Multi-point combined prestressed anchor bolt assembly and construction method for roadway support

Abstract

This invention discloses a multi-point combined prestressed anchor bolt assembly for roadway support and its construction method. The assembly includes an anchor bolt body, an anchor bolt expansion cap, and an outer support frame. One end of the anchor bolt body has a wedge-shaped expansion embedding part, and the other end is a support locking part. The wedge-shaped expansion embedding part has an inner sliding hole that slides in conjunction with an inner lining expansion column. A slider is also slidably installed in the inner sliding hole of the wedge-shaped expansion embedding part. A linkage rod is fixed to the slider, and a spring is fixed to the end of the linkage rod away from the slider. The spring is positioned and fixed to the bottom of the inner sliding hole of the wedge-shaped expansion embedding part. Several tightening connecting rod assemblies are sequentially installed along the length of the linkage rod. Each tightening connecting rod assembly includes a tightening fixing rod, and the wedge-shaped expansion embedding part has a tightening rod moving hole for the extension movement of the tightening fixing rod. This invention has multiple prestressed fastening points, improving the structural performance of roadway surrounding rock support and enabling it to cope with complex roadway rock strata conditions.

Description

Technical Field

[0001] This invention relates to the field of coal mine roadway support technology, and in particular to a multi-point combined prestressed fastening roadway support anchor assembly and its construction method. Background Technology

[0002] Rock bolts are a commonly used technical device in coal mine roadway support. Their working principle is as follows: after anchoring the bolt to the deep, stable surrounding rock, the bolt tray, fastened to the bolt's tail, inhibits the loosening and fracturing of the surrounding rock mass on the roadway surface. Simultaneously, it connects the roadway surface surrounding rock with the deep, stable rock, forming a stable load-bearing structure, thus supporting the roadway's surrounding rock mass. Rock bolt support technology plays a crucial role in reducing the amount of support structures within the roadway, lowering roadway support costs, and improving roadway excavation efficiency. Due to the wide applicability of its working principle, rock bolts are also used in slopes, tunnels, highways, and other areas requiring surrounding rock reinforcement. In the initial stage of coal mine roadway excavation, the sudden removal of the load-bearing structure within the roadway space leads to rapid deformation of the surrounding rock. Timely early roadway support can effectively reduce early and later deformation. Therefore, early, rapid, and timely support technology has always been a key research direction in roadway support. For conventional anchor bolt support, after the anchor bolt holes are drilled, anchoring agent needs to be added to the holes before the anchor bolts are driven in. The anchor bolts can only provide support after the anchoring agent has solidified. During the anchoring and solidification period, the surrounding rock of the roadway cannot be effectively supported, which will increase the early deformation of the surrounding rock, increase the difficulty of roadway support, and be detrimental to the later maintenance of the roadway.

[0003] Prestressed rock bolts are constructed by adding a prestressing device to the top of the bolt. After the bolt body is driven into the surrounding rock of the roadway, the device, through mechanical or frictional action with the bolt hole wall, immediately generates prestress upon installation. This prestress inhibits deformation and damage to the surrounding rock, thus providing early support for the roadway. As coal mining progresses to deeper levels, the stress level of the surrounding rock increases, and the early deformation of the surrounding rock significantly increases. However, traditional prestressed rock bolts have relatively few points of tension and friction between the prestressing device and the bolt hole. Under the stress environment of deep mining, these points are prone to failure, leading to bolt failure. Therefore, there is an urgent need to develop prestressed rock bolts with multiple tension and friction points to enhance their resistance to deformation and damage of the surrounding rock at the prestressing location. This allows for a continuous supply of prestressing force to the surrounding rock, effectively reducing early deformation and strengthening roadway support, thus aiding in the support of roadways in deep coal mining. Summary of the Invention

[0004] The purpose of this invention is to solve the technical problems pointed out in the background art, and to provide a multi-point combined prestressed fastening roadway support anchor bolt assembly and construction method. The wedge-shaped expansion insert and the wedge-shaped expansion cap of the anchor bolt are fitted together to form a prestressed expansion positioning at the bottom of the anchor hole. Several top-tightening connecting rod assemblies are installed on the linkage rod along the length of the anchor bolt body. The top-tightening fastening rods hold various positions along the length of the anchor hole to form multiple prestressed fastening points, realizing multi-point prestressed expansion positioning of the anchor bolt and the anchor bolt hole. This enhances the anchor bolt's resistance to deformation and damage of the surrounding rock strata, and allows the anchor bolt to continuously generate pre-tightening force after the support is completed, greatly improving the structural performance of the roadway surrounding rock support.

