Roadway bolting-grouting integrated support system for broken surrounding rock

Abstract

The invention discloses a bolting and grouting integrated supporting system for a broken surrounding rock roadway, and belongs to the field of roadway supporting. A bolting and grouting integrated supporting system for a broken surrounding rock roadway comprises a main supporting area distributed in the roadway, and four third mounting holes are formed in the upper end of the interior of an auxiliary supporting area in a surrounding mode. And a monitoring rod consisting of an anchor cable, a broadband speed sensor, a three-component accelerometer, a limiting ring, a protective cover and a third feeding hole is arranged in the third mounting hole. The surrounding rock roadway bolting-grouting integrated supporting system solves the problems that in the supporting process of an existing surrounding rock roadway bolting-grouting integrated supporting system, the connecting relation between adjacent hollow grouting anchor rods and long anchor cables is poor, and the whole roadway cannot be supported in a unified mode. The first concrete filled in the main supporting area improves the integrity of the supporting position.

Description

Technical Field

[0001] This invention relates to the field of roadway support, specifically to an integrated anchoring and injection support system for roadways with fractured surrounding rock. Background Technology

[0002] The integrated anchor-grouting support structure for roadways in fractured surrounding rock is a support technology designed for such roadways. It aims to improve the stability and safety of the roadway and enhance the integrity of the surrounding rock by combining anchor bolts with grouting. Grouting technology injects grout into the fissures and pores of the surrounding rock; after solidification, the grout fills the fissures, further improving the strength and deformation resistance of the surrounding rock. This integrated anchor-grouting support structure not only effectively controls the deformation and damage of the surrounding rock but also improves the stress distribution of the roadway, reduces the amount of support material used, and increases construction efficiency. This technology is widely used in mining, tunneling, and other engineering projects, and is particularly suitable for roadway support in complex geological conditions and fractured surrounding rock, offering significant economic and safety benefits.

[0003] Chinese Patent Publication No. CN206681751U discloses an integrated anchoring and grouting support system for roadways in fractured surrounding rock. The system includes a first concrete layer on the surface of the fractured zone of the roadway's surrounding rock, a steel mesh outside the first concrete layer, a long anchor cable extending into the roadway's surrounding rock with its anchoring end located in the elastic zone, and a hollow grouting anchor rod with its anchoring end located in the plastic zone. This support system effectively coordinates the deformation of deep and shallow rock masses, achieving a unified load-bearing structure for both deep and shallow surrounding rock. This significantly improves the stability of roadways in fractured surrounding rock, reduces the frequency and cost of underground roadway maintenance, and yields substantial social and economic benefits.

[0004] In the aforementioned patented integrated rock grouting support system for roadways, the connection between adjacent hollow grouting anchors and long anchor cables is poor during the support process, making it impossible to provide unified support for the entire roadway. Furthermore, there is no independent monitoring structure after support, making it impossible to continuously monitor the support position. Summary of the Invention

[0005] The purpose of this invention is to provide an integrated anchoring and injection support system for roadways with fractured surrounding rock. By alternately distributing main support zones and secondary support zones to support the locations to be supported in the roadway, the first concrete filling inside the main support zone improves the integrity of the support location. Meanwhile, broadband velocity sensors and three-component accelerometers monitor the locations at different depths to prevent collapse caused by rock mass fracturing. Additional reinforcement can be carried out before collapse, thus solving the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: an integrated anchoring and injection support system for roadways in fractured surrounding rock, comprising a main support zone located within the roadway, a secondary support zone between two adjacent main support zones, and four third mounting holes arranged around the upper end of the secondary support zone. Each third mounting hole contains a monitoring rod consisting of an anchor cable, a broadband velocity sensor, a three-component accelerometer, a limiting ring, a protective cover, and a third feed inlet. The main support zone comprises a groove, anchor cables, self-drilling anchor rods, reinforcing bars, and a grinding wheel. The groove is recessed within the roadway, with the anchor cables located on both sides and the lower end of the groove, and the self-drilling anchor rods located around the upper end of the groove. The main and secondary support zones alternately support the roadway. During the support process, the broadband velocity sensor and the three-component accelerometer monitor rock fracture. Simultaneous monitoring during support allows for timely replenishment of the support structure.

