CN111963202A - Wet concrete spraying process for non-coal underground mine - Google Patents
Wet concrete spraying process for non-coal underground mine Download PDFInfo
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- CN111963202A CN111963202A CN202010635134.6A CN202010635134A CN111963202A CN 111963202 A CN111963202 A CN 111963202A CN 202010635134 A CN202010635134 A CN 202010635134A CN 111963202 A CN111963202 A CN 111963202A
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- concrete
- shotcrete
- water
- wet
- spraying
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Classifications
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- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
- E21D11/00—Lining tunnels, galleries or other underground cavities, e.g. large underground chambers; Linings therefor; Making such linings in situ, e.g. by assembling
- E21D11/04—Lining with building materials
- E21D11/10—Lining with building materials with concrete cast in situ; Shuttering also lost shutterings, e.g. made of blocks, of metal plates or other equipment adapted therefor
- E21D11/105—Transport or application of concrete specially adapted for the lining of tunnels or galleries ; Backfilling the space between main building element and the surrounding rock, e.g. with concrete
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B28—WORKING CEMENT, CLAY, OR STONE
- B28C—PREPARING CLAY; PRODUCING MIXTURES CONTAINING CLAY OR CEMENTITIOUS MATERIAL, e.g. PLASTER
- B28C5/00—Apparatus or methods for producing mixtures of cement with other substances, e.g. slurries, mortars, porous or fibrous compositions
- B28C5/08—Apparatus or methods for producing mixtures of cement with other substances, e.g. slurries, mortars, porous or fibrous compositions using driven mechanical means affecting the mixing
- B28C5/0875—Mixing in separate stages involving different containers for each stage
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B28/00—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
Abstract
The invention discloses a wet concrete spraying process for a non-coal underground mine, which comprises the following steps: (1) preparing semi-finished concrete; sending sand, stone, cement, a concrete hydrating agent except for an accelerating agent and water into a ground forced mixer for primary stirring to prepare semi-finished concrete, and adding water according to a water-cement ratio of 0.28-0.30; (2) preparing finished concrete; feeding the semi-finished concrete to a double-screw stirring conveyor, adding water and a water reducing agent, and mixing for the second time to obtain finished concrete, wherein the water is added according to the water-cement ratio of 0.55-0.6; (3) concrete spraying operation; and (3) conveying the prepared finished concrete to a hopper of a wet spraying machine through a double-helix stirring conveyor, uniformly mixing the accelerating agent and the stirred finished concrete, and spraying the mixture onto the surface of the excavated roadway or chamber rock through the wet spraying machine. The invention adopts a concrete secondary mixing process, and can meet the requirements of mixture workability required by injection equipment and processes and continuously supply materials to the injection equipment.
Description
Technical Field
The invention belongs to the technical field of wet-spraying support, and particularly relates to a wet concrete spraying process for a non-coal underground mine.
Background
After non-coal underground mine underworkings and chamber excavation, the original equilibrium state of three-dimensional stress of surrounding rock is broken in tunnel and chamber top group, in order to keep the stability of tunnel and chamber, avoid the surrounding rock to appear caving or too big deformation, generally all need strut after the tunnel tunnelling, the mode of strutting of underworkings and chamber has: anchor bolt support, anchor bolt and anchor net guniting support, plain guniting support, cast-in-place reinforced concrete support and the like. At present, most underground mines in China adopt anchor rod-anchor net support and anchor rod-anchor net guniting support technologies, wherein the anchor rod-anchor net guniting support can fully play the role of an anchor rod and the role of concrete. At present, the underground mine in China generally adopts a dry-spraying concrete support technical scheme.