[0005] The objective of this invention is achieved through the following technical solution:

[0006] A multi-point combined prestressed fastening roadway support anchor bolt assembly includes an anchor bolt body, an anchor bolt expansion cap, and an outer support frame. One end of the anchor bolt body has a wedge-shaped expansion embedding portion, and the other end is a support locking portion. The anchor bolt expansion cap has a wedge-shaped expansion cavity formed by several wedge-shaped expansion arms. An inner lining expansion column is fixed within the wedge-shaped expansion cavity from the bottom to the opening. The wedge-shaped expansion embedding portion has an inner sliding hole that slides with the inner lining expansion column. A slider is also slidably mounted in the inner sliding hole of the wedge-shaped expansion embedding portion. A linkage rod is fixed to the slider, and a spring is fixed to the end of the linkage rod furthest from the slider. The spring is positioned and fixed at the bottom of the inner sliding hole of the wedge-shaped expansion insert; several clamping connecting rod assemblies are sequentially installed along the length of the linkage rod, each clamping connecting rod assembly including a clamping fastening rod, and the wedge-shaped expansion insert has a clamping rod moving hole for the clamping fastening rod to extend; when the spring is not compressed, the distance between the end of the linkage rod and the bottom of the inner sliding hole reaches its maximum value and the clamping fastening rod does not extend out of the clamping rod moving hole; when the spring is compressed to its position, the distance between the end of the linkage rod and the bottom of the inner sliding hole reaches its minimum value and the end of the clamping fastening rod extends out from the clamping rod moving hole and serves as a prestressed fastening point; the outer tray frame is positioned and installed on the support locking part of the anchor bolt body.

[0007] To better realize the roadway support anchor bolt assembly of the present invention, the tightening connecting rod assembly further includes a connecting rod seat. The connecting rod seat of the tightening connecting rod assembly is fixed on the linkage rod. Several connecting rods are circumferentially distributed and hinged on the connecting rod seat of the tightening connecting rod assembly, and the end of each connecting rod is hinged to the tightening fixing rod.

[0008] Preferably, the portion of the anchor bolt body located in the middle, excluding the wedge-shaped expansion insert and the support locking portion, is the anchor bolt body. The inner sliding hole extends from the wedge-shaped expansion insert to a portion of the anchor bolt body. Multiple tightening connecting rod assemblies are evenly distributed on the linkage rod, with some of the tightening connecting rod assemblies corresponding to the tightening rod moving holes of the wedge-shaped expansion insert. The anchor bolt body has a tightening rod moving hole, and another portion of the tightening connecting rod assemblies corresponds to the tightening rod moving holes of the anchor bolt body.

[0009] Preferably, the section of the inner sliding hole of the wedge-shaped expansion insert near the orifice is a triangular self-locking section. The inner wall of the triangular self-locking section of the wedge-shaped expansion insert has several annular positive triangular bodies 1 along the length direction, and the outer wall of the inner lining expansion column has several inverted triangular bodies along the length direction. When the wedge-shaped expansion insert moves toward the bottom of the wedge-shaped expansion cavity, the triangular hypotenuse A of the positive triangular body 1 first contacts the triangular hypotenuse B of the inverted triangular body in parallel. With further movement, the triangular hypotenuse A of the positive triangular body 1 passes over the triangular hypotenuse B of the inverted triangular body to complete one step of self-locking operation.

[0010] Preferably, the diameter of the inner lining expansion column gradually decreases from the bottom of the wedge-shaped expansion cavity to the opening; the diameter of the triangular self-locking section of the wedge-shaped expansion insert remains consistent or gradually decreases from the opening to the end of the triangular self-locking section.

[0011] Preferably, an elastic self-locking component is fixed at one end of the linkage rod near the spring. The elastic self-locking component has several elastically spread spring plates, each spring plate having a ball head at its end that elastically slides in contact with the wall of the inner sliding hole. The wall of the inner sliding hole has an annular limiting groove. When the spring is not compressed, the distance between the end of the linkage rod and the bottom of the inner sliding hole is at its maximum value. At this time, the spring plates of the elastic self-locking component are elastically compressed and the ball head is in elastic contact with the wall of the inner sliding hole. When the spring is compressed to its maximum value, the distance between the end of the linkage rod and the bottom of the inner sliding hole is at its minimum value. At this time, the ball head of the elastic self-locking component falls into the annular limiting groove of the inner sliding hole and is limited and locked.

