CN103089276A - Deep-shallow hole and high-low pressure coupling grouting technology - Google Patents

Abstract

The invention discloses a grouting technology coupled with deep and shallow holes and high and low pressure, which is suitable for grouting reinforcement of mine roadways, tunnels and other underground projects, and is especially suitable for grouting reinforcement of weak and broken surrounding rocks in roadways. In the coupling grouting process, a drill bit is used to drill a hole in the surrounding rock mass, and a shallow hole is first drilled; then an orifice pipe is inserted into the shallow hole, and the hole is sealed, and the orifice pipe is connected near the rock surface Spherical valve, the spherical valve is connected with the grouting device; after the orifice pipe is installed, respray the surrounding rock surface; perform low-pressure shallow hole grouting through the orifice pipe; after low-pressure shallow hole grouting, Remove the grouting device, use the drill bit to sweep the hole in the above-mentioned orifice pipe to form a deep hole; then perform high-pressure deep hole grouting through the orifice pipe; after the grouting is completed, spray the surrounding rock again to form a pair of orifice tube protection. The process is simple, safe, low in cost and remarkable in reinforcing effect.

Description

Deep and shallow holes and high and low pressure coupling grouting technology

technical field

The invention relates to a grouting process, in particular to a deep and shallow hole and high and low pressure coupling grouting process suitable for grouting reinforcement of weak and broken surrounding rocks in roadways. It belongs to the technical field of grouting reinforcement for underground engineering such as mine roadways and tunnels.

Background technique

With the increase of large-scale mining and mining depth, the problem of weak and broken surrounding rock roadway support has become increasingly prominent, such as mining areas in Huaibei, Huainan, Longkou, Xuzhou, Tiefa, Feicheng, Zaozhuang and other regions. Soft rock roadways generally have the characteristics of soft and broken surrounding rocks, large rheology; fast pressure time, large initial deformation, and long duration; surrounding rocks are easy to disintegrate when exposed to water, and their strength decreases sharply. If inappropriate maintenance measures are adopted, the deformation of the surrounding rock of the roadway will become more severe, which will eventually lead to the destruction of the roadway. Exploring a reasonable support method for soft rock roadways has become a major problem that needs to be solved urgently. the

The masonry and metal supports are all passive supports, and it is difficult to withstand the high ground stress if only relying on the strength of the support itself. Anchor rods and anchor cables are considered active support, but because the anchored rock mass is some broken or loose rock mass, the anchorability of the surrounding rock is poor, and it is difficult to meet the support requirements of deep soft rock roadways. In addition, the cost of masonry and metal supports is high, the construction speed is slow, and it is difficult to maintain after deformation or damage. Support methods such as large-diameter long anchor rods and long anchor cables require special equipment, and support costs are high when used in large quantities. The construction speed is slow, and it cannot be widely used in soft rock roadway support in my country.

Traditional grouting reinforcement adopts shallow hole grouting, or shallow hole and deep hole grouting pipes are arranged at intervals, the number of drilling and installation of grouting pipes is large, and the pressure is difficult to control during shallow hole and deep hole grouting. If the grouting pressure is too high If the injection pressure is too small, the grout injected into the broken surrounding rock is too small, and the broken surrounding rock cannot be cemented effectively. If the grouting pressure is too high, the rock mass will often be split and broken, and cracks will be formed around the surrounding rock, resulting in The slurry spilled from the surface of the surrounding rock.

To sum up, it is necessary to develop an efficient, operable, and economical grouting process for reinforcing weak and broken surrounding rock in underground engineering such as roadways.

Contents of the invention

Technical problem: The purpose of the present invention is to overcome the deficiencies in the prior art, and provide a simple, safe, low-cost, and remarkable reinforcement effect coupling grouting process for deep and shallow holes and high and low pressure. the

Technical solution: The deep and shallow hole and high and low pressure coupling grouting process of the present invention includes the following steps:

a. First drill a shallow hole in the surrounding rock body;

b. Insert the orifice in the shallow hole, seal the hole, and connect the exposed end of the orifice pipe with the grouting pipe;

c. Spray concrete to the rock surface around the orifice, so that the rock surface around the orifice forms a sealing layer for the orifice pipe;

d. Open the grouting control valve, and carry out low-pressure shallow hole grouting with pressure controlled at 2MPa~3MPa into the shallow hole through the orifice pipe, so that the grout can fully penetrate into the rock and soil around the shallow hole;

e. After the low-pressure shallow hole grouting is completed, 3 to 7 days after the low-pressure shallow hole grouting, remove the grouting pipe, use the drill bit to sweep the hole inward through the orifice pipe, and change the shallow hole into a deep hole; the deep hole The depth is determined according to the size of the surrounding rock loose circle and the degree of fragmentation of the surrounding rock;

f. After the deep hole grouting is completed, drill back, connect the grouting pipe, and carry out high-pressure deep hole grouting with the grout pressure controlled at 3MPa~5MPa into the deep hole through the orifice pipe, so that the grout can fully penetrate into the rock and soil around the deep hole , and coupled with the grout around the shallow hole to strengthen the rock and soil mass, the grouting material is mainly dilute cement grout, if the cracks in the surrounding rock are small, use ultra-fine cement or chemical grout;

g. After 3~7 days after the deep hole grouting is completed, the grouting pipe is removed, and the surrounding rock is resprayed with concrete. The thickness of the resprayed concrete is 30mm~50mm, and the surrounding rock is sealed to prevent the grout in the injection hole from seeping out, and ensure that the exposed length of the orifice pipe (6) is not less than 30 mm.