[0007] Preferably, a pair of limiting rings are arranged laterally, with the broadband velocity sensor located on one side of one of the limiting rings and the three-component accelerometer located on the other side of the other limiting ring. During the support process, the broadband velocity sensor and the three-component accelerometer are located on both sides of the pair of limiting rings, and the broadband velocity sensor and the three-component accelerometer are restricted by the pair of limiting rings. The restriction can prevent cement from contacting the broadband velocity sensor and the three-component accelerometer.

[0008] Preferably, the anchor cable has a pre-drilled first mounting hole on its exterior, and the first mounting hole is embedded inside the tunnel. The inner wall of the first mounting hole is surrounded by a hole-encasing wall made of cement. Covering the hole with the hole-encasing wall can prevent the first mounting hole from collapsing before filling with cement.

[0009] Preferably, the reinforcing bars are distributed around the inside of the groove, and the mold completely covers and wraps the groove. The upper end of the mold is provided with a first inlet. A first concrete is provided between the mold and the groove. The reinforcing bars, together with the subsequently filled first concrete, can improve the bearing capacity of the entire rock tunnel anchor-injection integrated support system.

[0010] Preferably, a temporary support sheet pre-sprayed onto the surface of the groove is provided between the first concrete and the groove. The temporary support sheet is sprayed cement. Before the first concrete is filled, the temporary support sheet formed by cement covers the surface of the groove. The sprayed temporary support sheet helps the subsequent solidification and support of the first concrete.

[0011] Preferably, the anchor cable is located at the center of the third mounting hole, and a pair of limiting rings are welded to the outside of the anchor cable. The anchor cable has a pre-drilled through hole, through which cement can be quickly filled into the filling cavity, so that the cement can fix the monitoring rod and prevent the cement from contacting the broadband velocity sensor and the three-component accelerometer.

[0012] Preferably, the protective cover is located between the broadband velocity sensor and the three-component accelerometer. A third inlet is provided around the anchor cable between a pair of limiting rings, and the third inlet passes through the anchor cable and extends to the through hole inside the anchor cable. A filling cavity is provided between the pair of limiting rings. The reserved third inlet facilitates the filling of cement and also facilitates the fixing of the monitoring rod with cement at the filling cavity position.

[0013] Preferably, the anchor cable consists of a support rod, a metal rod, and a hoop. The support rod is located in the middle of the first mounting hole. Four metal rods are evenly distributed around the support rod. The hoop is wrapped around the outer wall of the metal rod and the support rod. The support rod facilitates the support of the metal rod, improves the stability of the metal rod, and facilitates the overall erection of the anchor cable and the support of the roadway.

[0014] Preferably, the support rod has a second inlet through which cement is fed to fill the space between the anchor cable and the hole wall, thereby increasing the contact area between the cement and the anchor cable and the hole wall.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0016] 1. This invention covers the outer wall of the subsequent support location by sequentially spraying temporary support plates and hole-encasing walls at the main support area, preventing collapse and deformation when the first concrete is filled with cement. Secondly, through the spraying of temporary support plates and hole-encasing walls, the first concrete can form a unified structure with the temporary support plates and hole-encasing walls during subsequent filling, uniformly supporting and connecting the anchor cables and self-drilling anchors. This directly improves the integrity of the entire integrated anchor-injection support system for fractured surrounding rock roadways, and enhances the load-bearing capacity and stability of the integrated anchor-injection support system for fractured surrounding rock roadways.

