Scouring pile foundation reinforcing method based on MICP curing principle

Abstract

The invention discloses a scouring pile foundation reinforcement method based on an MICP curing technology, which comprises the following steps: acquiring initial environment information such as scouring pit parameters, water flow parameters, tide period and seawater salinity of a delimited area around a pile, and determining grouting parameters such as a grouting window period and a safe flow velocity threshold value and a matching numerical value of a bacterial liquid concentration, a urea concentration and a calcium ion concentration; a grouting assembly composed of a first grouting pipe and a second grouting pipe which are spliced up and down is arranged, and grouting holes are formed in the side wall of the second grouting pipe which is pre-buried in a soil layer; after MICP slurry is prepared according to blending parameters, the slurry is injected into a soil layer in combination with grouting parameters, and meanwhile, the grouting process is dynamically adjusted by monitoring the resistivity of a soil body in real time; and after grouting is completed, the assembly is dismantled, and supplementary grouting is conducted on the local area according to the detection result. According to the method, the accuracy and reliability of pile foundation reinforcement are achieved through environmental parameter adaptation, grout dynamic regulation and control and layered detection and reinjection.

Description

Technical Field

[0001] The present invention relates to the technical field of underwater pile foundation scour reinforcement, and particularly to a scour pile foundation reinforcement method based on the MICP curing principle. Background Art

[0002] In marine engineering projects, such as cross-sea bridges, offshore oil and gas platforms, and offshore wind turbines, pile foundations, as important load-bearing parts of the structure, their performance is directly related to the safety and service life of the entire project. The complexity of the marine environment poses many severe challenges to pile foundations. Under the long-term action of continuous scour by waves and ocean currents and complex geological conditions, the soil around the pile foundation may be lost, loosened, or have reduced strength, resulting in a decrease in the bearing capacity of the pile foundation and even the risk of overall structural failure. Especially in underwater pile foundations, the exposure of pile foundations caused by scour and the loss of surrounding soil are common problems in the engineering field and require effective reinforcement and repair methods.

[0003] Currently, common pile foundation reinforcement technologies include methods such as grouting reinforcement, steel pipe and reinforced concrete wrapping. Although these technologies have improved the stability of pile foundations to a certain extent, they each have obvious deficiencies. Traditional grouting reinforcement: The commonly used cement slurry has poor permeability, a long setting time, and insufficient durability, and it is difficult to meet the complex requirements of pile foundation reinforcement after scour. Reinforcement by wrapping steel pipes or reinforced concrete is complex in construction, high in cost, and even more difficult to implement in the underwater environment. These traditional methods cannot provide an ideal solution when dealing with complex scour and geological conditions in the marine environment. Therefore, there is an urgent need to develop a pile foundation reinforcement technology that is efficient, economical, environmentally friendly, and easy to implement. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to propose a scour pile foundation reinforcement method based on the MICP curing principle, which uses the mineralization reaction of microorganisms to reinforce the pile foundation after scour and solve the problems of low efficiency and high cost of existing pile foundation reinforcement technologies.

[0005] To achieve the above technical purpose, the technical solution adopted by the present application is: A scour pile foundation reinforcement method based on the MICP curing principle, including: Obtaining initial environmental information, where the initial environmental information includes scour pit parameters, water flow parameters, tidal cycle, and seawater salinity in the area demarcated around the pile; Formulating grouting parameters according to the initial environmental information, where the grouting parameters include the grouting window period and the safety flow velocity threshold, and formulating the MICP mixing parameters according to the initial environmental information, where the mixing parameters include the bacterial solution concentration, urea concentration, calcium ion concentration, and mixing ratio value; Arrange a grouting assembly, the grouting assembly includes a first grouting pipe and a second grouting pipe, the first grouting pipe and the second grouting pipe are sequentially assembled from top to bottom, a plurality of grouting holes are arranged on the side wall of the second grouting pipe, and the second grouting pipe is pre-buried in the soil layer of the designated area around the pile; Prepare MICP slurry according to the formulation parameters; Inject the MICP slurry into the soil layer through the grouting assembly according to the grouting parameters, obtain the soil resistivity feedback information of the designated area around the pile during the grouting process, and dynamically adjust the grouting parameters according to the soil resistivity feedback information; After the grouting is completed, the grouting components are removed; And, the area demarcated around the pile is detected, the detection result is generated, the supplementary grouting information is generated according to the detection result, and the supplementary grouting is performed on the local position in the area demarcated around the pile according to the supplementary grouting information.

[0006] In some embodiments, obtaining initial environment information includes: Use the multi-beam detection method to scan the area defined around the pile to obtain scanning size parameters, which include the scanning boundary and scanning elevation of the scour pit; Obtaining preset size parameters, and correcting the preset size parameters according to the scanned size parameters to obtain corrected size parameters; Input the modified size parameters into the three-dimensional modeling software to construct the scour pit model and calculate the fill mass required for the scour pit model; Generate scour pit parameters based on fill quality and modified size parameters; and, disposing at least one flow velocity sensor in a designated area around the pile, and collecting water flow parameters through the flow velocity sensor; And, obtaining geographical location information of the area demarcated around the pile, the geographical location information being longitude and latitude coordinates; Obtain the tidal cycle and seawater salinity of the area defined around the pile based on the geographic location information; Initial environmental information is generated based on scour pit parameters, water flow parameters, tidal cycle, and seawater salinity.

[0007] In some embodiments, inputting the modified size parameters into a three-dimensional modeling software to construct a scour pit model, and calculating the filling mass required for the scour pit model includes: Taking the center of the pile foundation as the origin, a three-dimensional coordinate system of the scour pit is constructed; The mathematical model of the scour pit is constructed according to the modified size parameters and is expressed by formula (1). Formula (1) is as follows: ; In formula (1), It is a preset elevation surface converted according to the preset size parameters. is the coordinate of the scour pit along the water flow direction, is the coordinate of the scouring pit along the vertical water flow direction, is the coordinate of the scouring pit along the vertical direction, is the measured elevation surface obtained by converting according to the scanning dimension parameters, is the elevation difference function, is the first conversion function for converting the preset dimension parameters into the preset elevation surface, is the second conversion function for converting the scanning dimension parameters into the measured elevation surface; The filling volume is calculated by the numerical integration method, which is expressed by formula (2), and formula (2) is as follows: ; In formula (2), is the filling volume, is the projection area of the scouring pit along the vertical direction, is the elevation difference of the center point of the th unit, is the area of the th unit, is a positive integer; ; In formula (3), is the filling mass, is the dry density of the filling material, is the construction loss coefficient.

[0008] In some embodiments, formulating the grouting parameters according to the initial environmental information includes: Obtaining the water flow parameters in the area demarcated around the pile during the preset period continuously collected by the flow velocity sensor; Establishing a flow velocity-time change curve and aligning its time sequence with the tidal period to obtain a flow velocity-tidal change curve; Obtaining a first characteristic flow velocity point corresponding to the high slack tide and a second characteristic flow velocity point corresponding to the low slack tide in the flow velocity-tidal change curve; Generating a periodic time period corresponding to the safe flow velocity threshold according to the first characteristic flow velocity point and the second characteristic flow velocity point; Generating a grouting window period according to the periodic time period.

[0009] In some embodiments, formulating the grouting parameters according to the initial environmental information further includes: Obtaining the experimental data of the diffusion distribution of the grouting liquid at different flow velocities and constructing a flow velocity-effective curing curve of the grouting liquid according to the diffusion distribution experimental data; Generate a critical flow rate corresponding to the range of the preset curing threshold according to the effective curing curve of the flow rate - grouting liquid; Obtain a preset correction coefficient, and correct the critical flow rate according to the preset correction coefficient to obtain a safety flow rate threshold.

