A method of grouting for underground high pressure tunnels
By embedding multiple grouting pipes in the grouting hole and injecting quick-drying cement and expansive mortar in sections, the problem of grout leakage in waterway chemical grouting was solved, thus ensuring the safety and stability of the high-pressure tunnel.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- ENG CONSTR MANAGEMENT BRANCH OF CHINA SOUTHERN POWERGRID POWER GENERATION CO LTD
- Filing Date
- 2023-04-13
- Publication Date
- 2026-06-23
AI Technical Summary
In existing technologies, chemical grouting of waterways has the problem of incomplete sealing of gaps, which leads to grout leakage and seepage, affecting the quality and efficiency of tunnel anti-seepage construction. In addition, chemical grout has low viscosity and high fluidity, making it difficult to seal tiny gaps.
The method involves embedding multiple grouting pipes inside the hole to be grouted, injecting quick-drying cement into the hole opening section through the grouting pipes, injecting mortar with expansion and water absorption into the sealing section, and injecting the grouting liquid into the grouting section. Epoxy mortar is used during the segmented grouting process to ensure sealing and stability.
It improves the safety and stability of tunnel grouting, prevents grout leakage, simplifies the grouting process, and ensures construction quality and efficiency.
Smart Images
Figure CN116537741B_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of tunnel grouting technology, and in particular to a method for grouting underground high-pressure tunnels. Background Technology
[0002] In the field of hydropower and water conservancy projects, there are large-scale underground cavern complexes, especially pumped storage power stations. Their water conveyance systems are long, geologically complex, and have large head differences. The highest grouting pressure in the waterways has reached 10 MPa. After the concrete lining of the water conveyance system is completed, the surrounding rock needs to be consolidated and grouted. Cement grouting is performed first, followed by chemical grouting reinforcement to improve the integrity and impermeability of the surrounding rock and ensure the safe operation of the high-pressure waterway. Currently, the sealing method used for chemical grouting in waterways has gaps. Moreover, because chemical grout has low viscosity, good fluidity, and strong injectability, it can be injected into gaps smaller than 0.1 mm. This means that even tiny gaps in the sealing section at the orifice can cause grout to seep out and leak, leading to interruption of grouting operations. This has a significant impact on the quality of tunnel seepage prevention construction, increases the construction period, reduces efficiency, and deteriorates the air quality at the construction site. Summary of the Invention
[0003] The present invention aims to solve at least one of the technical problems existing in the prior art or related art.
[0004] Therefore, the present invention provides a grouting method for underground high-pressure tunnels, comprising:
[0005] Embed the grouting pipe into the hole to be grouted;
[0006] Quick-drying cement is injected into the opening section of the hole to be grouted through the grouting pipe.
[0007] Grout with expansive and water-absorbing properties is injected into the closed section of the hole to be grouted through the grouting pipe;
[0008] Grout is injected into the grouting section of the hole through the grouting pipe.
[0009] In one feasible implementation, embedding the grouting pipe in the hole to be grouted includes:
[0010] At least four grouting pipes are buried in the hole to be grouted.
[0011] In one feasible implementation, embedding the grouting pipe into the hole to be grouted includes:
[0012] A first grouting pipe is embedded in the hole to be grouted, with the end of the first grouting pipe extending to the bottom of the grouting section;
[0013] A second grouting pipe is embedded in the hole to be grouted, with the end of the second grouting pipe extending to the top of the grouting section;
[0014] A third grouting pipe is embedded in the hole to be grouted, with the end of the third grouting pipe extending to the bottom of the closed section;
[0015] A fourth grouting pipe is embedded in the hole to be grouted, with the end of the fourth grouting pipe extending to the top of the closed section.
[0016] In one feasible implementation, the step of embedding the grouting pipe in the hole to be grouted further includes:
[0017] Grouting pipes are distinguished by marking the top of the pipe.