[0017] 2. This invention provides an additional secondary support zone between two adjacent main support zones to assist the entire integrated anchor-grouting support system for fractured surrounding rock tunnels. Firstly, anchor cables are filled within the secondary support zone for auxiliary support. Secondly, the anchor cables, carrying a broadband velocity sensor and a three-component accelerometer, are placed inside a second mounting hole. While providing auxiliary support, the broadband velocity sensor and three-component accelerometer monitor the surrounding area of ​​the support location. This allows for additional support at rock fracture sites, preventing subsequent collapse. Furthermore, the connection and data transmission between the broadband velocity sensor and the three-component accelerometer are crucial. The installation position of the speed meter and the restriction of the position between the broadband speed sensor and the three-component accelerometer by a pair of limiting rings ensure that the cement being transmitted will not come into contact with the broadband speed sensor and the three-component accelerometer. In addition, before transmitting cement, a cable for transmitting data from the broadband speed sensor and the three-component accelerometer is pre-installed between the pair of limiting rings. The cable is transmitted uniformly from the protective cover position and extends from the monitoring pole mounting position, which facilitates unified connection with external monitoring equipment, facilitates data reception and analysis, and prevents cement from contacting and covering the broadband speed sensor and the three-component accelerometer, thereby improving the monitoring accuracy of the broadband speed sensor and the three-component accelerometer.

[0018] 3. When the broadband velocity sensor and the three-component accelerometer are installed and pre-fixed to the surface of the anchor cable, the broadband velocity sensor is close to the third mounting hole, while the three-component accelerometer is recessed inside the third mounting hole. By measuring the position, data at different depths can be monitored simultaneously, making the monitored rock mass fracture data more accurate and avoiding misjudgment by external personnel. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall external structure of the present invention;

[0020] Figure 2 This is an exploded view of the internal structure of the main support area of ​​the present invention;

[0021] Figure 3 This is an exploded view of the anchor cable position relationship of the present invention;

[0022] Figure 4 This is an exploded view of the second concrete positional relationship according to the present invention;

[0023] Figure 5 This is a cross-sectional view of the internal structure of the main support area of ​​the present invention;

[0024] Figure 6 For the present invention Figure 5 Enlarged view of a portion of region A in the middle;

[0025] Figure 7 For the present invention Figure 5 Enlarged view of a portion of region B in the middle;

[0026] Figure 8 This is a cross-sectional view of the internal structure of the secondary support area of ​​the present invention;

[0027] Figure 9 For the present invention Figure 8 Enlarged view of a portion of region C.

[0028] In the diagram: 1. Tunnel; 2. Main support zone; 3. Secondary support zone; 4. Abrasive tool; 5. Groove; 6. Anchor cable; 7. Self-drilling anchor bolt; 8. Hole wall; 9. First mounting hole; 10. Second mounting hole; 11. Temporary support plate; 12. Reinforcing bar; 13. First concrete; 15. First feed inlet; 16. Support rod; 17. Metal rod; 18. Hoop ring; 19. Second feed inlet; 20. Monitoring rod; 21. Anchor cable; 22. Wideband velocity sensor; 23. Three-component accelerometer; 24. Restriction ring; 25. Filling cavity; 26. Third feed inlet; 27. Second concrete; 28. Protective cover; 29. ​​Third mounting hole. Detailed Implementation

[0029] The present invention will be further described below with reference to specific embodiments.

[0030] Example 1

[0031] like Figure 1 As shown in the figure, an integrated anchoring and injection support system for roadways with fractured surrounding rock in this embodiment includes a main support zone 2 and a secondary support zone 3. The main support zone 2 and the secondary support zone 3 are alternately distributed laterally on the inner wall of the roadway 1. The main support zone 2 mainly supports the roadway 1, while the secondary support zone 3 provides auxiliary support and supports the interior of the roadway 1. The system monitors rock mass fracture. After rock mass fracture is detected, the support of the main support zone 2 area can be replenished in time to prevent the roadway from collapsing.

[0032] Among them, such as Figure 2 As shown, the main support area 2 is composed of groove 5, anchor cable 6, self-drilling anchor 7, steel bar 12 and abrasive 4. The groove 5 is recessed inside the tunnel 1. The recessed groove 5 makes it easy for the self-drilling anchor 7 and anchor cable 6 to be installed later to be stored inside, avoiding one end of the self-drilling anchor 7 and anchor cable 6 from continuously protruding from the inner wall of the tunnel 1.

