Design method and system for correcting and jacking building

Abstract

The invention relates to the technical field, in particular to a building deviation rectification jacking design method and system, and the method comprises the following steps: 1, setting a settlement measurement point; step 2, elevation measurement; step 3, relative elevation determination; step 4, coordinate placement; and 5, fitting a curved surface. According to the method, after jacking deviation correction construction is completed, settlement measurement and gradient measurement are conducted on the building again, and results show that under the condition of slight inclination, the gradient of the building is corrected to be within 0.5%, the requirement that the maximum settlement difference is only 3 mm according to related specifications is met, and under the condition of moderate inclination, the gradient of the building is corrected to be 1.0%. And under the condition of serious inclination, the inclination of the building is corrected to be within 1.5%, the maximum settlement difference is only 8 mm, and the maximum settlement difference is only 10 mm, which are far superior to the settlement condition before construction.

Description

Technical Field

[0001] The present invention relates to the technical field of civil engineering, in particular to a design method and system for correcting and lifting the deviation of a building. Background Art

[0002] Civil engineering is a general term for civil engineering and construction engineering. It is an engineering discipline that builds various facilities and places for human life, production, protection and other activities. It covers the construction of buildings, structures and engineering objects within the facilities and places such as houses, roads, railways, airports, bridges, water conservancy, ports, tunnels, water supply and drainage, protection and other engineering fields above ground, underground, on land, above water and underwater. It includes various technical activities such as survey, design, construction, maintenance and management in the process of engineering construction, as well as the materials, equipment and items consumed in the construction process.

[0003] The invention patent "Jacking and Tilt Correction Construction Method for Solving Uneven Settlement of Buildings" CN117540450A discloses a solution for optimizing the rotation axis. This method determines the point with the minimum settlement value as the tilt correction zero point, selects the point with the maximum settlement value and a randomly selected point to determine the rotation axis, and uses R2 fitting to select the optimal rotation axis. This rotation axis is used to determine the lifting height of the jacking jack, realizing the rigid body rotation with synchronous angular velocity of the entire building, so as to achieve the purpose of overall leveling of the building. The above invention patent is suitable for the situation where the settlement data of a building is close to the same plane after fitting. However, the building is not an absolutely rigid body. The settlement data forms a curved surface of arbitrary shape, which may have individual protrusions or depressions, or even the entire surface is convex or concave. The optimal axis selection should remove points with large discreteness, and after the rotation is completed, the measurement points are distributed appropriately within ±0.00 to achieve the minimum absolute value of the measurement points. Then, fine-tuning is performed on the points with large discreteness according to the stress calculation. During the use of existing buildings, uneven foundation settlement and other reasons often cause the buildings to tilt. Tilted buildings not only affect their appearance and functionality, but may also pose a threat to structural safety. At present, building jacking and correction technology has become one of the important means to solve such problems. Summary of the Invention

[0004] To this end, the present invention provides a design method and system for building deviation correction and jacking to solve the above-mentioned problems.

[0005] The present invention provides the following technical solution: a design method for building deviation correction and jacking, comprising the following steps: Step 1: Settlement measurement points; Step 2: Elevation measurement; Step 3: Determine the relative elevation; Step 4: Coordinate placement; Step 5: fitting the surface; Step 6: Preliminary determination of the rotation axis; Step 7: Rotate and record each point; Step 8: Acquisition of multiple sets of data; Step nine, determining the optimal rotation axis; Step 10, determine the lifting height; Step 11: Real-time monitoring and adjustment of the construction process; Step 12: Fine-tune the points or areas with large discreteness.

[0006] As a preferred solution of the present invention, the steps 1, 2 and 3 are more specifically as follows: Settlement measurement points are set on the ground floor of the building or other planes that should theoretically be at the same horizontal plane at the beginning. According to the shape, size and structural characteristics of the building, settlement measurement points are reasonably arranged at key parts of the building such as the foundation, load-bearing columns, and walls. The arrangement of measurement points should meet the requirements of fully reflecting the settlement status of the building. The spacing between adjacent measurement points is determined according to the scale and complexity of the building. High-precision measuring instruments such as total stations and levels are used to mark and measure the initial positions to ensure the accuracy of the measurement points. Use a level to measure the elevation of each settlement measurement point. During the measurement, ensure that the measurement baseline is established in accordance with the national elevation standard. During the measurement process, record the initial elevation value of each measurement point and take the average value of multiple measurements to improve accuracy. Based on the elevation measurement values of each measuring point, the relative elevation difference between any two points is calculated. Taking a certain benchmark point as the reference point, the elevation difference of other measuring points relative to the benchmark point is calculated, thereby constructing the relative elevation relationship matrix of building settlement.