[0010] In some embodiments, formulating the mixing parameters of MICP according to the initial environmental information includes: According to the seawater salinity, generate the first reaction concentration range of Bacillus pasteurii based on the preset salinity - bacterial solution concentration relationship; Generate the second reaction concentration range of urea according to the Michaelis - Menten equation; Obtain the water flow parameters to generate the third reaction concentration range of calcium ions; Generate a corrected ratio according to the first reaction concentration range, the second reaction concentration range, and the third reaction concentration range; Prepare the slurry of MICP according to the corrected ratio.

[0011] In some embodiments, generating the first reaction concentration range of Bacillus pasteurii based on the preset salinity - bacterial solution concentration relationship according to the seawater salinity includes: Obtain the reference bacterial solution concentration corresponding to the preset reference salinity; Calculate the salinity difference between the seawater salinity and the preset reference salinity; Generate a bacterial solution concentration adjustment amount according to the preset salinity - bacterial solution concentration relationship and the salinity difference; Superimpose the bacterial solution concentration adjustment amount on the reference bacterial solution concentration to generate the first reaction concentration range; Generating the second reaction concentration range of urea according to the Michaelis - Menten equation includes: Obtain the Michaelis constant Km value of Bacillus pasteurii; Calculate the reaction rate at different urea concentrations based on the Michaelis - Menten equation; Select the concentration interval corresponding to 90% of the maximum rate of the reaction rate as the second reaction concentration range; Obtaining the water flow parameters to generate the third reaction concentration range of calcium ions includes: Establish a corresponding relationship model between the flow rate and the calcium ion concentration; Output the calcium ion concentration interval matching the current flow rate in the corresponding relationship model according to the water flow parameters as the third reaction concentration range.

[0012] In some embodiments, generating a corrected ratio according to the first reaction concentration range, the second reaction concentration range, and the third reaction concentration range includes: Establish a multi - parameter optimization model, and input the first reaction concentration range, the second reaction concentration range, and the third reaction concentration range into the multi - parameter optimization model; The multi-parameter optimization model is solved using the sequential quadratic programming algorithm to obtain the corrected ratio.

[0013] In some embodiments, the MICP slurry is injected into the soil layer through the grouting assembly according to the grouting parameters, and at the same time, the soil resistivity feedback information of the designated area around the pile during the grouting process is obtained. Dynamically adjusting the grouting parameters according to the soil resistivity feedback information includes: Obtain the real-time water flow parameters of the designated area around the pile in real time; Adjust the output power of the delivery pump proportionally according to the change of the real-time water flow parameters: When the water flow velocity increases, the power of the delivery pump is correspondingly increased; When the flow rate decreases, the power of the delivery pump is adjusted according to the non-linear relationship; Adopt a staged grouting control procedure, including the first-stage grouting and the second-stage grouting. The first-stage grouting includes: Adopt the grouting pressure in the first pressure range and the grouting flow rate in the first flow rate range, and keep the urea within the first preset concentration range; Continuously monitor the decreasing rate of the soil resistivity; When the decreasing rate of the soil resistivity is lower than the first-stage threshold, transfer to the second-stage grouting. The second-stage grouting includes: Adopt the grouting pressure in the second pressure range and the grouting flow rate in the second flow rate range, and keep the urea within the second preset concentration range. The first pressure range is lower than the second pressure range, the first flow rate range is higher than the second flow rate range, and the first preset concentration range is lower than the second preset concentration range; Continuously monitor the decreasing rate of the soil resistivity; When the decreasing rate of the soil resistivity is lower than the second-stage threshold, extend the grouting time or add standby grouting points for grouting.

[0014] In some embodiments, the designated area around the pile is detected to generate a detection result. According to the detection result, supplementary grouting information is generated, and supplementary grouting is performed on local positions in the designated area around the pile according to the supplementary grouting information, including: Sampling and testing are carried out within the first preset time period after the grouting is completed. The testing items of the sampling and testing include calcium carbonate crystallinity and the initial strength of the soil; Divide the risk level according to the first detection result of the sampling and testing and generate an intermediate detection strategy. The intermediate detection strategy is configured to record the first detection index during the detection process. The first detection index is the compressive strength and the permeability coefficient index; When the first detection index does not meet the preset requirements, collect the position of the first weak area and formulate a supplementary grouting plan. The supplementary grouting plan includes the distribution information of the supplementary grouting points and the supplementary grouting parameters. The supplementary grouting parameters include the inducer concentration and the supplementary grouting pressure; Performing grouting at the weak area according to the grouting scheme, and performing verification testing within a second preset time period after the grouting is completed; According to the second test result of the verification test, the risk level is divided and a backup test strategy is generated, where the backup test strategy is configured to record the second test indicator during the test process; When the second detection index does not meet the preset requirements, the location of the second weak area is collected and a backup grouting plan is formulated; Re-grouting the second weak area according to the backup re-grouting plan, and re-verify and test after the re-grouting is completed; Repeat the aforementioned verification and testing steps until the second test index meets the preset requirements.

[0015] By adopting the above technical solution, the present invention has the following beneficial effects compared with the prior art: The above technical scheme provides a scour pile foundation reinforcement method based on MICP solidification technology, including obtaining the initial environmental information such as scour pit parameters, water flow parameters, tidal cycle and seawater salinity in the area demarcated around the pile, and determining the grouting parameters such as grouting window period, safe flow rate threshold and the ratio of bacterial liquid concentration, urea concentration and calcium ion concentration; laying out a grouting assembly consisting of a first grouting pipe and a second grouting pipe spliced ​​together, wherein the side wall of the second grouting pipe is provided with a grouting hole and pre-buried in the soil layer; after preparing the MICP slurry according to the mixing parameters, it is injected into the soil layer in combination with the grouting parameters, and the grouting process is dynamically adjusted by real-time monitoring of the soil resistivity; after the grouting is completed, the assembly is removed, and the local area is supplemented with grouting according to the test results. This method achieves the accuracy and reliability of pile foundation reinforcement through environmental parameter adaptation, dynamic regulation of slurry and layered detection and re-injection. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 is a schematic diagram of steps S101 to S106 of the reinforcement method described in the specific implementation method; Figure 2 is an elevation view of the overall equipment layout described in the specific implementation method; Figure 3 is a structural elevation view of the MICP grouting equipment described in the specific implementation method; Figure 4 is a top view of the effect after the reinforcement method described in the specific implementation method is implemented; Figure 5 It is a simplified flowchart of the implementation process of the reinforcement method described in the specific implementation method.

[0018] The reference numerals are as follows: 1. Grouting components; 11. The first grouting pipe; 111, sleeve; 12. Second grouting pipe; 121. Grouting hole; 122. Capping; 2. MICP raw material box; 21. Bacillus pasteurianus solution tank; 22. Inducer raw material box; 23. Delivery hose; 3. Delivery pump; 4. Flow rate sensor. DETAILED DESCRIPTION

[0019] The present invention will be further described in detail below in conjunction with the accompanying drawings and examples. It is particularly noted that the following examples are only used to illustrate the present invention, but are not intended to limit the scope of the present invention. Similarly, the following examples are only partial embodiments of the present invention rather than all embodiments, and all other embodiments obtained by those of ordinary skill in the art without creative work are within the scope of protection of the present invention.

[0020] See also Figures 1 to 4 This embodiment provides a scouring pile foundation reinforcement method based on the MICP curing principle, comprising: S101, obtaining initial environmental information, the initial environmental information including scour pit parameters, water flow parameters, tidal cycle, and seawater salinity in the area defined around the pile; S102, formulating grouting parameters according to the initial environmental information, the grouting parameters including the grouting window period and the safe flow rate threshold, and formulating MICP preparation parameters according to the initial environmental information, the preparation parameters including the bacterial solution concentration, urea concentration, calcium ion concentration and the ratio value; S103, arranging a grouting assembly, the grouting assembly comprising a first grouting pipe and a second grouting pipe, the first grouting pipe and the second grouting pipe are sequentially assembled from top to bottom, a plurality of grouting holes are arranged on the side wall of the second grouting pipe, and the second grouting pipe is pre-buried in the soil layer in the designated area around the pile; S104, preparing MICP slurry according to the preparation parameters; S105, injecting the MICP slurry into the soil layer through the grouting assembly according to the grouting parameters, obtaining soil resistivity feedback information of the designated area around the pile during the grouting process, and dynamically adjusting the grouting parameters according to the soil resistivity feedback information; S106. After the grouting is completed, remove the grouting assembly; In addition, detect the designated area around the pile, generate a detection result, generate supplementary grouting information based on the detection result, and perform supplementary grouting on local positions in the designated area around the pile according to the supplementary grouting information.

