor cable are respectively connected to the anchor cable connector through the locking device.

[0012] Preferably, the anchor cable assembly further includes an anchor rod, which is located on both sides of the arched roadway and is connected to the U-shaped steel support through a locking member.

[0013] Preferably, connection holes adapted to the anchor rods are provided on both sides of the U-shaped steel support. The anchor rods pass through the connection holes and are connected to the locking members, and the anchor rods and the U-shaped steel support are locked through the locking members.

[0014] Preferably, the U-shaped steel support is further provided with four grouting holes, which are respectively located between the left anchor cable and the middle anchor cable, between the middle anchor cable and the right anchor cable, and on both sides of the U-shaped steel support.

[0015] Preferably, a protective net is provided on the inner surface of the arched roadway, and the protective net is located between the arched roadway and the U-shaped steel support.

[0016] Preferably, a plurality of the anchor rods are symmetrically distributed on both sides of the U-shaped steel support, and the anchor rods are arranged at equal intervals.

[0017] Preferably, the locking device includes an anchor ring sleeved on the anchor cable member, a locking nut threadedly connected to the outer periphery of the anchor ring, and an elastic cushion plate, and the elastic cushion plate is located between the anchor ring and the U-shaped steel support.

[0018] A method for the combined support system of the prestressed anchor cable truss and the U-shaped steel in the arched roadway according to any one of the above, the specific steps are as follows:

[0019] Step 1: After the excavation of the arched roadway, knock on the sides and roof to check for loose rocks, clean up the floating stones, drill three installation holes at the top of the arched roadway, then drill anchor rod holes at both sides of the arched roadway, lay the protective net in the arched roadway, then install the middle anchor cable in the vertically upward installation hole, and then install the left anchor cable and the right anchor cable in the installation holes on both sides respectively. Pass the vertical through hole of the anchor cable connector through the connection end of the middle anchor cable, and at the same time pass the connection ends of the left anchor cable and the right anchor cable through the two horizontal through holes of the anchor cable connector respectively; then use the anchor cable tensioner to tighten the left anchor cable and the right anchor cable and fix them through the locking device.

[0020] Step 2: According to the design dimensions of the cross-section of the arched roadway and the design requirements of the inverted arch, prefabricate the U-shaped steel support in advance, and process the through holes for the anchor cable members and the connection holes for the anchor rods at the corresponding positions of the U-shaped steel support; secondly, open grouting holes at the positions between the left anchor cable and the middle anchor cable, between the middle anchor cable and the right anchor cable, and on both sides of the U-shaped steel support on the U-shaped steel support, then erect the U-shaped steel support, and the middle anchor cable at the crown position of the U-shaped steel support is tensioned by the anchor cable tensioner and fixed to the crown of the U-shaped steel support through the locking device; then install and fix the anchor rods on both sides.

[0021] Step 3: Inject cement mortar into the cavity between the U-shaped steel support and the arched roadway through the grouting holes at the crown and both sides of the U-shaped steel support. When grouting, the sequence of bottom-up and left-to-right is adopted.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows: The middle cable bolt, the left cable bolt and the right cable bolt achieve the collaborative bearing between the cable bolts through the cable bolt connector. At the same time, the middle cable bolt and the bolt are respectively connected to the U-shaped steel support through the locking device and the locking piece, so that a collaborative bearing and combined support system is formed between the cable bolt truss and the U-shaped steel support. The cable bolt truss makes the roof surrounding rock in a vertically and horizontally extruded state, and the pre-tightening force of the cable bolt can effectively control the settlement of the roof.

[0023] The cable bolt connector is designed in an inverted trapezoid shape and is adapted to the cross-section of the U-shaped steel support, ensuring the coordination of the support structure.

[0024] The U-shaped steel support increases the rigidity of the support structure, thereby improving the bearing capacity of the support structure. The post-grouting behind the U-shaped steel support makes the support structure in surface contact with the surrounding rock, with a large acting range and a good stress state of the loose and broken roof. At the same time, a protective net is arranged between the U-shaped steel support and the arched roadway to prevent the falling of the top gravel, achieving a double protection effect.