[0007] As a preferred solution of the present invention, the steps 4, 5 and 6 are more specifically as follows: Taking a corner point of the building as the origin, a rectangular coordinate system is established. The plane position and relative elevation of each settlement measurement point are input into the coordinate system to form a data set. The three-dimensional coordinates of each settlement measurement point are measured using a total station or other measuring equipment to determine the coordinate position of each measurement point in the plane and vertical direction. The measured coordinate data are imported into computer-aided design software or specialized building settlement analysis software for subsequent analysis and processing. First, remove the points in the area with large discreteness and exclude them from the selection of the rotation axis. After the overall jacking and correction are in place, make separate adjustments to the area with large discreteness. Based on the coordinates and relative elevation difference data of multiple measurement points obtained by measurement, use a mathematical fitting algorithm to construct a theoretical surface model of building settlement in the computer. By comparing and optimizing different fitting algorithms, select the fitting method that best suits the building settlement characteristics, so that the fitting surface and the actual settlement situation are optimally matched, and the error is controlled within the error range. On the fitted surface model, the distribution pattern of building settlement is analyzed. According to the shape and inclination trend of the settlement surface, by calculating the main curvature direction and other parameters of the surface, the position of the rotation axis of the building during the overall jacking and correction process is preliminarily determined. The preliminarily determined rotation axis is usually one or a group of spatial straight lines, and its projection position on the plane and the height in the vertical direction are determined according to the settlement situation.

[0008] As a preferred solution of the present invention, the steps 7, 8 and 9 are more specifically as follows: With the preliminarily determined rotation axis as the center, the rotation angle and rotation step are set according to the shape of the fitting surface and the design requirements. According to the set parameters, each settlement measurement point is virtually rotated. During each rotation, the displacement change of each measurement point is accurately recorded. The deformation of the building during the rotation process is intuitively displayed using a computer simulation program, and the results after each rotation are analyzed and evaluated. Repeat step 7 under different rotation parameter combinations to obtain multiple sets of displacement data for each measuring point of the building during the jacking and correction process. By analyzing multiple sets of data, we can understand the influence of factors such as the rotation axis position and rotation angle on the correction effect, providing rich data basis for determining the optimal jacking and correction plan; Multiple sets of data were analyzed and compared, and factors such as the structural safety of the building, the difficulty of construction of the correction effect, etc. were comprehensively considered. From multiple sets of rotation axis candidate schemes, the rotation axis that can make the displacement of each measuring point of the building during the jacking correction process closest to the ideal value and has the least impact on the building structure during construction was screened out as the preferred rotation axis. In the selection process, the weight distribution method was adopted to assign corresponding weights according to the importance of different factors on the correction results, and a comprehensive score was performed to determine the optimal rotation axis.

[0009] As a preferred solution of the present invention, the steps 10, 11 and 12 are more specifically as follows: The ideal lifting height for each measuring point is calculated based on the shape characteristics of the preferred rotation axis and the fitted surface, as well as the amount of tilt that needs to be corrected for the building. A numerical simulation method is used to verify and optimize the calculated lifting height, taking into account the stress and deformation of the building structure at different lifting heights. This ensures that the lifting height meets the correction requirements without compromising the structural safety of the building. When determining the final lifting height, comprehensive adjustments should also be made based on factors such as site conditions and the performance of the lifting equipment. During the jacking and deviation correction construction process, a real-time monitoring system is established, and sensors are used to monitor key parameters of the building, such as the jacking height, horizontal displacement, and stress changes, in real time. The monitoring data is compared with the design values. If the deviation is found to exceed the allowable range, the jacking force or jacking height of the jacking equipment is adjusted in time to ensure that the construction process is carried out according to the design plan. BIM technology is used to dynamically simulate the construction process, intuitively displaying the jacking process and deformation of the building, so that possible problems can be discovered in advance and countermeasures can be formulated; During the overall jacking and correction process, there may be a large deviation between the settlement of individual measuring points or local areas and the overall trend, that is, points or areas with large discreteness. For these points or areas, fine-tuning is carried out by locally increasing or decreasing the jacking amount, adjusting the supporting structure, etc. Special measuring and calibration equipment is used to separately monitor and evaluate these fine-tuning areas to ensure that the fine-tuning process will not have a negative impact on the structural stability of the surrounding areas and the entire building.

[0010] As a preferred solution of the present invention, a building overall jacking and correction design system adopts any one of the building correction and jacking design methods described above, including a settlement measurement point setting module, the output end of the settlement measurement point setting module is electrically connected to an elevation measurement module, the output end of the elevation measurement module is electrically connected to a relative elevation determination module, the output end of the relative elevation determination module is electrically connected to a coordinate placement module, the output end of the coordinate placement module is electrically connected to a rotation axis preliminary determination module, the output end of the rotation axis preliminary determination module is electrically connected to a point rotation and recording module, the output end of the point rotation and recording module is electrically connected to multiple groups of data acquisition modules, the output ends of the multiple groups of data acquisition modules are electrically connected to a preferred rotation axis determination module, the output end of the preferred rotation axis determination module is electrically connected to a jacking height determination module, the output end of the jacking height determination module is electrically connected to a construction process monitoring module, the output end of the construction process monitoring module is electrically connected to an additional stress assessment module, and the output end of the additional stress assessment module is electrically connected to an automation control module.

[0011] As a preferred solution of the present invention, the settlement measurement point setting module is used to set a number of settlement measurement points on the ground floor of the building or other planes that are theoretically initially at the same level, and supports the access of high-precision measurement equipment; The elevation measurement module is used to accurately measure the elevation value of the settlement measurement point and perform data verification and storage; The relative elevation determination module is used to compare the elevation data of each measuring point, set the height of the highest point to zero, and determine the relative elevations of other points relative to the highest point.

