A grouting method and a grouting system

Abstract

The present invention discloses a grouting method and a grouting system. The grouting method comprises the following steps: a plurality of drill holes are formed on a grouting curtain line, the drill holes include positive-pressure drill holes and negative-pressure drill holes, the positive-pressure drill holes and the negative-pressure drill holes are arranged alternately in sequence, the positive-pressure drill holes are divided into a plurality of grouting sections, a sealing plug is arranged at the upper end of the grouting section near the lowermost end of the positive-pressure drill hole, and similarly, plugging sections are formed by plugging with sealing plugs in two adjacent negative-pressure drill holes; grouting is carried out on the grouting section at the lowermost end of the positive-pressure drill hole, and simultaneously, water pumping and air extraction are carried out on the plugging sections of the two adjacent negative-pressure drill holes; when the grouting pressure of the grouting section of the positive-pressure drill hole reaches the designed grouting pressure, grouting of the grouting section of the positive-pressure drill hole is stopped, and simultaneously, water pumping and air extraction of the plugging sections of the two adjacent negative-pressure drill holes are stopped, and grouting of one grouting section is completed; the above grouting steps are repeated to carry out grouting on the positive-pressure drill holes from bottom to top in sequence until the grouting of the whole positive-pressure drill hole is completed.

Description

Technical Field

[0001] The present invention relates to the field of curtain grouting for fractured rock masses, and particularly to a method and a system for curtain grouting of fractured rock masses. Background Art

[0002] Curtain grouting for fractured rock masses is a widely used technical measure in the process of underground engineering development, which can play a dual role of strengthening fractured rock masses and blocking water flow channels. For example, curtain grouting for water blocking in mines, curtain grouting for reinforcement of roadways, and curtain grouting for intercepting flow in dam foundations. However, a large number of grouting engineering practices have shown that the diffusion of grout in fractured rock masses is extremely uneven. Most of the grout will diffuse farther along several wide fractures, even exceeding several kilometers, while the grout cannot effectively diffuse in relatively small fractures. This uneven diffusion phenomenon of grout in the rock fracture network is called the preferential flow effect of grout diffusion. Due to the existence of the preferential flow effect of grout diffusion in the rock fracture network, there are a large number of small fractures in the rock mass that cannot be filled and blocked by grout, becoming potential seepage channels for groundwater and weak positions of the grouting curtain. At the same time, this preferential flow effect of grout diffusion will also cause ground loss of grout, resulting in a large amount of grout waste and pollution to the ecological environment on the surface. For a long time, there has been no effective engineering measure for the phenomenon of water blocking failure of the grouting curtain caused by uneven diffusion of grout in fractured rock masses and a large amount of ground loss of grout. In order to solve the above engineering problems and effectively control the diffusion of grout in the complex rock fracture network to achieve an ideal grouting effect, there is an urgent need for a method for controlling the deviation of curtain grouting by inducing grout diffusion through sectional negative pressure in boreholes. Summary of the Invention

[0003] In view of the problems and requirements mentioned above, the present solution provides a grouting method and a grouting system, which can achieve the above technical objectives and bring many other technical effects due to the following technical features.

[0004] An object of the present invention is to provide a grouting method, which includes the following steps:

[0005] S10: Open a plurality of boreholes on the grouting curtain line. The boreholes include positive-pressure boreholes and negative-pressure boreholes, and the positive-pressure boreholes and the negative-pressure boreholes are arranged alternately in sequence. Among them, the positive-pressure boreholes are configured to inject grout into the boreholes, and the negative-pressure boreholes are configured to pump water and air out of the boreholes;

[0006] S20: Divide the positive-pressure boreholes into a plurality of grouting sections, and set a sealing plug at the upper end of the grouting section closest to the lower end of the positive-pressure borehole. Similarly, form a sealed section in the two adjacent negative-pressure boreholes with sealing plugs;

[0007] S30: Inject grout into the grouting section at the lowest end of the positive-pressure borehole, and simultaneously pump water and air from the plugging sections of the two adjacent negative-pressure boreholes. Continuously create negative pressure within the plugging sections, and the negative pressure will be conducted through the fracture network to the grouting section of the positive-pressure borehole, inducing the grout to spread to the two adjacent negative-pressure boreholes;