[0012] Preferably, the outer pallet frame includes a pallet frame and a pallet plate mounted on the pallet frame, the pallet frame having a rod sleeve in the middle that cooperates with the support locking part, and the pallet plate having a rod hole that cooperates with the support locking part.

[0013] Preferably, the support locking part has external threads, and a locking nut is threaded onto the support locking part, with the locking nut end side limiting and supporting the end side of the pallet frame's sleeve.

[0014] A construction method for a multi-point combined prestressed fastening roadway support anchor assembly, comprising the roadway support anchor assembly, the method comprising:

[0015] S1. Plan several anchor bolt support points in the area to be supported in the coal mine roadway, drill anchor bolt holes in the coal mine roadway at the anchor bolt support points, and drive the anchor bolt expansion cap into the bottom of the anchor bolt hole.

[0016] S2. Drive the anchor bolt body into the anchor bolt hole. The wedge-shaped expansion insert of the anchor bolt body enters the wedge-shaped expansion cavity of the anchor bolt expansion cap. As the wedge-shaped expansion insert of the anchor bolt body enters, the wedge-shaped expansion insert continuously expands to form various wedge-shaped expansion arms around the wedge-shaped expansion cavity. The various wedge-shaped expansion arms of the anchor bolt expansion cap expand outward and are prestressed and fastened to the anchor bolt hole. At the same time, the inner lining expansion column of the anchor bolt expansion cap pushes the slider and linkage rod to move towards the spring. The spring is compressed, and the ends of the top-tightening rods of each top-tightening linkage assembly gradually extend from the top-tightening rod moving hole and are prestressed and held at the corresponding points of the anchor bolt hole, forming prestressed fastening points distributed along the length of the anchor bolt body. The anchor bolt body construction is completed when the anchor bolt body is driven into place.

[0017] S3. Install and fix the outer pallet frame on the support locking part of each anchor bolt body in the area to be supported, and construct the roadway support structure by combining the various outer pallet frames in the area to be supported.

[0018] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0019] (1) The wedge-shaped expansion embedding part and the wedge-shaped expansion cap of the present invention form a prestressed expansion positioning at the bottom of the anchor hole. Several top-tightening connecting rod assemblies are installed on the linkage rod along the length direction of the anchor body. The top-tightening fixing rods hold various positions along the length direction of the anchor hole to form multiple prestressed fastening points, thereby realizing the multi-point prestressed expansion positioning of the anchor and the anchor hole, enhancing the anchor's resistance to deformation and damage of the surrounding rock strata, and enabling the anchor to continuously generate pre-tightening force after the support is completed, which greatly improves the structural performance of the roadway surrounding rock support.

[0020] (2) The inner wall of the triangular self-locking section of the wedge-shaped expansion embedding part of the present invention is provided with several annular positive triangular bodies along the length direction, and the outer wall of the inner lining expansion column is provided with several inverted triangular bodies along the length direction. This ensures that after the wedge-shaped expansion embedding part is embedded and installed in place, the wedge-shaped expansion embedding part will not retract and can maintain the prestressed expansion and fastening state in a self-locking manner. This prevents the rock strata deep in the roadway anchor hole from being damaged, which would cause the wedge-shaped expansion embedding part to retract and loosen. This effectively improves the overall performance of the anchor support structure and can cope with the complex situation of the roadway rock strata.

[0021] (3) An elastic self-locking component is fixed at one end of the linkage rod near the spring. The elastic self-locking component has a ball head that is elastically supported by a spring. The inner sliding hole has an annular limiting groove. When the spring is compressed to the position, the ball head falls into the annular limiting groove of the inner sliding hole and is locked. The spring is always in a compressed state. The top-tightening rods of each top-tightening linkage assembly always extend out of the top-tightening rod moving hole and prestress the anchor hole. The failure of the anchor bolt tension cap will not affect the tightening operation of other prestressed tightening points. It can cope with the complex situation of the roadway rock strata.

[0022] (4) The present invention has multiple prestressed fastening points, which have strong resistance to the failure of anchor bolts caused by deformation and damage of the surrounding rock at the location where prestress is generated, and provide continuous pre-tightening force for roadway support, thereby improving the structural performance of roadway surrounding rock support. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the structure of the first embodiment of the roadway support anchor bolt assembly of the present invention;

[0024] Figure 2 This is a schematic diagram of the structure of the anchor body and the anchor expansion cap when the wedge-shaped expansion insert is just inserted.