[0018] In one feasible implementation, embedding a grouting pipe into the hole to be grouted further includes:
[0019] Fix the grouting pipe at the opening of the hole to be grouted.
[0020] In one feasible implementation, the step of injecting quick-drying cement into the orifice section of the hole to be grouted through the grouting pipe further includes:
[0021] The depth of the orifice section is 5–25 cm.
[0022] In one feasible implementation, the injection of expansive and absorbent mortar into the sealed section of the hole to be grouted via the grouting pipe further includes:
[0023] After the grouting pipe used for venting returns to its original state, the process ends with the injection of slurry with expansive and water-absorbing properties into the sealed section of the hole to be grouted.
[0024] In one feasible implementation, the step of injecting the grouting fluid into the grouting section of the hole to be grouted through the grouting pipe further includes:
[0025] After the orifice section and the sealing section are tightly sealed, the action of injecting the grout to be injected into the grouting section of the hole to be grouted through the grouting pipe begins;
[0026] After the grouting pipe used for venting returns to its original state, the action of injecting the grouting liquid into the closed section of the hole to be grouted through the grouting pipe ends.
[0027] In one feasible implementation, it further includes:
[0028] After the grouting process is completed, the grouting pipe that exposes the opening of the hole to be grouted is cut off.
[0029] In one feasible implementation, it further includes:
[0030] After the grouting pipe that exposes the opening of the hole to be grouted is removed, the opening of the hole to be grouted is smoothed with mortar that has expansion and water absorption properties.
[0031] Compared with the prior art, the present invention has at least the following beneficial effects: The underground tunnel grouting method provided in this application includes burying a grouting pipe in the hole to be grouted. In this step, all the grouting pipes needed in the entire grouting process need to be buried in the hole in advance to avoid repeated burying of pipes in subsequent steps, which simplifies the grouting process. Quick-drying cement is injected into the opening section of the hole through the grouting pipe. Combined with the rapid agglomeration characteristics of quick-drying cement, a sealing layer can be formed at the opening of the hole under high pressure, providing conditions for subsequent grouting. Mortar with expansion and water absorption properties is injected into the sealed section of the hole through the grouting pipe. While cement has the advantage of rapid agglomeration, it can crack during drying shrinkage. Directly injecting chemical grout can lead to problems such as grout leakage. Therefore, a sealing section is added below the orifice section, and mortar with expansive and water-absorbing properties is injected. The mortar used in this step should also be fluid before it sets. Specifically, epoxy mortar can be used. The grout is injected into the grouting section of the hole through the grouting pipe. This step should be carried out after the hardness of the mortar in the sealing section reaches the required threshold. At this time, the cement or mortar in the orifice section and the sealing section ensure that the grout does not overflow, thus improving the safety and stability of production. Attached Figure Description
[0032] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:
[0033] Figure 1 A schematic flowchart illustrating the steps of an underground high-pressure tunnel grouting method according to an embodiment of this application;
[0034] Figure 2 A schematic cross-sectional view of underground high-pressure tunnel grouting according to an embodiment of this application.
[0035] in, Figure 2 The correspondence between the reference numerals and component names in the attached drawings is as follows:
[0036] 101. Orifice section; 102. Sealed section; 103. Grouting section; 104. First grouting pipe; 105. Second grouting pipe; 103. Third grouting pipe; 104. Fourth grouting pipe. Detailed Implementation
[0037] To better understand the above technical solutions, the technical solutions of the embodiments of this application will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the embodiments of this application and the specific features in the embodiments are detailed descriptions of the technical solutions of the embodiments of this application, rather than limitations on the technical solutions of this application. In the absence of conflict, the embodiments of this application and the technical features in the embodiments can be combined with each other.