[0008] S40: When the grouting pressure in the grouting section of the positive-pressure borehole reaches the designed grouting pressure, stop injecting grout into the grouting section of the positive-pressure borehole, and simultaneously stop pumping water and air from the plugging sections of the two adjacent negative-pressure boreholes to complete the grouting of one grouting section;

[0009] S50: Repeat steps S20 to S40, and grout the positive-pressure borehole from bottom to top in sequence until the grouting of the entire positive-pressure borehole is completed.

[0010] In this technical solution, this grouting method can not only effectively control the deviation flow effect of the grout diffusion in the rock mass fractures, make the grout diffusion more uniform, but also increase the effective diffusion radius of the grout, change the original "grouting hole by hole" to "alternate hole grouting", greatly improving the grouting efficiency and effect while saving a large amount of engineering cost and construction period.

[0011] In addition, according to the grouting method of the present invention, it may also have the following technical features:

[0012] In an example of the present invention, after step S50, it further includes:

[0013] Inspecting the grouting effect of the positive-pressure borehole, which includes: using the negative-pressure borehole as the inspection borehole of the positive-pressure borehole, and when a weak position in the grouting of the positive-pressure borehole is found, supplement grouting into the positive-pressure borehole through the negative-pressure borehole.

[0014] In an example of the present invention, after step S50, it further includes:

[0015] After inspecting that the grouting of the positive-pressure borehole meets the design requirements, grout and plug the negative-pressure borehole to eliminate the hidden danger of the negative-pressure borehole as a seepage channel.

[0016] In an example of the present invention, the grouting liquid used for grouting and plugging the negative-pressure borehole is a double-fluid grout of cement and water glass.

[0017] In an example of the present invention, in step S20, the depth of each grouting section is 15 m ~20 m .

[0018] In an example of the present invention, in step S20, the packing plugs in the positive-pressure borehole and the packing plugs in the two adjacent negative-pressure boreholes are located at the same depth position.

[0019] In an example of the present invention, in step S30, the grouting pressure in the grouting section of the positive-pressure borehole is less than or equal to the negative pressure in the plugging section of the negative-pressure borehole.

[0020] Another object of the present invention is to provide a grouting system, comprising:

[0021] A plurality of boreholes opened on the grouting curtain line, including positive-pressure boreholes and negative-pressure boreholes, wherein the positive-pressure boreholes and the negative-pressure boreholes are arranged alternately in sequence;

[0022] Sealing plugs, installed in the positive-pressure boreholes and the negative-pressure boreholes adjacent to the positive-pressure boreholes, wherein the sealing plugs and the lower end portions of the corresponding positive-pressure boreholes form a grouting section, and the sealing plugs and the lower end portions of the corresponding negative-pressure boreholes form a plugging section;

[0023] A grouting pump, one end of which is connected to an external slurry source, and the other end of which is connected to the grouting section;

[0024] A water pump, having a water pumping port, and the water pumping port is connected to the plugging section; and

[0025] An air pump, having an air pumping port, and the air pumping port is connected to the plugging section.

[0026] In an example of the present invention, the sealing plugs in the positive-pressure boreholes and the sealing plugs in the two adjacent negative-pressure boreholes are located at the same depth position.

[0027] In an example of the present invention, the grouting pressure injected into the grouting section by the grouting pump is less than or equal to the negative pressure formed by the water pump and the air pump in the plugging section.

[0028] In the following, the optimal embodiments of implementing the present invention will be described in more detail with reference to the accompanying drawings, so as to facilitate an easy understanding of the features and advantages of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings of the embodiments of the present invention will be briefly introduced below. Among them, the drawings are only used to show some embodiments of the present invention, rather than limiting all embodiments of the present invention thereto.

