Pre-cast concrete pipe pile end post-grouting solidification reinforcement system

Abstract

This invention discloses a post-grouting curing and reinforcement system for precast concrete pipe piles, belonging to the field of post-grouting curing and reinforcement technology for precast concrete pipe piles. The system detects the porosity and permeability distribution fields of the bearing stratum at the pile tip, and extracts nodes to construct a grouting path topology network based on the superimposed distribution map of these fields. The grouting path planning module extracts the local porosity and permeability of each node, substitutes them into a preset adaptation function, and generates segmented values ​​for grouting flow rate and grouting pressure for each node. After grouting, acoustic wave velocity testing is performed to obtain a wave velocity increment distribution map and identify areas with insufficient wave velocity. Then, the volume of the area is obtained based on coordinate positioning, and the weighted replenishment amount is calculated to perform directional replenishment. This system can adapt to the heterogeneity of the stratum to achieve differentiated grouting and performs quantitative replenishment based on detection and positioning, improving the uniformity of soil reinforcement around the pile tip.

Description

Technical Field

[0001] This invention relates to the field of post-grouting curing and reinforcement technology for precast concrete pipe piles, specifically to a post-grouting curing and reinforcement system for precast concrete pipe piles. Background Technology

[0002] In the post-grouting construction of precast concrete pipe piles, grouting parameters are often set based on traditional experience or the overall average physical properties of the pile tip, without fully considering the spatial heterogeneity of the bearing stratum. Because the porosity and permeability coefficient of the bearing stratum at different locations vary significantly, using a uniform grouting flow rate and pressure results in excessive diffusion of the grout in areas with high porosity and strong permeability, while hindering its penetration into areas with low porosity and weak permeability. This leads to uncontrollable solidification of the soil around the pile tip after grouting reinforcement, potentially creating grouting blind zones and ultimately affecting the uniform increase in the pile tip bearing capacity. After grouting, the reinforcement effect is often assessed using core sampling or a small number of sonic tests. Core sampling only reflects the solidification status of isolated sample locations and cannot obtain spatial distribution information on the overall reinforcement quality around the pile tip. While sonic testing based on a small number of points provides some coverage, its accuracy in identifying low-velocity anomaly areas is insufficient, making it difficult to accurately define the true boundary location and volume of areas where grouting has not met standards. When local defects are found, the on-site injection lacks a quantitative injection strategy that combines the original formation properties. The injection volume and direction are judged based on experience, which can easily lead to insufficient injection or waste of slurry. Furthermore, the injection process is not linked to the porosity characteristics of the in-situ formation.

[0003] To address the aforementioned issues, it is necessary to solve the problem of how to differentiate the grouting flow rate and pressure during the grouting process based on the spatial porosity and permeability characteristics of different locations in the pile tip bearing stratum, so that the diffusion degree of the grout in the stratum matches the acceptance capacity of each stratum. Furthermore, it is also necessary to solve the problem of how to accurately identify areas in the soil surrounding the pile tip after grouting solidification that do not meet the wave velocity enhancement requirements, and to determine the amount and direction of additional grout to be injected based on the original stratum porosity information in these areas, thereby achieving targeted directional injection. Summary of the Invention

[0004] The purpose of this invention is to provide a post-grouting curing and reinforcement system for precast concrete pipe piles. This system can adaptively plan the grouting path and dynamically adjust the grouting parameters based on the porosity and permeability distribution of the bearing stratum at the pile end. After grouting, it can locate the replenishment area through sonic detection and perform directional replenishment based on the weight of the replenishment amount calculated according to the porosity of the stratum to improve the uniformity and targeted nature of the grouting reinforcement of the soil around the pile end.

[0005] To achieve the above objectives, the present invention provides the following technical solution: The present invention provides a precast concrete pipe pile post-grouting curing and enhancement system, the system comprising a stratum feature sensing module, a grouting path planning module, a grouting parameter adjustment module, a curing effect feedback module, and a grouting volume replenishment module. The stratum feature sensing module is used to detect the bearing stratum at the pile tip of the target pipe pile, obtaining the stratum porosity distribution field and the stratum permeability coefficient distribution field; the grouting path planning module extracts nodes based on the superimposed distribution map of the stratum porosity distribution field and the stratum permeability coefficient distribution field to construct a grouting path topology network; the grouting path planning module extracts the local porosity and local permeability coefficient of the nodes, substitutes them into preset grouting flow rate adaptation functions and grouting pressure adaptation functions, and generates grouting flow rate segment values ​​and grouting pressure segment values ​​corresponding to each node; the grouting parameter adjustment module extracts the node position coordinates and node connection sequence of each node from the grouting path topology network, and combines them with the corresponding grouting... The flow rate segment values ​​and the grouting pressure segment values ​​form a grouting execution sequence, and the real-time output flow rate and real-time output pressure of the grouting pump are dynamically adjusted according to the grouting execution sequence; the solidification effect feedback module is used to conduct acoustic wave velocity tests on the soil around the pile end after grouting, obtain an acoustic wave velocity increment distribution map, and compare the acoustic wave velocity increment distribution map with a preset wave velocity enhancement threshold to identify areas with insufficient wave velocity; the grouting volume replenishment module locates the area with insufficient wave velocity using spatial coordinates to obtain the area volume, calculates the replenishment volume weight based on the ratio of the area volume to the total porosity corresponding to the area with insufficient wave velocity, and controls the grouting pump to perform directional replenishment according to the replenishment volume weight.

[0006] Through the coordinated work of the above modules, the system can plan differentiated grouting paths based on the actual porosity and permeability characteristics of the bearing stratum at the pile tip, dynamically adjust the flow rate and pressure at each node, make the grout more evenly distributed underground, and use the incremental feedback of sonic wave velocity to solidify weak parts after grouting, automatically calculate the amount of grout to be added and implement directional grouting, thereby ensuring that the soil reinforcement effect around the pile tip fully meets the standards while avoiding excessive grouting.

[0007] As a preferred embodiment of the present invention, the stratum feature sensing module specifically performs the following process: dividing the bearing stratum of the target pipe pile into multiple stratum detection units according to a preset grid size, and performing cross-pore resistivity tomography detection on each stratum detection unit to obtain the resistivity value of each stratum detection unit; normalizing the resistivity value of each stratum detection unit to generate a normalized resistivity value, and inputting the normalized resistivity value into a pre-calibrated porosity-resistivity mapping table for lookup matching, outputting the porosity detection value corresponding to each stratum detection unit, thereby forming the stratum porosity distribution field; simultaneously performing a micro-head permeability test on each stratum detection unit to obtain the permeability coefficient test value of each stratum detection unit, and performing spatial interpolation processing on the permeability coefficient test value to form the stratum permeability coefficient distribution field. The resulting distribution field can reflect the in-situ heterogeneity of the pile tip soil with high resolution, providing a reliable basis for the accurate adaptation of subsequent grouting parameters.

[0008] Preferably, when generating the adaptation function, the grouting path planning module extracts the porosity detection values ​​of all formation detection units in the formation porosity distribution field and calculates their arithmetic mean to obtain the average porosity. Simultaneously, it extracts the permeability test values ​​of all formation detection units in the formation permeability distribution field and calculates their arithmetic mean to obtain the average permeability coefficient. The average porosity is set as the baseline value of the independent variable of the grouting flow rate adaptation function, and the average permeability coefficient is set as the baseline value of the independent variable of the grouting pressure adaptation function. Based on the node position coordinates and node connection order in the grouting path topology network, the module calculates the first ratio of local porosity to average porosity and the second ratio of local permeability coefficient to average permeability coefficient for each node. The grouting flow rate adaptation function and the grouting pressure adaptation function are then adjusted segmentally using the first and second ratios to generate segmented values ​​of grouting flow rate and grouting pressure at each node. In this way, grouting is carried out with a larger flow rate and lower pressure in areas with high porosity and good permeability, while in dense areas it is adjusted to a smaller flow rate and higher pressure, avoiding soil splitting due to excessive pressure or waste of grout due to excessive flow rate.