[0021] In this embodiment, a transport ship is used to transport the tools and materials required for construction to the area to be reinforced, and the construction ship is preferably an anchor boat for anchoring and fixing.

[0022] In step S101, before repairing the scour pit of the pile foundation, determine the specific scope of the scour pit (i.e., scour pit parameters) through topographic scanning, and obtain detailed data on the topography around the pile, the elevation difference of the underwater soil layer, and the required filling volume. Preferably, the water flow parameters in the designated area around the pile are obtained through the flow velocity sensor 4, and the tidal cycle is counted through the local tide table.

[0023] In step S102, formulate a grouting window period in combination with the water flow parameters and the tidal cycle, and determine the safe flow velocity threshold according to the water flow parameters and the curing efficiency of the grouting liquid.

[0024] According to the scanning and detection results of the designated area around the pile, as well as the monitoring data of the water flow parameters, prepare Bacillus pasteurii for MICP and its inducing agents such as urea and calcium chloride in combination with the seawater salinity, and optimize their concentrations and ratios to ensure an efficient mineralization reaction. The goal and process of optimizing the concentrations of different parameters can be achieved.

[0025] In step S103, according to the actual depth of the pile foundation from the rigid bedrock at the bottom of the water, penetrate the grouting assembly 1 into the water from top to bottom. According to the actual depth of the pile foundation from the bedrock at the bottom of the water, vertically install the grouting assembly 1 to a predetermined depth, ensure that the pipeline is straight, and avoid bending or twisting to reduce the grouting resistance.

[0026] The grouting assembly 1 is composed of a first grouting pipe 11 and a second grouting pipe 12 connected by a sleeve 111, and can be freely and flexibly spliced and extended or shortened according to the length required for actual construction. The first grouting pipe 11 needs to reach the actual depth of the area to be reinforced, and the second grouting pipe 12 needs to fully contact the underwater soil layer horizontally to ensure that the MICP microbial solution can be evenly sprayed into the soil; Further, the grouting equipment used in the above steps mainly includes the following MICP raw material tank 2, delivery pump 3, first grouting pipe 11 and second grouting pipe 12. The MICP raw material tank 2 includes a Bacillus pasteurii solution tank 21 and an inducer raw material tank 22. The Bacillus pasteurii solution tank 21 is used to store the bacterial solution containing active Bacillus pasteurii to ensure that the concentration of the bacterial solution is moderate and its activity is maintained; the inducer raw material tank 22 is preferably multiple, and multiple inducer raw material tanks 22 store inducers such as urea and calcium chloride respectively, and inject the corresponding inducer according to the optimized ratio according to actual needs; the delivery pump 3 is a pressurized delivery pump, and two sections of delivery hoses 23 can be used to connect to the MICP raw material tank 2. The delivery pump 3 has the function of freely adjusting the pressure to accurately control the flow rate and pressure of grouting. The other end of the delivery pump 3 is connected to the first grouting pipe 11 to ensure that the MICP microbial solution can be evenly and stably delivered to the area to be reinforced.

[0027] The first grouting pipe 11 is used to transport the MICP microbial solution to the second grouting pipe 12 connected to the end. During the transportation process, the bacteria and inducers in the MICP microbial solution can be fully mixed in the first grouting pipe 11 to promote the effective precipitation of calcium carbonate. According to the actual construction requirements, multiple sections of the first grouting pipe 11 can be connected through the sleeve 111 to meet the operation requirements at different depths; One end of the second grouting pipe 12 is connected to the first grouting pipe 11, and the other end is provided with a detachable sealing cap 122. When it is necessary to extend the second grouting pipe 12, the sealing cap 122 can be removed and multiple sections of grouting perforated pipes can be connected through the sleeve 111. The body of the second grouting pipe 12 is distributed with grouting holes 121 of the same size and evenly arranged to ensure that the MICP solution can be evenly sprayed into the soil to achieve the best reinforcement effect.

[0028] Specifically, according to the depth to be reached actually, the first grouting pipe 11 is first connected to the delivery pump 3. If the pipe length is not enough to reach the actual depth, two or more sections of the first grouting pipe 11 are sequentially connected and fixed by the sleeve 111. Finally, the second grouting pipe 12 is connected to the first grouting pipe 11 by the sleeve 111. The head of the second grouting pipe 12 is provided with a detachable sealing cap 122, which can meet the range requirements of different areas to be reinforced. The sealing cap 122 at the end of the second grouting pipe 12 connected to the outermost end cannot be removed during operation.

[0029] In step S105, before formal grouting, a water trial run is carried out to check the operation of the entire system, ensure that all equipment works normally, the pipeline is unobstructed, and the water is completely drained. Then, the MICP slurry is injected into the soil layer through the grouting assembly 1 according to the grouting parameters.

[0030] By installing an integrated depth detector and resistivity probes, the position of the end of the grouting pipe is monitored in real time with an accuracy of ±5 cm, so as to provide real-time feedback on the grouting depth. Among them, the depth detector can be an ultrasonic sensor or a pressure sensor. If the actual depth is less than the designed value, the grouting is paused, and the length of the first grouting pipe 11 is extended by connecting the sleeve 111; if the actual depth is greater than the designed value, the pipe is gradually withdrawn to avoid excessive penetration into the bedrock.

[0031] The soil response is measured by arranging multiple resistivity probes to measure the soil resistivity decline rate. Preferably, the distance between two adjacent resistivity probes is 10 cm. The soil resistivity decline rate reflects the penetration range of the bacterial solution. When the resistivity decline rate is insufficient, the grouting time can be extended or the grouting pressure can be increased, or additional grouting points can be added. Preferably, when the resistivity decline rate < 10%, it is considered that the resistivity decline rate is insufficient. The grouting time can be extended by 5 - 10 minutes every 10 minutes until it reaches the standard; the grouting pressure can be gradually increased from 0.3 MPa to 0.5 MPa, ensuring that the soil structure is not damaged; adding additional grouting points means adding a second grouting pipe 12 in the area with low resistivity.

[0032] In step S106, after confirming that the MICP microbial solution has been completely injected and initially reacted, the previously buried second grouting pipe 12 is gradually withdrawn in a predetermined order. The operation should be slow and steady to avoid unnecessary disturbance to the surrounding soil. Further, preset measures can be adopted to prevent unnecessary disturbance to the surrounding soil. Preferably, a lubricating coating and synchronous grouting compensation measures are used. The lubricating coating is to pre - coat a biodegradable lubricant (such as a polylactic acid film) on the outer wall of the second grouting pipe 12 to reduce the adhesion force with the soil; synchronous grouting compensation means controlling the pipe withdrawal speed within 0.5 m / min and performing synchronous grouting compensation.

[0033] After the MICP microbial solution is injected, it takes a certain time for calcium carbonate to fully precipitate and bond with the soil. During this period, the reaction progress can be monitored by regularly taking samples for testing. If the test indicators do not meet the standard, local supplementary grouting can be carried out. In the weak area of drilling and sampling, additional grouting points are added for supplementary injection. After supplementary injection for a period of time, samples are taken for testing again until the standard is met.

[0034] Of course, it is not limited to the above steps. For example, during the grouting process, according to the water flow rate and grouting speed, the first grouting pipe 11 can be slowly withdrawn from the MICP raw material tank 2 without having to wait until the grouting is completed. After the implementation of this embodiment, there is no need for a large amount of post - maintenance, which can save workload, reduce costs, and reduce the consumption of human and material resources, and has strong economic efficiency and practicality.