[0030] Figure 1 It is a schematic diagram of the cross-flow effect of slurry diffusion in a rock mass fracture network according to an embodiment of the present invention;

[0031] Figure 2 It is a schematic diagram of the implementation process of the a grouting section according to an embodiment of the present invention;

[0032] Figure 3 It is a schematic diagram of the implementation process of the b grouting section according to an embodiment of the present invention;

[0033] Figure 4 Schematic diagram of the implementation process of the c grouting section according to an embodiment of the present invention;

[0034] Figure 5 Flow chart of the grouting method according to an embodiment of the present invention.

[0035] List of reference numerals:

[0036] Grouting system 100;

[0037] Borehole 10;

[0038] Positive pressure borehole 11;

[0039] Negative pressure borehole 12;

[0040] Grouting section 10A;

[0041] Sealing section 10B;

[0042] Sealing plug 20;

[0043] Grouting pump 30;

[0044] Water pump 40;

[0045] Air extraction pump 50;

[0046] Wide crack K;

[0047] Narrow crack X. Detailed implementation manners

[0048] In order to make the objectives, technical solutions, and advantages of the technical solutions of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the drawings of the specific embodiments of the present invention. The same reference numerals in the drawings represent the same components. It should be noted that the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the described embodiments of the present invention without creative efforts shall fall within the scope of protection of the present invention.

[0049] Unless otherwise defined, technical terms or scientific terms used herein shall have the ordinary meanings as understood by those of ordinary skill in the art to which this invention pertains. The terms "first", "second" and similar terms used in the specification and claims of this patent application for invention do not denote any order, quantity or importance, but are only used to distinguish different components. Similarly, terms such as "a" or "an" do not necessarily denote a quantity limitation. Terms such as "comprising" or "including" mean that the elements or items appearing before this term cover the elements or items listed after this term and their equivalents, without excluding other elements or items. Terms such as "connected" or "coupled" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. Terms such as "upper", "lower", "left" and "right" are only used to indicate relative positional relationships, and when the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0050] Figure 1 It is a schematic diagram of the preferential flow effect of slurry diffusion in the rock mass fracture network, that is, the form of the slurry consolidation body formed by the current traditional drilling 10 grouting method around the drilling 10. It can be seen that the slurry diffuses farther in the relatively wide fracture K around the drilling 10, and the diffusion distance of the slurry around the fine fracture X is relatively close. This preferential flow diffusion will not only cause a large amount of slurry to diffuse to positions ineffective for the curtain grouting effect, not only make the engineering effect unsatisfactory, but also waste a large amount of slurry; therefore, it is urgent to take measures in engineering to control the generation of the preferential flow effect of slurry diffusion in the fracture.

[0051] Figures 2 to 4 It is a schematic diagram of the implementation process of the a, b, and c grouting sections according to the embodiments of the present invention. Figure 5 It is a flow chart of the grouting method implemented according to the present invention.

[0052] A grouting method according to the first aspect of the present invention, as Figures 2 to 5 shown, includes the following steps:

[0053] S10: Open a plurality of drill holes 10 on the grouting curtain line. The drill holes 10 include positive-pressure drill holes 11 and negative-pressure drill holes 12. The positive-pressure drill holes 11 and the negative-pressure drill holes 12 are arranged alternately in sequence. Among them, the positive-pressure drill holes 11 are configured to grout into the drill holes 10, and the negative-pressure drill holes 12 are configured to pump water and air out of the drill holes 10; for example, number the drill holes 10 in sequence, and set the drill holes 10 with even numbers as positive-pressure drill holes 11, numbered Z2, Z4, Z6, Z8... Z2N respectively; set the drill holes 10 with odd numbers as negative-pressure drill holes 12, numbered Z1, Z3, Z5, Z7... Z2N + 1 respectively; the positive-pressure drill holes 11 are grouting drill holes, and the negative-pressure drill holes 12 are water and air pumping drill holes;

[0054] S20: Divide the positive-pressure borehole 11 into multiple grouting sections 10A. Set a sealing plug 20 at the upper end of the grouting section 10A closest to the bottom end of the positive-pressure borehole 11. Similarly, use the sealing plug 20 to block and form a blocked section 10B in two adjacent negative-pressure boreholes 12;