[0009] Furthermore, before constructing the grouting path topology network, the grouting path planning module performs overlay analysis on the formation porosity distribution field and the formation permeability coefficient distribution field to generate a joint porosity-permeability coefficient distribution map. Contour lines are extracted from this joint distribution map to obtain contour lines for priority grouting areas with high porosity and high permeability, and contour lines for delayed grouting areas with low porosity and low permeability. The center point of the contour lines for the priority grouting areas is set as the starting node of the grouting path topology network, and the center point of the contour lines for the delayed grouting areas is set as the ending node, with the node connection sequence extending from the starting node to the ending node. This method ensures that the grouting process prioritizes filling the seepage-dominant channels and gradually displaces pore water and air into low-permeability areas, significantly improving the overall effective filling rate of the grouting.

[0010] Preferably, the grouting parameter adjustment module inputs the coordinates of each node position and the node connection sequence in the grouting execution sequence to the flow regulating valve controller. The flow regulating valve controller outputs a flow regulating valve opening control command based on the grouting flow segment value corresponding to the current node, so that the opening of the flow regulating valve in the grouting pipeline matches the grouting flow segment value. Simultaneously, it inputs the node position coordinates and the node connection sequence to the pressure regulating valve controller. The pressure regulating valve controller outputs a pressure regulating valve opening control command based on the grouting pressure segment value corresponding to the current node, so that the opening of the pressure regulating valve matches the grouting pressure segment value. This control method achieves automatic variable parameter grouting along the planned path, significantly reducing reliance on operator experience.

[0011] To further optimize the safety of the grouting process, the grouting parameter adjustment module dynamically adjusts the real-time output flow rate and pressure of the grouting pump according to the grouting execution sequence. It collects the real-time feedback pressure value at each node during grouting and calculates the difference between the real-time feedback pressure value and the grouting pressure segment value corresponding to the current node to obtain the pressure deviation value. When the pressure deviation value exceeds a preset pressure deviation threshold, the grouting pump's grouting action is paused, and the pressure relief valve in the grouting pipeline is activated to release pressure until the real-time feedback pressure value falls back to within the allowable error range of the grouting pressure segment value, at which point the grouting pump's grouting action is resumed. This effectively prevents pipeline damage or pile damage caused by abnormal local pressure buildup in the strata.

[0012] Preferably, after grouting, the solidification effect feedback module deploys multiple acoustic wave transmitting probes and multiple acoustic wave receiving probes along a preset annular measuring line around the pile end. Each acoustic wave receiving probe receives acoustic wave signals emitted by each acoustic wave transmitting probe, obtaining a cross-hole acoustic wave velocity test dataset. The cross-hole acoustic wave velocity test dataset is then subjected to tomographic inversion calculation to generate an acoustic wave velocity distribution cloud map of the soil around the pile end. The wave velocity value of each pixel in the acoustic wave velocity distribution cloud map is subtracted from the background wave velocity value at the corresponding location before grouting, resulting in an acoustic wave velocity increment distribution map. The wave velocity increment value of each pixel in the acoustic wave velocity increment distribution map is compared point-by-point with a preset wave velocity enhancement threshold. Pixels with wave velocity increment values ​​less than the wave velocity enhancement threshold are identified as wave velocity deficiency areas. Using acoustic tomography can visually demonstrate the uniformity and integrity of the grouting reinforcement effect with high spatial resolution, and accurately and reliably locate defect areas.

[0013] In this invention, the grouting volume replenishment module locates the identified wave velocity deficiency area using spatial coordinates, obtains the set of boundary coordinate points of the wave velocity deficiency area in three-dimensional space, and calculates the volume of the enclosed area to obtain the wave velocity deficiency area volume. It then extracts the porosity detection values ​​of all formation detection units within the wave velocity deficiency area from the formation porosity distribution field and sums them to obtain the total porosity value of the wave velocity deficiency area. The volume of the wave velocity deficiency area is divided by the total porosity value to obtain the replenishment volume weight. This weight is then multiplied by a preset standard replenishment volume to generate the total replenishment volume for directional replenishment. The grouting pump is then controlled to perform directional replenishment according to this total replenishment volume. The replenishment volume is calculated based on the correlation between volume and total porosity, ensuring that the replenished grout precisely fills the actual pore space, avoiding resource waste and over-grouting caused by blind replenishment.

[0014] Preferably, during directional grouting, the coordinates of the grouting pipe outlet position are obtained, and the spatial geometric relationship between these coordinates and the boundary coordinates of the insufficient wave velocity area is analyzed to determine the spatial vector between the grouting pipe outlet and the center point of the insufficient wave velocity area. Based on the direction of the spatial vector, the orientation of the grout outlet is adjusted so that the axial direction of the outlet coincides with the direction of the spatial vector. The total grouting volume is then segmented according to the spatial distance between the grouting pipe outlet coordinates and the center point of the insufficient wave velocity area, generating segmented grouting flow rates. This allows the grout to be precisely concentrated at the grouting target center, resulting in a concentrated and efficient compensation effect.

[0015] This invention also includes a closed-loop iterative mechanism. After completing the directional injection in all areas with insufficient wave velocity, the solidification effect feedback module performs multi-point acoustic wave velocity testing on the soil around the pile tip again, obtains the distribution map of the increased acoustic wave velocity after injection, and compares it with the preset wave velocity enhancement threshold. If there are still areas with insufficient wave velocity, the spatial coordinate positioning of the areas with insufficient wave velocity, the calculation of injection volume weight, and the directional injection steps are repeated until the wave velocity increment value of all areas is not less than the preset wave velocity enhancement threshold. This closed-loop feedback and iterative injection process ensures that the grouting reinforcement quality meets the standards across the entire area, solves the technical problem that it is difficult to eradicate local weak areas in traditional grouting processes, and makes the improvement of pile tip bearing capacity and overall stiffness more sufficient and reliable.