[0035] In this embodiment, by integrating environmental parameters, the grouting window period and slurry ratio are dynamically determined, significantly enhancing the environmental adaptability of the reinforcement plan; the split grouting assembly 1 is used to achieve layered and precise grouting. The grouting holes 121 evenly distributed on the second grouting pipe 12, combined with the adjustable delivery pump 3, ensure the uniform penetration of the MICP solution in the soil; based on the real-time monitoring and feedback mechanism of resistivity probes, by adjusting the grouting time, pressure and position, the slurry diffusion range can be controlled, avoiding resource waste; the connection structure between the depth detector and the sleeve 111 ensures the accurate positioning of the grouting pipe and prevents excessive penetration of the bedrock; after grouting, the pipe is withdrawn through the lubricating coating and synchronous grouting compensation technology, effectively reducing soil disturbance; regular sampling and detection combined with the local supplementary grouting strategy ensure sufficient calcium carbonate precipitation and a complete reinforcement layer. This method takes into account the construction flexibility and reinforcement reliability, greatly reducing the manpower maintenance requirements, and has the characteristics of high efficiency, environmental protection and economy.

[0036] In some embodiments, obtaining the initial environmental information includes: Using the multi-beam detection method to scan the area demarcated around the pile, obtaining the scan size parameters, where the scan size parameters include the scan boundary of the scour pit and the scan elevation; Obtaining the preset size parameters, and correcting the preset size parameters according to the scan size parameters to obtain the corrected size parameters; Inputting the corrected size parameters into 3D modeling software to construct a scour pit model, and calculating the filling mass required for the scour pit model; Generating scour pit parameters according to the filling mass and the corrected size parameters; And, setting at least one flow velocity sensor in the area demarcated around the pile, and collecting water flow parameters through the flow velocity sensor; And, obtaining the geographical location information of the area demarcated around the pile, where the geographical location information is the longitude and latitude coordinates; Obtaining the tidal cycle and seawater salinity of the area demarcated around the pile according to the geographical location information; Generating the initial environmental information according to the scour pit parameters, water flow parameters, tidal cycle and seawater salinity.

[0037] In this embodiment, the multi-beam detection method is a technology that uses a sonar array to perform high-resolution topographic scanning on the area around the pile. Through the acoustic wave reflection data, the planar boundary (scan boundary) and elevation data (scan elevation) of the scour pit are generated, thereby accurately quantifying the scour range.

[0038] The preset size parameters are the theoretical sizes of the scour pit preset based on engineering design requirements or historical data. By comparing with the actual scan size parameters, the corrected size parameters that are more suitable for the on-site working conditions are obtained.

[0039] Convert the corrected dimension parameters into a three-dimensional model using 3D modeling software, and determine the total amount of MICP slurry required in combination with the filling quality calculation to ensure that the filling volume matches the scour pit volume.

[0040] Preferably, by installing the ADV flow velocity sensor 4, the water flow velocity and flow rate in the water area where the pile foundation is located are monitored in real time. The flow velocity sensor 4 is arranged at fixed points in the defined area around the pile, continuously collecting data on the water flow velocity and direction, providing a dynamic basis for the grouting window period and the safe flow velocity threshold.

[0041] The tidal cycle and seawater salinity are based on the longitude and latitude coordinates where the pile foundation is located, retrieving the tidal pattern table and salinity distribution data in the marine environment database or real-time monitoring platform to ensure the adaptation of the MICP bacterial solution activity and the mineralization reaction.

[0042] In this embodiment, the scour pit parameters are accurately quantified through multi-beam detection and 3D modeling technology. Combining dynamic flow velocity monitoring and retrieval of the environmental database, the efficient integration of initial environmental information is achieved; based on the corrected dimension parameters and filling quality calculation, it is ensured that the amount of MICP slurry used precisely matches the reinforcement requirements; through preset parameter correction and multi-source data fusion, the environmental adaptability is enhanced, avoiding insufficient reinforcement or resource waste caused by data deviation. This method takes into account the objectivity of data acquisition and the scientific nature of model construction, laying a reliable foundation for subsequent grouting parameter optimization and construction plan formulation, and significantly improving the accuracy and engineering efficiency of pile foundation reinforcement.

[0043] In some embodiments, inputting the corrected dimension parameters into 3D modeling software to construct a scour pit model, and calculating the filling quality required for the scour pit model includes: Taking the pile foundation center as the origin, construct a three-dimensional coordinate system for the scour pit; Construct a mathematical model of the scour pit according to the corrected dimension parameters, which is represented by formula (1), and formula (1) is as follows: ; In formula (1), is the preset elevation surface converted from the preset dimension parameters, is the coordinate of the scour pit along the water flow direction, is the coordinate of the scour pit along the direction perpendicular to the water flow, is the coordinate of the scour pit along the vertical direction, is the measured elevation surface converted from the scanned dimension parameters, is the elevation difference function, is the first conversion function for converting the preset dimension parameters into the preset elevation surface, is the second conversion function for converting the scanned dimension parameters into the measured elevation surface; Use the numerical integration method to calculate the filling volume, which is represented by formula (2), and formula (2) is as follows: ; In formula (2), is the filling volume, is the projection area of the scouring pit along the vertical direction, is the elevation difference of the center point of the th unit, is the th unit area, is a positive integer; The filling volume is converted into the filling mass, which is expressed by formula (3). Formula (3) is as follows: ; In formula (3), is the filling mass, is the dry density of the filling material, is the construction loss coefficient.

[0044] In this embodiment, by constructing a three-dimensional coordinate system of the scouring pit with the pile foundation center as the origin and combining the elevation difference function established with the corrected dimension parameters , the difference between the preset elevation surface and the measured elevation surface is quantified into an accurate mathematical model to realize the digital restoration of the scouring pit morphology; the numerical integration method is used to accumulate and calculate the filling volume V for the unit area in the projection area D and the corresponding elevation difference , significantly improving the accuracy and efficiency of the filling volume calculation; further introducing the dry density ρ of the filling material and the construction loss coefficient α, the volume is converted into the filling mass M to ensure the dynamic adaptation of the material usage to the actual working conditions and avoid excess or deficiency caused by theoretical calculation deviation.

[0045] In this embodiment, through the collaborative application of three-dimensional modeling and mathematical formulas, the scanning data obtained by the multi-beam detection method is converted into quantifiable and verifiable engineering parameters, which not only ensures the rigor of the scouring pit filling scheme, but also reduces the human estimation error. At the same time, it provides a scientific basis for the subsequent MICP slurry preparation and grouting construction, taking into account the reliability of resource optimization and reinforcement effect.

[0046] In some embodiments, formulating grouting parameters according to the initial environmental information includes: Obtaining the water flow parameters in the area demarcated around the pile during the preset period continuously collected by the flow velocity sensor; Establishing a flow velocity-time change curve and aligning its time series with the tidal cycle to obtain a flow velocity-tidal change curve; Obtaining the first characteristic flow velocity point corresponding to the high slack tide and the second characteristic flow velocity point corresponding to the low slack tide in the flow velocity-tidal change curve; Generate a periodic time period corresponding to the safe flow velocity threshold based on the first characteristic flow velocity point and the second characteristic flow velocity point; Generate a grouting window period based on the periodic time period.

[0047] In this embodiment, the ADV flow velocity sensor 4 is used to continuously record the water flow velocity in the pile foundation area, and a curve of the flow velocity changing with time is drawn.

[0048] Combined with the local tide table, clarify the time points of high slack tide (the slowest water flow) and low slack tide (the fastest water flow), and statistically analyze the daily tide change rule, which is the tidal cycle (for example, the interval between high and low tides is about 6 hours).

[0049] In the tidal cycle, select the 1 hour before and after the high slack tide as the candidate grouting window period, when the flow velocity is the lowest. Combined with weather prediction, eliminate high-risk periods, and finally generate 2-3 grouting window periods per day, each grouting window period lasting 1-2 hours. It should be noted that a 20% safety margin needs to be reserved for the grouting window period. For example, if the planned grouting time is 60 minutes, the grouting window period needs to be at least 75 minutes.