[0012] As a preferred solution of the present invention, the coordinate placement module is used to place the plane position and relative elevation of each settlement measurement point in a rectangular coordinate system to form a data set; The rotation axis preliminary determination module is used to select three points that are not in the same straight line, determine the plane formed by the three points, and adjust the plane by a rotation operation until the vertical coordinate height of the three points is zero, thereby determining the intersection of the plane before rotation and the plane after rotation as the rotation axis; The point rotation and recording module is used to rotate the remaining measurement points to the same angle as the plane where the three selected points are located, and record the elevation value of each measurement point after the rotation is completed.

[0013] As a preferred solution of the present invention, the multiple data acquisition module is used to select multiple different groups of three points that are not in the same straight line, and repeatedly perform the operations of the rotation axis preliminary determination module and the point rotation and recording module; The preferred rotation axis determination module is used to compare multiple sets of rotation data and determine the corresponding rotation axis as the preferred rotation axis based on the minimum absolute value of the elevation of each point after rotation. The preferred rotation axis determination module includes a rotation axis comparison program for automatically optimizing the selection of the rotation axis; The lifting height determination module is used to calculate the height change of the coordinates of the lifting displacement control point after rotating around the optimal rotation axis, and use this as the theoretical lifting height of the control point.

[0014] As a preferred solution of the present invention, the construction process monitoring module is used to monitor the building displacement, tilt angle and stress changes in real time during the construction process, and dynamically adjust the jacking parameters; The additional stress assessment module is used to simulate and assess the stress distribution of the building during the jacking process by combining finite element analysis technology to ensure that the additional stress is within a safe range; The automated control module is used to achieve real-time monitoring of settlement measurement points, automatic data collection and transmission, and automatically determine the optimal rotation axis and jacking height through an artificial intelligence algorithm, reducing manual intervention.

[0015] Compared with the prior art, the present invention has the following beneficial effects: 1. In the present invention, after completing the jacking and rectification construction, the settlement and inclination measurements of the building are carried out again. The results show that in the case of slight tilt, the inclination of the building is corrected to within 0.5%, meeting the relevant specifications that the maximum settlement difference is only 3 mm. In the case of moderate tilt, the inclination of the building is corrected to 1.0%. The maximum settlement difference is only 5 mm. In the case of severe tilt, the inclination of the building is corrected to within 1.5%, meeting the requirements of relevant specifications. The maximum settlement difference is only 8 mm. In the case of extreme tilt, the inclination of the building is corrected to within 2.0%, meeting the requirements of relevant specifications. The maximum settlement difference is only 10 mm, which is much better than the settlement condition before construction. The building was inspected for structural safety by a third-party professional organization. The results showed that the structural safety of the building was effectively guaranteed during the jacking and correction process and after the construction was completed. No structural damage or safety hazards occurred. This proves that the method and system have significant effects in improving the structural safety of buildings. Compared with traditional correction methods, the method reduces material consumption, labor costs and equipment rental costs during the construction process, and has significant comprehensive economic benefits. Due to the improved correction accuracy and construction efficiency, the construction period is shortened, which indirectly brings greater economic value.

[0016] 2. In the present invention, the overall jacking and correction design system for the building is based on precise measurement and scientific calculation. Through the collaborative work of a series of modules, it can realize the accurate analysis of the building settlement condition, the optimal design of the jacking scheme and the safety monitoring of the construction process, thereby completing the overall jacking and correction work of the building. The various modules of the system are closely connected and the data is transmitted in an orderly manner, which jointly ensures the efficiency and accuracy of the correction work. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Flow chart of the method of the present invention; Figure 2 This is a flow chart of the system of the present invention. DETAILED DESCRIPTION