[0016] The technical effects and advantages provided by the present invention in the above technical solution are as follows: The formation feature sensing module detects the porosity and permeability distribution of the bearing stratum at the pile tip of the target pipe pile, obtaining the formation porosity and permeability distribution fields. The grouting path planning module then uses these two distribution fields as variables to generate grouting flow rate and grouting pressure adaptation functions, and constructs a grouting path topology network. The grouting parameter adjustment module extracts the node position coordinates and node connection sequence from the topology network to form a grouting execution sequence, dynamically controlling the real-time output flow rate and real-time output pressure of the grouting pump. This method, which correlates grouting flow rate and pressure with the local formation porosity and permeability coefficient at specific nodes, is achieved by segmenting the preset grouting flow rate and pressure adaptation functions based on the local physical property parameters of the nodes in the grouting path topology network. Nodes with high porosity and high permeability correspond to higher segmented values ​​for grouting flow rate and pressure, while nodes with low porosity and low permeability correspond to lower segmented values ​​for flow rate and higher segmented values ​​for pressure. This avoids the defects of uniform grouting parameters across the entire area, such as grout flowing along the dominant path and difficulty in injecting into low-permeability areas. It significantly improves the uniformity of grout diffusion in the pile tip bearing layer, reduces grouting blind zones, and results in a more balanced solidification and enhancement effect on the soil around the pile tip. After grouting, the solidification effect feedback module performs multi-point acoustic wave velocity tests on the soil around the pile tip, obtains an acoustic wave velocity increment distribution map, and compares this distribution map point by point with the preset wave velocity enhancement threshold to identify areas with insufficient wave velocity. The grouting volume replenishment module spatially locates areas with insufficient wave velocity, obtains the set of boundary coordinate points of this area, and calculates its volume. Simultaneously, it extracts the porosity values ​​of all formation detection units within the area from the formation porosity distribution field to form the total porosity value for the area with insufficient wave velocity. The ratio of the area volume to the total porosity value is used as the replenishment volume weight to generate the total replenishment volume for directional replenishment and control the grouting pump to perform directional replenishment. This method utilizes the wave velocity increment distribution map obtained from acoustic tomography to accurately identify and define the local locations and extents where grouting solidification has not met standards. The calculation of the replenishment volume weight is directly related to the original formation porosity within the area, ensuring that the replenishment volume matches the actual space that the formation can accept grout. This avoids setting a uniform replenishment volume based on experience, thus preventing discontinuous reinforcement caused by insufficient replenishment and preventing excessive replenishment from causing splitting of the surrounding soil or wasting grout. During the grouting process, the orientation of the grout outlet is adjusted by the spatial vector between the grouting pipe outlet and the center point of the insufficient wave velocity area, and the grouting flow rate is distributed in segments by spatial distance, which further enhances the precise injection and uniform distribution of the grout in the target area. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0018] Figure 1 This is a schematic diagram of the post-grouting curing and reinforcement system for precast concrete pipe piles. Figure 2 This is a flowchart of the formation feature sensing module acquiring the formation porosity distribution field and formation permeability coefficient distribution field; Figure 3 It is a distribution curve of the test values ​​of formation porosity and permeability coefficient; Figure 4 It is a map showing the increase in acoustic wave velocity and the distribution of areas with insufficient wave velocity after the soil around the pile tip has been grouted and solidified. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] See Figure 1This invention provides a post-grouting curing and enhancement system for precast concrete pipe piles, comprising a stratum feature sensing module, a grouting path planning module, a grouting parameter adjustment module, a curing effect feedback module, and a grouting volume replenishment module. The stratum feature sensing module is used to detect the porosity and permeability distribution of the bearing stratum at the pile tip of the target pipe pile, obtaining the stratum porosity distribution field and the stratum permeability distribution field. The grouting path planning module uses the stratum porosity and permeability distribution fields as variables, extracts nodes based on the superimposed distribution map of the stratum porosity and permeability distribution fields, and constructs a grouting path topology network. The grouting path planning module extracts the local porosity and local permeability of the nodes, substitutes them into preset grouting flow rate adaptation functions and grouting pressure adaptation functions, and generates segmented grouting flow rate and grouting pressure values ​​corresponding to each node. The grouting parameter adjustment module extracts the node position coordinates and node connection sequence of each node from the grouting path topology network, combines them with the corresponding grouting flow rate segment value and grouting pressure segment value to form a grouting execution sequence, and dynamically adjusts the real-time output flow rate and real-time output pressure of the grouting pump according to the grouting execution sequence. The solidification effect feedback module performs multi-point acoustic wave velocity testing on the soil around the pile end after grouting, obtains an acoustic wave velocity increment distribution map, compares the acoustic wave velocity increment distribution map with a preset wave velocity enhancement threshold, and identifies areas with insufficient wave velocity. The grouting volume replenishment module locates the spatial coordinates of the areas with insufficient wave velocity, calculates the replenishment volume weight based on the correlation between the spatial coordinate location and the corresponding formation porosity value of the area with insufficient wave velocity, and controls the grouting pump to perform directional replenishment according to the replenishment volume weight.

[0021] Example 1: In specific implementation, please refer to Figure 2 The geological feature sensing module detects the bearing stratum at the pile tip of the target pipe pile, acquiring the distribution fields of soil porosity and soil permeability coefficient. The bearing stratum at the pile tip of the target pipe pile refers to the portion of soil or rock directly bearing the pile tip load below the bottom end of the precast concrete pipe pile.

[0022] In one implementation, the geological feature sensing module divides the bearing stratum of the target pipe pile into multiple geological detection units according to a preset grid size. The preset grid size is determined based on the pile diameter of the target pipe pile and the estimated non-uniformity of the bearing stratum. The geological feature sensing module obtains the pile diameter value of the target pipe pile and multiplies the pile diameter value by a preset scaling factor to obtain the grid edge length. The preset scaling factor ranges from 0.1 to 0.3, and the grid edge length is the preset grid size. Using the center of the pile tip as the origin, a three-dimensional grid is created in both the horizontal and depth directions, with the grid edge length as the step size. Each grid unit is a geological detection unit, and each geological detection unit has unique three-dimensional spatial index coordinates.

[0023] The stratigraphic feature sensing module performs cross-hole resistivity tomography on each stratigraphic detection unit to obtain the resistivity value of each unit. Two or more detection holes are constructed within the pile tip bearing stratum region, with the depth of the holes exceeding the lower boundary of the bearing stratum. A multi-core cable and electrode array are placed in the detection holes, with the electrodes in the array arranged at equal intervals. The stratigraphic feature sensing module controls the electrical resistivity meter to emit a DC signal from one electrode in one detection hole and receive potential signals from electrodes in other holes, cyclically switching the combination of emitting and receiving electrodes to collect potential difference data. The stratigraphic feature sensing module inputs the collected potential difference data and electrode spatial coordinates into an inversion algorithm. The inversion algorithm employs a resistivity tomography method based on finite element forward modeling and least squares inversion to solve for the resistivity value of each stratigraphic detection unit. The resistivity value represents the degree to which the stratigraphic detection unit impedes current conduction, and its unit is ohm-meter.

[0024] The stratigraphic feature sensing module normalizes the resistivity values ​​of each stratigraphic detection unit to generate normalized resistivity values. In one implementation, the normalization process uses the following formula:

[0025] in, This represents the normalized resistivity value, which is a dimensionless value and ranges from 0 to 1. Resistivity value of a stratigraphic unit, expressed in ohm-meter; This represents the minimum resistivity value among all stratigraphic units, expressed in ohm-meters. This represents the maximum resistivity value among all stratigraphic detection units, measured in ohm-meters. The stratigraphic feature sensing module iterates through the resistivity values ​​of all stratigraphic detection units and extracts the minimum resistivity value. and maximum resistivity Then, the resistivity values ​​of each formation detection unit were analyzed. Using the above formula, the normalized resistivity value corresponding to each stratigraphic detection unit is obtained. .

[0026] The stratigraphic feature sensing module inputs the normalized resistivity value into a pre-calibrated porosity-resistivity mapping table for lookup matching, outputting the porosity detection value corresponding to each stratigraphic detection unit. The porosity-resistivity mapping table is pre-calibrated through indoor tests on soil samples from the pile tip bearing stratum. During calibration, resistivity values ​​are tested for soil samples with different porosities, and the resistivity values ​​undergo the same normalization process as described above, establishing a data table corresponding to the normalized resistivity values ​​and porosity detection values. The porosity detection value represents the percentage of pore volume in the total volume of the soil. The stratigraphic feature sensing module uses the normalized resistivity value of each stratigraphic detection unit as an index key, searches the porosity mapping table for the porosity value corresponding to the normalized resistivity value closest to the index key value, and uses the found porosity value as the porosity detection value for that stratigraphic detection unit. The porosity detection values ​​of all formation detection units constitute the formation porosity distribution field, which is stored in the form of a three-dimensional data matrix, where each element is a porosity detection value.

[0027] The formation feature sensing module conducts micro-head permeability tests on each formation detection unit to obtain the permeability coefficient test value for each unit. In one embodiment, the micro-head permeability test employs a borehole micro-head water injection test method. A test section is set up at the location of the formation detection unit, water is injected into the test section, and the change in water head height over time is recorded. By analyzing the water head drop curve, the permeability coefficient test value is calculated using the variable head permeability coefficient calculation formula. The permeability coefficient test value represents the soil's ability to allow fluid to pass through, measured in centimeters per second.

[0028] The formation feature sensing module performs spatial interpolation on the permeability coefficient test values ​​to form a formation permeability coefficient distribution field. In one implementation, the spatial interpolation process uses the Kriging interpolation method. The formation feature sensing module uses the center point coordinates and permeability coefficient test values ​​of each formation detection unit as known sample points, and fits the spatial variation characteristics of the sample points using a variogram model to obtain the variogram parameters. The variogram model can be one of a spherical model, an exponential model, or a Gaussian model. The formation feature sensing module uses the variogram parameters to construct a Kriging equation system, solves for the interpolation weight coefficients, and performs interpolation calculations on the grid nodes within the formation detection unit to obtain a continuously distributed permeability coefficient distribution field. The formation permeability coefficient distribution field is stored in the form of three-dimensional grid data, and the attribute value of each grid node is the interpolated permeability coefficient value.

