CN108729438B - Treatment method for karst area channel - Google Patents
Treatment method for karst area channel Download PDFInfo
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- CN108729438B CN108729438B CN201810523221.5A CN201810523221A CN108729438B CN 108729438 B CN108729438 B CN 108729438B CN 201810523221 A CN201810523221 A CN 201810523221A CN 108729438 B CN108729438 B CN 108729438B
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- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D3/00—Improving or preserving soil or rock, e.g. preserving permafrost soil
- E02D3/12—Consolidating by placing solidifying or pore-filling substances in the soil
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- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D19/00—Keeping dry foundation sites or other areas in the ground
- E02D19/06—Restraining of underground water
- E02D19/12—Restraining of underground water by damming or interrupting the passage of underground water
- E02D19/16—Restraining of underground water by damming or interrupting the passage of underground water by placing or applying sealing substances
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- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D19/00—Keeping dry foundation sites or other areas in the ground
- E02D19/06—Restraining of underground water
- E02D19/12—Restraining of underground water by damming or interrupting the passage of underground water
- E02D19/18—Restraining of underground water by damming or interrupting the passage of underground water by making use of sealing aprons, e.g. diaphragms made from bituminous or clay material
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- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D3/00—Improving or preserving soil or rock, e.g. preserving permafrost soil
- E02D3/02—Improving by compacting
- E02D3/10—Improving by compacting by watering, draining, de-aerating or blasting, e.g. by installing sand or wick drains
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- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Structural Engineering (AREA)
- Environmental & Geological Engineering (AREA)
- Hydrology & Water Resources (AREA)
- Mining & Mineral Resources (AREA)
- Paleontology (AREA)
- Civil Engineering (AREA)
- General Engineering & Computer Science (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Agronomy & Crop Science (AREA)
- Soil Sciences (AREA)
- Consolidation Of Soil By Introduction Of Solidifying Substances Into Soil (AREA)
Abstract
The invention discloses a treatment method of a karst area channel, which comprises the following steps: probing the position of the karst channel by using a low-frequency vibration detector; distributing holes and drilling according to the position of the detected karst channel; filling pebbles in the front hole and the rear hole of the curtain; placing grouting pipes in the front hole and the rear hole of the curtain and pouring mortar; injecting paste into the curtain line hole by using a high-pressure pump; and finally, injecting cement slurry into the upper hole of the curtain line, and controlling the grouting pressure to be 0.5-1 MPa until no slurry or water overflows at the water leakage position of the karst cave, so as to finish the treatment of the channel in the karst region. The invention can quickly and accurately probe the channel position by using the low-frequency vibration technology, optimize the hole distribution and backfill and slip-cast the holes, and perform water plugging and seepage-proofing treatment on the channel in the karst region under the condition of flowing water, wherein the water burst plugging rate can reach more than 95 percent, and the rock stratum water permeability can be reduced to be within 5 Lu.
Description
Technical Field
The invention belongs to a construction method of constructional engineering, and particularly relates to a method for quickly exploring, backfilling and grouting a karst area channel under a flowing water condition.
Background
The total area of the carbonate rock stratum in China is 346 ten thousand square kilometers, which occupies 1/3 of the total area of the national soil, and various forms of karsts are formed due to the corrosion action generated by the surface water and the underground water, so that the anti-permeability and damage capability of the rocks is greatly reduced, and the safety of buildings is directly influenced. Grouting is used as an important means for anti-seepage treatment of a karst area, is widely applied to various engineering constructions, and has mature industrial technical experience. However, grouting a strong karst area under the condition of flowing water is always a difficult problem that the construction cost is uncontrollable and the technical difficulty is the greatest. How to control the effective grouting amount in the rock stratum crack within the thickness of the designed curtain to reduce the ineffective diffusion of the grout, improve the construction efficiency, reduce the cost of the grout and better reduce the construction cost is the development direction of the grouting engineering technology.