[0050] In this embodiment, the flow velocity sensor 4 is used to continuously collect the water flow parameters in the designated area around the pile and establish a flow velocity-time change curve. By aligning the time sequence with the tidal cycle, a flow velocity-tide change curve is generated, accurately identifying the first characteristic flow velocity point corresponding to the high slack tide and the second characteristic flow velocity point corresponding to the low slack tide, providing a dynamic basis for the periodic time period division of the safe flow velocity threshold; based on the regular fluctuation of the water flow velocity within the tidal cycle, the low flow velocity period is determined as the candidate grouting window period by screening the characteristic flow velocity points, and high-risk periods are eliminated by combining weather prediction data, further optimizing the reliability and safety of the grouting window period; by reserving a 20% safety margin, it is ensured that the actual grouting operation is completed within the planned duration, avoiding construction interruption caused by sudden changes in flow velocity or environmental interference; finally, 2-3 grouting window periods are generated per day, each grouting window period lasting 1-2 hours, taking into account construction efficiency and risk control, effectively reducing the negative impact of the high flow velocity environment on the diffusion of grouting slurry, and ensuring the stable implementation of the MICP reinforcement process. In this embodiment, through multi-source data fusion and dynamic threshold matching, the scientificity and environmental adaptability of grouting parameter formulation are significantly improved, providing refined construction guidance for pile foundation reinforcement in complex tidal waters.

[0051] In some embodiments, formulating grouting parameters according to the initial environmental information further includes: Obtain the diffusion distribution test data of the grouting liquid at different flow velocities, and construct a flow velocity-effective curing curve of the grouting liquid according to the diffusion distribution test data; Generate a critical flow velocity corresponding to the range of the preset curing threshold according to the flow velocity-effective curing curve of the grouting liquid; Obtain a preset correction coefficient, and correct the critical flow velocity according to the preset correction coefficient to obtain a safety flow velocity threshold.

[0052] In this embodiment, the relationship between the flow velocity and the grouting liquid diffusion efficiency is fitted according to the experimental data (for example, when the flow velocity ≤ 1.5 m / s, the solution diffusion uniformity > 90%), and an effective curing curve of the flow velocity - grouting liquid is constructed to further determine the safety flow velocity threshold. Preferably, the safety flow velocity threshold is set to 1.2 m / s. Exceeding this flow velocity may disperse the bacterial solution.

[0053] In this embodiment, an effective curing curve of the flow velocity - grouting liquid is constructed through the diffusion distribution test data to clarify the quantitative relationship between the slurry diffusion uniformity and the curing efficiency at different flow velocities, providing experimental support for the determination of the critical flow velocity; screening the critical flow velocity based on the preset curing threshold, and further correcting it through the preset correction coefficient to generate a safety flow velocity threshold that takes into account both safety and construction error tolerance, avoiding the curing failure caused by the dispersion of the bacterial solution in a high flow velocity environment; this embodiment dynamically correlates the experimental data with the engineering parameters to ensure that the selection of the grouting window period is strictly matched with the slurry performance, not only ensuring the uniformity and reliability of the MICP reinforcement, but also reducing the material waste caused by sudden changes in the flow velocity, and improving the process controllability of pile foundation repair in the tidal sea area.

[0054] In some embodiments, the formulation parameters of MICP are determined according to the initial environmental information, including: According to the seawater salinity, generate the first reaction concentration range of Bacillus pasteurii based on the preset salinity - bacterial solution concentration relationship; Generate the second reaction concentration range of urea according to the Michaelis - Menten equation; Obtain the water flow parameters to generate the third reaction concentration range of calcium ions; Generate a corrected ratio according to the first reaction concentration range, the second reaction concentration range, and the third reaction concentration range; Prepare the slurry of MICP according to the corrected ratio.

[0055] In this embodiment, the first reaction concentration range of Bacillus pasteurii is dynamically generated through the preset salinity - bacterial solution concentration relationship to ensure the stability of the bacterial activity under the change of seawater salinity; the second reaction concentration range of urea is deduced based on the Michaelis - Menten equation to accurately match the enzymatic reaction rate and improve the urea decomposition efficiency; the third reaction concentration range of calcium ions is adjusted in combination with the water flow parameters to balance the risk of calcium source dissolution and loss; a corrected ratio is generated by integrating the three to achieve the dynamic adaptation of the component concentration of the MICP slurry to the seawater salinity and the water flow conditions, not only ensuring the calcium carbonate precipitation rate and the uniformity of pile - perimeter reinforcement, but also avoiding the inactivation of the bacterial solution, excessive reactants, or the erosion loss of calcium ions, significantly improving the environmental adaptability and material utilization rate of the MICP process in the tidal environment.

[0056] In some embodiments, the first reaction concentration range of Bacillus pasteurii generated based on the preset salinity-bacterial liquid concentration relationship according to the seawater salinity includes: Obtain the reference bacterial liquid concentration corresponding to the preset reference salinity; Calculate the salinity difference between the seawater salinity and the preset reference salinity; Generate a bacterial liquid concentration adjustment amount according to the preset salinity-bacterial liquid concentration relationship and the salinity difference; Add the bacterial liquid concentration adjustment amount to the reference bacterial liquid concentration to generate the first reaction concentration range; The second reaction concentration range of urea generated according to the Michaelis-Menten equation includes: Obtain the Michaelis constant Km value of Bacillus pasteurii; Calculate the reaction rates at different urea concentrations based on the Michaelis-Menten equation; Select the concentration interval corresponding to the reaction rate reaching 90% of the maximum rate as the second reaction concentration range; Obtain the water flow parameters to generate the third reaction concentration range of calcium ions, including: Establish a corresponding relationship model between the flow velocity and the calcium ion concentration; Output the calcium ion concentration interval matching the current flow velocity in the corresponding relationship model according to the water flow parameters as the third reaction concentration range.

[0057] In this embodiment, the bacterial liquid concentration adjustment amount ensures the activity of bacteria. For example, when the salinity increases by 1‰, the bacterial liquid concentration needs to be increased by 20%.

[0058] The second reaction concentration range of urea generated according to the Michaelis-Menten equation is expressed by the following formula: ; Among them, represents the reaction rate, represents the maximum catalytic rate of the enzyme, represents the concentration of the substrate, represents the Michaelis constant. When the second reaction concentration range of urea = (Bacillus pasteurii ≈0.3 mol / L), the reaction rate reaches 90% of the maximum value, so the initial concentration is set to 0.5 - 0.6 mol / L.

[0059] To avoid premature precipitation and blockage of the pipeline, when the water flow velocity > 2 m / s, the calcium ion concentration needs to be reduced to 0.8 mol / L to reduce the flocculation rate; when the flow velocity < 1 m / s, the calcium ion concentration can be increased to 1.5 mol / L.

[0060] In this embodiment, by calculating the difference between the seawater salinity and the preset reference salinity, and combining the salinity-bacterial liquid concentration relationship, the first reaction concentration range of Bacillus pasteurii is dynamically adjusted to ensure the bacterial activity in a high-salinity environment; based on the Michaelis-Menten equation, the quantitative relationship between the urea concentration and the reaction rate is deduced, and the urea concentration range at which the reaction rate reaches 90% of the maximum rate is selected to ensure the efficient progress of the enzymatic reaction; a corresponding relationship model between the flow rate and the calcium ion concentration is established to balance the calcium source flocculation rate and the influence of water flow scouring, and to avoid pipeline blockage or calcium ion loss. Through the dynamic adaptation of multi-dimensional parameters, the scientific optimization of the MICP slurry ratio is realized, taking into account the bacterial activity, reaction efficiency and environmental adaptability, and improving the uniformity and durability of pile foundation reinforcement in tidal waters.