The depth of the shallow hole is 2000mm~3000mm, and the diameter of the shallow hole is 40mm~60mm;

The length of the orifice tube is 500mm~1000mm, and the diameter is 30mm~40mm;

The strength grade of the shotcrete is C25~C30;

The low-pressure shallow hole grouting slurry adopts cement slurry or cement-water glass composite slurry;

The depth of the deep hole is 5000mm~6000mm, and the drilling diameter is 20mm~30mm.

Beneficial effects: the present invention has a particularly remarkable grouting effect on broken soft surrounding rocks and large loose surrounding rocks. First, through the effective combination of low-pressure shallow holes and high-pressure deep holes for grouting in stages, low-pressure shallow holes and high-pressure deep holes are used in the same pipe The grouting is carried out in stages to reinforce the periphery of the severely broken loose circle. First, fill the grouting through low-pressure shallow holes, and use a small grouting pressure to ensure that the sprayed layer does not break and prevent the grout from overflowing. The cracks in the shallow surrounding rock, Filling the gap is equivalent to forming a thicker grouting wall, which can provide guarantee for deep hole high-pressure grouting; then use higher grouting pressure to carry out high-pressure deep-hole grouting, and use high-pressure deep-hole grouting to repair the deep hole. The fine cracks in the surrounding rock are reinforced by grouting, the scope of the grouting reinforcement is expanded, and the broken surrounding rock bodies within the loosening circle are cemented together to provide the inherent strength and stability of the surrounding rock. Fundamentally change the mechanical properties of the broken surrounding rock and improve its self-supporting capacity; in addition, after strengthening with the anchor rod (cable), the inner and outer ring bearing structures formed by the compression arch of the anchor rod and the deep bearing ring of the anchor cable are effectively combined Together, a high-strength, high-rigidity multi-layer anchor-shell composite arch structure is finally formed, which expands the bearing range of the support system and jointly maintains the long-term stability and safety of the weak and broken surrounding rock of the roadway.

Description of drawings:

Fig. 1 is the drilling schematic diagram of the present invention;

Fig. 2 is a schematic diagram of a borehole placement casing of the present invention;

Fig. 3 is the shallow hole grouting schematic diagram of the present invention;

Fig. 4 is a schematic diagram of deep hole formation of the present invention;

Fig. 5 is the deep hole grouting schematic diagram of the present invention;

Fig. 6 is a schematic diagram of sprayed concrete hole sealing according to the present invention.

In the figure: 1-drilling machine, 2-drill pipe, 3-surrounding rock mass, 4-drill bit, 5-quick joint, 6-orifice pipe, 7-anchor agent, 8-concrete, 9-shallow hole, 10-slurry , 11-grouting hose, 12-slurry valve, 13-pressure relief valve, 14-slurry diffusion area, 15-deep hole, 16-sealed concrete.

Detailed ways:

An embodiment of the present invention will be further described below in conjunction with accompanying drawing:

The deep and shallow hole and high and low pressure coupling grouting process of the present invention:

A, start drilling rig 1, make the drilling rod 2 that has drill bit 4 drill a shallow hole 9 in surrounding rock body 3, drilling depth is determined according to the loose circle size and surrounding rock fragmentation degree, and described shallow hole 9 depth is 2000mm~3000mm, the shallow hole diameter is 40mm~60mm;

b. Insert the orifice pipe 6 into the shallow hole 9, and seal the hole, fix it with anchoring agent 7, and seal the hole with silk floss or rapid hardening cement, etc., the length of the orifice pipe 6 is 500mm~1000mm, and the diameter is 30mm~ 40mm, made of steel pipe, the exposed end of the orifice pipe 6 is connected to the grout valve 12, the pressure relief valve 13 and the quick connector 5, and the grout valve 12 is connected to the grouting hose 11;

c. After the orifice pipe 6 is installed, the rock surface is sprayed again, and the rock surface around the orifice is sprayed with concrete 8, so that the rock surface around the orifice forms a sealing layer for the orifice pipe 6; the sprayed concrete The strength grade of 8 is C25~C30, the thickness of the resprayed concrete is 30mm~50mm, and the exposed length of the orifice pipe 6 is not less than 30 mm, so as to facilitate grouting reinforcement in the later stage;