[0025] Figure 3 for Figure 2 A partially enlarged schematic diagram of the location of the wedge-shaped expansion and embedding part;

[0026] Figure 4 for Figure 2 A partially enlarged schematic diagram of the middle annular limiting groove;

[0027] Figure 5 This is a schematic diagram of the structure when the wedge-shaped expansion insert is inserted into place;

[0028] Figure 6 for Figure 5 A partially enlarged schematic diagram of the location of the wedge-shaped expansion and embedding part;

[0029] Figure 7 A three-dimensional structural diagram of mounting a clamping connecting rod assembly on the linkage rod;

[0030] Figure 8 This is a schematic diagram of the structure of the second embodiment of the roadway support anchor bolt assembly of the present invention.

[0031] The names corresponding to the reference numerals in the attached figures are as follows:

[0032] 1-Anchor bolt body, 11-Wedge-shaped expansion insert, 111-Forward triangular body, 12-Support locking part, 2-Anchor bolt expansion cap, 21-Wedge-shaped expansion cavity, 22-Inner lining expansion column, 221-Inverted triangular body, 23-Concave-convex friction point, 3-Inner sliding hole, 31-Tightening rod moving hole, 32-Annular limiting groove, 4-Slider, 5-Linkage rod, 6-Tightening connecting rod assembly, 61-Connecting rod seat, 62-Connecting rod, 63-Tightening fixing rod, 7-Spring, 8-Outer pallet frame, 81-Pallet plate, 9-Locking nut, 10-Elastic self-locking component, 101-Ball head, 102-Spring. Detailed Implementation

[0033] The present invention will be further described in detail below with reference to embodiments:

[0034] Example

[0035] like Figures 1 to 7 As shown, a multi-point combined prestressed anchor bolt assembly for roadway support includes an anchor bolt body 1, an anchor bolt expansion cap 2, and an outer tray frame 8. One end of the anchor bolt body 1 has a wedge-shaped expansion insertion part 11 (the wedge-shaped expansion insertion part 11 engages with the anchor bolt expansion cap 2 in a wedge-shaped fit, expanding the anchor bolt expansion cap 2 and prestressing it in the anchor hole). The other end of the anchor bolt body 1 has a support locking part 12 (the support locking part 12 is used for roadway support installation). The anchor bolt expansion cap 2 has a wedge-shaped expansion cavity 21 formed by several wedge-shaped expansion arms (when the wedge-shaped expansion insertion part 11 is inserted into the wedge-shaped expansion cavity 21, each wedge-shaped expansion arm of the anchor bolt expansion cap 2 expands and is prestressed and firmly fixed in the anchor hole). An inner lining expansion column 22 (such as...) is fixed from the bottom to the opening of the wedge-shaped expansion cavity 21 of the anchor bolt expansion cap 2. Figure 2 As shown, the inner lining expansion pin 22 is placed in the wedge-shaped expansion cavity 21. The bottom of the inner lining expansion pin 22 is fixed to the bottom of the wedge-shaped expansion cavity 21, and the top of the inner lining expansion pin 22 is flush with the opening of the wedge-shaped expansion cavity 21. The wedge-shaped expansion cavity 21, excluding the portion with the inner lining expansion pin 22, forms a wedge-shaped insertion cavity corresponding to the wedge-shaped expansion insertion part 11. The wedge-shaped expansion insertion part 11 has an inner sliding hole 3 inside. The inner sliding hole 3 of the wedge-shaped expansion insertion part 11 is slidably engaged with the inner lining expansion pin 22 (during assembly, the inner lining expansion pin 22 extends into the inner sliding hole 3). A slider 4 is also slidably installed in the inner sliding hole 3 of the wedge-shaped expansion insertion part 11 (when the inner lining expansion pin 22 extends into the inner sliding hole 3 and can hold the slider 4, as the wedge-shaped expansion insertion part 11 moves into place, the inner lining expansion pin 22 pushes the slider 4 to slide in the inner sliding hole 3).