[0029] Through the above process, the formation feature sensing module obtains the complete formation porosity distribution field and formation permeability coefficient distribution field for subsequent processing.

[0030] See Figure 3In the figure, the horizontal axis represents the horizontal position of the geological exploration unit in the bearing stratum at the pile tip, ranging from 0 to 10 meters; the left vertical axis corresponds to the blue solid curve, representing the porosity detection value in percentage (%); the right vertical axis corresponds to the orange dashed curve, representing the permeability coefficient test value in ×10⁻¹⁰. -4 Centimeters per second (cm / s). This figure reflects the horizontal variation trends of the porosity distribution field and permeability coefficient distribution field obtained by the formation feature sensing module in Example 1 from the detection of the bearing layer at the end of the target pipe pile.

[0031] The curves generally exhibit spatial fluctuations, with porosity values ​​ranging from approximately 27% to 50% and permeability values ​​around 10 × 10⁻⁶. -4 cm / s to 80×10 -4 The porosity varies between cm / s. Specifically, in the range of 0 meters to approximately 1.5 meters, the porosity reading stabilizes at around 42%, and the permeability coefficient remains at 34 × 10⁻⁶. -4 The porosity was around cm / s; in the 1.5-meter to 4.5-meter range, the porosity readings increased significantly and reached a peak of approximately 52%, while the permeability readings also showed a significant increase, peaking at approximately 78 × 10⁻⁶ cm / s. -4 The measured porosity (cm / s) indicates that the strata in this section have well-developed porosity and strong permeability. Between 4.5 meters and 7 meters, both the porosity and permeability coefficient gradually decrease, with the lowest porosity being approximately 33% and the lowest permeability being approximately 12 × 10⁻⁶ cm / s. -4 The porosity (cm / s) indicates that the strata in this section are relatively dense and have low permeability. Between 7 and 10 meters, both porosity and permeability fluctuate slightly, with porosity remaining between 30% and 40% and permeability remaining around 20 × 10⁻⁶. -4 The speed is around cm / s, showing a relatively stable state.

[0032] Example 2: In practical implementation, the grouting path planning module obtains the formation porosity distribution field and formation permeability coefficient distribution field from the formation feature sensing module. The formation porosity distribution field contains the porosity detection values ​​of all formation detection units, and the formation permeability coefficient distribution field contains the permeability coefficient test values ​​of all formation detection units.

[0033] The grouting path planning module extracts the porosity values ​​of all formation detection units in the formation porosity distribution field, sums all the porosity values, and divides the sum by the total number of formation detection units to obtain the average porosity. The average porosity is a single numerical indicator reflecting the overall porosity development degree of the pile tip bearing stratum. Simultaneously, the grouting path planning module extracts the permeability coefficient test values ​​of all formation detection units in the formation permeability coefficient distribution field, sums all the permeability coefficient test values, and divides the sum by the total number of formation detection units to obtain the average permeability coefficient. The average permeability coefficient is a single numerical indicator reflecting the overall permeability performance of the pile tip bearing stratum.

[0034] Before constructing the grouting path topology network, the grouting path planning module performs an overlay analysis on the formation porosity distribution field and the formation permeability coefficient distribution field to generate a joint porosity-permeability coefficient distribution map. In some embodiments, the overlay analysis process is as follows: the porosity detection value of each formation detection unit in the formation porosity distribution field is normalized to obtain a normalized porosity value; the permeability test value of each formation detection unit in the formation permeability coefficient distribution field is normalized to obtain a normalized permeability coefficient value. The normalization process maps the original values ​​to dimensionless values ​​between 0 and 1. Afterwards, the grouting path planning module calculates the joint distribution index for each formation detection unit. The formula for calculating the joint distribution index is:

[0035] in, This represents the joint distribution index, which is dimensionless. This represents the normalized porosity value of a formation detection unit, and is dimensionless. The normalized permeability coefficient of a stratigraphic unit is dimensionless. This represents the porosity weighting coefficient, with a value of 0.5. This represents the permeability weighting factor, with a value of 0.5. Porosity weighting factor. and permeability coefficient weighting coefficient The rationale for setting both to 0.5 is that porosity and permeability coefficient are equally important in evaluating the diffusion and filling capacity of grout in soil, and both jointly determine the priority of grouting. The grouting path planning module will use the calculated joint distribution index... Assign corresponding stratigraphic exploration units, and the joint distribution index of all stratigraphic exploration units constitutes a joint distribution map, namely the porosity-permeability joint distribution map.

[0036] The grouting path planning module extracts contour lines from the porosity-permeability coefficient joint distribution map. Contour line extraction employs either a triangular mesh method or a rectangular mesh method, using the joint distribution index as the field value, and generating contour lines at specified intervals and value sequences. In one implementation, the grouting path planning module sets high-value and low-value thresholds to distinguish between priority grouting areas and delayed grouting areas. The high-value threshold is set to the value of the joint distribution index at the top 20% quantile, and the low-value threshold is set to the value of the joint distribution index at the bottom 20% quantile. Areas with a joint distribution index greater than the high-value threshold are identified as areas with high porosity and high permeability, corresponding to the priority grouting area contour lines; areas with a joint distribution index less than the low-value threshold are identified as areas with low porosity and low permeability, corresponding to the delayed grouting area contour lines. The grouting path planning module extracts the area enclosed by closed contour lines in the priority grouting area contour lines and calculates the centroid coordinates of this area, setting these centroid coordinates as the starting node of the grouting path topology network. Simultaneously, the grouting path planning module extracts the area enclosed by closed contour lines in the delayed grouting area and calculates its centroid coordinates, setting these centroid coordinates as the termination node of the grouting path topology network. The module also extracts intermediate contour lines within the joint distribution index variation area between the priority grouting area contour lines and the delayed grouting area contour lines, at preset joint distribution index intervals. The number of intermediate contour lines is determined based on the joint distribution index variation gradient and the required node density. The centroid coordinates of the area enclosed by each intermediate contour line are calculated, and these coordinates are used as intermediate nodes in the grouting path topology network. The grouting path planning module connects all nodes sequentially according to their corresponding joint distribution index values ​​from high to low, forming a node connection sequence. The direction of the node connection sequence is from the starting node to the termination node. The node position coordinates and node connection sequence thus constructed constitute the grouting path topology network.

[0037] The grouting path planning module sets the average porosity as the baseline value of the grouting flow rate adaptation function. This function adjusts the grouting flow rate based on local porosity changes, with the baseline value corresponding to the base grouting flow rate. The base grouting flow rate is determined empirically based on pile diameter, grout mix ratio, and geological conditions. The grouting path planning module also sets the average permeability coefficient as the baseline value of the grouting pressure adaptation function. This function adjusts the grouting pressure based on local permeability changes, with the baseline value corresponding to the base grouting pressure. The base grouting pressure is calculated based on the formation's bearing capacity and pipeline losses.

[0038] Based on the node location coordinates and node connection order in the grouting path topology network, the grouting path planning module processes each node sequentially. For each node in the topology network, the grouting path planning module extracts the porosity detection value corresponding to the node's coordinates from the formation porosity distribution field as the local porosity, and simultaneously extracts the corresponding permeability test value from the formation permeability coefficient distribution field as the local permeability coefficient. If the node coordinates are not at the center point of the original formation detection unit, the local porosity and local permeability coefficient are obtained through inverse distance interpolation. The grouting path planning module calculates the ratio of the local porosity to the average porosity to obtain a first ratio. A first ratio greater than 1 indicates that the porosity development at the node is higher than the average level, and a first ratio less than 1 indicates that the porosity development at the node is lower than the average level. The grouting path planning module calculates the ratio of the local permeability coefficient to the average permeability coefficient to obtain a second ratio. A second ratio greater than 1 indicates that the permeability at the node is higher than the average level, and a second ratio less than 1 indicates that the permeability at the node is lower than the average level.