d. Perform low-pressure shallow hole grouting, connect the grouting device grouting hose 11 and the grouting valve 12, then start the grouting pump, open the grouting valve 12, and carry out low-pressure shallow holes through the orifice pipe 6 into the shallow hole 9 Grouting, the grouting pressure is controlled at 2MPa~3MPa, so that the grout fully penetrates into the surrounding rock mass 3 around the shallow hole 9; the grout 10 is diffused to fill the cracks, forming a grout diffusion area 14, and achieving the purpose of reinforcing the surrounding rock mass 3, The low-pressure shallow hole grouting slurry adopts cement slurry or cement-water glass composite slurry;

e. After the low-pressure shallow hole grouting is completed, after the grout has solidified for 3 to 7 days, remove the grouting pipe, use the drill bit to sweep the hole inward through the orifice pipe 6, and change the shallow hole 9 into a deep hole 15, and the deep hole The depth of 15 is determined according to the size of the surrounding rock loose circle and the degree of fragmentation of the surrounding rock; the depth of the deep hole 15 is 5000mm ~ 6000mm, and the borehole diameter is 20mm ~ 30mm;

f. After the deep hole grouting is completed, drill back, connect the grouting pipe, and carry out high-pressure deep hole grouting with the grout pressure controlled at 3MPa~5MPa into the deep hole 15 through the orifice pipe 6, so that the grout can fully penetrate into the surroundings of the deep hole 15. In the surrounding rock body 3, it is coupled with the grout around the shallow hole 9 to form a grout diffusion area 14. The grouting material is mainly dilute cement grout. If the cracks in the surrounding rock are small, use ultra-fine cement or chemical grout;

g. After 3 to 7 days after the grouting of the deep hole 15 is completed, the grouting pipe is removed, and the surrounding rock is re-sprayed with concrete 8. The thickness of the re-sprayed concrete is 30mm~50mm, and the surrounding rock is sealed to prevent the injection hole. The slurry seeps out, and the exposed length of the orifice pipe 6 is guaranteed to be no less than 30 mm.

The above description is only a preferred embodiment of the present invention, and it should be pointed out that for skilled workers in this technical field, without departing from the technical principle of the present invention, some improvements or replacements can also be made, and these improvements or replacements can also be made. It should be regarded as the protection scope of the present invention.

Claims (6)

1. a depth hole and high-low pressure coupling grouting process, is characterized in that, comprises following steps:

A, at first bore a shallow bore hole (9) in country rock body (3);

B, at shallow bore hole (9) interpolation man-hole opening pipe (6), and carry out sealing of hole, orifice tube (6) exposed junction is connected with Grouting Pipe;

C, the scar sprayed mortar (8) around to the aperture make the scar around the aperture form confining bed to orifice tube (6);

D, open the slip casting by-pass valve control, carry out the low pressure Shallow hole grouting that pressure is controlled at 2MPa ~ 3MPa by orifice tube (6) in shallow bore hole (9), slurries are fully penetrated in shallow bore hole (9) Rock And Soil (14) on every side;

After e, low pressure Shallow hole grouting are completed, after slurries solidify 3 ~ 7 days, lay down Grouting Pipe, adopt drill bit inwardly to carry out cleaning bottom of hole through orifice tube (6), shallow bore hole (9) is changed into a deep hole (15), and the degree of depth of deep hole (15) is determined according to wall rock loosening ring size and rock crusher degree;

F, deep hole grouting are completed and are retreated brill, connect Grouting Pipe, carry out the high pressure deep hole grouting that slurries pressure is controlled at 3MPa ~ 5MPa by orifice tube (6) in deep hole (15), slurries are fully penetrated in deep hole (15) Rock And Soil (14) on every side, and be coupled with shallow bore hole (9) slurries on every side, reinforce Rock And Soil (14), injecting paste material is take cement water grout liquid as main, if wall-rock crack is less, adopt superfine cement or chemical grout;

After g, deep hole (15) slip casting are completed 3 ~ 7 days, lay down Grouting Pipe, country rock is carried out again pneumatically placed concrete (8) again, the thickness of multiple pneumatically placed concrete is 30mm ~ 50mm, country rock is sealed, prevent that the slurries in injection hole from oozing out, and guarantee that the protruded length of orifice tube (6) is no less than 30 mm.

Depth hole according to claim 1 and high-low pressure the coupling grouting process, it is characterized in that: described shallow bore hole (9) degree of depth is 2000mm ~ 3000mm, and the shallow bore hole diameter is 40mm ~ 60mm.

Depth hole according to claim 1 and high-low pressure the coupling grouting process, it is characterized in that: described orifice tube (6) length is 500mm ~ 1000mm, and diameter is 30mm ~ 40mm.

Depth hole according to claim 1 and high-low pressure the coupling grouting process, it is characterized in that: the strength grade of described sprayed mortar (8) is C25 ~ C30.

5. depth hole according to claim 1 and high-low pressure coupling grouting process, is characterized in that: described low pressure Shallow hole grouting slurries employing cement grout or cement-sodium silicate compound slurry.

Depth hole according to claim 1 and high-low pressure the coupling grouting process, it is characterized in that: the degree of depth of described deep hole (15) is 5000mm ~ 6000mm, bore diameter is 20mm ~ 30mm.

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