[0018] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0019] See also Figure 1-Figure 2 The technical solution provided by the present invention specifically includes the following embodiments: Embodiment: A design method for correcting and lifting a building comprises the following steps: Step 1: Set up settlement measurement points. Set up settlement measurement points on the ground floor of the building or other planes that should theoretically be at the same horizontal plane at the beginning. According to the shape, size and structural characteristics of the building, reasonably arrange settlement measurement points at key parts of the building such as the foundation, load-bearing columns and walls. The arrangement of measurement points should meet the requirements of fully reflecting the settlement status of the building. The spacing between adjacent measurement points should be determined according to the scale and complexity of the building. Use high-precision measuring instruments such as total stations and levels to mark and measure the initial positions to ensure the accuracy of the measurement points. Step 2: Elevation measurement: Use a level to measure the elevation of each settlement measurement point. During the measurement, ensure that the measurement baseline is established in accordance with the national elevation standard to establish the measurement reference surface. During the measurement process, record the initial elevation value of each measurement point, and perform multiple measurements to obtain the average value to improve accuracy. Step 3: Determine the relative elevation. Based on the elevation measurement values of each measuring point, calculate the relative elevation difference between any two points. Taking a certain benchmark as the reference point, calculate the elevation difference of other measuring points relative to the benchmark point, thereby constructing the relative elevation relationship matrix of the building settlement. Step 4: Coordinate placement: Take a corner point of the building as the origin and establish a rectangular coordinate system. Input the plane position and relative elevation of each settlement measurement point into the coordinate system to form a data set. Use a total station or other measuring equipment to perform three-dimensional coordinate measurement of each settlement measurement point, determine the coordinate position of each measurement point in the plane and vertical direction, and import the measured coordinate data into computer-aided design software or specialized building settlement analysis software for subsequent analysis and processing. Step 5: Fitting the surface. First, remove the points in the area with relatively large discreteness and exclude them from the selection of the rotation axis. After the overall jacking and correction are in place, make separate adjustments to the areas with relatively large discreteness. Based on the coordinates and relative elevation difference data of multiple measurement points obtained by measurement, use a mathematical fitting algorithm to construct a theoretical surface model of the building settlement in the computer. By comparing and optimizing different fitting algorithms, select the fitting method that best suits the building settlement characteristics, so that the fitting surface and the actual settlement situation are optimally matched, and the error is controlled within the error range. Step 6: Preliminary determination of the rotation axis. On the fitted surface model, analyze the distribution pattern of building settlement. Based on the shape and inclination trend of the settlement surface, calculate the main curvature direction and other parameters of the surface to preliminarily determine the position of the rotation axis during the overall jacking and correction process of the building. The preliminarily determined rotation axis is usually one or a group of spatial straight lines. Its projection position on the plane and its vertical height are determined according to the settlement situation. Step 7: Rotate and record each point. With the initially determined rotation axis as the center, set the rotation angle and rotation step according to the shape of the fitting surface and design requirements. Perform a virtual rotation operation on each settlement measurement point according to the set parameters. During each rotation, accurately record the displacement change of each measurement point. Use a computer simulation program to intuitively display the deformation of the building during the rotation process, and analyze and evaluate the results after each rotation. Step 8: Acquire multiple sets of data. Repeat step 7 under different rotation parameter combinations to obtain multiple sets of displacement data for each measuring point of the building during the jacking and correction process. By analyzing multiple sets of data, we can understand the influence of factors such as the rotation axis position and rotation angle on the correction effect, providing rich data basis for determining the optimal jacking and correction solution. Step 9: Determine the optimal rotation axis. Analyze and compare multiple sets of data, comprehensively consider factors such as the structural safety of the building, the difficulty of the correction effect, and other factors. From multiple sets of rotation axis candidate schemes, select the rotation axis that can make the displacement of each measuring point of the building during the jacking correction process closest to the ideal value and has the least impact on the building structure during construction as the optimal rotation axis. During the selection process, a weight distribution method is used to assign corresponding weights to different factors according to their importance in affecting the correction results, and a comprehensive score is performed to determine the optimal rotation axis. Step 10: Determine the lifting height. Calculate the ideal lifting height for each measuring point based on the shape characteristics of the preferred rotation axis and the fitted surface, as well as the amount of tilt that needs to be corrected for the building. Use numerical simulation methods to verify and optimize the calculated lifting height by considering the stress and deformation of the building structure at different lifting heights. This ensures that the lifting height meets the correction requirements without compromising the structural safety of the building. When determining the final lifting height, comprehensive adjustments should also be made based on factors such as site conditions and the performance of the lifting equipment. Step 11: Real-time monitoring and adjustment of the construction process. During the jacking and deviation correction construction process, a real-time monitoring system is established. Sensors are used to monitor key parameters of the building, such as the jacking height, horizontal displacement, and stress changes, in real time. The monitoring data is compared with the design values. If the deviation is found to exceed the allowable range, the jacking force or jacking height of the jacking equipment is adjusted in time to ensure that the construction process is carried out according to the design plan. BIM technology is used to dynamically simulate the construction process, intuitively displaying the jacking process and deformation of the building, so as to identify possible problems in advance and formulate countermeasures; Step 12: Fine-tune points or areas with large discreteness. During the overall jacking and correction process, there may be situations where the settlement of individual measurement points or local areas deviates significantly from the overall trend. For these points or areas with large discreteness, fine-tune them by locally increasing or decreasing the jacking amount, adjusting the supporting structure, etc. Use special measurement and calibration equipment to monitor and evaluate these fine-tuning areas individually to ensure that the fine-tuning process does not negatively impact the structural stability of the surrounding areas and the entire building. Develop detailed principles for arranging settlement measurement points based on the building's shape (e.g., rectangular, irregular polygonal, etc.), dimensions (specific parameters such as length, width, and height), and structural characteristics (e.g., structural symmetry, force distribution, etc.). For rectangular buildings, arrange a row of measurement points every x meters along the building's perimeter, and cross-place measurement points every x meters in the vertical and horizontal directions within the building. For buildings with complex structures, more dense measurement points are arranged at key structural stress-bearing locations (e.g., column-beam joints, transfer floors, etc.). In the process of setting up measurement points, the arrangement of measurement points is dynamically adjusted based on the data obtained from preliminary measurements and the actual situation on site. If it is found that the settlement of a certain area is relatively uneven, the density of measurement points in that area can be appropriately increased to more comprehensively reflect the actual settlement situation; After taking multiple measurements and averaging them, conduct a preliminary statistical analysis of the measured data to determine their rationality. If any data deviates significantly from other data and cannot be explained by reasonable reasons, re-measure the measurement point or check whether there is a problem with the measuring equipment. When establishing a measurement datum, not only should the national elevation standards be followed, but the local geographical environment and the special conditions of the measurement site should also be considered. For sites with large undulating terrain, local leveling and calibration of the site are required to ensure the accuracy of the datum. In order to reduce measurement errors during the measurement process, a