[0039] The grouting path planning module uses a first ratio to adjust the grouting flow rate adaptation function in segments, generating segmented grouting flow rate values ​​for each node. The adjustment method is as follows: multiply the base grouting flow rate by the first ratio, and the product is used as the segmented grouting flow rate value for that node. The grouting path planning module uses a second ratio to adjust the grouting pressure adaptation function in segments, generating segmented grouting pressure values ​​for each node. The adjustment method is as follows: multiply the base grouting pressure by the second ratio, and the product is used as the segmented grouting pressure value for that node. Thus, each node obtains corresponding segmented grouting flow rate and grouting pressure values ​​for subsequent grouting operations.

[0040] Example 3: In practical implementation, the grouting parameter adjustment module obtains the grouting path topology network from the grouting path planning module, and extracts the node position coordinates and node connection order of all nodes from the grouting path topology network to form the grouting execution sequence. The grouting execution sequence is an ordered list, in which each element contains the node position coordinates, the corresponding grouting flow rate segment value, and the grouting pressure segment value. The order of the list elements is consistent with the node connection order.

[0041] The grouting parameter adjustment module inputs the coordinates of each node position and the node connection sequence in the grouting execution sequence to the flow regulating valve controller. The flow regulating valve controller is a programmable logic controller (PLC) containing an input interface, a central processing unit (CPU), and an output interface. The input interface receives the node position coordinates and node connection sequence data. The CPU indexes the corresponding grouting flow segment value from the grouting execution sequence based on the current node position coordinates and calculates the flow regulating valve opening control command through a preset flow-opening mapping relationship. The flow-opening mapping relationship is obtained through experimental calibration. Specifically, during the commissioning phase of the grouting pipeline system, the opening of the flow regulating valve is gradually increased from fully closed to fully open in increments. Clean water is injected at each opening value, and the corresponding flow value is recorded, establishing a correspondence table between opening and flow values. In actual operation, the CPU performs a reverse lookup in the opening-flow correspondence table based on the grouting flow segment value to determine the required opening value and converts it into a flow regulating valve opening control command. The output interface transmits the flow control valve opening command to the flow control valve in the grouting pipeline in the form of analog electrical signals or digital communication signals. After receiving the flow control valve opening command, the flow control valve drives the valve core to move to the opening position specified by the command, so that the opening of the flow control valve matches the segmented value of the grouting flow.

[0042] Simultaneously, the grouting parameter adjustment module inputs the coordinates of each node position and the node connection sequence in the grouting execution sequence to the pressure regulating valve controller. The pressure regulating valve controller and the flow regulating valve controller are independently configured in terms of hardware architecture, but share the same node position coordinates and node connection sequence data input. The pressure regulating valve controller indexes the corresponding grouting pressure segment value from the grouting execution sequence based on the current node position coordinates, and calculates the pressure regulating valve opening control command through a preset pressure-opening mapping relationship. The calibration method for the pressure-opening mapping relationship is as follows: During the commissioning phase of the grouting pipeline system, a pressure sensor is installed at the end of the pipeline. The opening of the pressure regulating valve is gradually increased from a fully closed state to a fully open state in increments. Clean water is injected at each opening value, and the pressure value at the end of the pipeline is recorded, establishing a correspondence table between opening values ​​and pressure values. In actual operation, the central processing unit of the pressure regulating valve controller performs a reverse lookup in the correspondence table between opening values ​​and pressure values ​​based on the grouting pressure segment values ​​to determine the required opening value, and converts the opening value into a pressure regulating valve opening control command. The pressure regulating valve controller transmits the pressure regulating valve opening control command to the pressure regulating valve in the grouting pipeline. After receiving the command, the pressure regulating valve drives the valve core to move to the opening position specified by the command, so that the opening of the pressure regulating valve matches the grouting pressure segment value.

[0043] During the dynamic adjustment of the real-time output flow rate and pressure of the grouting pump according to the grouting execution sequence, the grouting pump outputs according to the grouting flow rate segment value and grouting pressure segment value corresponding to the current node in the grouting execution sequence. The grouting parameter adjustment module collects the real-time feedback pressure value at each node. The real-time feedback pressure value is obtained by a pressure sensor installed at the outlet end or end end of the grouting pipeline at a fixed sampling frequency, which is set as a multiple of the grouting pump's operating frequency. The grouting parameter adjustment module calculates the difference between the collected real-time feedback pressure value and the grouting pressure segment value corresponding to the current node to obtain the pressure deviation value. The pressure deviation value is calculated by subtracting the grouting pressure segment value from the real-time feedback pressure value and taking the absolute value.

[0044] The grouting parameter adjustment module has a preset pressure deviation threshold, which is set based on the upper pressure limit of the grouting pipeline system and the allowable fluctuation range of the grouting process. In one embodiment, the pressure deviation threshold is set as a percentage of the grouting pressure segment value. The grouting parameter adjustment module compares the calculated pressure deviation value with the pressure deviation threshold.

[0045] When the pressure deviation exceeds the pressure deviation threshold, the grouting parameter adjustment module executes the overpressure protection procedure. The module sends a pause command to the grouting pump. Upon receiving the pause command, the pump stops its drive motor or closes the feed valve, pausing the grouting operation. Simultaneously, the module sends an open command to the pressure relief valve in the grouting pipeline. This valve is either a solenoid valve or an electrically controlled ball valve. Upon receiving the open command, the pressure relief valve switches from its normally closed state to the open state, allowing the grout in the pipeline to flow back to the storage container or safe discharge point through the pressure relief branch, and the pressure in the pipeline begins to decrease. The grouting parameter adjustment module continuously collects real-time feedback pressure values ​​and calculates the absolute value of the difference between the real-time feedback pressure value and the grouting pressure segment value. When the absolute value of the difference falls back to the allowable error range of the grouting pressure segment value, the module sends a close command to the pressure relief valve, restoring it to its normally closed state; simultaneously, it sends a resume command to the grouting pump, resuming the grouting operation. The allowable error range of the grouting pressure segment values ​​refers to the numerical range obtained by multiplying the grouting pressure segment values ​​by an error coefficient, where the error coefficient is set to a value of 1.

[0046] In some embodiments, after completing the grouting operation of a node, the grouting parameter adjustment module automatically switches to the grouting flow rate segment value and grouting pressure segment value corresponding to the position coordinate of the next node according to the node connection sequence, and repeats the above-mentioned flow regulating valve opening adjustment, pressure regulating valve opening adjustment and overpressure protection process until all nodes in the grouting execution sequence have completed the grouting operation.

[0047] Example 4: In practice, the solidification effect feedback module performs multi-point acoustic wave velocity tests on the soil around the pile end after grouting is completed. Grouting completion means that the grouting pump has completed the grouting operation of all nodes according to the grouting execution sequence, and the grout in the grouting pipeline has stopped flowing and completed initial setting.

[0048] The solidification effect feedback module deploys multiple acoustic wave emitting probes and multiple acoustic wave receiving probes along a pre-set circular survey line around the pile tip. The pre-set circular survey line is a circular trajectory defined on the horizontal plane of the pile tip with a pre-set radius, centered at the center of the pile tip. The pre-set radius is determined based on the pile diameter and the estimated grout diffusion range; the larger the pile diameter, the larger the pre-set radius, ranging from 1.5 to 3 times the pile diameter. The acoustic wave emitting and receiving probes are deployed alternately or in pairs along the pre-set circular survey line at equal arc length intervals. The number of acoustic wave emitting and receiving probes can be the same or different, and they are evenly distributed angularly along the pre-set circular survey line. The deployment depth of each acoustic wave emitting and receiving probe is determined based on the thickness of the bearing stratum at the pile tip, extending downwards from the bottom surface of the pile tip to the bottom boundary of the bearing stratum.

