CN204371386U - The inside and outside two note formula prestressed anchor Cable Structure of a kind of roadway floor - Google Patents

Abstract

A double-injection prestressed anchor cable structure inside and outside the bottom plate of the roadway; the structure passes through the grouting reinforcement area, the grout stop layer, the floor layer and the gravel layer, and drilled holes are drilled, and anchor cables are inserted in the holes. The anchor cable is equipped with a lock and an outer sleeve. The outer sleeve is equipped with an inner grouting pipe and an outer grouting pipe. The floor layer is even, and the upper end of the anchor cable, the lock, the outer grouting pipe and the upper end of the inner grouting pipe are all exposed to the floor layer. The three-hole flat tray is set on the floor layer and fixed on the outside of the outer casing and the outside of the anchor cable. , respectively filled and fixed by quick-hardening cement and cement grout, and shallow-hole grouting pipes are inserted downward on the grout-stop layer and the floor layer. This structure can not only carry out bottom sag treatment, realize the high prestress of the anchor cable in a long range; but also improve the ability of the surrounding rock of the floor to resist deformation and damage due to the influence of horizontal pressure and dynamic pressure, and prevent the anchor cable from corrosion.

Description

A double-injection prestressed anchor cable structure inside and outside the floor of the roadway

technical field

The utility model relates to an anchor cable structure for supporting and reinforcing the bottom plate of a soft rock roadway in a coal mine, in particular to a double-injection prestressed anchor cable structure inside and outside the bottom plate of a roadway which is applied in deep areas with high ground pressure and rich water.

Background technique

The underground mining depth of my country's coal mines is increasing at a rate of 8-12m per year. Under the conditions of deep high ground pressure and high dynamic pressure mining, the bottom of the soft rock roadway is severe. The muddy disintegration of the argillaceous rock has been prevented, and the amount of bottom scum is as high as 1.5-2m. The circulation undercover increases the maintenance cost of the roadway, seriously affects the normal use of the roadway, and the safety problem is extremely prominent.

At present, the methods used for the treatment of roadway bottom can be roughly divided into pressure relief method, reinforced support method and combined support method, and the method of anchoring and grouting reinforcement of the floor with anchor cables is the most widely used because of its convenient construction and remarkable treatment effect. In order to achieve high prestress of the anchor cable, the end of the anchor cable must be anchored before the prestress can be applied. The following three methods can be used to achieve high prestress of the anchor cable by using ordinary anchor cables: 1) After the drilling of the bottom plate is completed, use cement The grout is grouted within a certain depth of the borehole for anchoring, and then prestress is applied; 2) After the bottom plate drilling is completed, the resin anchoring agent is used to anchor the anchor cable within a certain range of depth, and then prestress is applied; 3) Base plate drilling construction After completion, use rubber plugs for deep hole sealing, pressurize grouting and anchor, and finally apply prestress.

Under the condition of rich water in the bottom plate, there is a large amount of groundwater and construction water in the borehole, and it will quickly accumulate after being pumped out. Obviously, the above method has the following three outstanding problems: First, the traditional grouting anchoring and anchoring agent are affected by water. Effective implementation, the anchoring effect is extremely poor; second, the rubber plug cannot be in close contact with the borehole wall, serious grout leakage, low grouting pressure, and poor anchoring effect; third, if the shallow hole is directly sealed and then pressure grouted, Post-tensioning the anchor cable can ensure the grouting effect and achieve full-length anchoring, but it cannot achieve high prestress in a long range of the anchor cable. Therefore, it can be seen that using ordinary anchor cables and the current anchoring and sealing technology cannot achieve high prestress in a long range of floor anchor cables .

Contents of the invention

In order to overcome the disadvantages of using ordinary anchor cables and the current anchoring and sealing technology in the prior art that cannot realize the high prestress of the floor anchor cables in a long range, the utility model provides a double-injection prestress on the inside and outside of the roadway floor Anchor cable structure, the double-injection prestressed anchor cable structure inside and outside the roadway floor is used to realize the high prestress of the floor anchor cable in a long range, thereby improving the stress state and mechanical properties of the roadway floor surrounding rock, and improving the roadway floor rock. The self-supporting capacity ensures the integrity and stability of the surrounding rock of the floor.

