Water control method for tunnel construction under ultrahigh-pressure water-rich condition

Abstract

The invention relates to the field of tunnel water control, in particular to a water control method for tunnel construction under the ultrahigh-pressure water-rich condition. A water control method for tunnel construction under the ultrahigh-pressure water-rich condition comprises the following steps that firstly, grouting drill holes are formed in areas which are prone to deformation and holes, plugging grouting is conducted, and radial local grouting reinforcement is conducted; 2, checking is carried out after treatment, and the above steps are repeated for treatment of unqualified products; the grouting adopts a special water control grouting material which comprises cement, an inorganic admixture, a water reducing agent, water, waste glass powder, pineapple leaf fibers and pullulan. The water control method is suitable for ultrahigh-pressure water-rich conditions, and the water control effect can be remarkably improved.

Description

Technical Field

[0001] The present application relates to the field of tunnel water control, and more specifically, it relates to a water control method for tunnel construction under ultra-high pressure and rich water conditions. Background Art

[0002] During the construction of tunnel projects, especially in areas with complex geological conditions and abundant groundwater, water control has always been a core problem that restricts the progress and safety of the project. In particular, under ultra-high pressure and rich water conditions, the risk of water inrush during tunnel excavation is particularly prominent, which is not only a major obstacle in the construction process, but also a key factor that poses a major threat to the safety and stability of the tunnel structure.

[0003] The main reasons why water control has become an important part of tunnel construction include the following two points: First of all, water control is crucial to ensuring construction safety. Under ultra-high pressure and rich water conditions, if groundwater is not effectively controlled, water inrush accidents are very likely to occur during tunnel excavation, which will not only cause damage to construction equipment and flooding of tunnels, but also pose a serious threat to the lives of construction workers. Therefore, water control has become a prerequisite for ensuring the safe and smooth progress of tunnel construction.

[0004] Secondly, water control is of great significance to improving the quality of the project. During tunnel construction, if water damage is not effectively controlled, groundwater will cause continuous erosion of the tunnel structure, leading to quality problems such as lining cracks, tunnel bottom hanging, bottom paving or invert broken. These quality problems will not only reduce the service life of the tunnel, but also pose a potential threat to the safe operation of the tunnel. Therefore, water control plays an irreplaceable role in improving the quality of tunnel projects and ensuring the safety and stability of tunnel structures.

[0005] Traditional water control methods, such as drainage wells and drainage ditches, often fail to achieve ideal water control effects under ultra-high pressure and rich water conditions. This is because these methods can usually only dredge surface water or shallow groundwater, but are helpless against deep, high-pressure groundwater. In addition, these methods may also cause instability in the strata around the tunnel, further exacerbating construction risks. Therefore, there is still room for improvement. Summary of the invention

[0006] In order to more effectively control water, the present application provides a method for controlling water in tunnel construction under ultra-high pressure and water-rich conditions.

[0007] In the first aspect, the present application provides a water control grouting material, which adopts the following technical solution: A water control grouting material comprises the following raw materials in parts by weight: 100 parts of cement, 15-25 parts of inorganic admixtures, 0.1-2 parts of water reducers, 55-65 parts of water, 10-20 parts of waste glass powder, 5-10 parts of pineapple leaf fibers, and 1-3 parts of pullulan.

[0008] The micro-base filling effect of waste glass powder can reduce the interconnected pore channels inside the water-control grouting material, reduce the pores inside the system, and improve the compactness of the internal structure of the water-control grouting material, thereby further improving the impermeability of the water-control grouting material. The addition of pineapple leaf fiber can significantly improve the tensile strength and crack resistance of the grouting material and enhance the overall stability of the grouting body. The fiber morphology and distribution of pineapple leaf fiber can improve the fluidity of the grouting material to a certain extent, making it easier to grout under complex geological conditions. The addition of pullulan can significantly improve the initial fluidity of the grouting material and maintain good flow stability, which helps the grouting material to be evenly distributed in cracks and pores. The water retention of pullulan helps to reduce the water loss of the grouting material during the curing process, thereby indirectly improving the impermeability and overall strength.