[0061] In some embodiments, generating a corrected ratio according to the first reaction concentration range, the second reaction concentration range, and the third reaction concentration range includes: Establish a multi-parameter optimization model, and input the first reaction concentration range, the second reaction concentration range, and the third reaction concentration range into the multi-parameter optimization model; Use the sequential quadratic programming algorithm to solve the multi-parameter optimization model to obtain the corrected ratio.

[0062] In this embodiment, the multi-parameter optimization model refers to a mathematical model that integrates the first reaction concentration range of Bacillus pasteurii, the second reaction concentration range of urea, and the third reaction concentration range of calcium ions. With the bacterial liquid activity, urea reaction efficiency, and calcium ion anti-scouring as the optimization objectives, the boundaries of each parameter are defined through constraint conditions.

[0063] The sequential quadratic programming algorithm iteratively solves the quadratic approximation sub-problems of the objective function and the constraint conditions, gradually approaches the optimal solution, and finally outputs the corrected ratio. The parameter range is determined by the preset salinity-bacterial liquid concentration relationship, the Michaelis-Menten equation, and the flow rate-calcium ion concentration model. After inputting into the model, the algorithm dynamically adjusts the ratio weights based on the gradient information to ensure that the bacterial liquid concentration adapts to the salinity change, the urea concentration matches the enzymatic reaction requirements, and the calcium ion concentration adapts to the water flow scouring conditions.

[0064] In this embodiment, through the synergistic effect of the multi-parameter optimization model and the sequential quadratic programming algorithm, the bacterial liquid activity, reaction efficiency, and anti-scouring performance are dynamically balanced, and the precise regulation of the MICP slurry ratio is realized. This method can avoid the activity inhibition or material waste caused by the isolated adjustment of a single parameter, ensure the stable metabolism of bacteria under salinity fluctuations, the controllable urea decomposition rate, and the balanced risk of calcium ion precipitation and loss, significantly improve the reliability and process adaptability of pile foundation reinforcement in the tidal environment, and at the same time reduce the probability of pipeline blockage.

[0065] In some embodiments, the MICP slurry is injected into the soil layer through a grouting assembly according to grouting parameters, and at the same time, the soil resistivity feedback information of the demarcated area around the pile during grouting is obtained. Dynamically adjusting the grouting parameters according to the soil resistivity feedback information includes: Obtain the real-time water flow parameters of the demarcated area around the pile in real time; According to the change of the real-time water flow parameters, adjust the output power of the delivery pump proportionally: When the water flow velocity increases, correspondingly increase the power of the delivery pump; When the flow rate decreases, adjust the power of the delivery pump according to a non-linear relationship; Adopt a staged grouting control procedure, including first-stage grouting and second-stage grouting. The first-stage grouting includes: Adopt a grouting pressure within the first pressure range and a grouting flow rate within the first flow rate range, and keep the urea within the first preset concentration range; Continuously monitor the decreasing rate of the soil resistivity; When the decreasing rate of the soil resistivity is lower than the first-stage threshold, transfer to the second-stage grouting. The second-stage grouting includes: Adopt a grouting pressure within the second pressure range and a grouting flow rate within the second flow rate range, and keep the urea within the second preset concentration range. The first pressure range is lower than the second pressure range, the first flow rate range is higher than the second flow rate range, and the first preset concentration range is lower than the second preset concentration range; Continuously monitor the decreasing rate of the soil resistivity; When the decreasing rate of the soil resistivity is lower than the second-stage threshold, extend the grouting time or add standby grouting points for grouting.

[0066] In this embodiment, the delivery pump 3 is started, and the power of the delivery pump 3 is adjusted correspondingly according to the water flow parameters (including the regional water flow velocity and flow rate) measured by the flow velocity sensor 4. The MICP microbial solution is sucked from the MICP raw material tank 2 into the delivery pump 3, fully mixed in the first grouting pipe 11 and pumped to the second grouting pipe 12, and sprayed from the grouting hole 121 to make full contact with the soil scouring around the pile foundation. The grouting pressure is 0.1~0.3 MPa, the flow rate is 5~10 L / min, and the injection time is 30~60 minutes. The penetration range of the bacterial solution is judged by the resistivity decrease rate (≥10%). If it does not meet the standard, the grouting time needs to be extended or the grouting points need to be increased.

[0067] By controlling the addition of the inducer, the grouting concentration in the first stage is 0.5 mol / L, the flow rate is 10 - 15 L / min, and it lasts for 15 - 20 minutes to promote bacterial attachment. In the second stage, the grouting concentration is increased to 1.5 mol / L, the flow rate is 5 - 8 L / min, and it is maintained for 30 - 40 minutes to trigger calcium ion flocculation, ensuring that calcium carbonate precipitation occurs within an appropriate time and enhancing the strength and stability of the soil mass. After each grouting cycle, the unconfined compressive strength of the soil mass is detected (≥0.5 MPa). If the standard is not met, the grouting is repeated and the inducer concentration is increased (to 2.0 mol / L) to strengthen deep solidification.

[0068] By obtaining in real time the feedback information of the soil resistivity in the demarcated area around the pile, and combining with the dynamic changes of the water flow parameters during the grouting process, the output power of the delivery pump 3 is adjusted in proportion or in a non-linear relationship to ensure the effective penetration and uniform diffusion of the MICP slurry under different flow velocity conditions; a staged grouting control procedure is adopted. In the first stage of grouting, a lower pressure, a higher flow rate and a lower urea concentration are used to promote the rapid attachment and initial metabolism of the bacterial solution, and the penetration range of the bacterial solution is accurately judged through the resistivity decrease rate threshold. When the rate is insufficient, the grouting is switched to the second stage, and a higher pressure, a lower flow rate and a higher urea concentration are used to trigger efficient calcium ion flocculation, improving the density and uniformity of calcium carbonate precipitation; based on the resistivity monitoring results, the grouting time is dynamically extended or standby grouting points are added to solve the problem of insufficient local penetration, avoid uneven soil solidification strength, and at the same time strengthen the consolidation of deep soil through the regulation of the inducer concentration gradient, significantly improving the reliability and process adaptability of pile foundation reinforcement in a scouring environment, and reducing the risks of slurry waste and pipeline blockage.

[0069] In some embodiments, the demarcated area around the pile is detected to generate a detection result, and supplementary grouting information is generated according to the detection result. Supplementary grouting of local positions in the demarcated area around the pile according to the supplementary grouting information includes: Sampling and detection are carried out within the first preset time period after the grouting is completed. The detection items for sampling and detection include calcium carbonate crystallinity and the preliminary strength of the soil mass; The risk level is divided according to the first detection result of the sampling and detection, and a mid-term detection strategy is generated. The mid-term detection strategy is configured to record the first detection index during the detection process. The first detection index is the compressive strength and the permeability coefficient index; When the first detection index does not meet the preset requirements, the position of the first weak area is collected and a supplementary grouting plan is formulated. The supplementary grouting plan includes the distribution information of the supplementary grouting points and the supplementary grouting parameters. The supplementary grouting parameters include the inducer concentration and the supplementary grouting pressure; Supplementary grouting is carried out on the position of the weak area according to the supplementary grouting plan, and verification detection is carried out within the second preset time period after the supplementary grouting is completed; Divide the risk level according to the second test result of the verification test and generate a backup test strategy, which is configured to record the second test index during the test process; When the second test index does not meet the preset requirements, collect the position of the second weak area and formulate a backup grouting plan; Perform supplementary grouting on the position of the second weak area according to the backup grouting plan, and, after the supplementary grouting is completed, perform verification testing again; Repeat the above verification testing steps until the second test index meets the preset requirements.

[0070] In this embodiment, after the MICP microbial solution is injected, it takes a certain time for calcium carbonate to fully precipitate and combine with the soil. Depending on the specific engineering situation, it usually takes several days to several weeks. During this period, the reaction progress can be monitored by regular sampling and testing. If the test index does not meet the standard, such as the unconfined compressive strength is less than 1.0 Mpa or the permeability coefficient is greater than 10⁻ 5 cm / s, local supplementary grouting can be carried out. At the weak area of the borehole sampling, additional grouting points are added. Preferably, a 2.0 mol / L inducer is used, the grouting pressure is increased to 0.4 MPa, the flow rate is 8 L / min, and it lasts for 40 minutes. Resampling and testing are carried out 3 days after the supplementary grouting until the standard is met.

