A system and method for reinforcing broken slopes by coupling liquid CO2 blasting and grouting

Abstract

The invention discloses a liquid CO 2 The method of reinforcing the broken slope by coupling blasting and grouting is to drill holes on the broken slope; use liquid CO 2 The high-pressure gas generated by the phase change squeezes the gravel in the broken layer of the slope around the borehole; the squeezed broken layer of the slope is grouted through the borehole, so that the gravel in the broken layer is bonded into a body, and finally a grouting area centered on the borehole is formed. In this process, the grouting areas of adjacent boreholes are connected into one by controlling the borehole spacing, so as to achieve the reinforcement of the entire slope broken layer. This method uses the high-pressure gas generated by the phase change of liquid CO2 to squeeze and densify the gravel around the borehole, and then performs high-pressure grouting to make the gravel in the squeezed area bonded into a body and finally form a grouting area centered on the borehole; in this process, the grouting areas of adjacent boreholes are connected by controlling the borehole spacing, and then a reinforcement surface is formed on the gravel surface to integrally reinforce the entire slope gravel body and achieve slope stability.

Description

Technical Field

[0001] The invention belongs to the technical field of slope protection, and particularly relates to a liquid CO 2 A system and method for reinforcing broken slopes by coupling blasting and grouting. Background Art

[0002] Slope reinforcement projects are widely involved in highway construction and operation, open-pit mining, stone dumping and other engineering safety. At present, the reinforcement of broken rock slope projects mainly includes anchor net method, anti-slide pile reinforcement, grouting reinforcement, etc. These methods are limited in reinforcement strength and range, and cannot well control the stability of slopes, especially the stability of broken slopes.

[0003] Patents CN2012104127996 and CN2012205512619 disclose an olive-shaped anti-slip key grouting anchor support blasting anchor rod. The patent constructs a new composite slope reinforcement and support system of olive-shaped reinforced anti-slip key-surrounding rock fissure grouting body-anchor support. Through a group anchor composed of multiple anchor rods, it can achieve comprehensive three-dimensional landslide prevention and control with the sliding surface as the anti-slip focus and rock and soil reinforcement, thereby improving the stability and safety of the slope.

[0004] However, the above patent forms an olive-shaped reinforced anti-slip key with the corresponding section of the anchor rod body as a reinforcement at the weak sliding structure surface, and the anti-slip key is extended through the grouting body in the surrounding rock cracks, thereby transforming the traditional anchor rod that mainly indirectly resists sliding by providing anchoring force into a system that relies on the olive-shaped reinforced anti-slip key, the grouting body in the surrounding rock cracks to directly resist sliding and the anchor rod to indirectly resist sliding and reinforce the rock and soil body. The broken slope layer is not reinforced, and the detonation gas generated by the explosion of the blasting charge will have a strong impact on the gravel in the broken slope layer, causing the broken slope layer to slide as a whole. Summary of the invention

[0005] The present application aims to solve at least one of the technical problems existing in the prior art. To this end, one of the purposes of the present invention is to provide a liquid CO2 blasting and grouting coupling reinforcement broken slope system and method which has a simple structure and can effectively prevent slope landslides.

[0006] A liquid CO 2 The method of reinforcing the broken slope by coupling blasting and grouting is to drill holes on the broken slope; use liquid CO 2 The high-pressure gas generated by the phase change squeezes the gravel in the broken layer of the slope around the borehole; the squeezed broken layer of the slope is grouted through the borehole, so that the gravel in the broken layer is bonded into a body, and finally a grouting area centered on the borehole is formed. In this process, the grouting areas of adjacent boreholes are connected into one by controlling the borehole spacing, thereby realizing the reinforcement of the entire slope broken layer.

[0007] Furthermore, a plurality of rigid cylinders corresponding to the drill holes are drilled on the broken slope, the rigid cylinders are coaxially arranged at the periphery of the corresponding drill holes, and the sides of the cylinders are evenly distributed with through holes for the grouting liquid to pass through.

[0008] Furthermore, the side wall of each rigid cylinder is tangent to the side wall of the adjacent rigid cylinder.

[0009] Furthermore, the rigid cylinders are distributed in a rectangular array on the broken slope.

[0010] Furthermore, the rigid cylinder extends into the compacted layer of the slope.

[0011] Furthermore, the borehole extends into the compacted layer of the slope.