Most of underground mine development projects are arranged in rock masses, the partial rock masses are easy to weather and expand when meeting water after the projects are disclosed, the shaft and tunnel projects in the rock masses need to be supported in time on full sections, the requirement on supporting strength is high, the supporting quantity is large, the requirement on the mine development construction period is tight, dry-type sprayed concrete is adopted, namely sand, stone, cement and an accelerating agent are conveyed to an operation surface for storage, workers mix the sand, the stone, the cement and the accelerating agent according to rough proportions according to experience during construction, and compressed air is used as power to be sprayed onto the rock surface through a spraying machine. Because the concrete mixing proportion of the process has no quality assurance measures, particularly the cement proportion is randomly changed (dry material conveying, cement aggregate segregation), the water-cement ratio is random (operators manually control randomly by switching on and off), the powdery accelerator is unevenly added (manual throwing, local excessive peak pits are formed, local insufficient slump and cracking are caused), the spraying layer has low structural strength and large fluctuation, the concrete has high resilience and the like, the supporting strength of a roadway cannot meet the requirements, and potential safety hazards exist; particularly, in the dry spraying construction, because cement particles in the mixture exist in a powder form, a large amount of SiO2 dust is generated in the transportation and spraying processes, and silicosis harm is caused to workers. The supporting strength of the concrete constructed by the mold can meet the requirement, but the labor intensity is high, the efficiency is low, and the supporting speed can not meet the requirement of the construction progress.
Disclosure of Invention
Aiming at the problems in the prior art, the invention provides a wet concrete spraying process for a non-coal underground mine.
The invention realizes and solves the technical problems through the following technical means: a wet concrete spraying process for a non-coal underground mine comprises the following steps:
(1) preparation of semi-finished concrete
Sending sand, stone, cement, a concrete hydrating agent except for an accelerating agent and water into a ground forced mixer for primary stirring to prepare semi-finished concrete, and adding water according to a water-cement ratio of 0.28-0.30;
(2) preparation of finished concrete
Feeding the semi-finished concrete to a double-screw stirring conveyor, adding water and a water reducing agent, and mixing for the second time to obtain finished concrete, wherein the water is added according to the water-cement ratio of 0.55-0.6;
(3) concrete spraying operation
And (3) conveying the prepared finished concrete to a hopper of a wet spraying machine through a double-helix stirring conveyor, uniformly mixing the accelerating agent and the stirred finished concrete, and spraying the mixture onto the surface of the excavated roadway or chamber rock through the wet spraying machine.
Further, the feeding sequence in the step (1) of preparing the semi-finished concrete is as follows: firstly, adding pebbles and sand, and then adding cement, a concrete hydrating agent except an accelerating agent and water; the stirring time of the stirrer is not less than 90 seconds.
Further, in the concrete spraying operation of the step (3), the spraying sequence is from wall to arch, from bottom to top; the side wall should start from the wall base and the arch from the arch foot.
Further, the concrete in the step (3)During spraying, the spraying pressure is 4-6MPa, and the spraying flow is controlled at 5-6m3And h, the included angle between the axis of the nozzle and the sprayed rock surface is more than or equal to 75 degrees, and the distance between the nozzle and the sprayed rock surface is kept within the range of 0.6-1.5 m.
Further, after the concrete is sprayed in the step (3), sweeping and leveling are carried out, the sweeping thickness is 30-50 mm, and the distance between the nozzle and the rock surface to be sprayed is kept within the range of 1.5-2 m during sweeping.
Further, the concrete once-spraying thickness is as follows: the side wall is 80-150 mm, and the arch part is 60-100 mm.
And (3) further, the concrete spraying operation in the step (3) adopts layered spraying, and the spraying of the later layer is carried out after the final setting of the concrete of the former layer.
Furthermore, when the latter layer is sprayed after the former layer of concrete is finally set for 1h, the surface of the sprayed layer is cleaned by high-pressure wind or water.
Furthermore, before the concrete spraying operation in the step (3) is started, the operation surface obstacles need to be removed, pumice and rock slag and piled materials at the wall base need to be removed, and the sprayed surface needs to be cleaned by high-pressure air or water.
The invention has the beneficial effects that:
1. the invention provides a secondary concrete mixing process, which solves the problems of the metered addition of other mixing water and water reducing agents in the designed mixing proportion, the preparation of mixtures meeting the requirements of injection equipment and processes on workability and the continuous feeding of the mixtures to the injection equipment. By adopting the underground wet concrete guniting process and system for the non-coal underground mine, the storage time (72 hours) of the concrete primary mixture can meet the requirements of the wet shotcrete construction of most mine roadways under the conditions of reasonable use of a hydrating agent, a water-cement ratio and a cement using amount, and the strength meets the design requirement.
2. The thickness of the primary sprayed layer of the sprayed concrete can reach 10-15cm under the condition that the anchor nets of mine roadways or chambers are denser.
