Intelligent grouting method based on real-time permeability monitoring

Abstract

The present application relates to the technical field of intelligent grouting, in particular to an intelligent grouting method based on real-time permeability monitoring, comprising: arranging a pressure monitoring array in a grouting area, the pressure monitoring array being electrically connected with a controller; starting grouting, obtaining the time when grout reaches each measuring point; calculating the change of formation permeability; dynamically adjusting grouting parameters according to the change of permeability, the grouting parameters including grouting pressure, water-cement ratio and cement particle size. The present application uses the most suitable grout to achieve the grouting target in the most efficient, economic and safe way, aiming to solve the problems of uneven grouting, poor reinforcement effect and great safety hazards in traditional grouting technology. The present method realizes real-time monitoring of formation permeability coefficient through pressure sensors, and dynamically adjusts grouting parameters based on the change of permeability, ensuring the injection of suitable grout to improve construction quality and efficiency, and further promoting the intelligent development of grouting technology.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of intelligent grouting, in particular to an intelligent grouting method based on real-time permeability monitoring. BACKGROUND

[0002] As one of the core technologies in the fields of geotechnical engineering and civil engineering, grouting technology is to mix specific materials according to a certain proportion to obtain grout, and to forcibly inject the grout into the pores or cracks of the target body (such as loose soil layer, rock fissure, concrete crack, etc.) by using the pressure generated by the grouting pump, and to realize the functions of foundation reinforcement, seepage prevention and leakage plugging, structure reinforcement, etc. through solidification reaction, which plays an irreplaceable role in various types of engineering. Therefore, grouting technology, with its core advantage of "precise improvement of medium performance", guarantees the stability of the structure in foundation reinforcement, and blocks the threat of water damage in engineering seepage prevention, becoming a key means to ensure safety, improve quality and prolong life in modern engineering construction.

[0003] Different strata have different permeabilities, especially when the soil pore structure is uneven or the groundwater flow is unstable, the permeability of the stratum will change dynamically during the grouting construction process. The pre-geological survey at the initial stage of construction can only provide a rough model, and if the permeability of the stratum is not monitored in real time during the grouting construction process, over or under grouting, blind construction, invalid perfusion, and grout waste may occur. In addition, for strata with different permeabilities, appropriate grouting parameters need to be selected for perfusion. Inappropriate grouting parameters may cause grout blockage at the grouting port, incomplete stratum reinforcement, poor reinforcement effect, or environmental damage such as hydraulic fracturing and ground uplift.

[0004] In the field of grouting construction technology, there is no scheme that can monitor the change of stratum permeability in real time and dynamically adjust the grouting parameters based on the change of permeability. The existing technology lacks an intelligent control mechanism for permeability changes. Therefore, how to realize real-time monitoring and parameter adjustment during grouting to ensure the uniformity of grouting, the optimality of reinforcement, and the safety of construction is an important direction for the development of current grouting construction technology. SUMMARY

[0005] The present application aims to overcome the shortcomings of the prior art and provides an intelligent grouting method based on real-time permeability monitoring. The method uses the most suitable grout to achieve the grouting goal in the most efficient, most economical and safest way, and aims to solve the problems of uneven grouting, poor reinforcement effect and high safety risks in traditional grouting technology. The method realizes real-time monitoring of the permeability coefficient of the stratum through a pressure sensor, and dynamically adjusts the grouting parameters based on the change of permeability, ensuring the injection of appropriate grout to improve the construction quality and efficiency, and further promoting the intelligent development of grouting technology.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A smart grouting method based on real-time permeability monitoring includes:

[0008] Step 1: Deploy a pressure monitoring array using pressure sensors in the area to be grouted. The pressure sensors are electrically connected to the controller.

[0009] Step 2: Begin grouting and obtain the time it takes for the grout to reach each measuring point;

[0010] Step 3: Calculate the rate of change of the formation permeability coefficient;

[0011] Step 4: Dynamically adjust the grouting parameters according to the rate of change of the permeability coefficient. The grouting parameters include grouting pressure, water-cement ratio, and cement particle size.

[0012] Furthermore, in step one, the pressure monitoring array is formed by placing a pressure sensor every 10cm in the area to be grouted, and the pressure sensor is a soil pressure cell.