The method for rapidly and accurately detecting the position of the underground water seepage channel is the primary condition for controlling the channel, the existing mature methods in detection comprise a direct current resistivity method, a natural electric field method, a transient electromagnetic method, a ground penetrating radar method, an elastic wave method, a temperature field method, an isotope tracing method and the like, instruments adopted by the methods are very expensive, the detected position of the underground water seepage channel is inaccurate, and the deviation reaches more than 10 meters; in the prior art, holes are drilled at the position of a karst cave of a curtain line, and cement grout is injected for plugging after aggregate is filled, so that the method can cause the problems of large karst cave channel, high water flow speed and the like, the aggregate and the grout are washed away, the grout is inefficiently diffused, the construction efficiency is low, the cost is increased, and a water plugging curtain can not be formed seriously; and the grouting is usually carried out by adopting methods of granular material filling, cement-water glass double-liquid grouting, quick-setting paste grouting, high-water material grouting, cloth bag grouting and the like, and the methods have the problems of high construction cost, long construction period, difficult guarantee of construction effect and the like.
Disclosure of Invention
The technical problem to be solved by the invention is to overcome the defects and defects mentioned in the background technology, and provide a method for quickly exploring, backfilling and grouting a karst area channel under the condition of flowing water, in particular to a method for treating gushing water of an excavated large open-pit mine in a strong karst development area or a reservoir in the strong karst development area.
In order to solve the technical problems, the technical scheme provided by the invention is as follows:
a treatment method of a karst area channel comprises the following steps:
(1) probing the position of the karst channel by using a low-frequency vibration detector; when underground water flows through an underground passage, 1-8Hz low-frequency vibration can be generated, and the generated low-frequency vibration can cause the vibration of a magnet inserted in a magnetic suspension detector on the ground, so that magnetic lines of force are cut, current and voltage difference are generated, and after amplification and filtering of a plurality of stages by an amplifier, the current and voltage difference are displayed on a display, and the position of a karst cave passage is further judged; the karst cave position is probed by using the low-frequency vibration generated when water flow passes through the karst cave, so that the detection frequency bandwidth is increased, the detection sensitivity is improved, and the karst cave position is easier to detect;
(2) distributing holes and drilling according to the position of the detected karst channel;
(3) filling pebbles in the front hole and the rear hole of the curtain; pebbles are quickly filled by using a stone throwing machine, the water flow speed in the channel is reduced, and the large water permeable channel is changed into a small water permeable channel;
(4) placing grouting pipes in the front hole and the rear hole of the curtain and pouring mortar; further reducing the water flow speed to change the moving water into the relatively still water;
(5) injecting paste slurry into the upper hole of the curtain line by using a high-pressure pump to form a water-plugging curtain with a certain thickness; compared with the method adopting low-pressure grouting of cement slurry, the method can effectively reduce the diffusion and loss of the slurry;
(6) and finally, injecting cement slurry into the upper hole of the curtain line, and controlling the grouting pressure to be 0.5-1 MPa until no slurry or water is gushed out at the water leakage position of the channel (filling the gap of the curtain), thereby finishing the treatment of the channel in the karst area.
In the treatment method, preferably, in the step (2), the hole distribution means that drilling is respectively performed before, after and on the screen of the karst passage passing through the curtain line by using a drilling machine, and during the drilling process, when a sudden drill rod falls obviously or water or slurry gushes out under ventilation pressure, the part is a karst cave.
Preferably, in the treatment method, in the step (2), a drill hole with the diameter of 75-110 mm is drilled in the drilling process, the diameter of the final hole is not less than 75mm, and a protective sleeve is adopted for follow-up after the hole is formed.
In the treatment method, preferably, in the step (4), the inner diameter of the grouting pipe hole is not less than 55mm, and the wall thickness is not less than 5 mm.
Preferably, in the treatment method, in the step (4), mortar is poured under the pressure of 0.5-2 MPa, and the mortar is self-leveling mortar.
Preferably, in the treatment method, in the step (5), the grouting pressure is controlled to be 2-10 MPa, and the treatment is finished when the grouting pressure is stabilized to be 2-3 MPa.