[0033] In addition, such as Figure 2 , Figure 5 and Figure 7As shown, the anchor cable 6 is located on both sides and the lower end of the groove 5, and the self-drilling anchor rod 7 is located around the upper end of the groove 5. The combination of the anchor cable 6 and the self-drilling anchor rod 7 can provide subsequent support. In order to facilitate the delivery of cement and the fixing of the self-drilling anchor rod 7 and the anchor cable 6, the self-drilling anchor rod 7 is provided with a second mounting hole 10 on its outside. The second mounting hole 10 is formed after the self-drilling anchor rod 7 rotates and extends into the roadway 1. The self-drilling anchor rod 7 is hollow inside. While rotating and embedding into the second mounting hole 10, cement is filled into the second mounting hole 10. The cement delivery is completed when the self-drilling anchor rod 7 is fully embedded into the second mounting hole 10.

[0034] like Figure 2 and Figure 6 As shown, the anchor cable 6 has a pre-drilled first installation hole 9 on its outside, and the first installation hole 9 is embedded in the tunnel 1. The inner wall of the first installation hole 9 is surrounded by a hole-encasing wall 8 made of cement. The hole-encasing wall 8 wraps and restricts the first installation hole 9 to prevent the collapse of the first installation hole 9 when the anchor cable 6 is not inserted.

[0035] To improve the uniformity of the self-drilling anchor bolt 7 and the anchor cable 6, so that the self-drilling anchor bolt 7 and the anchor cable 6 are integrated structures when supported, thereby improving the load-bearing capacity, the reinforcing bars 12 are distributed around the inside of the groove 5, and the abrasive 4 is set outside the distributed reinforcing bars 12, and the abrasive 4 completely covers and wraps the groove 5. The wrapping of the abrasive 4 facilitates subsequent filling.

[0036] Among them, such as Figure 5 and Figure 7 As shown, a first feed port 15 is provided through the upper end of the mold 4. The filler material can be injected into the space between the mold 4 and the groove 5 through the first feed port 15. A first concrete 13 is provided between the mold 4 and the groove 5. After the first concrete 13 solidifies, it is supported by the steel bar 12, which can improve the integrity of the anchor cable 6 and the self-drilling anchor 7 and improve the bearing capacity of the main support area 2.

[0037] In addition, a temporary support plate 11 pre-sprayed on the surface of the groove 5 is provided between the first concrete 13 and the groove 5. The temporary support plate 11 is sprayed cement. After the temporary support plate 11 is sprayed and solidified, it can provide support before the subsequent first concrete 13 is filled and solidified, thereby improving the stability of the integrated anchoring and injection support system for the broken surrounding rock roadway.

[0038] like Figure 1 , Figure 4 and Figure 8As shown, four third mounting holes 29 are arranged around the upper part of the secondary support zone 3. The third mounting holes 29 are formed by drilling holes in the secondary support zone 3 of the roadway 1 in advance. A monitoring rod 20 is installed inside the third mounting hole 29. The monitoring rod 20 consists of an anchor cable 21, a broadband velocity sensor 22, a three-component accelerometer 23, a limiting ring 24, a protective cover 28, and a third feed port 26. The anchor cable 21 has a through hole reserved inside. The anchor cable 21 is located at the center of the third mounting hole 29. The anchor cable 21 at the center can support the three-component accelerometer 23 and the limiting ring 24 while providing auxiliary support for the roadway 1. A pair of limiting rings 24 are arranged laterally and welded to the outside of the anchor cable 21.

[0039] The wideband velocity sensor 22 is located on one side of one of the limiting rings 24, and the three-component accelerometer 23 is located on the other side of the other limiting ring 24. The frequency range of the three-component accelerometer 23 is 1Hz to 5kHz, and the sensitivity of the three-component accelerometer 23 is 5V / g. The frequency range of the wideband velocity sensor 22 is 0.1Hz to 1kHz, and the dynamic range of the wideband velocity sensor 22 is greater than 140dB. The three-component accelerometer 23 monitors deep rock fractures, while the wideband velocity sensor 22 monitors shallow fractures. The three-component accelerometer 23 has excellent low-frequency response and strong anti-interference ability, while the wideband velocity sensor 22 has both low-frequency and high-frequency signal capture capabilities. The two are combined and installed at the third mounting hole 29 to monitor the supported roadway.