[0013] Furthermore, in step three, the specific process for calculating the rate of change of the formation permeability coefficient is as follows:

[0014] Calculate the first Equivalent permeability coefficient at each measurement point The formula is as follows:

[0015]

[0016] in, The static head of the slurry. The viscosity of the slurry. The density of the slurry, It is the acceleration due to gravity. For the slurry front to reach the first Time at each measurement point From the grouting port to the first The path length of each measurement point on the diffusion principal plane, and the coordinates of the grouting port are... , No. The coordinates of the measurement points are ;

[0017] Calculate the overall regional average permeability coefficient at this moment. The formula is as follows:

[0018]

[0019] in, This represents the total number of measurement points through which the slurry flows at that moment;

[0020] Calculate the rate of change of the permeability coefficient The formula is as follows:

[0021]

[0022] in, This is the difference between the permeability coefficient at this moment and the permeability coefficient at the previous moment;

[0023] The permeability coefficient at the previous moment.

[0024] Furthermore, in step four, the method for dynamically adjusting the grouting parameters based on the rate of change of the permeability coefficient is as follows:

[0025] when Adjust the grouting pressure as needed;

[0026] when Adjust the water-cement ratio as needed;

[0027] when Adjust the cement particle size as needed;

[0028] in, and These are the first and second thresholds, which are preset by the system to determine the rate of change of the permeability coefficient.

[0029] Furthermore, in step four, the process of adjusting the grouting pressure is as follows:

[0030] Recommended values ​​for calculating grouting pressure The formula is as follows:

[0031]

[0032] in, This is the reference pressure for grouting;

[0033] α Empirical moderating factor;

[0034] The controller updates and controls the grouting pump pressure to the recommended value in real time. .

[0035] Furthermore, in step four, the process of adjusting the water-cement ratio is as follows:

[0036] Recommended combination of water-cement ratio The formula is as follows:

[0037]

[0038] in, Indicates the first The center value of the applicable permeability range corresponding to the water-cement ratio slurry;

[0039] The controller sequentially performs flushing and changes the water-cement ratio of the slurry to the recommended combination. Resume grouting operation.

[0040] Furthermore, in step four, the process of adjusting the cement particle size is as follows:

[0041] Recommended values ​​for selecting cement particle size The formula is as follows:

[0042]

[0043] in, Indicates the first Each particle size grade corresponds to a suitable center value of the permeability range;

[0044] The controller sequentially performs flushing and replaces the cement particle size of the slurry with the recommended value. Resume grouting operation.

[0045] Compared with the prior art, the beneficial effects of the present invention are:

[0046] This invention utilizes a high-precision pressure sensor to continuously monitor changes in the formation permeability coefficient during grouting construction and transmits the data to the controller in real time. This effectively avoids common problems in traditional grouting processes, such as over- or under-grouting, blind construction, ineffective grouting, and grout waste. It provides data support for dynamic grouting and ensures precise control during the grouting process. Simultaneously, the controller automatically adjusts grouting parameters (water-cement ratio, injection pressure, cement particle size) based on changes in the permeability coefficient. The real-time feedback mechanism ensures that grouting operations maintain optimal operating conditions under various formation conditions, flexibly responding to the needs of formations with different permeability, achieving the best grouting effect, reducing human error, and avoiding phenomena such as grout blockage at the grouting port, incomplete formation reinforcement, and poor reinforcement effect caused by failure to adjust to changes in formation conditions in a timely manner. This significantly improves construction quality and efficiency.

[0047] The grouting process combines real-time monitoring with dynamic adjustment, forming a perfect closed-loop intelligent control system: monitoring → analysis → judgment → adjustment → re-monitoring. Real-time monitoring of formation permeability and dynamic adjustment of grouting parameters during grouting are core manifestations of the refined, information-based, and intelligent development of modern geotechnical engineering. It is no longer about blindly filling a black box, but about achieving precise, safe, and efficient formation modification through "dialogue" with the formation. Detailed Implementation

[0048] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0049] In engineering grouting, the grouting parameters affecting the injectability of the grout include grouting pressure, water-cement ratio, cement particle size, and permeability coefficient. To verify the adaptability of grout injection under different stratum permeability conditions, orthogonal experiments were conducted, primarily examining the relationship between grouting pressure, water-cement ratio, cement particle size, and permeability coefficient. The orthogonal experiment using the controlled variable method determined the impact of a single factor on the grouting effect, allowing for the selection of the grout with optimal grouting parameters for engineering grouting. The experiments obtained the relationship between the permeability coefficient and grouting parameters for different strata, and the grouting method was scientifically optimized for strata with different permeability, ensuring optimal matching between the grouting process, grouting parameters, and stratum conditions, achieving high efficiency and safety in the grouting process.