[0009] By adopting the above technical solution, with the cooperation of waste glass powder, pineapple leaf fiber and pullulan, part of the waste glass powder will be attached to the structure of pineapple leaf fiber, alleviating the phenomenon of excessive aggregation of waste glass powder in the system. The pullulan dissolved in the system cooperates with the pineapple leaf fiber and the waste glass powder attached to the pineapple leaf fiber to form a porous film on the surface of the pineapple leaf fiber and the waste glass powder attached to the pineapple leaf fiber, making the waste glass powder more firmly combined with the pineapple leaf fiber. This special structure can play a long-term effect in the system and enhance the strength, impermeability and fluidity of the water control grouting material.

[0010] The water control grouting material provided in the present application has good permeability, adhesion and impermeability, ensuring that the grouting body can tightly fill the tiny cracks in the tunnel structure, forming an effective waterproof barrier and enhancing the water control effect.

[0011] Preferably, in terms of weight, the waste glass powder is 12-15 parts, the pineapple leaf fiber is 6-8 parts, and the pullulan is 1.5-2.0 parts.

[0012] By adopting the above technical solution, the amount of waste glass powder, pineapple leaf fiber, and pullulan in the system is further limited, which can significantly optimize the performance of water control grouting materials. An appropriate amount of waste glass powder is combined with pineapple leaf fiber to reduce porosity, enhance density, and improve impermeability; pineapple leaf fiber enhances tensile strength and fluidity; pullulan improves fluidity and maintains stability, reduces water loss, and indirectly enhances impermeability and strength. The three are synergistically combined and exert long-term effects, ensuring that the grouting material tightly fills the cracks, forming a waterproof barrier, and significantly improving the water control effect.

[0013] Preferably, the particle size of the waste glass powder is 15-25 μm.

[0014] By adopting the above technical solution, the particle size of the waste glass powder is further limited, which helps to reduce the friction resistance of the waste glass powder in the system, thereby improving the fluidity of the water control grouting material.

[0015] Preferably, the method for preparing the waste glass powder comprises the following steps: washing and air-drying the waste glass, initially crushing it, ball-milling it, and sieving it to obtain the waste glass powder.

[0016] Preferably, the inorganic admixture includes a mixture of one or more of fly ash, coal gangue and silicon powder.

[0017] Preferably, the inorganic admixtures are coal ash and coal gangue, and the weight ratio of coal ash to coal gangue is (0.8-1.2): (0.8-1.2).

[0018] In a second aspect, the present application provides a method for preparing a water-control grouting material, which adopts the following technical solution: A method for preparing a water-control grouting material comprises the following steps: stirring and mixing all raw materials until they are uniform to obtain the water-control grouting material.

[0019] The preparation method of the water-control grouting material provided in the present application is simple, fast and low-cost, and is suitable for industry promotion and practical application.

[0020] In a third aspect, the present application provides a water control method for tunnel construction under ultra-high pressure and rich water conditions, which adopts the following technical solution: A water control method for tunnel construction under ultra-high pressure and rich water conditions, comprising the following steps: Step 1: For areas prone to deformation and holes, set up grouting drilling and carry out plugging grouting respectively, and carry out radial local grouting reinforcement; Step 2: Check after treatment, and repeat the above steps for those that fail the inspection; This application adopts grouting reinforcement to control water. By injecting high-performance water-control grouting materials around and inside the tunnel, a continuous grouting body is formed, thereby effectively blocking the leakage path of groundwater. It can not only significantly improve the waterproof performance of the tunnel, but also enhance the overall stability of the tunnel structure, providing additional safety guarantees for construction. This method can effectively reduce the risk of water inrush during tunnel construction, improve construction efficiency, and ensure the safety and stability of the tunnel structure.