[0025] The bolt is locked on the U-shaped steel support to prevent the bolt from loosening and falling off due to the deformation of the surrounding rock. At the same time, the bolt also plays a role in fixing the U-shaped steel.

[0026] In summary, the support system effectively improves the stress distribution between the arched roadway and the surrounding rock. The cable bolt assembly and the bolt are not easy to fail, simple to operate, good in support effect and low in cost, ensuring the safety of the construction project. Description of the Drawings

[0027] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the following drawings are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0028] Figure 1 It is a cross-sectional view of the arched roadway of the present invention;

[0029] Figure 2 It is Figure 1 A partial enlarged view of part A;

[0030] Figure 3 It is a structural schematic diagram of the cable bolt assembly and part of the U-shaped steel support of the present invention;

[0031] Figure 4 This is the front view of the anchor cable component and part of the U-shaped steel support of the present invention;

[0032] Figure 5 This is the left view of the anchor cable component and part of the U-shaped steel support of the present invention;

[0033] Figure 6 This is the structural schematic diagram of the lock of the present invention;

[0034] Figure 7 This is the cross-sectional view of the lock of the present invention;

[0035] Figure 8 This is the structural schematic diagram of the anchor cable connector of the present invention;

[0036] In the figure: 1-arch roadway; 2-U-shaped steel support; 21-grouting hole; 3-anchor cable component; 31-anchor cable member; 311-middle anchor cable; 312-right anchor cable; 313-left anchor cable; 32-anchor cable connector; 321-horizontal through hole; 322-vertical through hole; 33-lock; 331-anchor ring; 332-lock nut; 333-elastic backing plate; 34-anchor bolt; 341-locking member; 4-protective net; 5-cement mortar; Specific embodiments

[0037] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the scope protected by the present invention.

[0038] The present invention will be further described in detail below through specific embodiments in conjunction with the accompanying drawings.

[0039] Embodiment 1

[0040] A prestressed anchor cable truss and U-shaped steel combined support system for an arch roadway, comprising an arch roadway 1, a U-shaped steel support 2, and an anchor cable component 3 connected to the U-shaped steel support 2. Installation holes are pre-drilled at the top of the arch roadway 1, and the installation holes are adapted to the anchor cable component 3; the U-shaped steel support 2 includes vertical parts on the left and right sides and an arch part at the top. The vertical parts on both sides and the top arch part are integrally formed without joints, and have good bearing capacity. And the U-shaped steel support 2 is in contact with the arch roadway 1; the open side of the U-shaped steel support 2 faces the surrounding rock of the arch roadway 1, that is, a cavity is formed between the U-shaped steel support 2 and the arch roadway 1, and the U-shaped steel support 2 is also provided with through holes corresponding to the installation holes one by one.

[0041] The anchor cable assembly 3 includes a cable member 31, a cable connector 32, and a locking device 33. The cable member 31 is disposed in the installation hole and fixedly connected to the arched roadway 1, and the connecting end of the cable member 31 is located within the arched roadway 1. The cable connector 32 is located within the cavity of the U-shaped steel support 2 and at the top of the U-shaped steel support 2. The cable member 31 is connected to the U-shaped steel support 2 through the locking device 33. The cable member 31 includes a middle cable 311 at the top of the U-shaped steel support 2, a right cable 312 on the right side of the middle cable 311, and a left cable 313 on the left side of the middle cable 311. The left cable 313, the right cable 312, and the middle cable 311 have the same diameter. The left cable 313 and the right cable 312 are respectively connected to the middle cable 311 through the cable connector 32, and the middle cable 311 is connected to the top of the U-shaped steel support 2 through the locking device 33.