[0050] The effects of four factors on injectability were selected: cement particle size, water-cement ratio, grouting pressure, and permeability coefficient. A controlled variable experimental scheme with four factors and three levels was designed to record the grout diffusion distance and time for each experimental group (the type of cement, water-cement ratio, and grouting pressure can be determined according to the actual site conditions).

[0051]

[0052] Test materials: high permeability formation samples, medium permeability formation samples, low permeability formation samples, fine-grained cement, medium-grained cement, coarse-grained cement, and water.

[0053] The experimental steps are as follows:

[0054] 1. Install the grouting pipe, constant pressure grouting module, earth pressure sensor, data acquisition unit (controller) and video recording equipment in sequence. Pressurize each functional module to the working pressure and check the airtightness of each interface and pipeline. Only after confirming that there is no leakage can you continue to the next step.

[0055] 2. Fill the grouting pipe with pre-prepared stratum samples of various permeability coefficients in layers of 15cm thickness. Each layer is compacted by light vibration or tapping. Place earth pressure cells at different depths from the pipe opening and connect them to the data acquisition device. Then, initialize all pressure channels to zero to ensure accurate readings.

[0056] 3. Prepare cement according to the designed water-cement ratio. Place each batch into the mixer, premix at a low speed for about 120 seconds, then switch to a high speed for about 120 seconds to fully mix until uniform and free of particles.

[0057] IV. Pressure Stabilization Grouting: Start the air compressor, adjust the pressure stabilizing valve to the target grouting pressure to keep the system pressure constant, open the outlet valve of the grout storage tank, and inject the grout into the grouting pipe. During the grouting process, keep the video recording and data acquisition running synchronously to record the grouting time, pressure changes, and the position of the grout front in real time.

[0058] 5. End grouting and export data. When the grout reaches the observation mark (or fills the test tube), immediately close the outlet valve to stop grouting, export all raw data such as pressure-time and displacement, and back up the video recording.

[0059] Experimental results show that in medium-to-high permeability formations (permeability coefficient greater than 0.3 cm / s), using fine-grained cement, only requiring an appropriate increase in the water-cement ratio and grouting pressure is sufficient to ensure smooth grout injection. When permeability further increases (permeability coefficient greater than 0.4 cm / s), even using coarser-grained cement, stable injection can be achieved under conventional grouting pressure (≥0.1 MPa) and conventional water-cement ratio (≥1.0). Different particle sizes of grout exhibit varying sensitivities to permeability coefficients: fine-grained cement requires slightly higher permeability conditions for successful injection; while medium-grained cement, with appropriate water-cement ratio and pressure control, also demonstrates good injection performance in medium-to-high permeability formations.

[0060] The above experimental results confirm that the particle size, water-cement ratio, and grouting pressure of the grout should be combined and matched according to the actual permeability of the formation to optimize grouting efficiency and uniformity. This conclusion provides an important basis for subsequent dynamic control of grouting parameters and grout selection strategies. Based on the above experimental results, this invention provides an intelligent grouting method based on real-time permeability monitoring, providing a reasonable basis for adjusting grouting parameters on the construction site. Technicians can select appropriate cement type, water-cement ratio, and injection pressure according to the real-time permeability coefficient to achieve site-specific grouting construction and ensure optimized reinforcement effect.

[0061] This embodiment provides an intelligent grouting method based on real-time permeability monitoring. This method uses pressure sensors to acquire the grout diffusion front time, inverts the formation permeability coefficient in real time, and triggers multi-level response strategies based on the magnitude of changes in the permeability coefficient, such as adjusting grouting pressure, changing the water-cement ratio, and replacing cement particle size. This achieves adaptive grouting control for different formation conditions. The automated system reduces human error, improves the accuracy of the grouting process, and can flexibly adjust the grouting strategy according to changes in the formation, ensuring efficient construction under complex geological conditions, thereby improving the construction efficiency and safety of the project. Specifically, it includes the following steps:

[0062] Step 1: Install a pressure monitoring array using pressure sensors in the area to be grouted, and electrically connect the pressure sensors to the controller.