[0040] In addition, the protective cover 28 is located between the broadband velocity sensor 22 and the three-component accelerometer 23. The reserved protective cover 28 allows the broadband velocity sensor 22 and the three-component accelerometer 23 to be connected to the outside via cables, which is highly stable and avoids the impact of cement on the monitoring effect.

[0041] To facilitate the support of the monitoring rod 20, such as Figure 9 As shown, a third inlet 26 is provided around the anchor cable 21 between a pair of limiting rings 24, and the third inlet 26 passes through the anchor cable 21 and extends to the through hole inside the anchor cable 21. After the anchor cable 21 is inserted into the third mounting hole 29, cement can be directly fed into the anchor cable 21. A filling cavity 25 is provided between the pair of limiting rings 24. The cement transmitted to the anchor cable 21 will pass through the third inlet 26 and fill the filling cavity 25. The cement filled into the filling cavity 25 will contact the outer wall of the anchor cable 21 and the inner wall of the third mounting hole 29. The cement solidifies to form a second concrete 27. The connection of the second concrete 27 allows the three-component accelerometer 23 and the broadband velocity sensor 22 to be accurately located inside the sub-support area 3 and monitor the sub-support area 3.

[0042] To facilitate support inside the first mounting hole 9, such as Figure 3 , Figure 5 and Figure 6 As shown, the anchor cable 6 consists of a support rod 16, a metal rod 17, and a hoop 18. The support rod 16 is located in the middle of the first mounting hole 9. Four metal rods 17 are evenly distributed around the support rod 16. The hoop 18 is wrapped around the outer wall of the metal rod 17 and the support rod 16. The hoop 18 can fix the connection between the metal rod 17 and the support rod 16 when no cement is filled, which facilitates the installation of the anchor cable 6.

[0043] 2 were implemented

[0044] To facilitate the filling of cement around the anchor cable 6 and between the hole wall 8, a second inlet 19 is provided through the inside of the support rod 16. When filling cement into the hole wall 8, the cement flows in from the second inlet 19 and eventually flows into the required filling and fixing position. The cement solidification inside the second inlet 19 and between the anchor cable 6 and the hole wall 8, together with the hole wall 8, the temporary support plate 11 and the first concrete 13, can improve the stability of the anchor cable 6 and the self-drilling anchor rod 7 and improve the load-bearing capacity of the integrated anchor and injection support system.

[0045] 3 were implemented

[0046] To improve the stability of the integrated anchor-grouting support in the fractured surrounding rock tunnel, concrete was poured into both sides at the second inlet 19 inside the anchor cable 6, around the self-drilling anchor 7, and in the hollow part of the anchor cable 21. The cement-water ratio of the two concretes was 1:0.5 and 1:0.7, respectively. The grouting pressure during the second concrete filling needed to reach 1.5 to 2.0 MPa.

[0047] Working principle: When using the integrated roadway anchoring and grouting support system to support the roadway, a recessed groove 5 is pre-excavated in the main support area 2. Holes are drilled on both sides and the lower end of the groove 5 to form the first installation hole 9. The interior of the first installation hole 9 is pre-filled with cement. The cement is then re-drilled to form a hole wall 8. The anchor cable 6 is inserted into the center of the hole wall 8, and cement is filled around the hole wall 8 and the anchor cable 6. The self-drilling anchor 7 is actively rotated and embedded into the upper end of the groove 5 to form the second installation hole 10. While rotating and embedding, cement is filled into the self-drilling anchor 7, so that the cement filling is completed at the same time as the self-drilling anchor 7 is embedded. Cement is sprayed on the outside of the groove 5 to form a temporary support plate 11. The main support zone 2 is evenly distributed with steel bars 12. A mold 4 is laid on the outside of the steel bars 12 and at the top of the groove 5. Cement is filled into the mold 4 through the first feed port 15 at the top of the mold 4 and the cement is allowed to solidify. A third installation hole 29 is pre-drilled at the top of the secondary support zone 3 and a monitoring rod 20 is inserted into it. A three-component accelerometer 23 and a broadband velocity sensor 22 monitor the rock fracture at the deep end and near end, respectively. The through hole in the anchor cable 21 is filled and the cement flows out from the third feed port 26 and finally fills the filling cavity 25. The cement is allowed to solidify and form the second concrete 27. The main support zone 2 and the secondary support zone 3 are alternately distributed in the support position inside the roadway 1 to achieve integrated anchoring and injection support for the broken surrounding rock roadway.