[0038] like Figure 1-2 As shown, according to an embodiment of this application, a grouting method for underground high-pressure tunnels is proposed, comprising:
[0039] Step 100: Embed the grouting pipe into the hole to be grouted;
[0040] Step 200: Inject quick-drying cement into the orifice section 101 of the hole to be grouted through the grouting pipe;
[0041] Step 300: Inject mortar with expansive and water-absorbing properties into the closed section 102 of the hole to be grouted through the grouting pipe;
[0042] Step 400: Inject the grouting liquid into the grouting section 103 of the hole to be grouted through the grouting pipe.
[0043] The underground tunnel grouting method provided in this application divides the grouting hole into three sections, from top to bottom: the orifice section 101, the sealing section 102, and the grouting section 103. The orifice section 101 is used for initial sealing of the grouting hole, the sealing section 102 is used to reinforce the sealing, and the grouting section 103 is used to inject the grout. The specific steps are as follows: Step 100: Bury a grouting pipe into the grouting hole. In this step, all grouting pipes needed throughout the grouting process must be buried in the grouting hole in advance to avoid repeated pipe burial in subsequent steps, thus simplifying the grouting process. Step 200: Inject quick-drying cement into the orifice section 101 of the grouting hole through the grouting pipe. Combined with the rapid agglomeration characteristic of quick-drying cement, a sealing layer can be formed at the orifice of the grouting hole under high pressure, providing conditions for subsequent grouting. In step 300, mortar with expansive and water-absorbing properties is injected into the sealed section 102 of the hole to be grouted through the grouting pipe. Although quick-drying cement has the advantage of rapid agglomeration, it will crack during the drying shrinkage process. If chemical grout is directly injected, it will lead to problems such as grout leakage. Therefore, a sealed section 102 is added below the orifice section 101, and mortar with expansive and water-absorbing properties is injected. The mortar used in this step should also have fluidity when it has not set. Specifically, epoxy mortar can be used. In step 400, the grout to be injected is injected into the grouting section 103 of the hole to be grouted through the grouting pipe. This step should be carried out after the hardness of the mortar in the sealed section 102 reaches the required threshold. At this time, the cement or mortar in the orifice section 101 and the sealed section 102 ensure that the grout to be injected does not overflow, which improves the safety and stability of production.
[0044] like Figure 1 As shown, the step of embedding grouting pipes in the hole to be grouted includes: embedding at least four grouting pipes in the hole to be grouted.
[0045] In this technical solution, embedding grouting pipes in the grouting hole includes using at least four grouting pipes embedded in the grouting hole. When grouting the grouting hole, at least three grouting pipes are needed to grout the three sections of the grouting hole respectively, and one grouting pipe is used as an air outlet pipe. When the grouting pressure is too high, additional grouting pipes can be added according to the actual situation.
[0046] like Figure 2 As shown, the step of embedding grouting pipes in the grouting hole includes: embedding a first grouting pipe 104 in the grouting hole, with the end of the first grouting pipe 104 extending to the bottom of the grouting section 103; embedding a second grouting pipe 105 in the grouting hole, with the end of the second grouting pipe 105 extending to the top of the grouting section 103; embedding a third grouting pipe 103 in the grouting hole, with the end of the third grouting pipe 103 extending to the bottom of the closed section 102; and embedding a fourth grouting pipe 104 in the grouting hole, with the end of the fourth grouting pipe 104 extending to the top of the closed section 102.
[0047] In this technical solution, the third grouting pipe 103 extends to the bottom of the closed section 102, and the fourth grouting pipe 104 extends to the top of the closed section 102. When sealing the orifice section 101, quick-drying cement is injected into the orifice section 101 through the fourth grouting pipe 104. When the hardness of the quick-drying cement reaches the required level, the closed section 102 is grouted through the third grouting pipe 103. When the hardness of the mortar in the closed section 102 reaches the required level, the grouting section 103 is grouted through the second grouting pipe 105, and air is released through the first grouting pipe 104 until the grouting is completed.