[0063] A pressure sensor is placed every 10 cm along the grouting path as a pressure monitoring point, forming a two-dimensional or three-dimensional pressure monitoring array grid within the grouting area. Each pressure sensor is electrically connected to the controller via a signal line. The acquisition frequency of the pressure sensors is no less than 1 Hz to ensure sufficient time resolution. Simultaneously with the start of grouting, the pressure monitoring array begins acquisition, recording the pressure-time change curves at each measurement point. Preferably, the pressure sensor is a soil pressure cell. Specifically, the controller includes a data processing unit and a control feedback module for automated control. The data processing unit compares and analyzes the real-time permeability coefficient data with a pre-established "stratum permeability-grouting parameter" relationship database to identify the current soil permeability status. When a change in permeability coefficient is detected and exceeds a threshold, the control feedback module automatically adjusts grouting parameters, such as grouting pressure, water-cement ratio, and grouting rate, to maintain the continuity and uniformity of grout diffusion. Meanwhile, the controller is also equipped with a graphical visualization interface, which allows operators to view the pressure curves, permeability coefficient distribution maps, and current grouting parameters at each monitoring point in real time. When permeability changes abnormally or parameters exceed limits, the system will issue an alarm signal and link the control feedback module to automatically correct the grouting plan, realizing closed-loop control of "monitoring-identification-feedback-adjustment" to ensure that the grouting operation is always in the optimal working condition.

[0064] Step 2: Begin grouting and collect the time it takes for the grout to reach each measuring point.

[0065] When the grout front spreads to the vicinity of a certain measuring point, the earth pressure cell at that point will detect a significant pressure surge or slope change, enabling the controller to acquire the time it takes for the grout front to reach that measuring point. This allows for the automatic identification of the grout's arrival time at each measuring point. The system is set to allow the grout to reach the [number]th [measurement point]. The time for each measurement point is .

[0066] Step 3: Calculate the rate of change of the formation permeability coefficient.

[0067] Calculate the first Equivalent permeability coefficient at each measurement point The formula is as follows:

[0068]

[0069] in, The static head of the slurry. The viscosity of the slurry. The density of the slurry, It is the acceleration due to gravity. For the slurry front to reach the first Time at each measurement point From the grouting port to the first The path length of each measurement point on the diffusion principal plane, and the coordinates of the grouting port are... , No. The coordinates of the measurement points are .

[0070] Further calculations are needed at this moment (when the slurry front reaches the first...) The overall regional average permeability coefficient at each measurement point (at any given time) The formula is as follows:

[0071]

[0072] in, This represents the total number of measurement points through which the slurry flows at that moment, i.e., the number of points through which the slurry flows at that moment. There are 10 measurement points.

[0073] Calculate the rate of change of the permeability coefficient The formula is as follows:

[0074]

[0075] in, This is the difference between the permeability coefficient at this moment and the permeability coefficient at the previous moment; The permeability coefficient at the previous moment;

[0076] The system refreshes every 30 seconds. and the permeability coefficient at the previous moment. Compare, calculate Then, the rate of change of the permeability coefficient can be calculated. .

[0077] Step 4: Dynamically adjust the grouting parameters according to the rate of change of the permeability coefficient. The grouting parameters include grouting pressure, water-cement ratio, and cement particle size.

[0078] Specifically, when The slight change indicates that the current formation permeability is basically stable, and the decrease in grout diffusion efficiency is only due to changes in local grouting channels. At this time, the grouting pressure of the grouting pump is adjusted by the controller to improve the grout diffusion capacity. The process is as follows:

[0079] Recommended values ​​for calculating grouting pressure The formula is as follows:

[0080]

[0081] in, This is the reference pressure for grouting; α It is an empirical adjustment factor, usually set according to the working conditions in stages or according to the slurry / formation type, and can be slowly adaptive;

[0082] The controller updates and adjusts the grouting pump pressure to the recommended value in real time. .

[0083] when The time change is moderate, indicating that the grout diffusion is limited and increasing the grouting pressure can no longer effectively promote the grout diffusion. The controller executes the grout replacement logic one, that is, switches the grout to a water-cement ratio combination that is more suitable for the current formation. The process is as follows:

[0084] Recommended combination of water-cement ratio The formula is as follows:

[0085]

[0086] in, This indicates selecting the index that minimizes the absolute difference within the parentheses. ;

[0087] Indicates the first The center value of the applicable permeability range corresponding to the water-cement ratio slurry.