[0049] The curing effect feedback module controls each acoustic wave emitting probe to sequentially emit acoustic signals. The center frequency of the acoustic signal is selected according to the geological characteristics; a low-frequency acoustic signal is used for soil strata, and a high-frequency acoustic signal is used for rock strata. When a single acoustic wave emitting probe is working, all acoustic wave receiving probes simultaneously receive the acoustic signal. Each acoustic wave receiving probe records the time from the start of the acoustic wave emission signal to the arrival of the first wave; this time is called the acoustic wave propagation time. The curing effect feedback module stores the three-dimensional coordinates of the acoustic wave emitting probe, the three-dimensional coordinates of the acoustic wave receiving probe, and the acoustic wave propagation time between them as a ray data point. After all acoustic wave emitting probes have traversed and excited the entire dataset, the curing effect feedback module collects all the ray data, forming a cross-hole acoustic wave velocity test dataset. Each record in the cross-hole acoustic wave velocity test dataset includes the emission coordinates, the receiving coordinates, and the acoustic wave propagation time.

[0050] The solidification effect feedback module performs tomographic inversion calculations on the cross-hole acoustic velocity test dataset. In one implementation, the tomographic inversion calculation employs a ray-tracing tomographic method based on ray theory. The solidification effect feedback module discretizes the three-dimensional space of the soil surrounding the pile tip into inversion grid cells, with each grid cell having the same size as or an integer multiple thereof as the stratigraphic detection cell. An unknown vector is constructed using the center point coordinates of the grid cell and its acoustic velocity value, while a known vector is constructed using the acoustic propagation times of all rays in the cross-hole acoustic velocity test dataset. A travel time equation matrix is ​​then established. The solidification effect feedback module solves the travel time equation matrix using the least squares conjugate gradient method, outputting the acoustic velocity value for each grid cell. The acoustic velocity values ​​of all grid cells are interpolated to generate a continuously distributed acoustic velocity distribution cloud map of the soil surrounding the pile tip.

[0051] The solidification effect feedback module acquires the background wave velocity values ​​of the soil surrounding the pile tip, which were pre-measured and stored before grouting. The background wave velocity values ​​are obtained by conducting cross-hole acoustic wave velocity tests on the soil surrounding the pile tip using the same acoustic probe deployment and data acquisition methods as described above, and then performing tomographic inversion calculations for each inversion grid cell. The solidification effect feedback module subtracts the background wave velocity value at the corresponding three-dimensional spatial location from the wave velocity value of each pixel in the acoustic wave velocity distribution cloud map; the subtraction result is the wave velocity increment value for the corresponding pixel. The wave velocity increment values ​​of all pixels constitute the acoustic wave velocity increment distribution map.

[0052] The solidification effect feedback module stores a preset wave velocity enhancement threshold. This threshold is determined based on the correspondence between the pile foundation bearing capacity design requirements and the wave velocity of the soil after grout solidification. Numerically, it equals the minimum wave velocity increment required for the bearing layer soil at the pile tip to meet the bearing capacity design requirements. The solidification effect feedback module compares the wave velocity increment value of each pixel in the acoustic wave velocity increment distribution map with the wave velocity enhancement threshold point by point. The comparison process involves traversing all pixels in the acoustic wave velocity increment distribution map. For each pixel, it checks if the wave velocity increment value is less than the wave velocity enhancement threshold. If it is, the pixel is marked as a wave velocity deficiency pixel. The solidification effect feedback module performs connectivity analysis on all wave velocity deficiency pixels, merging interconnected wave velocity deficiency pixels into the same region. Each connected wave velocity deficiency region is considered a wave velocity deficiency region, and the set of pixels in the wave velocity deficiency region is output.

[0053] The grouting volume replenishment module obtains the wave velocity deficiency area identified by the curing effect feedback module. The grouting volume replenishment module performs spatial coordinate positioning on the wave velocity deficiency area, obtaining the set of boundary coordinate points of the wave velocity deficiency area in three-dimensional space. In one embodiment, the spatial coordinate positioning steps are: extracting the three-dimensional spatial coordinate values ​​of all pixels in the connected pixel set of the wave velocity deficiency area; using a three-dimensional convex hull algorithm to calculate the outer envelope of the point set, obtaining a polyhedral boundary composed of multiple triangular facets, where the vertex coordinates of each triangular facet are the boundary coordinate points; and after removing duplicate vertex coordinates from all triangular facets, the set of boundary coordinate points of the wave velocity deficiency area is formed.

[0054] The grouting volume replenishment module calculates the volume of the region enclosed by the set of boundary coordinate points to obtain the volume of the region with insufficient wave velocity. The volume calculation employs a three-dimensional geometric volume analytical method or a numerical integration method. In one implementation, the set of boundary coordinate points is divided into multiple tetrahedrons, the volume of each tetrahedron is calculated, and the volumes of all tetrahedrons are summed to obtain the volume of the region with insufficient wave velocity.

[0055] The grouting volume replenishment module extracts the porosity values ​​of all stratigraphic detection units within the insufficient wave velocity region from the stratigraphic porosity distribution field generated by the stratigraphic feature sensing module. The extraction method involves traversing all stratigraphic detection units within the spatial range enclosed by the set of boundary coordinate points of the insufficient wave velocity region, obtaining the porosity value of each detection unit. The grouting volume replenishment module then sums the extracted porosity values ​​of all stratigraphic detection units within the insufficient wave velocity region to obtain the total porosity value for the insufficient wave velocity region.

[0056] The grouting volume replenishment module divides the volume of the insufficient wave velocity region by the total porosity of the insufficient wave velocity region to obtain the replenishment volume weight. The replenishment volume weight reflects the amount of grout required per unit pore volume. Its calculation is expressed by the following formula:

[0057] in, This indicates the weight of the supplementary injection amount, with the dimension being volume (cubic meters). It represents the volume of the region with insufficient wave velocity, and its dimension is volume unit (cubic meter). The average porosity of the region with insufficient wave velocity is a dimensionless ratio, which is the sum of the porosity values ​​of all stratigraphic detection units in the region with insufficient wave velocity divided by the total number of detection units in that region.

[0058] The grouting volume replenishment module stores a preset standard replenishment volume. This standard replenishment volume is a conventional replenishment volume determined based on laboratory grouting tests or historical grouting data. Numerically, it equals the volume of grout required to replenish a unit volume of insufficient area under typical porosity conditions. The grouting volume replenishment module multiplies the weighted replenishment volume by the standard replenishment volume, and the resulting product is the total replenishment volume for directional replenishment.

[0059] During directional grouting, the grouting volume replenishment module acquires the coordinates of the grouting pipe outlet position. These coordinates are obtained via a positioning sensor installed on the grouting pipe or calculated using known geometric parameters of the grouting channel within the pipe pile. The grouting volume replenishment module performs spatial geometric relationship analysis between the grouting pipe outlet coordinates and the boundary coordinate set of the insufficient wave velocity region, determining the spatial vector between the grouting pipe outlet and the center point of the insufficient wave velocity region. The center point of the insufficient wave velocity region is obtained by calculating the centroid coordinates of the boundary coordinate set, which is the arithmetic mean of the three-dimensional coordinates of all points in the boundary coordinate set. The grouting volume replenishment module subtracts the grouting pipe outlet coordinates from the three-dimensional coordinates of the center point of the insufficient wave velocity region to obtain the spatial vector, with the direction of the spatial vector pointing from the grouting pipe outlet to the center point of the insufficient wave velocity region.

[0060] The grouting volume replenishment module adjusts the orientation of the grout outlet of the grouting pipe according to the direction of the spatial vector. The grout outlet of the grouting pipe is equipped with an electrically controlled rotating gimbal or a universal joint. The grouting volume replenishment module converts the direction angle of the spatial vector into angle commands to control the two rotating axes of the gimbal, driving the grout outlet to rotate so that the axial direction of the grout outlet coincides with the direction of the spatial vector.

[0061] Simultaneously, the grouting volume replenishment module calculates the spatial distance between the grouting pipe outlet coordinates and the center point of the insufficient wave velocity area. The module then distributes the total replenishment volume in segments according to the spatial distance, generating segmented replenishment flow rates. The segmentation method is as follows: the total replenishment volume is divided equally into several segments along the spatial distance direction, with each segment allocated an equal replenishment volume. Based on the constant output flow rate at the grouting pipe outlet, the replenishment volume of each segment is converted into a corresponding replenishment time, thereby determining the segmented replenishment flow rate value. This segmented replenishment flow rate value is input as a control command to the grouting pump, causing the pump to output grout in segments as the outlet approaches the target area, completing the directional replenishment.

