阅读说明：本技术 封闭不良钻孔井下分层加固方法 (Underground layering reinforcing method for badly-closed drill hole ) 是由 孔皖军 国伟 薛悟强 常成林 雷锋 于 2020-08-05 设计创作，主要内容包括：本发明公开封闭不良钻孔井下分层加固方法,涉及矿井治理技术领域,(1)布设探查钻孔；(2)对施工后的第一探查钻孔、第二探查钻孔和第三探查钻孔依次进行注浆封堵。本发明的有益效果在于：采用本发明中的井下分层加固方法,可以保证隔水层的厚度,封住隔水层之间的承压水,同时采用高密度布孔,分层次注浆加固的方式,在封闭不良钻孔煤底板及奥灰层形成隔水帷幕,阻断了封闭不良钻孔沟通的导水通道,在井下防治钻孔水,避免了因地面环境影响无法对钻孔井下地面启封的情况,为终孔位于奥灰中的封闭不良钻孔的治理提供了有效方法。(The invention discloses an underground layered strengthening method for a poorly sealed borehole, which relates to the technical field of mine treatment, and comprises the following steps of (1) laying exploration boreholes; (2) and sequentially carrying out grouting plugging on the first exploration drilling hole, the second exploration drilling hole and the third exploration drilling hole after construction. The invention has the beneficial effects that: by adopting the underground layered reinforcement method, the thickness of the water-resisting layers can be ensured, the confined water between the water-resisting layers can be sealed, meanwhile, a high-density hole distribution and layered grouting reinforcement mode is adopted, a water-resisting curtain is formed on the coal bottom plate and the lime layer of the sealed and badly drilled holes, a water guide channel communicated with the sealed and badly drilled holes is blocked, the water of the drilled holes is prevented and controlled underground, the condition that the underground ground of the drilled holes cannot be unsealed due to the influence of the ground environment is avoided, and an effective method is provided for the treatment of the sealed and badly drilled holes with final holes in the lime.)

1. A downhole layered reinforcing method for a poorly-sealed borehole is characterized by comprising the following steps: the method comprises the following steps:

(1) laying a probing borehole: the exploration drilling holes are distributed in groups, a horizontal plane in front of the roadway is in a fan shape, the coverage range of the final holes of the exploration drilling holes takes the closed bad drilling holes as the circle centers, and the radius is not less than 20 m;

exploring a coal bottom plate layer, wherein the coal bottom plate layer is positioned above a transportation crossheading, and when the distance between the transportation crossheading and a sealed and bad borehole is not less than 30m, constructing a plurality of first exploration boreholes at the head of an underground roadway; constructing a plurality of second exploration drill holes at positions of the underground roadway with the head-on and back-off greater than 30m, wherein the final hole positions of the first exploration drill holes and the second exploration drill holes are coal bottom plates;

exploring an Ordovician limestone layer, wherein the Ordovician limestone layer is positioned below a coal bed plate layer, a plurality of third exploration drill holes are constructed in a transportation crossheading roadway, the exploration range is that the closed poor drill holes are used as the circle center, and the final hole layer of each third exploration drill hole enters the Ordovician limestone with the vertical distance of 2 m;

(2) and sequentially carrying out grouting plugging on the first exploration drilling hole, the second exploration drilling hole and the third exploration drilling hole after construction.

2. The method of claim 1, wherein the method comprises: and (2) probing the position of the final hole of the drilled hole in the step (1) to meet the horizontal plane distance of 3 m.

3. The method of claim 1, wherein the method comprises: adopting a first drilling tool to drill a hole towards the exploration drilling in a roadway for primary hole opening, feeding a first sleeve into the hole, wherein the outer diameter of the first sleeve is smaller than the diameter of the primary hole opening, sealing by injecting a sealing agent, after a pressure-bearing experiment is qualified, adopting a second drilling tool to open a hole, the depth of the secondary hole opening is larger than that of the primary hole opening, lowering a second sleeve, the outer diameter of the second sleeve is smaller than that of the secondary hole opening, sealing by injecting the sealing agent, after the pressure-bearing experiment is qualified, adopting a third drilling tool to open the hole to the final hole depth, and then injecting the sealing agent for sealing.