[0088] The controller finds the best match for the current permeability coefficient among all candidate water-cement ratio combinations. The water-cement ratio combination, i.e., reducing the water-cement ratio, involves sequentially performing flushing and changing the water-cement ratio of the slurry to the recommended combination. Resume grouting operation and simultaneously calibrate pressure and flow control strategies to prevent pipe blockage or grout leakage.

[0089] when The drastic change indicates a significant alteration in the formation's permeability structure (such as switching to a low-permeability layer, interlayer, or weathering zone). Adjusting the water-cement ratio and grouting pressure cannot meet the grout diffusion requirements. At this point, the controller executes grout replacement logic two, which involves changing the cement particle size grade to adapt to the new medium (i.e., the new formation permeability structure).

[0090] Recommended values ​​for selecting cement particle size The formula is as follows:

[0091]

[0092] in, This indicates selecting the index that minimizes the absolute difference within the parentheses. ;

[0093] Indicates the first Each particle size grade corresponds to a suitable center value of the permeability range.

[0094] The controller finds the best match for the current permeability among all candidate particle size classes. The particle size grade is adjusted by reducing the cement particle size, followed by flushing and replacing the cement particle size of the slurry with the recommended value. Resume grouting operation and simultaneously calibrate pressure and flow control strategies to prevent pipe blockage or grout leakage.

[0095] in, and These represent the first and second thresholds for the rate of change of the permeability coefficient, pre-set by the system, and the different formation conditions in the grouting area. and The range of values ​​will be different.

[0096] More specifically, homogeneous fine / medium sand (river sand, coral sand, etc.): ≈5% to 10%, ≈15% to 25%; gravelly sand, with obvious interlayers or strong heterogeneity: ≈10% to 15%; ≈25% to 40%; fractured / weathered rock and rapidly fluctuating scenarios: ≈12% to 18%; ≈30% to 45%.

[0097] Furthermore, in the early stages of grouting construction, multiple storage tanks are prepared in advance to store cement grout with different water-cement ratios and particle size distributions to meet the grouting needs of different permeability strata. The controller calculates the rate of change of the permeability coefficient based on real-time monitoring data, and then automatically selects the tank containing the appropriate water-cement ratio and particle size distribution from among the multiple tanks. The grout in that tank is then injected, and the injection pressure is adaptively adjusted to achieve real-time matching between the grout type and grouting parameters, ensuring that the specific needs of different strata can be met during the grouting construction process.

[0098] Furthermore, fiber Bragg grating sensors possess high sensitivity, resistance to electromagnetic interference, and distributed deployment capabilities. They can be deployed at different depths and orientations to achieve continuous monitoring of the formation state within the grouting influence range. During grouting construction, fiber Bragg grating sensors can be additionally deployed along the grouting path or at key locations in the surrounding rock as strain monitoring nodes. The fiber Bragg grating sensors are electrically connected to the controller to monitor formation micro-deformation, strain evolution, and grouting disturbance response in real time, providing high-precision formation safety data and thus accurately assessing the safety level during the grouting process. Specifically, referring to the monitoring index system in the current "SL 265-2016 Technical Specification for Safety Monitoring of Hydraulic Structures" and "GB 50330-2013 Technical Specification for Building Slope Engineering", and combined with the on-site working conditions and empirical parameters, the dynamic safety thresholds during grouting are set as follows: the strain rate per unit time does not exceed 100 με / h, the cumulative strain does not exceed 800 με, the displacement increment in the grouting area does not exceed 2 mm / 3 min, the strain gradient is controlled within 50 με / m, and the radius of the grouting disturbance range does not exceed 3 m (determined based on similar stratum test results or engineering experience). When the controller detects that the actual value is close to or exceeds the preset safety range, it will automatically trigger an alarm and suspend the grouting operation. Simultaneously, it will initiate data backtracking and anomaly identification processes, combining the strain spatial distribution to determine potential risks such as uneven diffusion at the grout front or excessive local structural response. It will also adjust grouting parameters (including grouting pressure, water-cement ratio, and grouting rate) in real time to restore the stability of the grouting operation, effectively improving the intelligence level and safety assurance capabilities of the grouting operation. This demonstrates strong engineering adaptability and promotional value, further ensuring the optimal diffusion effect of the grout. More specifically, when the monitoring data received by the controller indicates an abnormally high or sudden increase in the formation strain change rate, it determines that there may be a risk of stress concentration, excessively rapid grouting, or local blockage. The controller will then reduce the grouting pressure or suspend the grouting operation to avoid dangers such as splitting, arching, or quicksand. When the monitoring data received by the controller indicates insufficient strain response or slow diffusion in the grouting area, the controller will increase the grouting pressure or optimize the grout parameters to improve grouting efficiency and coverage. The application of fiber Bragg grating sensors greatly ensures the stability, uniformity, and reinforcement effect of the grouting process, reduces human intervention, and significantly improves the real-time safety control capability of the grouting process, providing effective protection for refined grouting construction under complex geological conditions.