Preferably, in the treatment method, in the step (5), the paste is clay cement paste with early strength and erosion resistance, and the paste mainly comprises cement, sand, stone, clay, water and an additive in the mass ratio of 50 to (50-150) to (0-300) to (50-100) to (80-250) to (0.1-0.3).
The invention quickly finds the karst cave channel by the low-frequency vibration technology, optimizes the hole distribution, respectively drills holes at the front position and the rear position of the karst cave channel passing through the curtain line, adopts a stone thrower to quickly fill cobbles, reduces the water flow speed in the channel, and changes the large water permeable channel into the small water permeable channel; and filling the holes on the curtain line with paste slurry or mortar at high pressure, and compared with the method of filling cement slurry at low pressure, the method can effectively reduce the diffusion and loss of the slurry, thereby effectively forming a water-blocking curtain with a certain thickness, and finally filling the cement slurry into the gaps of the curtain with the thickness to prevent water seepage.
Compared with the prior art, the invention has the advantages that:
(1) the invention can quickly and accurately probe the channel position by using the low-frequency vibration technology, optimizes the hole distribution and combines a proper backfill grouting mode, so that the invention has obvious superiority in the aspects of construction economy, convenience, construction effect, environmental protection performance and the like; meanwhile, water plugging and seepage-proofing treatment is carried out on the karst area channel under the condition of flowing water, the water burst plugging rate can reach more than 95%, and the rock stratum water permeability can be reduced to be within 5 Lu.
(2) The invention solves the technical problems of high flow rate of underground water, large karst cavity, complex karst pipeline, slow channel search, slow grouting speed, high technical difficulty and the like when grouting is carried out in a karst channel development area under the condition of flowing water.
Detailed Description
In order to facilitate an understanding of the present invention, the present invention will be described more fully and in detail with reference to the preferred embodiments, but the scope of the present invention is not limited to the specific embodiments below.
Unless otherwise defined, all terms of art used hereinafter have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the present invention.
Unless otherwise specifically stated, various raw materials, reagents, instruments, equipment and the like used in the present invention are commercially available or can be prepared by existing methods.
Example 1:
lei Gong Miao area limestone mine, near the fieldThe stratum is a fourth series loose accumulation layer and Ordovician limestone, the ground is mainly provided with faults of F2, F1-1, F1-2, F1-3 and the like, the maximum exploration karst cave height is 23.5m, the distribution width reaches 30m, the maximum daily water discharge amount can reach 90000m3And d, simultaneously, secondary geological disasters nearby the site are also continuously generated. In order to ensure normal mining of ores, the underground water level around a mining area reaches the normal water level, geological disasters caused by pumping water around the site are reduced or eliminated, and water burst treatment needs to be carried out on the mining area.
The method for water plugging treatment comprises the following specific steps:
(1) firstly, detecting the accurate position of a karst channel by using a low-frequency vibration detector (when underground water flows through an underground channel, low-frequency vibration is generated, the low-frequency vibration causes the magnet inserted in the detector on the ground to vibrate, magnetic lines of force are cut to generate current and voltage difference, and data are displayed on a display screen after the current and the voltage are amplified by an amplifier);
(2) respectively testing holes in front of a screen, behind the screen and on the screen in a karst passage passing through a curtain line by a drilling machine and drilling; in the hole testing process, when the drill rod falls obviously suddenly or water or slurry gushes out during ventilation pressure, the part is a karst cave, and the depth of the karst cave is further determined; drilling a hole with the diameter of 91mm in the drilling process, wherein the diameter of a final hole is not less than 75mm, and following by using a protective sleeve after hole forming;
(3) pebbles with the diameter of 15-40mm are thrown in the front holes and the rear holes of the curtain line curtain by a stone throwing machine, so that a karst channel is quickly filled, and the water flow speed in the channel is reduced;
(4) then, grouting pipes (the inner diameter of each grouting pipe hole is not less than 55mm, the wall thickness is not less than 5mm) are arranged in front of the curtain line curtain and in the rear of the curtain line curtain, grouting pipelines are connected, grouting pumps, pressure gauges, valves and the like are connected, self-leveling mortar is injected under the pressure of about 1MPa, the flow rate is further reduced, and the flowing water in the channel is changed into relative still water;
(5) injecting paste with the mass ratio of cement, sand, stone, clay, water and additive being 50: 50-150: 0-300: 50-100: 80-250: 0.1-0.3 into the hole on the curtain line by using a high-pressure pump, wherein the grouting pressure is about 8MPa, and the paste injection is stopped when the pressure is stabilized at 2-3 MPa; finally, cement slurry is injected, the grouting pressure is controlled to be about 1MPa until no slurry and water at the water leakage position of the channel gushes out, the karst channel is completely blocked, and a certain curtain thickness is formed; and then the next channel is subjected to water plugging treatment by adopting the same method.