[0036] like Figure 2As shown, a linkage rod 5 is fixed to the slider 4. A spring 7 is fixed to the end of the linkage rod 5 away from the slider 4 (that is, the end away from the anchor bolt tension cap 2). The spring 7 is positioned and fixed at the bottom of the inner sliding hole 3 of the wedge-shaped tensioning insert 11. Several clamping linkage assemblies 6 are installed sequentially along the length of the linkage rod 5. The clamping linkage assembly 6 includes a clamping fastening rod 63. The wedge-shaped tensioning insert 11 has a clamping rod moving hole 31 for clamping the fastening rod 63 to extend (the diameter of the clamping rod moving hole 31 is larger than that of the wedge-shaped tensioning insert 11, and the wedge-shaped tensioning insert 11 can adapt to the extension and retraction movement in the clamping rod moving hole 31, and the clamping rod moving hole 31 can cope with the extension and retraction movement of the wedge-shaped tensioning insert 11 with a certain inclination). When the spring 7 is not compressed, the distance between the end of the linkage rod 5 and the bottom of the inner sliding hole 3 reaches its maximum value and the top fastening rod 63 does not extend out of the top fastening rod moving hole 31. At this time, the top fastening rod 63 is almost flush with the outer wall of the anchor rod body 1, and the slider 4 is not held and slid by the inner lining expansion column 22. When the spring 7 is compressed to its maximum position (the present invention has a maximum compression position, which is positioned by the elastic self-locking part 10 and the annular limiting groove 32), the distance between the end of the linkage rod 5 and the bottom of the inner sliding hole 3 reaches a minimum value, and the end of the top-tightening rod 63 extends out from the top-tightening rod moving hole 31 and serves as a prestressed fastening point; at this time, the top-tightening rod 63 extends out from the top-tightening rod moving hole 31 and extends beyond the outer wall of the anchor body 1 and is tightly held and positioned against the anchor hole wall. One prestressed anchor hole wall position of the end of the top-tightening rod 63 is a prestressed fastening point. With multiple top-tightening linkage components 6 on the linkage rod 5, multiple prestressed fastening points are formed. In this way, even if there is a collapse or geological loosening at the position of the anchor bolt expansion cap 2, each prestressed fastening point will ensure that the roadway support anchor bolt assembly is tightly fixed in the roadway rock, greatly enhancing the anchor bolt support capacity of the roadway support anchor bolt assembly. The outer pallet frame 8 is positioned and installed on the support locking part 12 of the anchor bolt body 1. The outer pallet frame 8 can be used for the construction and installation of the support structure layer.

[0037] In some embodiments, such as Figure 7 As shown, the clamping linkage assembly 6 also includes a linkage seat 61. The linkage seat 61 of the clamping linkage assembly 6 is fixed to the linkage rod 5. Several linkages 62 are hinged in a circular arrangement on the linkage seat 61 of the clamping linkage assembly 6. See [link to previous section] Figure 7 A connecting rod seat 61 is hinged to four connecting rods 62. Each connecting rod 62 is hinged to a top fastening rod 63 at its end. All four connecting rods 62 are hinged to top fastening rods 63 at their ends. The four top fastening rods 63 are circumferentially symmetrically positioned at four points of prestress and are tightly fixed to the anchor holes.

[0038] In some embodiments, such as Figure 8As shown, the portion of the anchor bolt body 1 located in the middle, excluding the wedge-shaped expansion insert 11 and the support locking part 12, is the anchor bolt body. The inner sliding hole 3 extends from the wedge-shaped expansion insert 11 to a portion of the anchor bolt body. Figure 1 In the first embodiment, the inner sliding hole 3 is slightly longer than the wedge-shaped expansion insert 11, and the clamping connecting rod assembly 6 is mainly concentrated at the corresponding position of the wedge-shaped expansion insert 11; Figure 8 In the second implementation, the inner sliding hole 3 is longer than the wedge-shaped tightening insert 11, allowing it to cover more of the anchor bolt body depending on the specific conditions of the roadway rock strata. This results in more tightening connecting rod assemblies 6 being installed on the linkage rod 5. More tightening connecting rod assemblies 6 create more prestressed fastening points, making the roadway support anchor bolt assembly more effectively fixed in the rock strata. Even if geological damage occurs at certain locations along the length of the anchor hole, it still provides strong anchor bolt support. Multiple tightening connecting rod assemblies 6 are evenly distributed on the linkage rod 5, with some of these assemblies corresponding to the tightening rod moving holes 31 of the wedge-shaped tightening insert 11. The anchor bolt body has tightening rod moving holes 31, and another portion of the tightening connecting rod assemblies 6 correspond to these tightening rod moving holes 31 on the anchor bolt body.