[0042] The cable connector 32 is designed in an inverted trapezoid shape and is adapted to the cross-section of the U-shaped steel support 2. The cable connector 32 is provided with two horizontally transverse and parallel horizontal through-holes 321 and a vertically oriented vertical through-hole 322. That is, the horizontal through-holes 321 are parallel to the horizontal direction of the cross-section of the arched roadway 1, and the vertical through-hole 322 is parallel to the vertical direction of the cross-section of the arched roadway 1. The two horizontal through-holes 321 are respectively located on both sides of the vertical through-hole 322. The horizontal through-holes 321 and the vertical through-hole 322 have the same aperture and are adapted to the left cable 313, the right cable 312, and the middle cable 311.

[0043] The connecting end of the middle cable 311 passes through the vertical through-hole 322 of the cable connector 32 and the through-hole on the U-shaped steel support 2 and is locked to the U-shaped steel support 2 through the locking device 33. The connecting end of the left cable 313 passes through one of the horizontal through-holes 321 of the cable connector 32 from the left side and is connected to the cable connector 32 through the locking device 33. The right cable 312 passes through the other horizontal through-hole 321 of the cable connector 32 from the right side and is connected to the cable connector 32 through the locking device 33.

[0044] The anchor cable assembly 3 further includes an anchor bolt 34. The anchor bolt 34 is located inside the sidewalls on both sides of the arched roadway 1, and the connecting end of the anchor bolt 34 is also located within the arched roadway 1. Connection holes corresponding to the anchor bolt 34 are provided on both sides of the U-shaped steel support 2. The end of the anchor bolt 34 passes through the connection hole and is connected to the locking member 341, and the anchor bolt 34 is locked to the U-shaped steel support 2 through the locking member 341. There are several anchor bolts 34, symmetrically distributed on both sides of the U-shaped steel support 2, and the anchor bolts 34 on one side are arranged at equal intervals, so that the entire support system is evenly stressed.

[0045] The U-shaped steel support 2 is also provided with four grouting holes 21, which are respectively located between the left anchor cable 313 and the middle anchor cable 311, between the middle anchor cable 311 and the right anchor cable 312, and on both sides of the U-shaped steel support 2. The grouting holes 21 are used to inject cement mortar 5 into the cavity, so that the U-shaped steel support 2 forms a surface contact with the surrounding rock, with a large action range and a good stress state of the loose and broken roof.

[0046] A protective net 4 is arranged on the inner surface of the arched roadway 1. The protective net 4 is located between the arched roadway 1 and the U-shaped steel support 2; the protective net 4 is a wire rope net, which is used to protect the arched roadway 1 to prevent crushed stones from falling into the arched roadway 1.

[0047] The locking device 33 includes an anchor ring 331 sleeved on the anchor cable member 31, a locking nut 332 threadedly connected to the outer periphery of the anchor ring 331, and an elastic cushion plate 333; the elastic cushion plate 333 is located between the anchor ring 331 and the U-shaped steel support 2. The anchor ring 331 is provided with a through hole for accommodating the anchor cable member 31. One end of the anchor ring 331 is tapered and provided with a through groove at the tapered end, and the other end is provided with an external thread; the locking nut 332 is provided with a through hole for accommodating the anchor ring 331. One end of the through hole of the locking nut 332 is provided with an internal thread adapted to the anchor ring 331, and the other end is a tapered hole adapted to the tapered end of the anchor ring 331. By the threaded cooperation of the locking nut 332 and the anchor ring 331, the purpose of locking the anchor cable member 31 is achieved.

[0048] The working principle of the combined support system of the prestressed anchor cable truss and the U-shaped steel support for the arched roadway provided by the present invention will be described below:

[0049] After the excavation of the arched roadway 1, knock on the sides and check for loose stones, clean the floating stones, drill three installation holes at the top of the arched roadway 1, and the three installation holes are fan-shapedly distributed, one of which is vertically upward, and the other two are located on both sides of it. Then drill several bolt holes on both side walls of the arched roadway 1. First, lay the protective net 4 in the arched roadway 1, and then install the middle anchor cable 311 in the vertically upward installation hole and grout it for fixation; then install the left anchor cable 313 and the right anchor cable 312 in the installation holes on both sides respectively and grout them for fixation. Pass the vertical through hole of the anchor cable connector 32 through the connection end of the middle anchor cable 311, and at the same time pass the connection ends of the left anchor cable 313 and the right anchor cable 312 through the two horizontal through holes 321 of the anchor cable connector 32 respectively; then use the anchor cable tensioner to tighten the left anchor cable 313 and the right anchor cable 312 and fix them through the locking device 33. After the installation of the top part of the arched roadway 1 is completed, install the bolts 34 in the bolt holes on both sides of the arched roadway 1 and grout them for fixation.