round-trip measurement method is used, that is, each measurement point is measured repeatedly, and the measurement results are compared and verified. The measuring instrument is calibrated and checked regularly to ensure that the accuracy of the instrument meets the requirements; The measured elevation data is stored in spreadsheets and databases to facilitate subsequent data processing and analysis. Detailed records are created for each measurement point and each measurement result, including measurement time, measurement personnel, measurement instrument number, etc. When selecting a benchmark point, not only the representativeness of its location but also its stability should be considered. A relatively basic and stable part of the building structure should be selected as the benchmark point, such as the base of a foundation column. To improve the anti-interference ability of the benchmark point, multiple mutually verified benchmark points can be used, and the data of the benchmark points can be processed through mathematical methods to improve the reliability of the benchmark point. When calculating relative elevation differences, high-precision mathematical algorithms are used, and strict quality control is applied to the calculation process. Error analysis and verification are performed on the calculation results to ensure that the error is within the allowable range. At the same time, considering the dynamic changes of the building during use, the relative elevation difference is recalculated and analyzed regularly; When establishing a rectangular coordinate system, use advanced measurement and positioning technology, such as a combination of a global positioning system and a total station, to ensure the accuracy of the coordinate system's origin and axis direction. The entire process of establishing the coordinate system is recorded and marked to facilitate subsequent measurement and analysis. When performing three-dimensional coordinate measurement, the influence of factors such as the measurement environment and instrument accuracy is taken into consideration, and the errors in the measurement results are analyzed and compensated. By establishing an error model, the measurement errors caused by factors such as atmospheric refraction and temperature changes are corrected to improve measurement accuracy. Convert the measured coordinate data into a format suitable for computer-aided design software and building settlement analysis software, and integrate it with the elevation measurement data. During the conversion and integration process, the data is strictly checked and processed to avoid data loss or errors; Conduct detailed theoretical analysis and experimental research on different fitting algorithms, such as the least squares method and Bezier surface fitting method, and compare the differences in fitting accuracy and calculation speed among various algorithms. Select the most suitable fitting algorithm based on the characteristics of building settlement data, and optimize and adjust the algorithm parameters to minimize the error between the fitting surface and the actual settlement situation. As the measurement data is continuously accumulated and analyzed, the fitting surface is dynamically updated and verified. At regular intervals or when the accumulated amount of measurement data reaches a certain value, the surface is refitted and compared with the previous fitting results to determine whether the trend and pattern of building settlement are in line with expectations. When calculating parameters such as the principal curvature direction of a surface, more advanced mathematical methods and technical means are used to improve the accuracy and reliability of the calculation results. Numerical calculation software and algorithm libraries are used to numerically solve complex surfaces to obtain more accurate principal curvature directions and values. After determining the preliminary rotation axis, use computer simulation programs and visualization technology to visually display the position and direction of the rotation axis on the building, and compare and verify it with the design expectations. If the rotation axis position is found to be inconsistent with the expectation, analyze the possible reasons and adjust the rotation axis; When setting the rotation angle and rotation step, the structural characteristics and settlement of the building are fully considered, and the rotation parameters are set in detail. Through mechanical analysis of the building structure, the degree of influence of the rotation angle of different parts on the structure is determined, so that the rotation angle and step can be reasonably adjusted to avoid excessive impact on the building structure. During the virtual rotation operation, a computer simulation program is used to monitor the displacement changes of the measuring points in real time, and the data is recorded in real time. Key data during the rotation process are marked and analyzed, such as sudden increases or decreases in the displacement changes of the measuring points at certain specific rotation angles, to provide a basis for subsequent analysis. When selecting three different points that are not in the same straight line to acquire multiple sets of data, a reasonable grouping and combination strategy is adopted to ensure that the acquired data can fully reflect various situations during the building jacking and correction process. Different measurement point combinations are selected according to certain intervals and rules to avoid local duplication or missing data. The acquired multiple sets of data are integrated and analyzed, and data analysis software and algorithms are used to mine and process large amounts of data to extract valuable information and patterns. Through data statistical analysis, machine learning and other methods, the relationship between factors such as the rotation axis position and rotation angle and the correction effect is found, providing a scientific basis for determining the optimal rotation axis. When determining the weights of each factor in the weight distribution method, the specific characteristics of the building and the actual project situation are fully considered. A combination of methods such as expert scoring and hierarchical analysis is used to determine scientific and reasonable weight values. For important public buildings, the weight of structural safety factors may be relatively high, while for some commercial buildings, the weight of construction difficulty factors needs to be given priority consideration. After determining the optimal rotation axis, verify and optimize it through computer simulation programs and numerical analysis methods. Simulate the jacking and deviation correction process under different construction conditions, analyze the rationality and stability of the rotation axis, and fine-tune the rotation axis if necessary to ensure that it can achieve the best effect throughout the deviation correction process. When calculating the theoretical jacking height, a more refined numerical simulation method is used, taking into account the actual structure and material properties of the building, accurately calculating and analyzing key parameters such as stress and strain. Finite element analysis software is used to establish a three-dimensional model of the building, simulating the stress and deformation of the building under different jacking heights, providing a reliable basis for determining the jacking height; The calculated lifting height should be adjusted and controlled on site based on factors such as site conditions and the performance of the lifting equipment. In cases where the site is narrow or the geological conditions are complex, the lifting speed and height should be reasonably controlled to avoid adverse effects on the surrounding environment and the building foundation. In the real-time monitoring system, various sensors (such as displacement sensors, pressure sensors, stress sensors, etc.) are reasonably arranged to ensure that the key parameter data of the building can be fully and accurately collected, and an efficient and stable data collection and transmission system is established to ensure the real-time and integrity of the data; Use BIM technology to conduct a more detailed and intuitive dynamic simulation of the construction process, predict possible problems in advance, and set various conditional trigger mechanisms during the simulation process. When it is found that parameters such as building displacement and tilt angle exceed the set range, early warning signals will be issued in time to remind construction personnel to take corresponding adjustment measures; Develop targeted real-time adjustment strategies based on monitoring data and dynamic simulation results. When it is discovered that a local area of the building is tilted beyond the allowable range, the lifting amount and direction of the lifting equipment are adjusted in a timely manner to put the building back on track; Through data analysis and statistical analysis of monitoring results, data analysis software and algorithms are used to identify points or areas with large discreteness, calculate the coefficient of variation of the displacement data of each measurement point, judge the degree of data dispersion based on the size of the coefficient of variation, and find the measurement location corresponding to the abnormal data point; For the determined discrete points or areas, fine-tuning methods such as locally increasing or decreasing the jacking amount, adjusting the supporting structure, etc. are adopted. During the fine-tuning process, the changes in relevant parameters are monitored in real time, and the fine-tuning effect is evaluated. By comparing the displacement changes of the measuring points before and after fine-tuning, the inclination of the building and other indicators, it is judged whether the fine-tuning has achieved the expected effect. If not, the fine-tuning parameters are further adjusted until the problem is solved.