[0055] S30: Grout the grouting section 10A at the bottom end of the positive-pressure borehole 11. At the same time, pump water and air out of the blocked sections 10B of the two adjacent negative-pressure boreholes 12. Continuously form negative pressure in the blocked sections 10B. The negative pressure will be conducted to the grouting section 10A of the positive-pressure borehole 11 through the fracture network, inducing the grout to spread to the two adjacent negative-pressure boreholes 12;

[0056] S40: When the grouting pressure of the grouting section 10A of the positive-pressure borehole 11 reaches the designed grouting pressure, stop grouting the grouting section 10A of the positive-pressure borehole 11. At the same time, stop pumping water and air out of the blocked sections 10B of the two adjacent negative-pressure boreholes 12 to complete the grouting of one grouting section 10A;

[0057] S50: Repeat steps S20 to S40 to grout the positive-pressure borehole 11 from bottom to top in sequence until the grouting of the entire positive-pressure borehole 11 is completed.

[0058] The core principle of this grouting method is to set negative-pressure boreholes 12 (for pumping water and air) on both sides of the positive-pressure borehole 11 (for grouting). Through the suction effect of negative pressure and the driving effect of grouting pressure, the grout can not only spread in wide fractures K but also in relatively fine fractures, and the spread of the grout is more uniform, effectively avoiding the ineffective spread range of the grout and waste of the grout. Among them, the generation of negative pressure in the borehole 10 mainly relies on the continuous operation of the water pump 40 and the air pump 50 to induce the grout to spread evenly to both sides, ultimately achieving an ideal grouting effect and forming a stable grouting curtain. At the same time, the curtain grouting method proposed by the present invention also changes the traditional "grouting hole by hole" into "alternate hole grouting". The negative-pressure borehole 12 can also be used as a grouting effect inspection borehole 10 and a supplementary grouting borehole, significantly improving the grouting effect and efficiency. Moreover, this method has good application prospects in engineering fields such as mine curtain grouting for water blocking, roadway curtain grouting for reinforcement, and dam foundation curtain grouting for cut-off.

[0059] This grouting method can not only effectively control the deviation flow effect of the grout spread in the rock mass fractures, making the grout spread more evenly, but also increase the effective spread radius of the grout, changing the original "grouting hole by hole" into "alternate hole grouting". While greatly improving the grouting efficiency and effect, it saves a large amount of project cost and construction period.

[0060] In an example of the present invention, after step S50, it further includes:

[0061] The inspection of the grouting effect of the positive-pressure borehole 11 includes: using the negative-pressure borehole 12 as the inspection borehole for the positive-pressure borehole 11. When a weak position in the grouting of the positive-pressure borehole 11 is found, supplementary grouting is carried out into the positive-pressure borehole 11 through the negative-pressure borehole 12;

[0062] By using the negative-pressure borehole 12 as the inspection borehole, supplementary grouting can be continuously carried out on the weak positions of the grouting of the positive-pressure borehole 11, thereby ensuring the reliable quality of the grouting of the positive-pressure borehole 11.

[0063] In an example of the present invention, after step S50, it further includes:

[0064] After it is inspected that the grouting of the positive-pressure borehole 11 meets the design requirements, the negative-pressure borehole 12 is grouted and blocked to eliminate the hidden danger of the negative-pressure borehole 12 as a seepage channel;

[0065] That is to say, since the negative-pressure borehole 12 is arranged on both sides of the positive-pressure borehole 11 and may be connected to the positive-pressure borehole 11 through cracks, in order to avoid the occurrence of the negative-pressure borehole 12 as a seepage channel, after repeated verification, it is determined that the grouting of the positive-pressure borehole 11 meets the design requirements, and the negative-pressure borehole 12 needs to be grouted and blocked.

[0066] In an example of the present invention, the grouting liquid used for grouting and blocking the negative-pressure borehole 12 is a double-liquid slurry of cement and water glass.

[0067] In an example of the present invention, in step S20, the depth of each grouting section 10A is 15 m ~20 m ;

[0068] That is to say, the depth of each grouting section 10A is selected to be 15 m ~20 m is an optimal depth, which can realize effective grouting of the positive-pressure borehole 11.