[0012] A liquid CO 2 The blasting and grouting coupling reinforcement broken slope system includes a blasting component and a grouting component;

[0013] The blasting assembly includes a liquid CO buried in a borehole on the broken slope. 2 Phase change tube and liquid CO 2 The liquid CO 2 The phase change tube includes a liquid storage tube and an energy release head. The liquid storage tube is connected to the liquid CO via the liquid injection tube. 2 The delivery pump is connected, and a filling control valve is provided on the injection pipe;

[0014] The grouting assembly comprises a grouting pump and a grouting pipe, wherein the grouting pump is connected to the liquid CO through the grouting pipe. 2 The phase change pipe is connected, and a grouting control valve is provided on the grouting pipe;

[0015] The energy release head is located in the broken layer of the slope, a heating element is provided in the liquid storage pipe, a release pipeline connected to the liquid storage pipe is provided in the energy release head, an injection hole penetrating the release pipeline is provided on the outer wall, and a bursting piece is provided between the liquid storage pipe and the release pipeline.

[0016] Furthermore, it also includes a plurality of rigid cylinders installed on the broken slope and corresponding to the drill holes one by one, the rigid cylinders are coaxially arranged on the periphery of the corresponding drill holes, and the sides of the cylinders are evenly distributed with through holes for grouting liquid to pass through.

[0017] Furthermore, the side wall of each rigid cylinder is tangent to the side wall of the adjacent rigid cylinder.

[0018] Furthermore, the rigid cylinder extends into the compacted layer of the slope, the borehole extends into the compacted layer of the slope, and the liquid CO 2 An anchor rod inserted into the compression layer is provided at the bottom of the phase change tube.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1. The system uses high-pressure gas generated by the phase change of liquid CO2 to squeeze and densify the gravel around the borehole and form a drainage area around the borehole. Then, high-pressure grouting is performed to make the gravel in the squeezed area bond into a body and finally form a grouting area centered on the borehole. In this process, the grouting areas of adjacent boreholes are connected by controlling the borehole spacing, and then a reinforcement surface is formed on the gravel surface to reinforce the entire slope gravel body as a whole and achieve slope stability.

[0021] 2. By installing a rigid cylinder on the slope, and the rigid cylinder is coaxial with the corresponding borehole, when the high-pressure gas generated by the phase change of liquid CO2 squeezes the gravel, the energy is evenly dispersed along the borehole. When it is transmitted to the rigid cylinder, it will cancel each other out instead of continuing to transmit outward, thereby effectively preventing landslides when squeezing gravel.

[0022] 3. The gravel between the rigid cylinders in the broken layer cannot withstand the high-pressure gas, so the gap between the gravel is larger than that inside the cylinder. Under the same conditions, the seepage path always flows along the path where the seepage pressure decreases the fastest. Therefore, a grouting reinforcement area (central support column) will be formed between the rigid cylinders to connect the surrounding rigid cylinders into one, ensuring the reliability of the connection of each grouting area. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a structural schematic diagram of the present invention;

[0024] Figure 2 The liquid CO 2 Schematic diagram of the phase change tube structure;

[0025] Figure 3 This is a schematic diagram of the exhaust area formed after the explosion of liquid CO2 in the present invention;

[0026] Figure 4 It is a schematic diagram of forming a cohesive body by coupling grouting to reinforce a broken slope in the present invention;

[0027] Figure 5 It is a schematic diagram of the rigid cylinder structure in the present invention;

[0028] Figure 6 This is a schematic diagram of the spacing of broken stones in the broken layer before CO2 blasting;

[0029] Figure 7 Schematic diagram of the spacing between gravel in the broken layer after CO2 blasting. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] See also Figure 1 and Figure 2 , a liquid CO 2 The blasting and grouting coupling reinforcement broken slope system includes a blasting component and a grouting component; wherein,

[0032] The blasting assembly includes a liquid CO2 phase change tube 2 and a liquid CO2 delivery pump 3 buried in a borehole 1 on the broken slope. The liquid CO2 phase change tube 2 includes a liquid storage tube 201 and an energy release head 202. The liquid storage tube 201 is connected to the liquid CO2 delivery pump 3 through a liquid injection tube 4. The liquid injection tube 4 is provided with a liquid filling control valve 5. The grouting assembly includes a grouting pump 6 and a grouting tube 7. The grouting pump 6 is connected to the liquid CO2 phase change tube 2 through the grouting tube 7. The grouting tube 7 is provided with a grouting control valve 8.

[0033] The grouting pump 6 is connected to the slurry storage tank 9, the liquid CO2 delivery pump 3 is connected to the CO2 storage tank 10, the energy release head 202 is located in the broken layer 11 of the slope, a heating element is provided in the liquid storage pipe 201 (not shown in the figure), a release pipeline connected to the liquid storage pipe 201 is provided in the energy release head 202 (not shown in the figure), an injection hole 2021 penetrating the release pipeline is provided on the outer wall, and a bursting disc is provided between the liquid storage pipe 201 and the release pipeline (not shown in the figure).