[0020] Through the above steps one to twelve, after completing the jacking and correction construction, the settlement and inclination measurements of the building were carried out again. The results showed that in the case of slight tilt, the inclination of the building was corrected to within 0.5%, meeting the relevant specifications that the maximum settlement difference is only 3 mm. In the case of moderate tilt, the inclination of the building is corrected to 1.0%. The maximum settlement difference is only 5 mm. In the case of severe tilt, the inclination of the building is corrected to within 1.5%, meeting the requirements of relevant specifications. The maximum settlement difference is only 8 mm. In the case of extreme tilt, the inclination of the building is corrected to within 2.0%, meeting the requirements of relevant specifications. The maximum settlement difference is only 10 mm, which is much better than the settlement condition before construction. The building was inspected for structural safety by a third-party professional organization. The results showed that the structural safety of the building was effectively guaranteed during the jacking and correction process and after the construction was completed. No structural damage or safety hazards occurred. This proves that the method and system have significant effects in improving the structural safety of buildings. Compared with traditional correction methods, the method reduces material consumption, labor costs and equipment rental costs during the construction process, and has significant comprehensive economic benefits. Due to the improved correction accuracy and construction efficiency, the construction period is shortened, which indirectly brings greater economic value.

[0021] A building overall jacking and correction design system adopts any one of the building correction and jacking design methods, including a settlement measurement point setting module, the output end of the settlement measurement point setting module is electrically connected to an elevation measurement module, the output end of the elevation measurement module is electrically connected to a relative elevation determination module, the output end of the relative elevation determination module is electrically connected to a coordinate placement module, the output end of the coordinate placement module is electrically connected to a rotation axis preliminary determination module, the output end of the rotation axis preliminary determination module is electrically connected to a point rotation and recording module, the output end of the point rotation and recording module is electrically connected to multiple groups of data acquisition modules, the output ends of the multiple groups of data acquisition modules are electrically connected to a preferred rotation axis determination module, the output end of the preferred rotation axis determination module is electrically connected to a jacking height determination module, the output end of the jacking height determination module is electrically connected to a construction process monitoring module, the output end of the construction process monitoring module is electrically connected to an additional stress assessment module, and the output end of the additional stress assessment module is electrically connected to an automation control module.