[0021] The water control method provided in this application is not only applicable to tunnel construction under ultra-high pressure and rich water conditions, but also can provide useful reference and reference for tunnel water control under other similar geological conditions. Therefore, the research and development and application of this method has important engineering significance and social value.

[0022] In summary, this application has the following beneficial effects: 1. Since this application adopts the grouting reinforcement water control method, a continuous grouting barrier is constructed by injecting high-performance water control grouting materials around and inside the tunnel. This method can effectively cut off the groundwater leakage channel, not only greatly improve the waterproof performance of the tunnel, but also greatly enhance the overall stability of the tunnel structure. It can effectively reduce the threat of water inrush during tunnel excavation, accelerate the construction progress, and ensure the safety and stability of the tunnel structure.

[0023] 2. Waste glass powder is used as a micro-base material to effectively reduce the pore channels inside the water-control grouting material and improve its density and impermeability. Pineapple leaf fiber significantly enhances the tensile strength, crack resistance and overall stability of the grouting material, while improving its fluidity, which is convenient for grouting in complex geology. Pullulan not only improves the initial fluidity of the grouting material and maintains flow stability, but also reduces water loss during the curing process through water retention, thereby improving the impermeability and overall strength of the grouting material. The present application preferably uses waste glass powder, pineapple leaf fiber and pullulan to give the water-control grouting material good impermeability, strength and fluidity.

[0024] 3. In this application, waste glass powder, pineapple leaf fiber and pullulan are preferably used to work together to form a special structure in which glass powder is attached to pineapple leaf fiber and pullulan forms a porous film on its surface, thereby enhancing the binding force. This water control grouting material has excellent penetration, bonding and impermeability properties, can effectively fill small cracks in tunnels, build a waterproof barrier, and significantly improve the water control effect and material performance. DETAILED DESCRIPTION

[0025] The present application is further described in detail below with reference to the embodiments.

[0026] The raw materials used in the following examples and comparative examples are all commercially available products. Example

[0027] Example 1 A water control grouting material comprises the following raw materials: cement, inorganic admixture, water reducing agent, water, waste glass powder, pineapple leaf fiber and pullulan.

[0028] The specific amount of each raw material is shown in Table 1.

[0029] The cement is Portland cement PO 42.5R.

[0030] The inorganic admixtures are fly ash and coal gangue, and the weight ratio of fly ash to coal gangue is 1:1.

[0031] The water reducer is a commercially available polycarboxylate water reducer.

[0032] The method for preparing waste glass powder comprises the following steps: Step a: Use clean water to clean commercially available waste glass, and use hot air to dry the water on the surface of the waste glass.

[0033] Step b: Put the waste glass into a crusher for preliminary crushing to facilitate subsequent ball milling.

[0034] Step c: putting the waste glass that has been initially crushed in step b into a ball mill for ball milling.

[0035] Then the waste glass powder with a particle size of 15-25 μm is sieved out.

[0036] The present application also provides a method for preparing a water-control grouting material, and the specific steps are: mixing cement, inorganic admixtures, a water reducer, water, waste glass powder, pineapple leaf fiber, and pullulan, and stirring until uniform to obtain the water-control grouting material.

[0037] The present application also provides a water control method for tunnel construction under ultra-high pressure and rich water conditions, comprising the following steps: Step 1: In a water-rich environment, the initial support shotcrete is washed away during construction, which can easily form cavities. In addition, if the fault rock mass is broken, the initial support steel frame may not be tightly attached to the surrounding rock.

[0038] Therefore, for areas prone to deformation and holes, grouting drilling is set up and sealing grouting is carried out separately to carry out radial local grouting reinforcement.

[0039] Specifically, the depth of the radial local grouting drilling is 4m, and the final hole shall not be less than 42mm, and then the orifice pipe is buried. The orifice pipe adopts a steel flower pipe with a diameter of 42mm and a wall thickness of 3.5mm, and a pipe length of 1m. The orifice pipe should be firmly buried and have good grouting measures.