[0034] Specifically in this embodiment, the energy-draining head 202 is coaxially sleeved outside the liquid storage tube 201. Of course, the liquid CO2 phase change tube 2 (fracture tube) can also adopt a tube body structure of other structures in the prior art.

[0035] Preferably, the grouting pipe 7 includes a grouting main pipe and a plurality of grouting branches branched out by a diverter valve 12, the liquid injection pipe 4 includes a liquid injection main pipe and a plurality of liquid injection branches branched out by a diverter valve 12, and a grouting control valve 8 is provided on both the grouting main pipe and the grouting branch pipe; a liquid filling control valve 5 is provided on both the liquid injection main pipe and the liquid injection branch pipe, and the liquid filling control valve 5 and the grouting control valve 8 are used to ensure that the sealing pressure of the liquid CO2 phase change tube 2 is greater than the transient high pressure generated by the CO2 explosion, and a flow meter 19 can also be provided on the liquid injection branch pipe and the grouting branch pipe.

[0036] See also Figure 3-Figure 5 , using the above liquid CO 2 The process of reinforcing the broken slope by coupling blasting and grouting is as follows:

[0037] Step 1: Drill holes 1 on the broken slope. The spacing of the holes 1 is twice the radius of the crushed stone compaction zone during liquid CO2 blasting. Place the liquid CO2 phase change tube 2 into the hole.

[0038] Step 2: close the grouting control valve 8 of the grouting main pipeline and its grouting branch pipeline, start the liquid filling pump and the liquid filling control valve 5, and inject the liquid CO2 in the CO2 storage tank 10 into the liquid CO2 phase change tube 2;

[0039] Step 3: turn off the liquid CO2 pump and the filling control valve 5, start the power supply so that the heating element heats the liquid CO2 in the liquid CO2 phase change tube 2 to make it change phase and expand. When the gas pressure is greater than the strength of the bursting disc, the bursting disc at the front end of the liquid storage tube 201 ruptures, and the high-pressure gas instantly enters the release pipeline and enters the borehole 1 from the injection hole 2021 on the energy release head 202. While creating the emptying area, the gravel around the borehole 1 is squeezed and compacted.

[0040] Step 4: Open the grouting control valve 8 of the grouting main pipeline and its grouting branch pipe, and the grouting pump 6 will let the reinforcement slurry enter the liquid CO2 phase change tube 2 through the pipeline, and flow out from the injection hole 2021 to grout and consolidate the crushed stone, and the crushed stone in the extrusion area will form a cohesive body 13. Finally, a grouting area 14 centered on the borehole 1 is formed, and the grouting areas 14 of adjacent boreholes 1 are connected by controlling the spacing between boreholes 1, thereby forming a reinforcement surface on the surface of the crushed stone, so as to integrally reinforce the entire slope crushed stone body and achieve the stability of the slope.

[0041] The system utilizes high-pressure gas generated by phase change of liquid CO2 to squeeze and densify the gravel around borehole 1 and form a drainage area around borehole 1. High-pressure grouting is then performed to make the gravel in the squeezed area bond together to eventually form a grouting area 14 centered on borehole 1. In this process, the grouting areas 14 of adjacent boreholes 1 are connected by controlling the spacing between boreholes 1, thereby forming a reinforced surface on the surface of the gravel to integrally reinforce the entire slope gravel body and achieve slope stability.

[0042] The principle of the present invention is to increase the bonding strength between particles by squeezing the surrounding crushed stones through CO2 blasting and connecting them through grouting. Figure 6 and Figure 7 As shown, F cap ,F total They respectively represent the static tensile strength and dynamic tensile strength between particles in the granules connected by the slurry.

[0043]

[0044]

[0045] Where V represents the volume of the grout between particles, d represents the surface distance between particles, and R 0is the particle radius, μ is the cohesion of the grout between particles, β is the slurry wetting angle, v is the relative movement speed between particles, and σ is the interfacial tension between the slurry and the particle surface.

[0046] It can be seen from this that when the slurry volume between particles is the same, the shorter the distance between particles, the stronger the static tensile strength and dynamic tensile strength between particles.

[0047] See also Figure 3-Figure 5 In some embodiments, the system further includes a plurality of rigid cylinders 15 which are installed on the broken slope and correspond to the boreholes 1 one by one. The rigid cylinders 15 are coaxially arranged at the periphery of the corresponding boreholes 1, and the sides of the cylinders are evenly distributed with through holes 1501 for the grouting liquid to pass through.

[0048] In this embodiment, a rigid cylinder 15 is installed on the slope, and the rigid cylinder 15 is coaxial with the corresponding borehole 1. When the high-pressure gas generated by the phase change of liquid CO2 squeezes the gravel, the energy is evenly dispersed along the borehole 1. When it is transmitted to the rigid cylinder 15, it will cancel each other out instead of continuing to be transmitted outward, thereby effectively preventing landslides from occurring when squeezing the gravel.