3. Through the volume method concrete rebound test, the comprehensive wet-spraying rebound rate is 15-20%, and the material is saved.
4. The horizontal distance of wet spraying construction can completely reach 40 meters. And from field situation analysis of 40 meter jets, horizontal jet distances up to 60 meters are possible.
5. The wet spraying process greatly reduces the dust of spraying operation, improves the working environment of spraying concrete, ensures the physical and mental health of workers and simultaneously improves the working efficiency.
6. The strength of the sprayed concrete is improved, supporting parameters are optimized, the later maintenance cost of the roadway is reduced, the overhauling rate of the roadway is reduced, and the safety level is improved.
Drawings
FIG. 1 is a flow chart of a wet shotcrete process according to an embodiment of the present invention;
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 drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. 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.
Examples
As shown in fig. 1, a wet shotcrete process for a non-coal underground mine,
the raw materials and requirements for the process are, in particular,
cement: preferably 42.5R-grade ordinary portland cement is selected;
coarse aggregate stones: the sprayed concrete is made of stones with the particle size of 5-12 mm, and the mud content is less than or equal to 2%.
Fine aggregate sand: spraying concrete: medium coarse sand with fineness modulus Mx of 2.5-3.2 is selected, the mud content is less than or equal to 3%, and the water content is less than or equal to 7%.
Water: domestic water is selected, and the treated industrial water is required to be checked to meet the regulation of the concrete mixing water standard (JGJ 63-89), wherein the industrial water can be used without acid, alkali and oil.
Concrete admixture: the admixture produced by qualified manufacturers is selected.
Liquid accelerator: the liquid setting accelerator produced by a qualified manufacturer is selected, the initial setting time is less than or equal to 5min, and the final setting time is less than or equal to 10 min.
The method comprises the following steps: (1) and (3) preparing the semi-finished concrete, specifically, conveying the sand and stone stored in the ground surface proportioning machine, the cement and concrete hydration agent (except the accelerating agent) stored on the ground surface and water (added according to the water-cement ratio of 0.28-0.30) into a ground forced mixer according to the designed proportion for primary mixing to prepare the semi-finished concrete. Specifically, the allowable deviation of the weighing of cement and the accelerator is +/-2%, and the allowable deviation of the weighing of sand and gravel is +/-3%. The feeding sequence is that stones and sand are firstly added, and then cement is added; mechanical stirring is adopted, and the stirring time is not less than 90 seconds. Through reasonable use of the hydrating agent, the requirement of storing for 3 days can be met by mixing the concrete for one time. The hydrating agent should be added in the form of a solution, and when the hydrating agent is used, the hydrating agent is added to the mixing water, and the amount of water in the solution should be subtracted from the amount of mixing water.
And (3) transporting the semi-finished concrete, specifically, conveying the semi-finished concrete material made on the ground surface to an underground construction operation point for piling by using an engineering transport vehicle through an auxiliary well cage or a conveying pipeline.
(2) And (3) preparing finished concrete, specifically, manually feeding the semi-finished concrete material piled at the construction operation point to a double-screw stirring conveyor, adding water (enough according to the water-cement ratio of 0.55-0.6) and a water reducing agent, and mixing to obtain the finished concrete.