[0048] like Figure 2 As shown, the method of embedding the grouting pipe in the hole to be grouted also includes: marking the top of the grouting pipe to distinguish the grouting pipe.
[0049] In this technical solution, the top of the grouting pipe is marked to distinguish the grouting pipes, so as to avoid workers using the wrong grouting pipe when grouting, which would affect the construction progress. In the specific operation, the grouting pipes can be wrapped with different colored tapes to achieve different grouting pipe styles.
[0050] like Figure 2 As shown, embedding the grouting pipe in the hole to be grouted also includes fixing the grouting pipe at the opening of the hole to be grouted.
[0051] In this technical solution, the grouting pipe should be fixed at the orifice section 101 before grouting to prevent the grouting pipe from falling or tilting, thereby reducing the probability of accidents during the implementation of this invention. In the specific construction process, non-woven fabric or other materials can be used to fix the grouting pipe.
[0052] like Figure 2 As shown, the step of injecting quick-drying cement into the orifice section 101 of the hole to be grouted through the grouting pipe further includes: the orifice section 101 having a depth of 5 to 25 cm.
[0053] In this technical solution, the depth of the orifice section 101 is 5-25cm. If it is less than 5cm, the quick-drying cement will not be able to seal the hole and will easily fall off under high pressure.
[0054] like Figure 2 As shown, the process of injecting mortar with expansive and water-absorbing properties into the closed section 102 of the hole to be grouted through the grouting pipe further includes: after the grouting pipe for venting air returns to its original state, the process of injecting mortar with expansive and water-absorbing properties into the closed section 102 of the hole to be grouted through the grouting pipe ends.
[0055] In this technical solution, after the grouting pipe used for venting backflows, the action of injecting slurry with expansive and water-absorbing properties into the sealed section 102 of the hole to be grouted through the grouting pipe ends. This step ensures that the slurry can fill the sealed section, ensuring that the sealing section 102 and the hole opening section 101 will not be incompletely filled, resulting in chemical slurry backflow to the ground. In the actual construction process, under the action of high pressure in the hole to be grouted, when grouting the sealed section 102, the gas and slurry are discharged through the second grouting pipe 105. Therefore, this step specifically means that when the second grouting pipe 105 backflows, the grouting of the sealed section 102 ends.
[0056] like Figure 2 As shown, the process of injecting the grouting liquid into the grouting section 103 of the hole to be grouted through the grouting pipe further includes: after the orifice section 101 and the sealing section 102 are tightly sealed, the process of injecting the grouting liquid into the grouting section 103 of the hole to be grouted through the grouting pipe begins; after the grouting pipe used for venting backflows, the process of injecting the grouting liquid into the sealing section 102 of the hole to be grouted through the grouting pipe ends.
[0057] In this technical solution, after the orifice section 101 and the sealing section 102 are tightly bonded, the action of injecting the grout to be injected into the grouting section 103 of the hole to be grouted through the grouting pipe begins. After the grouting pipe used for venting backflows, the action of injecting the grout to be injected into the sealing section 102 of the hole to be grouted through the grouting pipe ends. In actual construction, it is necessary to wait for the quick-drying cement of the orifice section 101 and the epoxy mortar of the sealing section to be tightly bonded before injecting the grout to be injected into the grouting section 103. The grouting action ends when backflow occurs at the end of the first grouting pipe 104.
[0058] like Figure 2 As shown, it also includes: after the action of injecting the grouting liquid into the closed section 102 of the hole to be grouted through the grouting pipe is completed, the grouting pipe exposed at the opening of the hole to be grouted is cut off.
[0059] In this technical solution, after the grouting liquid is injected into the closed section 102 of the hole to be grouted through the grouting pipe, the grouting pipe exposed at the hole opening is cut off. In actual operation, the grouting pipe usually extends out of the hole opening to facilitate construction. After grouting is completed, the grouting pipe extending out of the hole opening should be cut off along the surface of the quick-drying cement to avoid accidents caused by the protruding grouting pipe.