[0071] The detection period can be dynamically adjusted according to the risk level of the initial detection results to ensure uniform and stable calcium carbonate precipitation. The risk level division can refer to the following criteria: Low risk: unconfined compressive strength ≥ 1.2 MPa, XRD > 90%. After the core drilling test for 28 days, it can be changed to quarterly detection; Medium risk: unconfined compressive strength 0.8 - 1.0 Mpa, detect once every 14 days for 3 months; High risk: unconfined compressive strength < 0.8 Mpa, detect and perform supplementary grouting weekly until the standard is met.

[0072] After waiting for the MICP microbial solution to react completely and fully contact with the soil to form a solidified material with high strength, high density, and high adhesiveness, perform strength tests on the soil and calcium carbonate solidified material in the reinforcement area. Take samples for X-ray diffraction (XRD) testing after 7 days to confirm that the calcium carbonate crystallinity > 85%. Take core samples after 28 days to test the unconfined compressive strength (≥ 1.0 MPa) and the permeability coefficient (≤ 10⁻ 5 cm / s) to ensure that the reinforcement effect meets the design requirements. Further, through long-term buried displacement gauges (accuracy ±0.1 mm) and resistivity sensors (calibrated once a year), the scour risk is warned in real time.

[0073] In this embodiment, the calcium carbonate crystallinity and the initial soil strength index are obtained through sampling and testing after grouting. Based on the first test results, the risk level is divided and a medium-term test strategy is generated. Combining the dynamic monitoring of the compressive strength and permeability coefficient indicators, the location of the first weak area is accurately positioned and a supplementary grouting plan including the inducer concentration and the supplementary grouting pressure is formulated to achieve targeted repair of local defects. After the supplementary grouting is completed, verification testing is carried out. According to the second test results, the risk level is divided and a standby test strategy is generated. The standby supplementary grouting plan is iteratively optimized for the location of the second weak area. Through the closed-loop control of multiple rounds of verification testing and supplementary grouting, it is ensured that the compressive strength and permeability coefficient of the soil are gradually increased to the preset requirements. Based on the dynamic adjustment of the risk level, the test cycle and supplementary grouting parameters are adjusted, taking into account the uniformity of calcium carbonate precipitation and the stability of the solidified product, avoiding reinforcement lag or local strength deficiency caused by a single test cycle, significantly improving the reliability and process adaptability of pile foundation reinforcement, and reducing material waste and secondary construction risks.

[0074] Please refer to Figure 5 , further, the following examples can be developed in combination with the above technical solutions: The above method steps can be understood as: Based on the water flow velocity and the range to be reinforced, the Bacillus pasteurii of MICP and its inducer are prepared, and their concentration and ratio are optimized; The MICP raw material grouting perforated pipe is buried in the range to be reinforced; Based on the water flow velocity, the power pressure of the delivery pump is adjusted, and the Bacillus pasteurii and the inducer are delivered for mixing and reaction; Strength testing is carried out to ensure that the strength of the reinforced range reaches the expectation.

[0075] Adopting the above technical solution, compared with the prior art, the beneficial effects of the present invention are: The present invention dynamically formulates the grouting window period and slurry preparation parameters by integrating environmental information such as scour pit parameters, water flow parameters, tidal cycle, and seawater salinity. Combining with the layered precise grouting design of the split grouting component, using the grouting holes evenly distributed on the second grouting pipe and the adjustable delivery pump to ensure the uniformity of MICP slurry penetration in the soil; based on the real-time feedback of resistivity probes and the dynamic adjustment of the delivery pump power, adopting a staged grouting strategy, matching the requirements of bacterial liquid adhesion and calcium ion flocculation through a combined mode of low pressure and high flow and high pressure and low flow to improve the density of calcium carbonate precipitation; ensuring the precise positioning of the grouting pipe through the connection structure of the depth detector and the sleeve, and combining the lubricating coating and synchronous grouting compensation technology to reduce the disturbance during pipe extraction; calculating the filling quality based on three-dimensional modeling and mathematical formulas, and dynamically optimizing the ratio of bacterial liquid, urea, and calcium ions by combining the multi-parameter optimization model and sequential quadratic programming algorithm to ensure the reaction efficiency under the changes of salinity and flow rate; after grouting, generating a mid-term detection strategy and supplementary grouting plan through risk level classification, iteratively executing verification detection and standby supplementary grouting to achieve targeted repair of local defects and gradual increase of compressive strength, significantly enhancing the uniformity, reliability, and process adaptability of pile foundation reinforcement in the tidal environment, and reducing material waste and secondary construction risks.

[0076] In addition, in each embodiment of the present invention, each functional unit may be integrated into one processing unit, or each unit may exist physically alone, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of a software functional unit.

[0077] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it may be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, may be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) or a processor to execute all or part of the steps of the methods in each embodiment of the present invention. The aforementioned storage medium includes various media that can store program codes, such as USB flash drives, mobile hard disks, read-only memories (ROM, Read-Only Memory), random access memories (RAM, Random Access Memory), magnetic disks, or optical discs.

[0078] The above are only some embodiments of the present invention, and thus do not limit the protection scope of the present invention. Any equivalent device or equivalent process transformation made by using the content of the specification and drawings of the present invention, or directly or indirectly applied in other related technical fields, shall similarly be included in the patent protection scope of the present invention.

Claims

1. A scour pile foundation reinforcement method based on the MICP curing principle, characterized in that, include: Acquiring initial environmental information, the initial environmental information including scour pit parameters, water flow parameters, tidal cycle, and seawater salinity in a designated area around the pile; Formulate grouting parameters according to the initial environmental information, wherein the grouting parameters include a grouting window period and a safe flow rate threshold, and formulate MICP preparation parameters according to the initial environmental information, wherein the preparation parameters include a bacterial solution concentration, a urea concentration, a calcium ion concentration, and a ratio value; Arrange a grouting assembly, wherein the grouting assembly includes a first grouting pipe and a second grouting pipe, wherein the first grouting pipe and the second grouting pipe are sequentially assembled from top to bottom, a plurality of grouting holes are arranged on the side wall of the second grouting pipe, and the second grouting pipe is pre-buried in the soil layer in the area defined around the pile; Prepare MICP slurry according to the formulation parameters; Injecting the MICP slurry into the soil layer through the grouting assembly according to the grouting parameters, obtaining soil resistivity feedback information of the area defined around the pile during the grouting process, and dynamically adjusting the grouting parameters according to the soil resistivity feedback information; After the grouting is completed, removing the grouting assembly; And, the area demarcated around the pile is detected to generate a detection result, supplementary grouting information is generated according to the detection result, and supplementary grouting is performed on a local position in the area demarcated around the pile according to the supplementary grouting information.

2. The scour pile foundation reinforcement method based on the MICP curing principle according to claim 1, wherein Obtaining initial environment information includes: Scanning the area defined around the pile using a multi-beam detection method to obtain scanning size parameters, wherein the scanning size parameters include a scanning boundary and a scanning elevation of the scour pit; Acquire preset size parameters, and modify the preset size parameters according to the scanned size parameters to obtain modified size parameters; Inputting the modified size parameters into a three-dimensional modeling software to construct a scour pit model, and calculating the filling mass required for the scour pit model; generating the scour pit parameters according to the filling quality and the modified size parameters; and, disposing at least one flow velocity sensor in a designated area around the pile, and collecting water flow parameters through the flow velocity sensor; And, obtaining geographical location information of the area demarcated around the pile, wherein the geographical location information is longitude and latitude coordinates; Acquire the tidal period and seawater salinity of the area defined around the pile according to the geographical location information; The initial environmental information is generated according to the scour pit parameters, water flow parameters, tidal cycle, and seawater salinity.