[0062] See Figure 4The horizontal axis of the graph represents the angle of the circular measuring line, ranging from 0° to 360°, indicating the angular positions of various measuring points along the preset circular measuring line around the pile tip by the solidification effect feedback module. The vertical axis represents the incremental value of the acoustic wave velocity, in meters per second (m / s), indicating the increase in the acoustic wave propagation speed at the corresponding angular position compared to the background wave velocity before grouting. The solid curve in the graph shows the trend of the acoustic wave velocity increment value at each angular position. The red dashed line represents the preset wave velocity enhancement threshold, with a value of 200 m / s, representing the minimum wave velocity increment value required to meet the pile foundation bearing capacity design requirements. The pink filled area in the graph represents the wave velocity increment value below this threshold, i.e., the wave velocity insufficient area, representing the soil section where the pile tip solidification effect has not met the standard.

[0063] As can be seen from the curve changes, the overall wave velocity increment exhibits a periodic fluctuation trend. The peak value reaches nearly 280 m / s, significantly higher than the threshold, indicating good soil consolidation and enhancement in the corresponding angular region. The trough values ​​repeatedly fall below the threshold, dropping to a minimum of approximately 170 m / s, forming two distinct areas of insufficient wave velocity, located at angles of approximately 100° to 140° and 300° to 340° respectively along the circular survey line. The existence of these areas of insufficient wave velocity indicates that the soil consolidation effect at these locations has not met the design requirements, suggesting either insufficient grouting or uneven soil consolidation.

[0064] Example 5: In practice, the solidification effect feedback module and the grouting volume replenishment module work together to execute a closed-loop detection and iterative replenishment process. After the grouting volume replenishment module completes the directional replenishment of all areas with insufficient wave velocity, the solidification effect feedback module conducts multi-point acoustic wave velocity tests on the soil around the pile tip again.

[0065] The implementation method for conducting multi-point acoustic velocity testing again is the same as the initial acoustic velocity testing method after grouting. The solidification effect feedback module deploys multiple acoustic transmitting probes and multiple acoustic receiving probes along a pre-set circular survey line around the pile tip. The position of the pre-set circular survey line, the number of acoustic probes, the deployment depth, and the deployment method are all consistent with the initial test. The acoustic transmitting probes sequentially emit acoustic signals, and all acoustic receiving probes simultaneously receive the acoustic signals, obtaining a cross-hole acoustic velocity test dataset after grouting. The solidification effect feedback module performs tomographic inversion calculations on the cross-hole acoustic velocity test dataset after grouting, generating an acoustic velocity distribution cloud map of the soil around the pile tip after grouting. The inversion algorithm, inversion grid cell size, and solution parameters used in the tomographic inversion calculations are consistent with the initial test. The solidification effect feedback module subtracts the background velocity value at the corresponding spatial location before grouting from the velocity value of each pixel in the acoustic velocity distribution cloud map after grouting, obtaining an incremental acoustic velocity distribution map after grouting.

[0066] The solidification effect feedback module compares the post-injection acoustic velocity increment distribution map with a preset velocity enhancement threshold. The comparison method is as follows: iterate through each pixel in the post-injection acoustic velocity increment distribution map and determine whether the velocity increment value of that pixel is less than the preset velocity enhancement threshold. If no pixel has a velocity increment value less than the preset threshold, the solidification effect feedback module determines that the velocity increment values ​​of the entire area of ​​the soil surrounding the pile tip are not less than the preset threshold, the solidification enhancement effect meets the requirements, and the iteration process terminates.

[0067] If at least one pixel has a wave velocity increment value less than the preset wave velocity enhancement threshold, the solidification effect feedback module will mark the pixel with a wave velocity increment value less than the preset wave velocity enhancement threshold as a new wave velocity insufficient pixel, and perform connectivity analysis on all new wave velocity insufficient pixels. The interconnected new wave velocity insufficient pixels will be merged into a new wave velocity insufficient region, and the pixel set of the new wave velocity insufficient region will be output.

[0068] For new areas with insufficient wave velocity, the grouting volume replenishment module repeatedly performs the spatial coordinate positioning step for these areas. The module extracts the 3D spatial coordinates of all pixels in the connected pixel set of the new insufficient wave velocity area. It then uses a 3D convex hull algorithm to calculate the outer envelope of the point set, obtaining a polyhedral boundary composed of multiple triangular facets. The vertex coordinates of each triangular facet are the boundary coordinate points. After removing duplicate vertex coordinates from all triangular facets, the module forms the boundary coordinate point set of the new insufficient wave velocity area. The grouting volume replenishment module calculates the volume of the area enclosed by the boundary coordinate point set to obtain the volume of the new insufficient wave velocity area.

[0069] The grouting volume replenishment module repeatedly executes the replenishment volume weight calculation step. It extracts the porosity detection values ​​of all formation detection units within the new wave velocity-deficient region from the formation porosity distribution field generated by the formation feature sensing module, and sums the extracted porosity detection values ​​to obtain the new total porosity value for the wave velocity-deficient region. The module then divides the new wave velocity-deficient region volume by the new total porosity value to obtain a new replenishment volume weight. Finally, it multiplies the new replenishment volume weight by a preset standard replenishment volume to generate the new total replenishment volume for directional replenishment.

[0070] The grouting volume replenishment module repeatedly executes the directional replenishment step. It acquires the coordinates of the grouting pipe outlet position during directional replenishment and performs spatial geometric relationship analysis between these coordinates and the boundary coordinates of the new wave velocity deficiency area, determining the spatial vector between the grouting pipe outlet and the center point of the new wave velocity deficiency area. Based on the direction of this spatial vector, the module adjusts the orientation of the grouting pipe outlet to align with the direction of the spatial vector. It then distributes the new replenishment volume in segments according to the spatial distance between the grouting pipe outlet coordinates and the center point of the new wave velocity deficiency area, generating new replenishment flow rate segment values. Finally, it controls the grouting pump to perform directional replenishment according to these new flow rate segment values.

[0071] After completing the directional injection of acoustic velocity in all new areas with insufficient wave velocity, the solidification effect feedback module conducts multi-point acoustic velocity tests on the soil around the pile tip again to obtain the acoustic velocity increment distribution map after the second injection. This map is then compared with a preset wave velocity enhancement threshold. If areas with insufficient wave velocity still exist, the spatial coordinate location, injection volume weight calculation, and directional injection steps for these areas are repeated until, in a comparison of the acoustic velocity increment distribution map after a second injection with the preset wave velocity enhancement threshold, the wave velocity increment value of all pixels is not less than the preset threshold. At this point, the solidification effect feedback module outputs a solidification enhancement compliance signal, and the entire grouting solidification enhancement operation is complete.

[0072] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application.

Claims

1. A precast concrete pipe pile post-grouting curing and strengthening system, characterized in that, The system includes: The formation feature sensing module is used to detect the bearing layer at the pile tip of the target pipe pile and obtain the formation porosity distribution field and formation permeability coefficient distribution field. The grouting path planning module extracts nodes and constructs a grouting path topology network based on the superimposed distribution map of the formation porosity distribution field and the formation permeability coefficient distribution field. The grouting path planning module extracts the local porosity and local permeability coefficient of the nodes, substitutes them into the preset grouting flow rate adaptation function and grouting pressure adaptation function, and generates the grouting flow rate segment value and grouting pressure segment value corresponding to each node. The grouting parameter adjustment module extracts the node position coordinates and node connection order of each node from the grouting path topology network, combines the corresponding grouting flow segment value and grouting pressure segment value to form a grouting execution sequence, and dynamically adjusts the real-time output flow and real-time output pressure of the grouting pump according to the grouting execution sequence. The solidification effect feedback module is used to test the acoustic wave velocity of the soil around the pile end after grouting is completed, obtain the acoustic wave velocity increment distribution map, and compare the acoustic wave velocity increment distribution map with the preset wave velocity enhancement threshold to identify the wave velocity insufficient area. The grouting volume replenishment module locates the area with insufficient wave velocity using spatial coordinates to obtain the area volume, calculates the replenishment volume weight based on the ratio of the area volume to the total porosity corresponding to the area with insufficient wave velocity, and controls the grouting pump to perform directional replenishment according to the replenishment volume weight.