[0049] See also Figure 3 and Figure 5 In addition, the crushed stones between the rigid cylinders 15 in the broken layer 11 cannot withstand the high-pressure gas, so the gaps between the crushed stones are larger than those in the cylinders. Under the same conditions, the seepage path always flows along the path where the seepage pressure decreases the fastest. Therefore, a grouting reinforcement area 16 (central support column) will be formed between the rigid cylinders 15 to connect the surrounding rigid cylinders 15 into one, thereby ensuring the reliability of the connection of each grouting area 14.

[0050] Since the purpose of blasting in this embodiment is not to break the gravel but to squeeze and pile up the gravel under the action of high-pressure gas and produce a discharge area, the filling amount of liquid CO2 should be controlled in actual operation.

[0051] It can be understood that, in practical applications, the rigid cylinders 15 are distributed in a rectangular array on the crushing slope, and the side walls of each rigid cylinder 15 are tangent to the side walls of the adjacent rigid cylinders 15 .

[0052] It should be explained that, in other embodiments, the rigid cylinder 15 extends into the compaction layer 17 of the slope, the borehole 1 extends into the compaction layer 17 of the slope, and an anchor rod 18 inserted into the compaction layer 17 is provided at the bottom of the liquid CO2 phase change tube 2.

[0053] In this embodiment, the rigid cylinder 15 and the liquid CO2 phase change tube 2 are both extended into the compacted layer 17 of the slope, which is equivalent to anti-sliding piles, and the reinforced gravel layer is reinforced with anti-sliding piles.

[0054] The above embodiments are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. The obvious changes or modifications derived therefrom are still within the scope of protection of the present invention.

Claims

1. A method for reinforcing broken slopes by coupling liquid CO2 blasting and grouting, characterized in that: Drill holes on the broken slope; use the high-pressure gas generated by the phase change of liquid CO2 to squeeze the broken stones in the broken layer of the slope around the drill hole; inject grout into the squeezed broken layer of the slope through the drill hole, so that the broken stones in the broken layer are bonded together, and finally form a grouting area centered on the drill hole. In this process, the grouting areas of adjacent drill holes are connected into one by controlling the drill hole spacing, so as to achieve the reinforcement of the entire broken layer of the slope; A plurality of rigid cylinders corresponding to the drill holes are also provided on the broken slope. The rigid cylinders are coaxially arranged at the periphery of the corresponding drill holes, and the sides of the cylinders are evenly provided with through holes for the grouting liquid to pass through.

2. The method according to claim 1, characterized in that: The side wall of each rigid cylinder is tangent to the side wall of an adjacent rigid cylinder.

3. The method according to claim 1, characterized in that: The rigid cylinders are distributed in a rectangular array on the broken slope.

4. The method according to claim 1, characterized in that: The rigid cylinder extends into the compacted layer of the slope.

5. The method according to any one of claims 1 to 4, characterized in that: The borehole extends into the compacted layer of the slope.

6. A liquid CO2 blasting and grouting coupling system for reinforcing broken slopes, characterized in that: Including blasting components and grouting components; The blasting assembly includes a liquid CO2 phase change tube and a liquid CO2 delivery pump buried in a borehole on the broken slope, the liquid CO2 phase change tube includes a liquid storage tube and an energy discharge head, the liquid storage tube is connected to the liquid CO2 delivery pump through a liquid injection tube, and a liquid filling control valve is provided on the liquid injection tube; The grouting assembly comprises a grouting pump and a grouting pipe, the grouting pump is connected to the liquid CO2 phase change pipe through the grouting pipe, and the grouting pipe is provided with a grouting control valve; The energy-draining head is located in the broken layer of the slope, a heating element is arranged in the liquid storage pipe, a release pipeline connected to the liquid storage pipe is arranged in the energy-draining head, an injection hole penetrating the release pipeline is arranged on the outer wall, and a bursting disc is arranged between the liquid storage pipe and the release pipeline; and it also includes a plurality of rigid cylinders corresponding to the drill holes on the broken slope, the rigid cylinders are coaxially arranged on the periphery of the corresponding drill holes, and the sides of the cylinders are uniformly provided with perforations for the grouting liquid to pass through; The rigid cylinder extends into the compacted layer of the slope, the borehole extends into the compacted layer of the slope, and an anchor rod inserted into the compacted layer is provided at the bottom of the liquid CO2 phase change tube.

7. The system according to claim 6, characterized in that: The side wall of each rigid cylinder is tangent to the side wall of an adjacent rigid cylinder.

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