[0022] The settlement measurement point setting module is used to set up several settlement measurement points on the ground floor of the building or other planes that are theoretically initially at the same horizontal plane, and supports the access of high-precision measurement equipment. The elevation measurement module is used to accurately measure the elevation values of the settlement measurement points, and perform data verification and storage. The relative elevation determination module is used to compare the elevation data of each measurement point, set the height of the highest point to zero, and determine the relative elevations of other points relative to the highest point. The coordinate placement module is used to place the plane position and relative elevation of each settlement measurement point in a rectangular coordinate system to form a data set. The rotation axis preliminary determination module is used to select three points that are not in the same straight line, determine the plane formed by these three points, and adjust the plane to zero vertical coordinate height of the three points through rotation operation, thereby determining the intersection of the plane before rotation and the plane after rotation as the rotation axis. The point rotation and recording module is used to make the remaining measurement points rotate the same angle following the plane where the three selected points are located, and record the elevation values of each measurement point after the rotation is completed. The multiple data acquisition module is used to select multiple Three different points that are not in the same straight line are grouped together, and the operations of the preliminary rotation axis determination module and the rotation and recording module of each point are repeatedly executed. The preferred rotation axis determination module is used to compare multiple groups of rotation data, and the corresponding rotation axis is determined as the preferred rotation axis based on the minimum absolute value of the elevation of each point after rotation. The preferred rotation axis determination module includes a rotation axis comparison program for automatically optimizing the selection of the rotation axis. The jacking height determination module is used to calculate the height change of the coordinates of the jacking displacement control point after rotating around the optimal rotation axis, and use this as the theoretical jacking height of the control point. The construction process monitoring module is used to monitor the building displacement, inclination angle and stress changes during the construction process in real time, and dynamically adjust the jacking parameters. The additional stress evaluation module is used to combine finite element analysis technology to simulate and evaluate the stress distribution of the building during the jacking process to ensure that the additional stress is within a safe range. The automation control module is used to realize real-time monitoring of settlement measurement points, automatic data collection and transmission, and automatically determine the optimal rotation axis and jacking height through artificial intelligence algorithm to reduce manual intervention.