After the construction is finished by adopting the method, the underground water level elevation outside the curtain line is increased from +25m to + 37-38 m to reach the underground water level before the mine pit is not excavated; the water inflow is from 90000m3The d is reduced to 2000m3D, meeting the contract requirement of less than 10000mm3And d. After half a year of observation and subsequent ore mining, the water inflow in the pit has not obviously changed.
Example 2:
the water content of soil body at the bank section of the south water crossing power station is high, the flooding phenomenon is obvious, seepage exists at a plurality of bank bodies and slope feet, a plurality of piping and sediment are entrained in the farmland behind the bank, and the water inflow is continuously increased; the clear water leakage phenomenon occurs at a plurality of positions, and the dykes at the leakage positions have collapsed pits with the depth of 1.5m and the diameter of about 1.5m, thus seriously endangering the safety and the stability of the dykes. For the safe operation of the embankment, an effective plugging treatment must be performed.
The method for water plugging treatment comprises the following specific steps:
(1) firstly, detecting the accurate position of a water leakage channel by using a low-frequency vibration detector (when underground water flows through an underground channel, low-frequency vibration is generated, the low-frequency vibration causes the magnet inserted in the detector on the ground to vibrate, magnetic lines of force are cut to generate current and voltage difference, and data are displayed on a display screen after the current and the voltage are amplified by an amplifier);
(2) respectively testing holes in front of a curtain, behind the curtain and on the curtain line through a water leakage channel of the curtain line by a drilling machine and drilling; in the hole testing process, when the drill rod falls obviously suddenly or water or slurry gushes out during ventilation pressure, the part is a karst cave, and the depth of the karst cave is further determined; drilling a hole with the diameter of 91mm in the drilling process, wherein the diameter of a final hole is not less than 75mm, and following by using a protective sleeve after hole forming;
(3) pebbles with the diameter of 10-30mm are thrown by a stone throwing machine in front of a curtain line curtain and in a rear hole of the curtain line curtain, a water leakage channel is quickly filled, and the water flow speed in the channel is reduced;
(4) then, grouting pipes (the inner diameter of each grouting pipe hole is not less than 55mm, the wall thickness is not less than 5mm) are arranged in front of the curtain line curtain and in the rear of the curtain line curtain, grouting pipelines are connected, grouting pumps, pressure gauges, valves and the like are connected, self-leveling mortar is injected under the pressure of about 1MPa, the flow rate is further reduced, and the flowing water in the channel is changed into relative still water;
(5) injecting paste with the mass ratio of cement, sand, stone, clay, water and additive being 50: 50-150: 0-100: 100-300: 80-250: 0.1-0.3 into the hole on the curtain line by using a high-pressure pump, wherein the grouting pressure is about 8MPa, and the paste injection is stopped when the pressure is stabilized at 2-3 MPa; and finally, injecting cement slurry, and controlling the grouting pressure to be about 1MPa until no slurry and water flow out from the water leakage position of the channel, so that the channel is completely blocked and a certain curtain thickness is formed.