[0050] Arrange U-shaped steel supports 2 according to the inner surface of the arched roadway 1. The shape of the U-shaped steel support 2 is matched with the inner surface of the arched roadway 1. According to the design dimensions of the cross-section of the arched roadway 1 and the design requirements of the invert, prefabricate the U-shaped steel support 2 in advance, and process through holes for cable bolts 31 and connection holes for anchor bolts 34 at corresponding positions of the U-shaped steel support 2; secondly, drill grouting holes 21 at positions on the U-shaped steel support 2 between the left cable bolt 313 and the middle cable bolt 311, between the middle cable bolt 311 and the right cable bolt 312, and on both sides of the U-shaped steel support 2.

[0051] Then erect the U-shaped steel support 2. After the erection of the U-shaped steel support 2 is completed, the purpose of fixing the protective net 4 is achieved. The middle cable bolt 311 at the crown position of the U-shaped steel support 2 is tensioned by a cable bolt tensioner and fixed to the crown of the U-shaped steel support 2 through a locking device 33; then install and fix the anchor bolts 34 on both sides, and the fixation of the entire U-shaped steel support 2 is completed.

[0052] Inject cement mortar 5 into the cavity between the U-shaped steel support 2 and the arched roadway 1 through the grouting holes 21 at the crown and both sides of the U-shaped steel support 2. When grouting, use the sequence from bottom to top and from left to right. After the cement mortar is completely solidified, the erection of a set of support systems is completed.

[0053] Finally, according to the actual length of the arched roadway 1, erect several sets of support systems, and the spacing between adjacent support systems is the same.

[0054] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the technical solutions of the embodiments of the present invention.

Claims

1. An arched roadway prestressed anchor cable truss and U-shaped steel combined support system, comprising an arched roadway (1), a U-shaped steel support (2), and an anchor cable assembly (3) connected to the U-shaped steel support (2), characterized in that, The arched roadway (1) is provided with installation holes. The U-shaped steel support (2) is adapted to the arched roadway (1). The anchor cable assembly (3) includes a cable anchor (31), a cable anchor connector (32), and a locking device (33). The cable anchor (31) is disposed in the installation hole. The cable anchor connector (32) is located within the U-shaped steel support (2). The cable anchor (31) is connected to the U-shaped steel support (2) through the locking device (33). The cable anchor (31) includes a middle cable anchor (311) at the top of the U-shaped steel support (2), a right cable anchor (312) on the right side of the middle cable anchor (311), and a left cable anchor (313) on the left side of the middle cable anchor (311). The left cable anchor (313) and the right cable anchor (312) are respectively connected to the middle cable anchor (311) through the cable anchor connector (32). The left cable anchor (313), the right cable anchor (312), and the middle cable anchor (311) have the same diameter. The cable anchor connector (32) is designed in an inverted trapezoid shape and is adapted to the cross-section of the U-shaped steel support (2). The cable anchor connector (32) is provided with two horizontally transverse and parallel horizontal through-holes (321) and one vertically oriented vertical through-hole (322). The two horizontal through-holes (321) are respectively located on both sides of the vertical through-hole (322). The horizontal through-holes (321) and the vertical through-hole (322) have the same aperture and are adapted to the cable anchor (31). The middle cable anchor (311) passes through the vertical through-hole (322) and is connected to the U-shaped steel support (2) through the locking device (33). The left cable anchor (313) and the right cable anchor (312) respectively pass through the two horizontal through-holes (321), and the left cable anchor (313) and the right cable anchor (312) are respectively connected to the cable anchor connector (32) through the locking device (33).