The technical scheme adopted by the utility model to solve the technical problem is: the double-injection prestressed anchor cable structure inside and outside the roadway bottom plate includes a gravel layer, a floor layer, an anchor cable, an upper end of an anchor cable, a lock, a three-hole flat tray, Shallow hole grouting pipe, cotton yarn, inner grouting pipe, outer casing, marisan, outer grouting pipe, cement slurry, lower end of anchor cable, drill hole, rapid hardening cement, grout stop layer and grouting reinforcement area; the roadway The double-injection prestressed anchor cable structure inside and outside the bottom plate passes through the grouting layer in the middle of the deep grouting 18 reinforcement area, the floor layer and the upper gravel layer, and drills a 6-21m deep hole, directly to the grouting reinforcement area; a 6-20m long cylindrical anchor cable is inserted in the borehole, and the outer periphery of the anchor cable is sequentially set with a lock and an outer casing. The outer casing is equipped with an inner grouting pipe and an outer grouting pipe. Lisan is fixed and closed, and the upper end of the outer casing is filled and fixed by cotton yarn. The upper end of the outer casing is flush with the floor layer. The three-hole flat tray set is laid flat on the floor level and fixed on the outside of the casing and the anchor cable; the outside of the casing is filled and fixed by rapid hardening cement and cement grout from top to bottom, and is fixed on the slurry layer and the floor. Shallow-hole grouting pipes are evenly inserted downwards on the top of the layer, and filled and reinforced by grouting to the grout-stop layer.

The outer diameter of the outer casing is 65-75mm, which is 10-25mm smaller than the borehole diameter, the inner diameter of the outer casing is 60-70mm, and the length of the outer casing is 3-10m.

The outer diameter of the anchor cable is 20-30mm, the length is 6-20m, and the length of the outer casing and the upper end of the anchor cable protruding from the outer casing is 50-200mm.

The beneficial effects of the utility model are: the double-injection prestressed anchor cable structure inside and outside the floor of the roadway not only provides an anchor cable structure for bottom swell treatment under the condition of deep high ground pressure and water-rich floor, but also uses the anchor cable structure for bottom In order to improve the internal friction angle and cohesion of the floor rock, the deep high-pressure grouting through the external grouting pipe of the structure can realize the high prestress of the anchor cable in a long range after double injection inside and outside the casing. The high prestress of the anchor cable can transform the rock within a certain range of the floor of the roadway from a two-way stress state and a low confining pressure three-way stress state to a three-way stress state with high confining pressure, which greatly improves the resistance factor of the floor surrounding rock. The ability to be deformed and destroyed by the influence of horizontal pressure and dynamic pressure; and the grouting through the grouting pipe in the structure can fill the gap between the anchor cable and the casing to prevent the anchor cable from being affected by water and corrosion.

Description of drawings

Below in conjunction with accompanying drawing, the utility model is further described.

Figure 1 is a schematic structural view of the utility model.

Figure 2 is a cross-sectional view of the anchor cable structure.

In the figure 1. gravel layer, 2. floor layer, 3. anchor cable, 4. upper end of anchor cable, 5. lock, 6. three-hole flat tray, 7. shallow hole grouting pipe, 8. cotton yarn, 9. Inner grouting pipe, 10. Outer casing, 11. Ma Lisan, 12. Outer grouting pipe, 13. Cement slurry, 14. Lower end of anchor cable, 15. Drilling, 16. Rapid hardening cement, 17. Grouting layer , 18. Grouting reinforcement area.