[0099] Although the present invention has been described using the above preferred embodiments, it is not intended to limit the scope of protection of the present invention. Any changes and modifications made by those skilled in the art to the above embodiments without departing from the spirit and scope of the present invention shall still fall within the scope of protection of the present invention.

Claims

1. A smart grouting method based on real-time permeability monitoring, characterized in that, include: Step 1: Deploy a pressure monitoring array using pressure sensors in the area to be grouted. The pressure sensors are electrically connected to the controller. Step 2: Begin grouting and obtain the time it takes for the grout to reach each measuring point; Step 3: Calculate the rate of change of the formation permeability coefficient; Step 4: Dynamically adjust the grouting parameters based on the rate of change of the permeability coefficient. The grouting parameters include grouting pressure, water-cement ratio, and cement particle size. In step three, the specific process for calculating the rate of change of the formation permeability coefficient is as follows: Calculate the first Equivalent permeability coefficient at each measurement point The formula is as follows: ； in, The static head of the slurry. The viscosity of the slurry. The density of the slurry, It is the acceleration due to gravity. For the slurry front to reach the first Time at each measurement point From the grouting port to the first The path length of each measurement point on the diffusion principal plane, and the coordinates of the grouting port are... , No. The coordinates of the measurement points are: ; Calculate the overall regional average permeability coefficient for that time period. The formula is as follows: ； in, This represents the total number of measurement points through which the slurry flowed during that time period. Calculate the rate of change of the permeability coefficient The formula is as follows: ； in, This is the difference between the current permeability coefficient and the previous permeability coefficient. This represents the permeability coefficient at the previous time point.

2. The intelligent grouting method based on real-time permeability monitoring according to claim 1, characterized in that, In step one, the pressure monitoring array is formed by placing a pressure sensor every 10cm in the area to be grouted, and the pressure sensor is a soil pressure cell.

3. The intelligent grouting method based on real-time permeability monitoring according to claim 1, characterized in that, In step four, the method for dynamically adjusting the grouting parameters based on the rate of change of the permeability coefficient is as follows: when Adjust the grouting pressure as needed; when Adjust the water-cement ratio as needed; when Adjust the cement particle size as needed; in, and These are the first and second thresholds, which are preset by the system to determine the rate of change of the permeability coefficient.

4. The intelligent grouting method based on real-time permeability monitoring according to claim 3, characterized in that, In step four, the process of adjusting the grouting pressure is as follows: Recommended values ​​for calculating grouting pressure The formula is as follows: ； in, This is the reference pressure for grouting; Empirical moderating factor; The controller updates and controls the grouting pump pressure to the recommended value in real time. .

5. The intelligent grouting method based on real-time permeability monitoring according to claim 3, characterized in that, In step four, the process of adjusting the water-cement ratio is as follows: Recommended combination of water-cement ratio The formula is as follows: ； in, Indicates the first The center value of the applicable permeability range corresponding to the water-cement ratio slurry; The controller sequentially performs flushing and changes the water-cement ratio of the slurry to the recommended combination. Resume grouting operation.

6. The intelligent grouting method based on real-time permeability monitoring according to claim 3, characterized in that, In step four, the process of adjusting the cement particle size is as follows: Recommended values ​​for selecting cement particle size The formula is as follows: ； in, Indicates the first Each particle size grade corresponds to a suitable center value of the permeability range; The controller sequentially performs flushing and replaces the cement particle size of the slurry with the recommended value. Resume grouting operation.

Images