[0069] In an example of the present invention, in the step S20, the plug 20 in the positive-pressure borehole 11 and the plugs 20 in the two adjacent negative-pressure boreholes 12 are located at the same depth position, so that the grouting section 10A can effectively induce the slurry to diffuse into the two adjacent negative-pressure boreholes 12, making the liquid diffusion more uniform.

[0070] In an example of the present invention, in step S30, the grouting pressure of the grouting section 10A in the positive-pressure borehole 11 is less than or equal to the negative pressure of the plugging section 10B in the negative-pressure borehole 12, that is, it can make the continuously formed negative pressure in the plugging section 10B conduct to the grouting section 10A of the positive-pressure borehole 11 through the fracture network, inducing the slurry to diffuse into the two adjacent negative-pressure boreholes 12.

[0071] In an example of the present invention, the sealing plug 20 is a rubber water stop plug; by injecting water into the rubber water stop plug, its expansion can be achieved, so as to be tightly sealed and connected with the inner wall of the drilling hole. Specific embodiments

[0072] For example, taking three drilling holes as an example for illustration, it includes 1 positive pressure drilling hole 11Z2 and 2 negative pressure drilling holes 12Z1 and Z3; among them, the positive pressure drilling hole 11 is provided with 3 grouting sections 10A, namely a grouting section 10A, b grouting section 10A, and c grouting section 10A; the sealing plugs 20 in the three drilling holes are: the sealing plug 20 in the positive pressure drilling hole 11 is the first rubber water stop plug, and the sealing plugs 20 in the two adjacent negative pressure drilling holes 12 are the second rubber water stop plugs. The specific steps are as follows:

[0073] S1. Place the first rubber water stop plug at the top of the lowest a grouting section 10A of the positive pressure drilling hole 11Z2. By injecting water into the rubber water stop plug, make the rubber water stop plug tightly fixed with the hole wall of the drilling hole; fix the two second rubber water stop plugs in the negative pressure drilling holes 12Z1 and 12Z3 respectively and at the same depth position as the first rubber water stop plug in the positive pressure drilling hole 11Z2.

[0074] S2. Grout the a grouting section 10A of the positive pressure drilling hole 11Z2 through the grouting pump 30, and at the same time pump water from the plugging sections 10B of the negative pressure drilling holes 12Z1 and 12Z3 through the water pump 40 and the air extraction pump 50. After the water in the drilling hole is pumped dry, continue to extract air; if there is no water in the plugging sections 10B of the negative pressure drilling holes 12Z1 and 12Z3, directly extract air through the air extraction pump 50; continuous air extraction will continuously form a negative pressure in the drilling hole, and the negative pressure will be conducted to the a grouting section 10A of the positive pressure drilling hole 11Z2 through the fracture network, inducing the slurry to diffuse towards the negative pressure drilling holes 12Z1 and 12Z3.

[0075] S3. When the a grouting section 10A at the lowest part of the positive pressure drilling hole 11Z2 reaches the designed grouting pressure, stop grouting the a grouting section 10A of the positive pressure drilling hole 11Z2, and at the same time stop pumping water and extracting air from the negative pressure drilling holes 12Z1 and 12Z3, then the grouting of the a grouting section 10A is completed.

[0076] S4. Move the first rubber water stop plug in the positive pressure drilling hole 11Z2 to the top of the b grouting section 10A, and at the same time move the second rubber water stop plugs in the negative pressure drilling holes 12Z1 and 12Z3 to the same depth as the first rubber water stop plug; and ensure tight fixation of the first rubber water stop plug, the second rubber water stop plug and the hole wall of the drilling hole by injecting water.