2. The arched roadway prestressed anchor cable truss and U-shaped steel combined support system according to claim 1, characterized in that, The anchor cable assembly (3) further includes a plurality of bolts (34). The bolts (34) are located on both sides of the arched roadway (1) and are connected to the U-shaped steel support (2) through locking members (341).

3. The arched roadway prestressed anchor cable truss and U-shaped steel combined support system according to claim 2, characterized in that, Connection holes adapted to the bolts (34) are provided on both sides of the U-shaped steel support (2). The bolts (34) pass through the connection holes and are connected to the locking members (341), and the bolts (34) are locked to the U-shaped steel support (2) through the locking members (341).

4. The arched roadway prestressed anchor cable truss and U-shaped steel combined support system according to claim 1, characterized in that, The U-shaped steel support (2) is further provided with four grouting holes (21), which are respectively located between the left cable anchor (313) and the middle cable anchor (311), between the middle cable anchor (311) and the right cable anchor (312), and on both sides of the U-shaped steel support (2).

5. The arched roadway prestressed anchor cable truss and U-shaped steel combined support system according to claim 1, characterized in that, A protective net (4) is provided on the inner surface of the arched roadway (1). The protective net (4) is located between the arched roadway (1) and the U-shaped steel support (2).

6. The arched roadway prestressed anchor cable truss and U-shaped steel combined support system according to claim 2, characterized in that, A plurality of the bolts (34) are symmetrically distributed on both sides of the U-shaped steel support (2), and the bolts (34) are arranged at equal intervals.

7. The arched roadway prestressed anchor cable truss and U-shaped steel combined support system according to claim 1, characterized in that, The locking device (33) includes an anchor ring (331) sleeved on the cable anchor member (31), a locking nut (332) threadedly connected to the outer periphery of the anchor ring (331), and an elastic backing plate (333). The elastic backing plate (333) is located between the anchor ring (331) and the U-shaped steel support (2).

8. A method based on the arched roadway prestressed anchor cable truss and U-shaped steel combined support system according to any one of claims 1-7, the specific steps are as follows: Step 1: After the excavation of the arched roadway (1), knock on the roof and sides to check for loose rocks, clean the loose rocks, drill three installation holes at the top of the arched roadway (1), then drill anchor holes at both sides of the arched roadway (1), lay the protective net (4) inside the arched roadway (1), then install the middle anchor cable (311) into the vertically upward installation hole, and then install the left anchor cable (313) and the right anchor cable (312) into the installation holes on both sides respectively. Pass the vertical through hole of the anchor cable connector (32) through the connection end of the middle anchor cable (311), and at the same time pass the connection ends of the left anchor cable (313) and the right anchor cable (312) through the two horizontal through holes (321) of the anchor cable connector (32); then use an anchor cable tensioner to tighten the left anchor cable (313) and the right anchor cable (312) and fix them with locks (33). Step 2: According to the sectional design dimensions of the arched roadway (1) and the design requirements of the inverted arch, prefabricate the U-shaped steel support (2) in advance, and process through holes for the cable anchor parts (31) and connection holes for the anchor bolts (34) at corresponding positions of the U-shaped steel support (2); secondly, open grouting holes (21) at positions between the left cable anchor (313) and the middle cable anchor (311), between the middle cable anchor (311) and the right cable anchor (312), and on both sides of the U-shaped steel support (2) on the U-shaped steel support (2), then erect the U-shaped steel support (2), and fix the middle cable anchor (311) at the crown of the U-shaped steel support (2) to the crown of the U-shaped steel support (2) through a cable anchor tensioner and a locking device (33) after tensioning; then install and fix the anchor bolts (34) on both sides; Step 3: Inject cement mortar (5) into the cavity between the U-shaped steel support (2) and the arched roadway (1) through the grouting holes (21) at the crown and both sides of the U-shaped steel support (2), and adopt the sequence from bottom to top and from left to right during grouting.

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