[0048] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0049] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention.

Claims

1. An integrated anchoring and injection support system for roadways with fractured surrounding rock, comprising a main support zone (2) located within the roadway (1), characterized in that, A secondary support zone (3) is provided between two adjacent main support zones (2). The upper end of the secondary support zone (3) is surrounded by four third mounting holes (29). The third mounting holes (29) are equipped with a monitoring rod (20) consisting of an anchor cable (21), a broadband velocity sensor (22), a three-component accelerometer (23), a limiting ring (24), a protective cover (28), and a third feed inlet (26). The main support zone (2) is composed of a groove (5), an anchor cable (6), a self-drilling anchor bolt (7), a steel bar (12), and a grinding wheel (4). The groove (5) is recessed around the inside of the roadway (1). The anchor cable (6) is located on both sides and the lower end of the groove (5). The self-drilling anchor bolt (7) is located around the upper end of the groove (5).

2. The integrated anchoring and grouting support system for roadways with fractured surrounding rock according to claim 1, characterized in that, A pair of limiting rings (24) are arranged laterally, with the broadband velocity sensor (22) located on one side of one of the limiting rings (24) and the three-component accelerometer (23) located on the other side of the other limiting ring (24).

3. The integrated anchoring and grouting support system for roadways with fractured surrounding rock according to claim 1, characterized in that, The anchor cable (6) has a pre-drilled first mounting hole (9) on its outside, and the first mounting hole (9) is embedded inside the tunnel (1). The inner wall of the first mounting hole (9) is surrounded by a hole wall (8) solidified by cement.

4. The integrated anchoring and grouting support system for roadways with fractured surrounding rock according to claim 1, characterized in that, The reinforcing bars (12) are distributed around the inside of the groove (5), and the mold (4) completely covers and wraps the groove (5). The upper end of the inside of the mold (4) is provided with a first inlet (15), and a first concrete (13) is provided between the mold (4) and the groove (5).

5. The integrated anchoring and grouting support system for roadways with fractured surrounding rock according to claim 4, characterized in that, A temporary support plate (11) pre-sprayed on the surface of the groove (5) is provided between the first concrete (13) and the groove (5). The temporary support plate (11) is sprayed cement.

6. The integrated anchoring and grouting support system for roadways with fractured surrounding rock according to claim 1, characterized in that, The anchor cable (21) is located at the center of the third mounting hole (29), and a pair of limiting rings (24) are welded to the outside of the anchor cable (21). The anchor cable (21) has a through hole reserved inside.

7. The integrated anchoring and grouting support system for roadways with fractured surrounding rock according to claim 1, characterized in that, The protective cover (28) is located between the broadband velocity sensor (22) and the three-component accelerometer (23). An anchor cable (21) between a pair of limiting rings (24) is surrounded by a third inlet (26), and the third inlet (26) passes through the anchor cable (21) and extends to the through hole inside the anchor cable (21). A filling cavity (25) is provided between the pair of limiting rings (24).

8. The integrated anchoring and grouting support system for roadways with fractured surrounding rock according to claim 3, characterized in that, The anchor cable (6) consists of a support rod (16), a metal rod (17), and a hoop (18). The support rod (16) is located in the middle of the first mounting hole (9). Four metal rods (17) are evenly distributed around the support rod (16). The hoop (18) is wrapped around the outer wall of the metal rod (17) and the support rod (16).

9. The integrated anchoring and grouting support system for roadways with fractured surrounding rock according to claim 8, characterized in that, The support rod (16) has a second inlet (19) that runs through its interior.

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