[0077] S5. Inject grout into the b grouting section 10A of the Z2 positive-pressure borehole 11 through the grout pump 30. At the same time, pump water out of the plugged sections 10B of the Z1 negative-pressure borehole 12 and the Z3 negative-pressure borehole 12 through the water pump 40 and the air extraction pump 50. After the water in the borehole is pumped dry, continue to extract air. If there is no water in the plugged sections 10B of the Z1 negative-pressure borehole 12 and the Z3 negative-pressure borehole 12, directly extract air through the air extraction pump 50. Continuous air extraction will continuously create negative pressure in the borehole, and the negative pressure will be conducted to the b grouting section 10A of the Z2 positive-pressure borehole 11 through the fracture network, inducing the grout to spread towards the Z1 negative-pressure borehole 12 and the Z3 negative-pressure borehole 12.

[0078] S6. When the b grouting section 10A in the middle of the Z2 positive-pressure borehole 11 reaches the designed grouting pressure, stop the grouting of the b grouting section 10A of the Z2 positive-pressure borehole 11. At the same time, stop the water pumping and air extraction of the Z1 negative-pressure borehole 12 and the Z3 negative-pressure borehole 12, then the grouting of the b grouting section 10A is completed.

[0079] S7. Move the first rubber water stop of the Z2 positive-pressure borehole 11 to the top of the c grouting section 10A. At the same time, move the second rubber water stops of the Z1 negative-pressure borehole 12 and the Z3 negative-pressure borehole 12 to the same depth as the first rubber water stop. And ensure tight fixation of the first rubber water stop, the second rubber water stop and the borehole wall by injecting water.

[0080] S8. Inject grout into the c grouting section 10A of the Z2 positive-pressure borehole 11 through the grout pump 30. At the same time, pump water out of the plugged sections 10B of the Z1 negative-pressure borehole 12 and the Z3 negative-pressure borehole 12 through the water pump 40 and the air extraction pump 50. After the water in the borehole is pumped dry, continue to extract air. If there is no water in the plugged sections 10B of the Z1 negative-pressure borehole 12 and the Z3 negative-pressure borehole 12, directly extract air through the air extraction pump 50. Continuous air extraction will continuously create negative pressure in the borehole, and the negative pressure will be conducted to the c grouting section 10A of the Z2 positive-pressure borehole 11 through the fracture network, inducing the grout to spread towards the Z1 negative-pressure borehole 12 and the Z3 negative-pressure borehole 12.

[0081] S9. When the uppermost c grouting section 10A of the Z2 positive-pressure borehole 11 reaches the designed grouting pressure, stop the grouting of the c grouting section 10A of the Z2 positive-pressure borehole 11. At the same time, stop the water pumping and air extraction of the Z1 negative-pressure borehole 12 and the Z3 negative-pressure borehole 12, then the grouting of the c grouting section 10A is completed.

[0082] S10. After the full-hole grouting of the Z2 positive-pressure borehole 11 is completed, ream the Z1 negative-pressure borehole 12 and the Z3 negative-pressure borehole 12, and use the borehole crosshole CT method to inspect the grouting effect. If weak positions in the grouting are found, supplementary grouting can be carried out using the Z1 negative-pressure borehole 12 or the Z3 negative-pressure borehole 12.

[0083] S11. After passing the inspection and meeting the design requirements, grout sealing is performed on all the negative-pressure boreholes 12 to avoid the occurrence of the phenomenon that potential boreholes serve as seepage channels.

[0084] The method proposed by the present invention can not only control the occurrence of the phenomenon of preferential flow in which most of the grout diffuses over a long distance in several wide fissures, so that the grout diffusion is more uniform; but also increase the effective diffusion radius of the grout and reduce the project cost.

[0085] A grouting system 100 according to a second aspect of the present invention includes:

[0086] A plurality of boreholes opened on the grouting curtain line, including positive-pressure boreholes 11 and negative-pressure boreholes 12, wherein the positive-pressure boreholes 11 and the negative-pressure boreholes 12 are alternately arranged in sequence;

[0087] Sealing plugs 20 are installed in the positive-pressure boreholes 11 and the negative-pressure boreholes 12 adjacent to the positive-pressure boreholes 11. Among them, the lower end part of the sealing plug 20 and its corresponding positive-pressure borehole 11 form a grouting section 10A, and the lower end part of the sealing plug 20 and its corresponding negative-pressure borehole 12 form a plugging section 10B;