4. The method of claim 3, wherein the method comprises: adopting a phi 168mm drill bit to open a hole to 6m, descending a phi 146mm first sleeve to 5.5m, injecting a sealing agent for sealing, adopting a phi 127mm drill bit to open a hole to 12m after the first pressure-bearing experiment is qualified, descending a phi 108mm second sleeve to 11m, injecting a sealing agent for sealing, adopting a phi 75mm drill bit to open a hole to the final hole depth after the second pressure-bearing experiment is qualified, wherein the aperture of the final hole is 75mm, and then injecting a sealing agent for sealing.

5. The method of claim 3, wherein the method comprises: and (3) drilling a hole by adopting a phi 133mm drill bit, setting a phi 146mm third sleeve 11m, injecting a sealing agent for sealing, then sealing the hole by using a phi 95mm drill bit through the bottom of the pipe by 0.5m, and injecting a sealing agent for sealing until the pressure-bearing test is qualified.

6. The method of claim 5, wherein the method comprises: be equipped with the ring flange between the tip of first sheathed tube tip and second sleeve, the ring flange deviates from the sheathed tube one end of second and is equipped with the drill way sleeve pipe, the sheathed tube one end of drill way can be dismantled with the tip of second sleeve and be connected, the sheathed tube other end of drill way is equipped with first gate valve, the sheathed tube lateral wall of drill way is equipped with the pressure measurement gate valve, be equipped with the manometer on the pressure measurement gate valve.

7. The method of claim 1, wherein the method comprises: the number of first probe boreholes is at least 8.

8. The method of claim 1, wherein the method comprises: the number of second probe boreholes is at least 7.

9. The method of claim 1, wherein the method comprises: the number of third probe boreholes is at least 12.

10. The method of claim 1, wherein the method comprises: the double-grout is mainly prepared from cement paste and water glass, the volume ratio of the cement paste to the water glass is 1: 1-1: 0.6, and the water cement ratio in the cement paste is 1: 1-3: 1.

Technical Field

The invention relates to the technical field of mine treatment, in particular to a downhole layered reinforcing method for a poorly-closed borehole.

Background

Along with the increasing of the coal mining depth, the change of the mining mode, the conditions generated by coal mine water damage and the mode generated by water damage are greatly changed, wherein the sealed bad drill hole is an important factor inducing the occurrence of the coal mine water damage and is a hidden danger threatening the safety production of the coal mine, the sealed bad drill hole is divided into two types, one type is that no sleeve is arranged in the drill hole and the cement slurry which is not sealed in the drill hole is fully filled and consolidated, and the other type is that the sleeve is arranged in the drill hole but the annular gap between the outer wall of the sleeve and the rock stratum of the drill hole is not fully consolidated and filled by the cement slurry.

The sealed poor drilled holes become water guide channels for conducting the upper aquifer and the lower aquifer, which are caused by human factors, the water inrush disaster of the bottom plate is a common mine disaster, and particularly, the sealed poor drilled holes with the final holes positioned in the Ordovician limestone become channels for directly guiding the water of the Ordovician limestone, so that the safety hazard to the mine is great. The patent with publication number CN105114029A discloses a water plugging method for a poorly sealed borehole in a mine tunnel, which comprises the steps of grouting and water plugging the poorly sealed borehole after the poorly sealed borehole is uncovered in the process of tunneling the mine tunnel. However, partially-closed bad drilling orifices are damaged, orifice identification cannot be found, ground unsealing cannot be performed, and the method has serious potential safety hazard and needs reinforcement before being exposed.

Disclosure of Invention

The technical problem to be solved by the invention is that when the hole opening of the sealed bad drill hole with the final hole in the Ordovician limestone is damaged, the ground cannot find the hole opening mark, the ground cannot be unsealed, the ground has serious potential safety hazard, reinforcement is needed before the disclosure, and the underground layered reinforcement method for the sealed bad drill hole is provided.