3. The scour pile foundation reinforcement method based on the MICP curing principle according to claim 2, characterized in that, Inputting the modified size parameters into the three-dimensional modeling software to construct a scour pit model, and calculating the filling mass required for the scour pit model includes: Taking the center of the pile foundation as the origin, a three-dimensional coordinate system of the scour pit is constructed; The mathematical model of the scour pit is constructed according to the modified size parameters and is expressed by formula (1). The formula (1) is as follows: ； In formula (1), is the preset elevation surface obtained by converting according to the preset dimension parameters, is the coordinate of the scour pit along the water flow direction, is the coordinate of the scour pit along the direction perpendicular to the water flow, is the coordinate of the scour pit along the vertical direction, is the measured elevation surface obtained by converting according to the scanned dimension parameters, is the elevation difference function, is the first conversion function for converting the preset dimension parameters into the preset elevation surface, is the second conversion function for converting the scanned dimension parameters into the measured elevation surface; The filling volume is calculated by numerical integration method and is expressed by formula (2), which is as follows: ； In formula (2), is the filling volume, is the projection area of the scouring pit along the vertical direction, is the elevation difference of the center point of the th unit, is the th unit area, is a positive integer; The filling volume is converted into the filling mass, which is expressed by formula (3), and the formula (3) is as follows: ； In formula (3), is the filling quality, is the dry density of the filling material, is the construction loss coefficient.

4. The scour pile foundation reinforcement method based on the MICP curing principle according to claim 1, characterized in that, Formulating grouting parameters according to the initial environmental information includes: Obtaining water flow parameters in a designated area around the pile within a preset period continuously collected by a flow velocity sensor; Establish a flow velocity-time change curve, and align it with the tidal cycle in time series to obtain a flow velocity-tidal change curve; Obtain a first characteristic flow velocity point corresponding to the high slack tide and a second characteristic flow velocity point corresponding to the low slack tide in the flow velocity-tidal change curve; Generate a periodic period corresponding to the safety flow velocity threshold according to the first characteristic flow velocity point and the second characteristic flow velocity point; Generate the grouting window period according to the periodic period; 5. The scour pile foundation reinforcement method based on the MICP curing principle according to claim 1, characterized in that, Formulating the grouting parameters according to the initial environmental information further includes: Obtain the diffusion distribution test data of the grouting liquid at different flow velocities, and construct a flow velocity-effective curing curve of the grouting liquid according to the diffusion distribution test data; Generate a critical flow velocity corresponding to within the range of the preset curing threshold according to the flow velocity-effective curing curve of the grouting liquid; Obtain a preset correction coefficient, and correct the critical flow velocity according to the preset correction coefficient to obtain the safety flow velocity threshold; 6. The scour pile foundation reinforcement method based on the MICP curing principle according to claim 1, characterized in that, Formulating the mixing parameters of MICP according to the initial environmental information includes: Based on the preset salinity-bacterial solution concentration relationship, generate a first reaction concentration range of Bacillus pasteurii according to the seawater salinity; Generate a second reaction concentration range of urea according to the Michaelis-Menten equation; Obtain the water flow parameters to generate a third reaction concentration range of calcium ions; Generate a corrected ratio according to the first reaction concentration range, the second reaction concentration range, and the third reaction concentration range; Prepare the slurry of MICP according to the corrected ratio; 7. The scour pile foundation reinforcement method based on the MICP curing principle according to claim 6, characterized in that Based on the preset salinity-bacterial solution concentration relationship, generating a first reaction concentration range of Bacillus pasteurii according to the seawater salinity includes: Obtain the reference bacterial solution concentration corresponding to the preset reference salinity; Calculate the salinity difference between the seawater salinity and the preset reference salinity; Generate a bacterial solution concentration adjustment amount according to the preset salinity-bacterial solution concentration relationship and the salinity difference; Superimpose the bacterial solution concentration adjustment amount on the reference bacterial solution concentration to generate the first reaction concentration range; Generating a second reaction concentration range of urea according to the Michaelis-Menten equation includes: Obtain the Michaelis constant Km value of Bacillus pasteurii; Calculate the reaction rate at different urea concentrations based on the Michaelis-Menten equation; Select the concentration interval corresponding to when the reaction rate reaches 90% of the maximum rate as the second reaction concentration range; Obtaining the water flow parameters to generate a third reaction concentration range of calcium ions includes: Establish a corresponding relationship model between the flow velocity and the calcium ion concentration; Output the calcium ion concentration interval matching the current flow velocity in the corresponding relationship model according to the water flow parameters as the third reaction concentration range; 8. The scour pile foundation reinforcement method based on the MICP curing principle according to claim 6, characterized in that, Generating a corrected ratio according to the first reaction concentration range, the second reaction concentration range, and the third reaction concentration range includes: Establish a multi-parameter optimization model, and input the first reaction concentration range, the second reaction concentration range, and the third reaction concentration range into the multi-parameter optimization model; Solve the multi-parameter optimization model using the sequential quadratic programming algorithm to obtain the corrected ratio; 9. The scour pile foundation reinforcement method based on the MICP curing principle according to claim 1, characterized in that, Inject the MICP slurry into the soil layer through the grouting assembly according to the grouting parameters, and at the same time obtain the soil resistivity feedback information in the designated area around the pile during the grouting process. Dynamically adjusting the grouting parameters according to the soil resistivity feedback information includes: Obtain the real-time water flow parameters in the defined area around the pile in real time; Adjust the output power of the delivery pump proportionally according to the change of the real-time water flow parameters: When the water flow velocity increases, correspondingly increase the power of the delivery pump; When the flow rate decreases, adjust the power of the delivery pump according to a non-linear relationship; Adopt a staged grouting control procedure, including first-stage grouting and second-stage grouting. The first-stage grouting includes: Adopt a grouting pressure within a first pressure range and a grouting flow rate within a first flow rate range, and keep the urea within a first preset concentration range; Continuously monitor the decreasing rate of the soil resistivity; When the decreasing rate of the soil resistivity is lower than the first-stage threshold, transfer to the second-stage grouting. The second-stage grouting includes: Adopt a grouting pressure within a second pressure range and a grouting flow rate within a second flow rate range, and keep the urea within a second preset concentration range. The first pressure range is lower than the second pressure range, the first flow rate range is higher than the second flow rate range, and the first preset concentration range is lower than the second preset concentration range; Continuously monitor the decreasing rate of the soil resistivity; When the decreasing rate of the soil resistivity is lower than the second-stage threshold, extend the grouting time or add standby grouting points for grouting.

10. The scour pile foundation reinforcement method based on the MICP curing principle according to claim 1, characterized in that, Detect the defined area around the pile to generate a detection result, generate supplementary grouting information according to the detection result, and perform supplementary grouting on local positions in the defined area around the pile according to the supplementary grouting information, including: Conduct sampling detection within a first preset time period after the grouting is completed. The detection items of the sampling detection include calcium carbonate crystallinity and initial soil strength; Divide the risk level according to the first detection result of the sampling detection and generate an intermediate detection strategy. The intermediate detection strategy is configured to record the first detection index during the detection process. The first detection index is the compressive strength and permeability coefficient index; When the first detection index does not meet the preset requirements, collect the position of the first weak area and formulate a supplementary grouting plan. The supplementary grouting plan includes supplementary grouting point distribution information and supplementary grouting parameters. The supplementary grouting parameters include inducer concentration and supplementary grouting pressure; Perform supplementary grouting on the position of the weak area according to the supplementary grouting plan, and conduct verification detection within a second preset time period after the supplementary grouting is completed; Divide the risk level according to the second detection result of the verification detection and generate a standby detection strategy. The standby detection strategy is configured to record the second detection index during the detection process; When the second detection index does not meet the preset requirements, collect the position of the second weak area and formulate a standby supplementary grouting plan; Perform supplementary grouting on the position of the second weak area according to the standby supplementary grouting plan, and conduct verification detection again after the supplementary grouting is completed; Repeat the foregoing verification detection steps until the second detection index meets the preset requirements.

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