[0040] The hole mouth should be drilled as close to the steel frame as possible, with an annular spacing of 1.0-1.5m, a longitudinal spacing of 1.2m / ring, and 7 holes per ring. The hole layout can be adjusted appropriately according to the water outlet point and initial support conditions.

[0041] The grouting material used for grouting in step 1 is the above-mentioned water control grouting material.

[0042] Step 2: Inspect after treatment, and repeat the above steps for those that fail the inspection.

[0043] Example 2 A water control grouting material, which is different from Example 1 in that the amount of each raw material and the selection of some raw materials are different, see Table 1 for details.

[0044] The inorganic admixture is fly ash.

[0045] The water reducing agent is sodium lignin sulfonate.

[0046] Example 3 A water control grouting material, which is different from Example 1 in that the amount of each raw material and the selection of some raw materials are different, see Table 1 for details.

[0047] The inorganic admixture is silica fume.

[0048] Example 4 A water control grouting material, which is different from Example 1 in that the amounts of waste glass powder, pineapple leaf fiber, and pullulan are different, and the weight ratios of coal ash and coal gangue are different, as shown in Table 1 for details.

[0049] Example 5 A water control grouting material, which is different from Example 1 in that the amounts of waste glass powder, pineapple leaf fiber, and pullulan are different, and the weight ratios of coal ash and coal gangue are different, as shown in Table 1 for details.

[0050] Table 1 Example 6 A water control grouting material, which is different from Example 1 in that the particle size of the waste glass powder is 150-250 μm.

[0051] Comparative Example Comparative Example 1 A water control grouting material, which is different from Example 1 in that waste glass powder is omitted.

[0052] Comparative Example 2 A water control grouting material, which is different from Example 1 in that pineapple leaf fibers are replaced by jute fibers.

[0053] Comparative Example 3 A water control grouting material, which is different from Example 1 in that pullulan is replaced by xanthan gum.

[0054] Comparative Example 4 A water control grouting material, which is different from Example 1 in that the waste glass powder is 1.8 kg, the pineapple leaf fiber is 15 kg, and the pullulan is 7.5 kg.

[0055] Comparative Example 5 A water control grouting material, which is different from Example 1 in that waste glass powder, pineapple leaf fiber and pullulan are omitted.

[0056] Performance testing 1. Compressive strength: Referring to JC / T 986-2018 "Cement-based Grouting Materials", the compressive strength of the water control grouting materials of Examples 1-6 and Comparative Examples 1-5 was tested, and the 3d compressive strength was recorded in Table 2.

[0057] 2. Impermeability: Referring to JGJ / T70-2009 "Standard for Test Methods for Basic Properties of Building Mortar", the water control grouting materials of Examples 1-6 and Comparative Examples 1-5 were tested for their impermeability, and the impermeability pressure was recorded in Table 2.

[0058] 3. Fluidity: Referring to JC / T 986-2018 "Cement-based Grouting Materials", the 30-min fluidity of the water-control grouting materials of Examples 1-6 and Comparative Examples 1-5 was tested, and the results were recorded in Table 2.

[0059] Table 2 Comparative Example 5 is based on Example 1, omitting the waste glass powder, pineapple leaf fiber, and pullulan, and simulating the commonly used water control grouting materials on the market. Since there are few particles in Comparative Example 5, the fluidity is very good, but the compressive strength is low and the impermeability is poor, and it cannot provide a good water control effect. The water control grouting materials of Examples 1-6 of the present application, although the fluidity is slightly lower than that of Comparative Example 5, are still at a relatively high level, have good fluidity, and can meet the needs of grouting; and they have high compressive strength, good impermeability, and excellent overall performance, which can well reinforce water control.