The invention solves the technical problems through the following technical means:

the underground layered reinforcing method for the poorly closed borehole comprises the following steps:

(1) laying a probing borehole: the exploration drilling holes are distributed in groups, the horizontal plane in front of the roadway is in a fan shape, the horizontal plane horizontal distance of the final hole positions of the exploration drilling holes is 3m, the coverage range of the final holes of the exploration drilling holes takes the sealed bad drilling holes as the circle centers, and the radius is not less than 20 m;

exploring a coal bottom plate layer, wherein the coal bottom plate layer is positioned above a transportation crossheading, and when the distance between the transportation crossheading and a sealed and bad borehole is not less than 30m, constructing a plurality of first exploration boreholes at the head of an underground roadway; constructing a plurality of second exploration drill holes at positions 45m behind the head-on and back-off positions of the underground roadway, wherein the final hole positions of the first exploration drill holes and the second exploration drill holes are coal floor layers;

exploring an Ordovician limestone layer, wherein the Ordovician limestone layer is positioned below a coal bed plate layer, a plurality of third exploration drill holes are constructed in a transportation crossheading roadway, the exploration range is that the closed poor drill holes are used as the circle center, and the final hole layer of each third exploration drill hole enters the Ordovician limestone with the vertical distance of 2 m;

(2) and sequentially carrying out grouting plugging on the first exploration drilling hole, the second exploration drilling hole and the third exploration drilling hole after construction.

Has the advantages that: by adopting the underground layered reinforcement method, the thickness of the water-resisting layers can be ensured, the confined water between the water-resisting layers can be sealed, meanwhile, a high-density hole distribution and layered grouting reinforcement mode is adopted, a water-resisting curtain is formed on the coal bottom plate of the sealed bad drilled holes and the lime layer, a water guide channel communicated with the sealed bad drilled holes is blocked, the drilled water is prevented and treated underground, the condition that the underground ground of the drilled holes cannot be unsealed due to the influence of the ground environment is avoided, the reinforcement is carried out before the sealed bad drilled holes are exposed, and an effective method is provided for the treatment of the sealed bad drilled holes with final holes in the lime.

Preferably, the final hole position of the exploration drilling hole in the step (1) meets the horizontal plane flat distance of 3 m.

Preferably, a first drilling tool is adopted to drill a hole towards the exploration drilling hole in the roadway for the first time, a first sleeve is sent into the hole, the outer diameter of the first sleeve is smaller than the diameter of the first opening, sealing is conducted by injecting a sealing agent, after a pressure-bearing experiment is qualified, a second drilling tool is adopted to drill the hole, the depth of the second opening is larger than the depth of the first opening, a second sleeve is put down, the outer diameter of the second sleeve is smaller than the diameter of the second opening, sealing is conducted by injecting the sealing agent, after the pressure-bearing experiment is qualified, a third drilling tool is adopted to drill the hole to the final hole depth, and then the sealing agent is injected for sealing.

Preferably, the number of first probe boreholes is at least 8.

Preferably, the number of second probe boreholes is at least 7.

Preferably, the number of said third probe boreholes is at least 12.

Preferably, a drill bit with the diameter of 168mm is adopted for drilling to 6m, a first sleeve with the diameter of 146mm is arranged below the drill bit to 5.5m, the sealing agent is injected for sealing, after the first pressure-bearing test is qualified, the drill bit with the diameter of 127mm is adopted for drilling to 12m, a second sleeve with the diameter of 108mm is arranged below the drill bit to 11m, the sealing agent is injected for sealing, after the second pressure-bearing test is qualified, the drill bit with the diameter of 75mm is adopted for drilling to the final hole depth, the aperture of the final hole is 75mm, and then the sealing agent is injected for sealing.

Preferably, a drill bit with the diameter of 133mm is used for drilling, a third sleeve with the diameter of 146mm is arranged at the lower part of the third sleeve by 11m, a sealing agent is injected for sealing, then the drill bit with the diameter of 95mm is used for sealing and passing through the bottom of the pipe by 0.5m, and the sealing agent is injected for sealing until the pressure-bearing test is qualified.