[0039] In some embodiments, such as Figure 2 , Figure 3 As shown, the inner sliding hole 3 of the wedge-shaped expansion insert 11 has a triangular self-locking section near the opening. The inner wall of the triangular self-locking section of the wedge-shaped expansion insert 11 has several annular positive triangular bodies 111 along its length, and the outer wall of the inner expansion insert 22 has several inverted triangular bodies 221 along its length. When the wedge-shaped expansion insert 11 moves towards the bottom of the wedge-shaped expansion cavity 21, the triangular hypotenuse A of the positive triangular body 111 first contacts the triangular hypotenuse B of the inverted triangular body 221 in parallel (e.g., ...). Figure 3 As shown, the positive triangular body 111 and the inverted triangular body 221 have a positive and negative wedge-shaped surface structure, making it easier for the positive triangular body 111 to step over the inverted triangular body 221. With further movement, the triangular hypotenuse A of the positive triangular body 111 steps over the triangular hypotenuse B of the inverted triangular body 221, completing a self-locking operation. Both the positive triangular body 111 and the inverted triangular body 221 have a ring structure. The positive triangular body 111 steps over the inverted triangular body 221 step by step and engages with the wedge-shaped tightening insert 11. However, the wedge-shaped tightening insert 11 cannot retract from the wedge-shaped tightening cavity 21 because once the positive triangular body 111 steps over the inverted triangular body 221, as... Figure 6As shown, under prestress, the large wedge-shaped end of the forward triangular body 111 and the large wedge-shaped end of the inverted triangular body 221 are precisely engaged, preventing the wedge-shaped tightening insert 11 from retracting. This invention employs the aforementioned self-locking structure, ensuring that once the wedge-shaped tightening insert 11 is properly installed, it will not retract, thus maintaining a self-locking, prestressed, and tightly secured state. This prevents the wedge-shaped tightening insert 11 from loosening due to rock strata damage deep within the roadway anchor hole.

[0040] like Figure 3 As shown, in some preferred embodiments, the diameter of the inner lining expansion column 22 gradually decreases from the bottom of the wedge-shaped expansion cavity 21 to the opening, such as... Figure 6 As shown, the cross-sectional size of the inner lining expansion column 22 decreases sequentially from the bottom to the opening of the wedge-shaped expansion cavity 21, forming a larger end near the bottom and a smaller end near the opening. The diameter of the triangular self-locking section of the wedge-shaped expansion insert 11 remains consistent or gradually decreases from the opening to the end of the triangular self-locking section.

[0041] In some embodiments, such as Figure 4 As shown, a resilient self-locking element 10 is fixed at one end of the linkage 5 near the spring 7. The resilient self-locking element 10 has several elastically extended spring pieces 102 (such as...). Figure 4 As shown, the spring 102 is elastically spread out at an angle. Each spring 102 has a ball head 101 at its end that is elastically sliding in contact with the wall of the inner sliding hole 3. The wall of the inner sliding hole 3 has an annular limiting groove 32. When the spring 7 is not compressed, the distance between the end of the linkage rod 5 and the bottom of the inner sliding hole 3 is at its maximum value. At this time, the spring 102 of the elastic self-locking member 10 is elastically compressed and the ball head 101 is elastically in contact with the wall of the inner sliding hole 3 (as the slider 4 pushes the linkage rod 5 to move, the ball head 101 elastically slides on the wall of the inner sliding hole 3). When the spring 7 is compressed to its position, the distance between the end of the linkage rod 5 and the bottom of the inner sliding hole 3 is at its minimum. At this time, the ball head 101 of the elastic self-locking component 10 falls into the annular limiting groove 32 of the inner sliding hole 3 and is locked in place. The spring 102 of the elastic self-locking component 10 is elastically compressed, so the ball head 101 can easily fall into the annular limiting groove 32 of the inner sliding hole 3 when it slides to the position of the annular limiting groove 32. Once the ball head 101 falls in, it will not slide left or right from the annular limiting groove 32 under the action of the elastic force of the spring 102 and will be locked in place. When the ball head 101 falls into the annular limiting groove 32 of the inner sliding hole 3 and is locked in place, the spring 7 is always in a compressed state. The top tightening rods 63 of each top tightening linkage assembly 6 always extend out of the top tightening rod moving hole 31 and prestress the anchor hole. The tightening operation of other prestressed tightening points will not be affected by the failure of the anchor bolt tension cap 2. The outer wall of the anchor bolt expansion cap 2 of the present invention may be provided with concave and convex friction points 23 to enhance the friction performance with the anchor hole and strengthen the fastening performance.

[0042] like Figure 1 , Figure 8 As shown, the outer pallet frame 8 includes a pallet frame and a pallet plate 81 mounted on the pallet frame. The pallet frame has a sleeve in the middle that mates with the support locking part 12, and the pallet plate 81 has a rod hole that mates with the support locking part 12. The support locking part 12 has external threads, and a locking nut 9 is threaded onto the support locking part 12. The locking nut 9 limits and holds the end of the sleeve of the pallet frame.