[0060] like Figure 2 As shown, it also includes: after the action of cutting off the grouting pipe that exposes the opening of the hole to be grouted is completed, the opening of the hole to be grouted is smoothed with mortar that has expansion and water absorption properties.
[0061] In this technical solution, after the grouting pipe exposed at the opening of the hole to be grouted is removed, the opening of the hole to be grouted is smoothed with mortar that has expansion and water absorption properties. When the opening section 101 is sealed with quick-drying cement, cracks will appear on the upper surface of the opening section 101 due to the shrinkage of the quick-drying cement. Therefore, after the excess part of the grouting pipe is removed, it is smoothed again to increase the stability of high-pressure tunnel grouting.
[0062] In this invention, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance; the term "multiple" refers to two or more unless otherwise explicitly defined. The terms "install," "connect," "link," and "fix" should be interpreted broadly. For example, "connect" can be a fixed connection, a detachable connection, or an integral connection; "link" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.
[0063] In the description of this invention, it should be understood that the terms "upper," "lower," "left," "right," "front," "rear," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or unit referred to must have a specific orientation or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.
[0064] In the description of this specification, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.
[0065] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.
Claims
1. A grouting method for underground high-pressure tunnels, characterized in that, include: Embed the grouting pipe into the hole to be grouted; Quick-drying cement is injected into the opening section of the hole to be grouted through the grouting pipe. Grout with expansive and water-absorbing properties is injected into the closed section of the hole to be grouted through the grouting pipe; The grouting fluid is injected into the grouting section of the hole to be grouted through the grouting pipe; The embedding of the grouting pipe in the hole to be grouted includes: A first grouting pipe is embedded in the hole to be grouted, with the end of the first grouting pipe extending to the bottom of the grouting section; A second grouting pipe is embedded in the hole to be grouted, with the end of the second grouting pipe extending to the top of the grouting section; A third grouting pipe is embedded in the hole to be grouted, with the end of the third grouting pipe extending to the bottom of the closed section; A fourth grouting pipe is embedded in the hole to be grouted, with the end of the fourth grouting pipe extending to the top of the closed section; The process of injecting quick-drying cement into the orifice section of the hole to be grouted through the grouting pipe includes: The depth of the orifice section is 5~25cm; The process of injecting mortar with expansive and water-absorbing properties into the sealed section of the hole to be grouted through the grouting pipe includes: After the grouting pipe used for venting is reversed, the process ends by injecting mortar with expansive and water-absorbing properties into the closed section of the hole to be grouted through the grouting pipe. The process of injecting the grouting fluid into the grouting section of the hole through the grouting pipe includes: After the orifice section and the sealing section are tightly sealed, the action of injecting the grout to be injected into the grouting section of the hole to be grouted through the grouting pipe begins; After the grouting pipe used for venting is reversed, the action of injecting the grouting liquid into the grouting section of the hole to be grouted through the grouting pipe ends. After the action of injecting the grouting liquid into the grouting section of the hole to be grouted through the grouting pipe is completed, the grouting pipe exposed at the opening of the hole to be grouted is cut off; After the grouting pipe that exposes the opening of the hole to be grouted is removed, the opening of the hole to be grouted is smoothed with mortar that has expansion and water absorption properties.
2. The underground high-pressure tunnel grouting method according to claim 1, characterized in that, The process of embedding the grouting pipe in the hole to be grouted includes: At least four grouting pipes are buried in the hole to be grouted.
3. The underground high-pressure tunnel grouting method according to claim 1, characterized in that, The process of embedding the grouting pipe in the hole to be grouted also includes: Grouting pipes are distinguished by marking the top of the pipe.
4. The underground high-pressure tunnel grouting method according to claim 1, characterized in that, The process of embedding a grouting pipe into the hole to be grouted also includes: Fix the grouting pipe at the opening of the hole to be grouted.