Preferably, be equipped with the ring flange between the tip of first sheathed tube tip and second sleeve, the ring flange deviates from the sheathed tube one end of second and is equipped with the drill way sleeve pipe, the sheathed tube one end of drill way can be dismantled with the tip of second sleeve and be connected, the sheathed tube other end of drill way is equipped with first gate valve, the sheathed tube lateral wall of drill way is equipped with the pressure measurement gate valve, be equipped with the manometer on the pressure measurement gate valve.

Preferably, the double grout is mainly prepared from cement paste and water glass, the volume ratio of the cement paste to the water glass is 1: 1-1: 0.6, and the water cement ratio in the cement paste is 1: 1-3: 1.

Preferably, the baume degree of the water glass is 35-40.

Preferably, the first pressure-bearing test comprises the following steps: and (3) after the first sleeve is sealed for 8 hours, injecting water into the first sleeve, and measuring the pressure of an orifice to be 3Mpa for 30 minutes by a pressure gauge, wherein the orifice and the periphery are qualified without water leakage.

Preferably, the second pressure-bearing test comprises the following steps: and (4) after the second sleeve is sealed for 8 hours, injecting water into the second sleeve, and measuring the pressure of an orifice to be 5Mpa for 30 minutes by a pressure gauge, wherein the orifice and the periphery are qualified without water leakage.

The invention has the advantages that: by adopting the underground layered reinforcement method, the thickness of the water-resisting layers can be ensured, the confined water between the water-resisting layers can be sealed, meanwhile, a high-density hole distribution and layered grouting reinforcement mode is adopted, a water-resisting curtain is formed on the coal bottom plate and the lime layer of the sealed and badly drilled holes, a water guide channel communicated with the sealed and badly drilled holes is blocked, the water of the drilled holes is prevented and controlled underground, the condition that the underground ground of the drilled holes cannot be unsealed due to the influence of the ground environment is avoided, and an effective method is provided for the treatment of the sealed and badly drilled holes with final holes in the lime.

Drawings

Fig. 1 is a plan view of the distribution of a first exploratory borehole and a second exploratory borehole of a 61102 transportation gate D12 in embodiment 1 of the present invention;

fig. 2 is a distribution cross-sectional view of a first exploratory borehole and a second exploratory borehole of the 61102 transportation gate D12 in embodiment 1 of the present invention;

FIG. 3 is a diagram of the hole position arrangement of the first exploratory drill hole of the 61102 transportation gate D12 in example 1 of the present invention;

FIG. 4 is a plan view of the distribution of a third exploration hole of the 61102 transportation gate D12 in embodiment 1 of the present invention;

FIG. 5 is a cross-sectional view of the distribution of a third exploration hole of the 61102 transportation gate D12 in embodiment 1 of the invention;

FIG. 6 is a diagram of the hole position arrangement of a third exploratory drill hole in a part D12 of the 61102 transportation gate in the embodiment 1 of the present invention;

FIG. 7 is a diagram of the hole position arrangement of a third exploratory drill hole in a part D12 of the 61102 transportation gate in the embodiment 1 of the present invention;

FIG. 8 is a schematic view of a casing drilling structure in embodiment 2 of the present invention;

FIG. 9 is a schematic view of a casing drilling structure in embodiment 3 of the present invention;

in the figure: sealing the poor drilled hole 1; a first sleeve 2; a second sleeve 3; a non-standard flange disk 4; an orifice sleeve 5; a first gate valve 6; a pressure measuring gate valve 7; a pressure gauge 8; a drill site 9; a third sleeve 11.

A represents a diameter of 168 mm; b represents a diameter of phi 146 mm; c represents a diameter of 127 mm; d represents a phi 128mm aperture; e represents a phi 75mm aperture; f represents a phi 133mm aperture; g represents a diameter of phi 108 mm.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Test materials, reagents and the like used in the following examples are commercially available unless otherwise specified.