[0043] A construction method for a multi-point combined prestressed fastening roadway support anchor assembly, including the roadway support anchor assembly of the present invention, the method comprising:

[0044] S1. Plan several anchor bolt support points in the area to be supported in the coal mine roadway. Drill anchor bolt holes in the coal mine roadway at the anchor bolt support points and drive the anchor bolt tightening cap 2 into the bottom of the anchor bolt hole.

[0045] S2. The anchor bolt body 1 is driven into the anchor bolt hole. The wedge-shaped expansion insert 11 of the anchor bolt body 1 enters the wedge-shaped expansion cavity 21 of the anchor bolt expansion cap 2. As the wedge-shaped expansion insert 11 of the anchor bolt body 1 enters, it continuously expands to form various wedge-shaped expansion arms in the wedge-shaped expansion cavity 21. The wedge-shaped expansion arms of the anchor bolt expansion cap 2 expand outward and are prestressed and tightened with the anchor bolt hole. At the same time, the inner lining expansion column 22 of the anchor bolt expansion cap 2 pushes the slider 4 and the linkage rod 5 to move towards the spring 7. The spring 7 is compressed, and the ends of the tightening rods 63 of each tightening linkage assembly 6 gradually extend from the tightening rod moving hole 31 and are prestressed and tightened at the corresponding points of the anchor bolt hole, forming prestressed tightening points distributed along the length of the anchor bolt body 1. The construction of the anchor bolt body 1 is completed when the anchor bolt body 1 is driven into place.

[0046] S3. Install and fix the outer pallet frame 8 on the support locking part 12 of each anchor bolt body 1 in the area to be supported, and construct the roadway support structure by combining the various outer pallet frames 8 in the area to be supported.

[0047] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A multi-point combined prestressed fastening roadway support anchor assembly, characterized in that: The system includes an anchor bolt body (1), an anchor bolt expansion cap (2), and an outer tray frame (8). One end of the anchor bolt body (1) has a wedge-shaped expansion insert (11), and the other end of the anchor bolt body (1) is a support locking part (12). The anchor bolt expansion cap (2) has a wedge-shaped expansion cavity (21) surrounded by several wedge-shaped expansion arms. An inner lining expansion column (22) is fixed in the wedge-shaped expansion cavity (21) from the bottom of the cavity to the opening of the cavity. The wedge-shaped expansion insert (11) has an inner sliding hole (3). The inner sliding hole (3) of the wedge-shaped expansion insert (11) is slidably engaged with the inner lining expansion column (22). A slider (4) is also slidably installed in the inner sliding hole (3) of the wedge-shaped expansion insert (11). The slider (4) is fixed with... A linkage rod (5) is attached to a spring (7) at one end away from the slider (4). The spring (7) is positioned and fixed at the bottom of the inner sliding hole (3) of the wedge-shaped expansion insert (11). Several clamping linkage assemblies (6) are installed sequentially along the length of the linkage rod (5). Each clamping linkage assembly (6) includes a clamping rod (63). The wedge-shaped expansion insert (11) has a clamping rod moving hole (31) for the clamping rod (63) to extend. When the spring (7) is not compressed, the distance between the end of the linkage rod (5) and the bottom of the inner sliding hole (3) reaches its maximum value and the clamping rod (63) does not extend out of the clamping rod moving hole (31). When the spring (7) is compressed to the position, the distance between the end of the linkage rod (5) and the bottom of the inner sliding hole (3) reaches its maximum value. The distance at the bottom of the hole (3) reaches a minimum value and the end of the top-tightening rod (63) extends from the top-tightening rod moving hole (31) and serves as a prestressing fastening point; the outer tray frame (8) is positioned and installed on the support locking part (12) of the anchor body (1); the part of the anchor body (1) in the middle, excluding the wedge-shaped expansion embedding part (11) and the support locking part (12), is the anchor body; the inner sliding hole (3) extends from the wedge-shaped expansion embedding part (11) to a part of the anchor body; multiple top-tightening connecting rod assemblies (6) are evenly distributed on the linkage rod (5), and a part of the top-tightening connecting rod assemblies (6) corresponds to the top-tightening rod moving hole (31) of the wedge-shaped expansion embedding part (11); the anchor body has a top-tightening rod moving hole. (31) Another part of the clamping rod assembly (6) corresponds to the clamping rod moving hole (31) of the anchor rod body; the linkage rod (5) is fixed with an elastic self-locking member (10) near the end of the spring (7). The elastic self-locking member (10) has several elastically spread springs (102). Each spring (102) has a ball head (101) at the end that elastically slides in contact with the hole wall of the inner sliding hole (3). The hole wall of the inner sliding hole (3) has an annular limiting groove (32). When the spring (7) is not compressed, the distance between the end of the linkage rod (5) and the bottom of the inner sliding hole (3) is at its maximum value. At this time, the springs (102) of the elastic self-locking member (10) are elastically compressed and the ball head (101) elastically contacts the hole wall of the inner sliding hole (3).When the spring (7) is compressed to its position, the distance between the end of the linkage rod (5) and the bottom of the inner sliding hole (3) is at its minimum. At this time, the ball head (101) of the elastic self-locking component (10) falls into the annular limiting groove (32) of the inner sliding hole (3) and is locked in place.