[0088] A grouting pump 30, one end of which is connected to an external grout source, and the other end of which is connected to the grouting section 10A;

[0089] A water pump 40 having a water pumping port, and the water pumping port is connected to the plugging section 10B; and

[0090] An air extraction pump 50 having an air extraction port, and the air extraction port is connected to the plugging section 10B;

[0091] That is to say, a plurality of drill holes are opened on the grouting curtain line. The drill holes include positive-pressure drill holes 11 and negative-pressure drill holes 12, and the positive-pressure drill holes 11 and the negative-pressure drill holes 12 are arranged alternately in sequence. Among them, the positive-pressure drill holes 11 are configured to grout into the drill holes, and the negative-pressure drill holes 12 are configured to pump water and air out of the drill holes; the positive-pressure drill holes 11 are divided into a plurality of grouting sections 10A, and a sealing plug 20 is arranged at the upper end of the grouting section 10A closest to the lower end of the positive-pressure drill hole 11. Similarly, the two adjacent negative-pressure drill holes 12 are blocked with the sealing plug 20 to form a blocking section 10B; the grouting pump 30 grouts into the grouting section 10A at the lowermost end of the positive-pressure drill hole 11, and at the same time, the water pump 40 and the air pump 50 pump water and air out of the blocking sections 10B of the two adjacent negative-pressure drill holes 12. A negative pressure is continuously formed in the blocking section 10B, and the negative pressure will be conducted to the grouting section 10A of the positive-pressure drill hole 11 through the fracture network, inducing the grout to spread to the two adjacent negative-pressure drill holes 12; when the grouting pressure of the grouting section 10A of the positive-pressure drill hole 11 reaches the designed grouting pressure, stop grouting into the grouting section 10A of the positive-pressure drill hole 11, and at the same time, stop pumping water and air out of the blocking sections 10B of the two adjacent negative-pressure drill holes 12 to complete the grouting of one grouting section 10A; repeat the above grouting steps, and grout the positive-pressure drill hole 11 from bottom to top in sequence until the grouting of the entire positive-pressure drill hole 11 is completed.

[0092] The grouting system 100 can not only effectively control the deviation flow effect of the grout diffusion in the rock mass fractures, make the grout diffusion more uniform, but also increase the effective diffusion radius of the grout, change the original "hole-by-hole grouting" into "alternate-hole grouting", greatly improving the grouting efficiency and effect while saving a large amount of project costs and construction periods.

[0093] In an example of the present invention, the sealing plugs 20 in the positive-pressure drill holes 11 and the sealing plugs 20 in the two adjacent negative-pressure drill holes 12 are located at the same depth position, so that the grouting section 10A can effectively induce the grout to spread to the two adjacent negative-pressure drill holes 12, making the grout diffusion more uniform.

[0094] In an example of the present invention, the grouting pressure injected by the grouting pump 30 into the grouting section 10A is less than or equal to the negative pressure formed by the water pump 40 and the air pump 50 in the blocking section 10B, that is, the continuously formed negative pressure in the blocking section 10B can be conducted to the grouting section 10A of the positive-pressure drill hole 11 through the fracture network, inducing the grout to spread to the two adjacent negative-pressure drill holes 12.

[0095] The exemplary embodiments of the grouting method and the grouting system 100 proposed by the present invention have been described in detail above with reference to the preferred embodiments. However, those skilled in the art can understand that, without departing from the concept of the present invention, various modifications and variations can be made to the above specific embodiments, and various combinations of the technical features and structures proposed by the present invention can be made without exceeding the protection scope of the present invention. The protection scope of the present invention is determined by the appended claims.