Detailed ways

In the figure, a double-injection prestressed anchor cable structure inside and outside the floor of the roadway, including: gravel layer 1, floor layer 2, anchor cable 3, anchor cable upper end 4, lock 5, three-hole flat tray 6, shallow hole Grouting pipe 7, cotton yarn 8, inner grouting pipe 9, outer casing 10, Ma Lisan 11, outer grouting pipe 12, cement slurry 13, anchor cable lower end 14, drilling 15, rapid hardening cement 16, grout stop layer 17 and grouting reinforcement area 18; the double-injection prestressed anchor cable structure inside and outside the floor of the roadway passes through the deep grouting reinforcement area 18, the grouting layer 17 in the middle, the floor layer 2 and the upper gravel layer 1. There is a 6-21m deep borehole 15, directly to the grouting reinforcement area 18; a 6-20m long cylindrical anchor cable 3 is inserted in the borehole 15, and the outer periphery of the anchor cable 3 is sequentially set with a lock 5 and an outer sleeve 10, The outer casing 10 is equipped with an inner grouting pipe 9 and an outer grouting pipe 12. The lower end of the outer casing 10 is fixed and closed by Ma Lisan 11, and the upper end of the outer casing 10 is filled and fixed by cotton yarn 8. The upper end of the outer casing 10 is connected to the ground. The floor layer 2 is flush, the upper end of the anchor cable 4, the lock 5, the outer grouting pipe 12 and the upper end of the inner grouting pipe 9 are all exposed to the floor layer 2, and the three-hole flat tray 6 is set on the floor layer 2. , fixed on the outer casing 10 and the anchor cable 3; the outer casing 10 is filled and fixed by rapid hardening cement 16 and cement slurry 13 from top to bottom, and is uniformly applied downward on the grout stop layer 17 and the floor layer 2. The shallow hole grouting pipe 7 is inserted, and the grouting layer 17 is grouted for filling and reinforcement.

The outer diameter of the outer casing 10 is 65-75mm, which is 10-25mm smaller than that of the borehole 15, the inner diameter of the outer casing 10 is 60-70mm, and the length of the outer casing 10 is 3-10m.

The outer diameter of the anchor cable 3 is 20-30mm, the length is 6-20m, and the length of the outer casing 10 and the upper end 4 of the anchor cable extending out of the outer casing 10 is 50-200mm.

Claims (3)

1. the inside and outside two note formula prestressed anchor Cable Structure of a kind of roadway floor, comprises macadam (1), terrace floor (2), anchor cable (3), anchor cable upper end (4), lockset (5), three hole flat pallets (6), Shallow hole grouting pipe (7), cotton yarn (8), interior Grouting Pipe (9), outer tube (10), Ma Lisan (11), outer Grouting Pipe (12), cement grout (13), anchor cable lower end (14), boring (15), rapid setting cement (16), grouting floor (17) and grouting and reinforcing district (18), it is characterized in that: through the macadam (1) on the grouting floor (17) at grouting and reinforcing district, deep (18), middle part, terrace floor (2) and top, bore the boring (15) of digging and having 6 ~ 21m dark, directly arrive grouting and reinforcing district (18), the anchor cable (3) of the oval column of 6 ~ 20m is fitted with in boring (15), the peripheral order of anchor cable (3) is set with lockset (5) and outer tube (10), outer tube (10) is built with interior Grouting Pipe (9) and outer Grouting Pipe (12), inner by Ma Lisan (11) fixed closed in outer tube (10) lower end, in outer tube (10) upper end, inner filling by cotton yarn (8) is fixed, outer tube (10) upper end is also concordant with terrace layer (2), anchor cable upper end (4), lockset (5), terrace layer (2) is all exposed in outer Grouting Pipe (12) and interior Grouting Pipe (9) upper end, and be laid on terrace layer (2) face by three hole flat pallets (6) suits, be fixed on outer tube (10) outside and anchor cable (3) outside, outer tube (10) outside is from top to bottom fixed by rapid setting cement (16) and cement grout (13) filling and blocking respectively, is above evenly fitted with Shallow hole grouting pipe (7) downwards at grouting layer (17) and terrace layer (2).

2. the inside and outside two note formula prestressed anchor Cable Structure of roadway floor according to claim 1, it is characterized in that: outer tube (10) is outward through being 65 ~ 75mm, 10 ~ 25mm less of boring (15) aperture, through being 60 ~ 70mm in outer tube (10), outer tube (10) length is 3 ~ 10m.

3. the inside and outside two note formula prestressed anchor Cable Structure of roadway floor according to claim 1, it is characterized in that: anchor cable (3) external diameter is 20 ~ 30mm, length is 6 ~ 20m, and the length that outer tube (10) is stretched out in outer tube (10) and anchor cable upper end (4) is 50 ~ 200mm.