2. A multi-point combined prestressed fastening roadway support anchor assembly according to claim 1, characterized in that: The clamping link assembly (6) also includes a link seat (61). The link seat (61) of the clamping link assembly (6) is fixed on the linkage rod (5). Several links (62) are hinged in a circular arrangement on the link seat (61) of the clamping link assembly (6). The end of each link (62) is hinged to the clamping fastening rod (63).

3. The multi-point combined prestressed fastening roadway support anchor assembly according to claim 1, characterized in that: The inner sliding hole (3) of the wedge-shaped expansion insert (11) has a triangular self-locking section near the opening. The inner wall of the triangular self-locking section of the wedge-shaped expansion insert (11) is provided with several annular positive triangular bodies (111) along the length direction. The outer wall of the inner lining expansion column (22) is provided with several inverted triangular bodies (221) along the length direction. When the wedge-shaped expansion insert (11) moves toward the bottom of the wedge-shaped expansion cavity (21), the triangular hypotenuse A of the positive triangular body (111) first contacts the triangular hypotenuse B of the inverted triangular body (221) in parallel. As it moves further, the triangular hypotenuse A of the positive triangular body (111) passes over the triangular hypotenuse B of the inverted triangular body (221) to complete a self-locking operation.

4. The multi-point combined prestressed fastening roadway support anchor assembly according to claim 3, characterized in that: The diameter of the inner lining expansion column (22) gradually decreases from the bottom of the wedge-shaped expansion cavity (21) to the opening; the diameter of the triangular self-locking section of the wedge-shaped expansion embedding part (11) remains consistent or gradually decreases from the opening to the end of the triangular self-locking section.

5. The multi-point combined prestressed fastening roadway support anchor assembly according to claim 1, characterized in that: The outer pallet frame (8) includes a pallet frame and a pallet plate (81) mounted on the pallet frame. The pallet frame has a rod sleeve in the middle that cooperates with the support locking part (12), and the pallet plate (81) has a rod hole that cooperates with the support locking part (12).

6. The multi-point combined prestressed fastening roadway support anchor assembly according to claim 5, characterized in that: The support locking part (12) has an external thread, and a locking nut (9) is threadedly connected to the support locking part (12). The locking nut (9) is positioned and holds the end of the rod sleeve of the pallet frame.

7. A construction method for a multi-point combined prestressed fastening roadway support anchor bolt assembly, characterized in that: The method comprising the roadway support anchor assembly according to any one of claims 1 to 6 includes: S1. Plan several anchor bolt support points in the coal mine roadway to be supported area, drill anchor bolt holes in the coal mine roadway at the anchor bolt support points, and drive the anchor bolt tightening cap (2) into the bottom of the anchor bolt hole. S2. Drive the anchor body (1) into the anchor hole. The wedge-shaped expansion insert (11) of the anchor body (1) enters the wedge-shaped expansion cavity (21) of the anchor expansion cap (2) in a wedge shape. As the wedge-shaped expansion insert (11) of the anchor body (1) enters in a wedge shape, the wedge-shaped expansion insert (11) of the anchor body (1) continuously expands in a wedge shape to form each wedge-shaped expansion arm of the wedge-shaped expansion cavity (21). Each wedge-shaped expansion arm of the anchor expansion cap (2) expands outward and is prestressed and fastened to the anchor hole. At the same time, the inner lining expansion column (22) of the anchor bolt expansion cap (2) pushes the slider (4) and linkage rod (5) to move towards the spring (7), the spring (7) is compressed, and the ends of the top tightening rods (63) of each top tightening linkage assembly (6) gradually extend from the top tightening rod moving hole (31) and are prestressed and held at the corresponding points of the anchor bolt hole, forming prestressed fastening points distributed along the length of the anchor bolt body (1); until the anchor bolt body (1) is driven into place, the construction of the anchor bolt body (1) is completed; S3. Install fixed outer pallet frame (8) on the support locking part (12) of each anchor body (1) in the area to be supported, and construct the roadway support structure by combining the various outer pallet frames (8) in the area to be supported.

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