Claims

1. A grouting method, characterized in that, It includes the following steps: S10: Open a plurality of drill holes (10) on the grouting curtain line. The drill holes (10) include positive-pressure drill holes (11) and negative-pressure drill holes (12), and the positive-pressure drill holes (11) and the negative-pressure drill holes (12) are arranged alternately in sequence. Among them, the positive-pressure drill holes (11) are configured to grout into the drill holes (10), and the negative-pressure drill holes (12) are configured to pump water and air out of the drill holes (10); S20: Divide the positive-pressure drill holes (11) into a plurality of grouting sections (10A), and arrange a sealing plug (20) at the upper end of the grouting section (10A) closest to the bottom end of the positive-pressure drill hole (11). Similarly, use the sealing plug (20) to block the adjacent two negative-pressure drill holes (12) to form a blocked section (10B); among them, the sealing plugs (20) in the positive-pressure drill holes (11) and the sealing plugs (20) in the adjacent two negative-pressure drill holes (12) are located at the same depth position; S30: Grout into the grouting section (10A) at the bottom end of the positive-pressure drill hole (11), and at the same time pump water and air out of the blocked sections (10B) of the adjacent two negative-pressure drill holes (12), continuously form negative pressure in the blocked sections (10B), and the negative pressure will be conducted to the grouting section (10A) of the positive-pressure drill hole (11) through the fracture network, inducing the grout to spread to the adjacent two negative-pressure drill holes (12); among them, the grouting pressure of the grouting section (10A) into the positive-pressure drill hole (11) is less than or equal to the negative pressure of the blocked section (10B) in the negative-pressure drill hole (12); S40: When the grouting section (10A) of the positive-pressure drill hole (11) reaches the designed grouting pressure, stop grouting into the grouting section (10A) of the positive-pressure drill hole (11), and at the same time stop pumping water and air out of the blocked sections (10B) of the adjacent two negative-pressure drill holes (12), and complete the grouting of one grouting section (10A); S50: Repeat steps S20 to S40, grout the positive-pressure drill holes (11) from bottom to top in sequence until the entire positive-pressure drill hole (11) is grouted, and inspect the grouting effect of the positive-pressure drill hole (11). The inspection of the grouting effect includes: using the negative-pressure drill hole (12) as the inspection drill hole of the positive-pressure drill hole (11). When a weak position in the grouting of the positive-pressure drill hole (11) is found, supplementary grouting is carried out into the positive-pressure drill hole (11) through the negative-pressure drill hole (12).

2. The grouting method according to claim 1, characterized in that, After step S50, it further includes: After it is inspected that the grouting of the positive-pressure drill hole (11) meets the design requirements, grout and block the negative-pressure drill hole (12) to eliminate the hidden danger of the negative-pressure drill hole (12) as a seepage channel.

3. The grouting method according to claim 2, characterized in that, The grouting liquid used for grouting and blocking the negative-pressure drill hole (12) is a double-fluid slurry of cement and water glass.

4. The grouting method according to claim 1, characterized in that, In step S20, the depth of each grouting section (10A) is 15 m ~20 m .

5. A grouting system using the grouting method according to any one of claims 1 to 4, characterized in that, It includes: A plurality of drill holes (10) opened on the grouting curtain line, including positive-pressure drill holes (11) and negative-pressure drill holes (12), among which the positive-pressure drill holes (11) and the negative-pressure drill holes (12) are arranged alternately in sequence; Sealing plug (20), installed in the positive pressure drilling hole (11) and the negative pressure drilling hole (12) adjacent to the positive pressure drilling hole (11), wherein the lower end portion of the sealing plug (20) and its corresponding positive pressure drilling hole (11) forms a grouting section (10A), and the lower end portion of the sealing plug (20) and its corresponding negative pressure drilling hole (12) forms a plugging section (10B); Grouting pump (30), one end of which is connected to an external slurry source, and the other end of which is connected to the grouting section (10A); Water pump (40), having a water pumping port, and the water pumping port is connected to the plugging section (10B); and Air extraction pump (50), having an air extraction port, and the air extraction port is connected to the plugging section (10B).

6. The grouting system according to claim 5, characterized in that, The sealing plugs (20) in the positive pressure drilling hole (11) and the sealing plugs (20) in the two adjacent negative pressure drilling holes (12) are located at the same depth position.

7. The grouting system according to claim 5, characterized in that, The grouting pressure injected into the grouting section (10A) by the grouting pump (30) is less than or equal to the negative pressure formed by the water pump (40) and the air extraction pump (50) in the plugging section (10B).

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