[0060] Comparative Example 1 is based on Example 1, omitting the waste glass powder; Comparative Examples 2-3 are based on Example 1, replacing pineapple leaf fiber and pullulan with other raw materials; Comparative Example 4 is based on Example 1, changing the specific dosage of waste glass powder, pineapple leaf fiber, and pullulan in the system. According to the test data in Table 2, the destruction of the coordination relationship between waste glass powder, pineapple leaf fiber, and pullulan to varying degrees will have a negative impact on strength, impermeability, and fluidity, so that the water treatment obtained cannot have high fluidity, compressive strength, and impermeability.

[0061] After the waste glass powder is omitted in Comparative Example 1, the fluidity will be higher due to the reduction of particulate matter in the system. However, due to the lack of waste glass powder, it is impossible to form a special structure with pineapple leaf fiber and pullulan. The resulting water control grouting material has large pores and low density, which makes it easy for water to penetrate and the strength is significantly reduced, thus failing to achieve a significant water control effect. Although Example 1 has more particulate matter than Comparative Example 1, the special coordination effect of the three alleviates the effect of particulate matter on fluidity, so that Example 1 can maintain a relatively high fluidity.

[0062] Example 6 is based on Example 1, and uses waste glass powder with a larger particle size specification. According to the test data of Example 1 and Example 6 in Table 2, the fluidity, compressive strength, and anti-seepage pressure of Example 6 all show a downward trend, which is not as good as the effect of Example 1. It shows that if the particle size of the waste glass powder can be further limited, it can have a better coordination effect with pineapple leaf fiber and pullulan in the system, thereby further improving the performance of the water control grouting material and enhancing the water control effect.

[0063] This application adopts grouting reinforcement to control water, and develops a water control grouting material with good impermeability, high compressive strength and good fluidity. During grouting, the water control grouting material can penetrate faster and more widely to reinforce everywhere, and effectively alleviate groundwater leakage, thereby enhancing the water control effect.

[0064] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the present embodiment without any creative contribution as needed, but such modifications are protected by the patent law as long as they are within the scope of the claims of the present application.

Claims

1. A water control grouting material, characterized in that: The raw materials include the following in parts by weight: 100 parts of cement, 15-25 parts of inorganic admixture, 0.1-2 parts of water reducer, 55-65 parts of water, 10-20 parts of waste glass powder, 5-10 parts of pineapple leaf fiber, and 1-3 parts of pullulan.

2. The water control grouting material according to claim 1, characterized in that: In terms of weight, the waste glass powder is 12-15 parts, the pineapple leaf fiber is 6-8 parts, and the pullulan is 1.5-2.0 parts.

3. The water control grouting material according to claim 1, characterized in that: The particle size of the waste glass powder is 15-25 μm.

4. The water control grouting material according to claim 1, characterized in that: The method for preparing the waste glass powder comprises the following steps: washing and air-drying the waste glass, initially crushing the waste glass, ball-milling the waste glass, and sieving the waste glass powder to obtain the waste glass powder.

5. The water control grouting material according to claim 1, characterized in that: The inorganic admixture includes a mixture of one or more of fly ash, coal gangue and silicon powder.

6. The water control grouting material according to claim 5, characterized in that: The inorganic admixtures are coal ash and coal gangue, and the weight ratio of the coal ash to the coal gangue is (0.8-1.2): (0.8-1.2).

7. The method for preparing the water control grouting material according to any one of claims 1 to 6, characterized in that: The method comprises the following steps: all raw materials are stirred and mixed until they are uniform to obtain water control grouting materials.

8. A water control method for tunnel construction under ultra-high pressure and rich water conditions, characterized in that: The following steps are involved: Step 1: For areas prone to deformation and holes, set up grouting drilling and carry out plugging grouting respectively, and carry out radial local grouting reinforcement; Step 2: After treatment, check and repeat the above steps for those that fail the inspection; The grouting material used for grouting in step 1 is the water control grouting material according to any one of claims 1 to 6.

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