(3) Concrete spraying operation: specifically, removing obstacles on a working face, removing rock slag and piled objects of pumice and wall feet, cleaning a sprayed face by using high-pressure air or water, conveying prepared finished concrete to a hopper of a wet spraying machine through a double-screw stirring conveyor, uniformly mixing an accelerator and the stirred finished concrete by using compressed air, spraying the mixture onto the rock face of an excavated tunnel or chamber at a high speed, and quickly solidifying, wherein the spraying sequence is wall first and arch later and from bottom to top; the side wall is started from the wall base, and the arch part is started from the arch foot; primary spraying thickness of plain sprayed concrete: the side walls are 80-150 mm, the arch parts are 60-100 mm, and the injection of the reinforcing mesh and the arch truss can be properly increased; when spraying in layers, the spraying of the later layer should be carried out after the final setting of the previous layer of concrete, and if spraying is carried out after 1h of final setting, high pressure should be firstly appliedCleaning the surface of the sprayed layer by wind or water; when in spraying, the included angle between the axis of the nozzle and the sprayed rock surface is more than or equal to 75 degrees, and the distance between the nozzle and the sprayed rock surface is kept within the range of 0.6-1.5 m. The distance between the nozzle and the rock surface to be sprayed is kept within the range of 1.5-2 m during the face sweeping; in order to ensure the flatness of the spraying surface, the surface is swept and leveled, and the swept thickness is 30-50 mm; when in spraying, the working air is as small as possible under the condition of ensuring no pipe blockage so as to reduce rebound, and the air quantity can be properly increased when in surface sweeping so as to ensure the flatness of the spraying surface. When spraying, the spraying pressure is 4-6Mpa, and the spraying flow is controlled at 5-6m3/h。
Under the conditions of water-cement ratio of 0.5, 0.55 and 0.6, the cement dosage is 410kg/m3In the meantime, the secondary stirring sprayed concrete in 3 days meets the requirement of the C20 primary support strength of the mine roadway, and most of the secondary stirring sprayed concrete reaches the C30 grade.
The invention provides a secondary concrete mixing process, which solves the problems of the metered addition of other mixing water and water reducing agents in the designed mixing proportion, the preparation of mixtures meeting the requirements of injection equipment and processes on workability and the continuous feeding of the mixtures to the injection equipment. By adopting the underground wet concrete guniting process and system for the non-coal underground mine, the storage time (72 hours) of the concrete primary mixture can meet the requirements of the wet shotcrete construction of most mine roadways under the conditions of reasonable use of a hydrating agent, a water-cement ratio and a cement using amount, and the strength meets the design requirement.
The thickness of the primary sprayed layer of the sprayed concrete can reach 10-15cm under the condition that the anchor nets of mine roadways or chambers are denser.
Through the volume method concrete rebound test, the comprehensive wet-spraying rebound rate is 15-20%, and the material is saved. The horizontal distance of wet spraying construction can completely reach 40 meters. And from field situation analysis of 40 meter jets, horizontal jet distances up to 60 meters are possible. The wet spraying process greatly reduces the dust of spraying operation, improves the working environment of spraying concrete, ensures the physical and mental health of workers and simultaneously improves the working efficiency. The strength of the sprayed concrete is improved, supporting parameters are optimized, the later maintenance cost of the roadway is reduced, the overhauling rate of the roadway is reduced, and the safety level is improved.
It is noted that, in this document, relational terms such as first and second, and the like, if any, are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.
The above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.
Claims (9)
1. A wet concrete spraying process for a non-coal underground mine is characterized by comprising the following steps:
(1) preparation of semi-finished concrete
Sending sand, stone, cement, a concrete hydrating agent except for an accelerating agent and water into a ground forced mixer for primary stirring to prepare semi-finished concrete, and adding water according to a water-cement ratio of 0.28-0.30;
(2) preparation of finished concrete
Feeding the semi-finished concrete to a double-screw stirring conveyor, adding water and a water reducing agent, and mixing for the second time to obtain finished concrete, wherein the water is added according to the water-cement ratio of 0.55-0.6;
(3) concrete spraying operation
And (3) conveying the prepared finished concrete to a hopper of a wet spraying machine through a double-helix stirring conveyor, uniformly mixing the accelerating agent and the stirred finished concrete, and spraying the mixture onto the surface of the excavated roadway or chamber rock through the wet spraying machine.
2. The wet shotcrete process for non-coal underground mine according to claim 1, wherein the feeding sequence in the step (1) of preparing the semi-finished concrete is as follows: firstly, adding pebbles and sand, and then adding cement, a concrete hydrating agent except an accelerating agent and water; the stirring time of the stirrer is not less than 90 seconds.
3. The wet shotcrete process for non-coal underground mine according to claim 1, wherein in the concrete shotcrete operation of step (3), the shotcrete sequence is from wall to arch, from bottom to top; the side wall should start from the wall base and the arch from the arch foot.
4. The wet shotcrete process for non-coal underground mine according to claim 1, wherein the shotcrete pressure is 4-6Mpa, and the shotcrete flow rate is controlled to be 5-6m during shotcrete operation in the step (3)3And h, the included angle between the axis of the nozzle and the sprayed rock surface is more than or equal to 75 degrees, and the distance between the nozzle and the sprayed rock surface is kept within the range of 0.6-1.5 m.