After the engineering is finished, water injection tests are carried out, and the results show that the permeability coefficients of the water injection tests are less than 1.0 multiplied by 10-4cm/s and water permeability in water pressure test<5Lu, meets the requirements of the scheme, detects more serous fluid stones in the hole core, has good cementation and better curtain grouting water plugging effect.
Claims (6)
1. A treatment method for a karst area channel is characterized by comprising the following steps:
(1) probing the position of the karst channel by using a low-frequency vibration detector;
(2) distributing holes and drilling according to the position of the detected karst channel; the hole distribution means that drilling is respectively carried out on the front part, the back part and the curtain line of the karst channel curtain passing through the curtain line by using a drilling machine;
(3) pebbles are quickly filled in the front hole and the rear hole of the curtain by using a stone thrower, so that the water flow speed in the channel is reduced, and the large water permeable channel is changed into a small water permeable channel;
(4) grouting pipes are arranged in the front hole and the rear hole of the curtain, mortar is poured into the grouting pipes, and the flowing water is changed into relative still water;
(5) injecting paste slurry into the holes on the curtain line by using a high-pressure pump to form a water plugging curtain;
(6) and finally, injecting cement slurry into the upper hole of the curtain line, and controlling the grouting pressure to be 0.5-1 MPa until no slurry or water is gushed out at the water leakage position of the channel, so as to finish the treatment of the channel in the karst area.
2. The treatment method according to claim 1, wherein in the step (2), a drill hole with the diameter of 75-110 mm is drilled in the drilling process, the diameter of the final hole is not less than 75mm, and a protective sleeve is used for follow-up after the hole is formed.
3. The remediation method of claim 1 wherein in step (4) the bore diameter of the slip casting pipe is no less than 55mm and the wall thickness is no less than 5 mm.
4. The treatment method according to claim 1, wherein in the step (4), mortar is poured under a pressure of 0.5 to 2MPa, and the mortar is self-leveling mortar.
5. The treatment method according to claim 1, wherein in the step (5), the grouting pressure is controlled to be 2-10 MPa, and the grouting is finished when the grouting pressure is stabilized to be 2-3 MPa.
6. The treatment method according to claim 1, wherein in the step (5), the paste is clay cement paste with early strength and erosion resistance, and the paste mainly comprises cement, sand, stone, clay, water and an additive in the mass ratio of 50 to (50-150) to (0-300) to (50-100) to (80-250) to (0.1-0.3).
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| CN109610427A (en) * | 2018-11-22 | 2019-04-12 | 中铁第勘察设计院集团有限公司 | Karst foundation visits the slip casting construction method for filling that combination, slurries are controllable, monitor in real time |
| CN110042840A (en) * | 2019-05-24 | 2019-07-23 | 中水北方勘测设计研究有限责任公司 | A kind of curtain-grouting method of steep dip bulk mosaic texture rock mass |
| CN111139853B (en) * | 2019-12-24 | 2021-03-30 | 同济大学 | High-flow-rate karst pipeline net hanging, stone hooking and grouting combined water plugging method |
| CN111424695B (en) * | 2020-04-17 | 2022-01-07 | 中国水利水电第八工程局有限公司 | Seepage-proofing and leakage-stopping method for deep-buried karst pipeline |
| CN112523170A (en) * | 2020-11-25 | 2021-03-19 | 上海勘测设计研究院有限公司 | Seepage-proofing treatment method for deep-buried karst seepage channel of reservoir |
| CN113174929B (en) * | 2021-05-08 | 2022-10-14 | 中铁上海设计院集团有限公司 | Karst building foundation composite reinforcement method under flowing water condition |
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| CN105887886B (en) * | 2016-06-16 | 2018-02-27 | 中国水利水电第十一工程局有限公司 | A kind of strong karsts developing area stratum Curtain Grouting Construction method |
| CN106320354B (en) * | 2016-08-23 | 2018-11-30 | 中国水利水电第八工程局有限公司 | The Seepage method on solution cavity development stratum under coating |
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