2. The precast concrete pipe pile post-grouting curing and strengthening system according to claim 1, characterized in that, The formation feature sensing module includes the following execution: The bearing layer at the pile tip of the target pipe pile is divided into multiple stratum detection units according to a preset grid size, and cross-hole resistivity tomography is performed on each stratum detection unit to obtain the resistivity value of each stratum detection unit. The resistivity value of each formation detection unit is normalized to generate a normalized resistivity value. The normalized resistivity value is then input into a pre-calibrated porosity-resistivity mapping table for lookup matching. The porosity detection value corresponding to each formation detection unit is output, thereby forming the formation porosity distribution field. A micro-head permeability test is performed on each of the formation detection units to obtain the permeability coefficient test value of each formation detection unit, and the permeability coefficient test value is spatially interpolated to form the formation permeability coefficient distribution field.

3. The precast concrete pipe pile post-grouting curing and strengthening system according to claim 2, characterized in that, The grouting path planning module includes execution: Extract the porosity detection values ​​of all formation detection units in the formation porosity distribution field, and calculate the arithmetic mean of all porosity detection values ​​to obtain the average porosity. At the same time, extract the permeability test values ​​of all formation detection units in the formation permeability distribution field, and calculate the arithmetic mean of all permeability test values ​​to obtain the average permeability. The average porosity is set as the baseline value of the independent variable of the grouting flow rate adaptation function, and the average permeability coefficient is set as the baseline value of the independent variable of the grouting pressure adaptation function. Based on the node location coordinates and node connection order in the grouting path topology network, a first ratio of the local porosity to the average porosity and a second ratio of the local permeability coefficient to the average permeability coefficient for each node are calculated. The grouting flow rate adaptation function and the grouting pressure adaptation function are then adjusted in segments using the first and second ratios to generate segmented values ​​of grouting flow rate and grouting pressure at each node.

4. The precast concrete pipe pile post-grouting curing and strengthening system according to claim 3, characterized in that, The grouting parameter adjustment module includes the following functions: The coordinates of each node position and the node connection sequence in the grouting execution sequence are input to the flow regulating valve controller. The flow regulating valve controller outputs a flow regulating valve opening control command to the flow regulating valve in the grouting pipeline according to the grouting flow segment value corresponding to the current node position coordinate, so that the opening of the flow regulating valve matches the grouting flow segment value. The coordinates of each node position and the node connection sequence in the grouting execution sequence are input to the pressure regulating valve controller. The pressure regulating valve controller outputs a pressure regulating valve opening control command to the pressure regulating valve in the grouting pipeline according to the grouting pressure segment value corresponding to the current node position coordinate, so that the opening of the pressure regulating valve matches the grouting pressure segment value.

5. The precast concrete pipe pile post-grouting curing and strengthening system according to claim 4, characterized in that, The curing effect feedback module includes execution: After grouting is completed, multiple acoustic wave transmitting probes and multiple acoustic wave receiving probes are set up along a pre-set circular measuring line around the soil at the pile end. Each acoustic wave receiving probe receives the acoustic wave signal emitted by each acoustic wave transmitting probe to obtain a cross-hole acoustic wave velocity test dataset. The tomographic imaging inversion calculation is performed on the cross-hole acoustic wave velocity test dataset to generate an acoustic wave velocity distribution cloud map of the soil around the pile end. The wave velocity value of each pixel in the acoustic wave velocity distribution cloud map is subtracted from the background wave velocity value at the corresponding position before grouting to obtain the acoustic wave velocity increment distribution map. The wave velocity increment value of each pixel in the sound wave velocity increment distribution map is compared with the preset wave velocity enhancement threshold point by point, and the area where the wave velocity increment value is less than the wave velocity enhancement threshold is marked as the wave velocity insufficient area.

6. The precast concrete pipe pile post-grouting curing and strengthening system according to claim 5, characterized in that, The grouting volume replenishment module includes the following functions: Spatial coordinate positioning is performed on the region with insufficient wave velocity to obtain the set of boundary coordinate points of the region with insufficient wave velocity in three-dimensional space, and the volume of the region enclosed by the set of boundary coordinate points is calculated to obtain the volume of the region with insufficient wave velocity. The porosity values ​​of all formation detection units in the insufficient wave velocity region are extracted from the formation porosity distribution field, and the porosity values ​​of all formation detection units in the insufficient wave velocity region are summed to obtain the total porosity value of the insufficient wave velocity region. Divide the volume of the wave velocity-deficient region by the total porosity of the wave velocity-deficient region to obtain the replenishment volume weight, and multiply the replenishment volume weight by the preset standard replenishment volume to generate the total replenishment volume for directional replenishment, and control the grouting pump to perform directional replenishment according to the total replenishment volume.

7. The precast concrete pipe pile post-grouting curing and strengthening system according to claim 6, characterized in that, The grouting volume replenishment module includes the following functions: The coordinates of the grouting pipe outlet position during directional injection are obtained, and the spatial geometric relationship between the grouting pipe outlet position coordinates and the boundary coordinate point set of the insufficient wave velocity region is analyzed to determine the spatial vector between the grouting pipe outlet and the center point of the insufficient wave velocity region. Based on the direction of the spatial vector, the orientation of the grout outlet of the grouting pipe is adjusted so that the axial direction of the grout outlet coincides with the direction of the spatial vector. The total volume of the grouting is then divided into segments according to the spatial distance between the grouting pipe outlet coordinates and the center point of the wave velocity deficiency area, generating segmented values ​​for the grouting flow rate.

8. The precast concrete pipe pile post-grouting curing and strengthening system according to claim 7, characterized in that, The grouting path planning module includes execution: Before constructing the grouting path topology network, the formation porosity distribution field and the formation permeability coefficient distribution field are overlaid and analyzed to generate a joint porosity-permeability coefficient distribution map. Contour lines are extracted from the porosity-permeability coefficient joint distribution map to obtain the contour lines of the priority grouting area with high porosity and high permeability, and the contour lines of the delayed grouting area with low porosity and low permeability. The center point of the contour line of the priority grouting area is set as the starting node of the grouting path topology network, and the center point of the contour line of the delayed grouting area is set as the ending node of the grouting path topology network, and the node connection order is from the starting node to the ending node.

9. The precast concrete pipe pile post-grouting curing and strengthening system according to claim 8, characterized in that, The grouting parameter adjustment module includes the following functions: During the process of dynamically adjusting the real-time output flow rate and real-time output pressure of the grouting pump according to the grouting execution sequence, the real-time feedback pressure value at each node during grouting is collected, and the difference between the real-time feedback pressure value and the grouting pressure segment value corresponding to the current node is calculated to obtain the pressure deviation value. When the pressure deviation value is greater than the preset pressure deviation threshold, the grouting pump is paused and the pressure relief valve in the grouting pipeline is activated to release the pressure until the real-time feedback pressure value falls back to the allowable error range of the grouting pressure segment value, and then the grouting pump is resumed.

10. The precast concrete pipe pile post-grouting curing and strengthening system according to claim 9, characterized in that, The curing effect feedback module includes execution: After completing the directional injection in all the areas with insufficient wave velocity, the soil around the pile tip is tested again at multiple points to obtain the distribution map of the incremental wave velocity after injection. The distribution map of the incremental wave velocity after injection is then compared with the preset wave velocity enhancement threshold. If there are still areas with insufficient wave velocity, the steps of spatial coordinate positioning, injection weight calculation and directional injection in the areas with insufficient wave velocity are repeated until the wave velocity increment value of all areas is not less than the preset wave velocity enhancement threshold.

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