5. The wet shotcrete process for the non-coal underground mine according to claim 1, wherein after the concrete shotcrete operation in the step (3), the sweeping is leveled, the sweeping thickness is 30-50 mm, and the distance between the nozzle and the rock surface to be shotcrete is kept within a range of 1.5-2 m during sweeping.
6. The wet shotcrete process for non-coal underground mine according to any one of claims 1 to 5, wherein the concrete primary spraying thickness is as follows: the side wall is 80-150 mm, and the arch part is 60-100 mm.
7. The wet shotcrete process for non-coal underground mine according to any one of claims 1 to 5, wherein the concrete shotcrete operation in step (3) is performed by layer shotcrete, and the shotcrete operation of the later layer is performed after the concrete of the former layer is finally set.
8. The wet shotcrete process for non-coal underground mine according to claim 7, wherein when the later layer of shotcrete is performed after the previous layer of concrete is finally set for 1 hour, the surface of the shotcrete layer is cleaned by high pressure wind or water.
9. The wet shotcrete process for non-coal underground mine according to claim 1, wherein before the concrete shotcrete operation in step (3) is started, the operation surface obstacles are removed, the pumice and the rock slag and the piled materials of the wall foot are removed, and the sprayed surface is cleaned by high pressure wind or water.
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| CN202010635134.6A CN111963202A (en) | 2020-07-03 | 2020-07-03 | Wet concrete spraying process for non-coal underground mine |
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101749031A (en) * | 2009-12-24 | 2010-06-23 | 北京交通大学 | Compound grouting reinforcement method for subsea tunnel going through water-rich sand stratum |
| CN105401947A (en) * | 2015-10-26 | 2016-03-16 | 中铁二十局集团有限公司 | Large-deformation control construction method for high ground stress weak surrounding rock tunnel |
| CN107762535A (en) * | 2017-10-30 | 2018-03-06 | 重庆城建控股(集团)有限责任公司 | Cut-and-cover tunnel secretly does construction technology under complicated geological environment |
| CN109162732A (en) * | 2018-08-21 | 2019-01-08 | 华东建工集团有限公司 | A kind of shotcrete construction method |
| CN109209392A (en) * | 2018-09-10 | 2019-01-15 | 中铁二院成都勘察设计研究院有限责任公司 | Loopful excavation method suitable for IV-V grade of country rock of large cross-section tunnel |
| CN109485320A (en) * | 2018-11-28 | 2019-03-19 | 铜陵有色金属集团股份有限公司 | The operating method of wet sprayed concrete technique for light section mine working |
| CN109707403A (en) * | 2018-12-10 | 2019-05-03 | 中交一公局桥隧工程有限公司 | A kind of construction of shotcrete technique |
-
2020
- 2020-07-03 CN CN202010635134.6A patent/CN111963202A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101749031A (en) * | 2009-12-24 | 2010-06-23 | 北京交通大学 | Compound grouting reinforcement method for subsea tunnel going through water-rich sand stratum |
| CN105401947A (en) * | 2015-10-26 | 2016-03-16 | 中铁二十局集团有限公司 | Large-deformation control construction method for high ground stress weak surrounding rock tunnel |
| CN107762535A (en) * | 2017-10-30 | 2018-03-06 | 重庆城建控股(集团)有限责任公司 | Cut-and-cover tunnel secretly does construction technology under complicated geological environment |
| CN109162732A (en) * | 2018-08-21 | 2019-01-08 | 华东建工集团有限公司 | A kind of shotcrete construction method |
| CN109209392A (en) * | 2018-09-10 | 2019-01-15 | 中铁二院成都勘察设计研究院有限责任公司 | Loopful excavation method suitable for IV-V grade of country rock of large cross-section tunnel |
| CN109485320A (en) * | 2018-11-28 | 2019-03-19 | 铜陵有色金属集团股份有限公司 | The operating method of wet sprayed concrete technique for light section mine working |
| CN109707403A (en) * | 2018-12-10 | 2019-05-03 | 中交一公局桥隧工程有限公司 | A kind of construction of shotcrete technique |
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