[0023] The settlement measurement point setting module rationally arranges settlement measurement points on a plane that is theoretically initially on the same horizontal plane (such as the ground floor of a building) based on the characteristics of building settlement and analysis requirements. It also arranges measurement points at key locations (such as foundations, load-bearing columns, walls, etc.) taking into account the shape, size, and structural characteristics of the building to ensure that the building's settlement status can be fully reflected. The settlement measurement point setting module uses high-precision measuring instruments (such as total stations, levels, etc.) to mark and measure the initial positions of the measurement points. It uses precise coordinate positioning technology to determine the position information of each measurement point in the horizontal and vertical directions, and transmits the data to subsequent modules. The elevation measurement module establishes a unified measurement datum surface according to the national elevation standard as the basis for measuring the elevation of each settlement measurement point. This ensures that the elevation data of different measurement points are comparable and consistent, and accurately obtains the relative elevation information of various parts of the building; The elevation measurement module uses measuring equipment such as a level to perform multiple elevation measurements of each settlement measurement point in accordance with established measurement methods and operating procedures, records each measurement value, and improves measurement accuracy through data statistical methods (such as taking the average value). The measured elevation data is then passed to the relative elevation determination module. Relative elevation determination module: Relative elevation refers to the height difference between each measurement point and the reference point on the selected reference surface. By calculating the relative elevation, the elevation data of each measurement point can be unified into a relative coordinate system, which is convenient for subsequent analysis and processing; The relative elevation determination module compares the elevation data of each measuring point, usually selecting the highest point as the reference point and setting it to zero. It then calculates the height differences of other points relative to the reference point to form a relative elevation relationship matrix, and passes this matrix data to the coordinate placement module. In order to accurately describe and analyze the spatial location information of each measurement point of a building, the coordinate placement module needs to place its plane position and relative elevation in a rectangular coordinate system. This allows the use of mathematical models and algorithms to process and analyze the data, providing a basis for subsequent rotation axis determination and correction calculations. The coordinate placement module establishes a rectangular coordinate system with a corner point of the building as the origin. The plane position (plane coordinates) and relative elevation data of each settlement measurement point are integrated and input into the coordinate system to form a complete data set. The module then uses a total station or other measuring equipment to perform precise three-dimensional coordinate measurement of each measurement point, determine the coordinate position of each measurement point in the plane and vertical direction, and send the obtained coordinate data to the rotation axis preliminary determination module. The module for preliminary determination of the rotation axis, based on the fitted surface model, analyzes the distribution of building settlement and the surface morphology to determine the position of the rotation axis that can effectively control the correction process. The position of the rotation axis is mainly determined by the shape and inclination trend of the settlement surface, and is achieved by calculating parameters such as the main curvature direction of the surface. The module for preliminary determination of the rotation axis selects three points that are not in a straight line, determines the plane formed by these three points, and then adjusts the plane through a rotation operation until the vertical coordinate height of the three points is zero. At this time, the intersection of the plane before and after rotation is the rotation axis. This rotation axis serves as the preliminary correction rotation center, and the relevant parameters are passed to the rotation and recording modules of each point. After determining the initial rotation axis, the point rotation and recording module simulates the displacement changes of each point during the building's jacking and correction process by rotating the remaining measurement points at the same angle along the plane of the selected three points. It also records the elevation values of each measurement point during the rotation process, providing data support for subsequent analysis of the correction effect. The point rotation and recording module performs a virtual rotation operation on each settlement measurement point according to the set rotation parameters (rotation angle and rotation step). Using a computer simulation program, it intuitively displays the deformation of the building during the rotation process, analyzes and evaluates the results after each rotation, accurately records the elevation change information of each measurement point during the rotation process, and transmits the data to multiple data acquisition modules. In order to more comprehensively understand the influence of factors such as the rotation axis position and rotation angle on the correction effect, the multi-data acquisition module needs to obtain multiple sets of displacement data under different conditions. By changing the three points in different groups as the reference, the operations of the rotation axis preliminary determination module and the point rotation and recording module are repeated to obtain multiple sets of displacement data sets. The multi-data acquisition module selects multiple sets of three different points that are not in the same straight line as new rotation reference points, redefines the rotation axis and performs the rotation operation, obtains multiple sets of displacement data of each measuring point of the building during the jacking and correction process, and transmits the multiple sets of data to the optimal rotation axis determination module; The optimal rotation axis determination module analyzes and compares multiple sets of rotation data, taking into account multiple factors (such as the absolute value of the elevation of each point after rotation, the structural safety of the building, the correction effect, the construction difficulty, etc.), and determines the optimal rotation axis as the final solution. This optimal rotation axis can make the displacement of each measuring point in the building jacking correction process closest to the ideal value and minimize the negative impact on the building structure; The optimal rotation axis determination module uses the minimum absolute value of the elevation of each point after rotation as the primary criterion among multiple data sets. Combined with the weight distribution method, it assigns corresponding weights to different factors based on their importance in affecting the correction results, and performs a comprehensive score. The rotation axis comparison program automatically analyzes multiple data sets, selects the rotation axis with the highest score as the optimal rotation axis, and passes the result to the lifting height determination module. The lifting height determination module can calculate the ideal lifting height for each measurement point based on the shape characteristics of the preferred rotation axis and the fitted surface, as well as the amount of tilt that needs to be corrected for the building. However, in actual application, the stress and deformation of the building structure at different lifting heights must also be considered to ensure the safety and reliability of the lifting process. The lifting height determination module uses numerical simulation methods to establish a mechanical model of the building. The relevant parameters of the rotation axis and the fitted surface are input into the model. The height change of each measuring point after rotation around the optimal rotation axis is calculated to obtain the theoretical lifting height of the control point. The stress and deformation of the building under different lifting heights are simulated. The lifting height is verified and optimized through stress analysis and other means to ensure that it meets the correction requirements without causing damage to the building's structural safety. Finally, comprehensive adjustments are made based on factors such as site conditions and the performance of the lifting equipment, and the optimal lifting height data is sent to the construction process monitoring module. The construction process monitoring module monitors key parameters such as building displacement, tilt angle, and stress changes in real time during the jacking and rectification construction process. This is to timely grasp the status of the construction process and ensure that the rectification work is carried out according to the predetermined plan to avoid unexpected situations. By establishing a real-time monitoring system, collecting sensor data, and comparing it with the preset design values, dynamic monitoring of the construction process is achieved. During the construction process, the construction process monitoring module uses various sensors (such as displacement sensors, tilt angle sensors, stress sensors, etc.) to measure the corresponding parameters of the building in real time, and transmits the measured data to the construction process monitoring module. The module analyzes and processes the received data and compares it with the design value. Once the deviation is found to be beyond the allowable range, the lifting force or lifting height of the jacking equipment will be adjusted in time through the automation control module to ensure the safety and stability of the construction process. At the same time, BIM technology is used to dynamically simulate the construction process, intuitively displaying the jacking process and deformation of the building, so as to detect possible problems in advance and formulate countermeasures; Additional stress assessment module During the jacking and correction process, additional stress will be generated inside the building. To ensure the safety of the building structure during construction, it is necessary to simulate and assess the additional stress to ensure that the additional stress is within a safe range. The additional stress assessment module uses finite element analysis technology to establish a three-dimensional finite element model of the building structure. The lifting force and displacement change data of each measurement point during the jacking process are input into the model to simulate the stress distribution of the building at different jacking stages. By analyzing the simulation results, it is evaluated whether the additional stress meets the safety requirements. If not, the information is fed back to the construction process monitoring module and the jacking height determination module to adjust the jacking process. To reduce manual intervention and improve work accuracy and efficiency, the automation control module uses artificial intelligence algorithms to achieve automatic monitoring, data collection and transmission, and automatic determination of the optimal rotation axis and lifting height. The automation control module automatically collects data such as the building's settlement and displacement through the settlement measurement point setting module and other related modules, and uses artificial intelligence algorithms to analyze and process large amounts of data. For example, through machine learning algorithms, it learns the patterns between historical data and monitoring data, predicts the building's deformation trend and the optimal rotation axis, jacking height and other parameters, and automatically adjusts and optimizes the jacking process to ensure the efficient and precise operation of the entire correction work.

[0024] The building's overall jacking and correction design system is based on precise measurements and scientific calculations. Through a series of modules working together, it can achieve accurate analysis of the building's settlement conditions, optimal design of the jacking plan, and safety monitoring of the construction process, thereby completing the building's overall jacking and correction work. The various modules of the system are closely connected and data is transmitted in an orderly manner, jointly ensuring the efficiency and accuracy of the correction work.

[0025] While the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations can be made to the embodiments without departing from the principles and spirit of the invention.

Claims

1. A design method for building deviation correction and jacking, characterized by: The following steps are involved: Step 1: Settlement measurement points; Step 2: Elevation measurement; Step 3: Determine the relative elevation; Step 4: Coordinate placement; Step 5: fitting the surface; Step 6: Preliminary determination of the rotation axis; Step 7: Rotate and record each point; Step 8: Acquisition of multiple sets of data; Step nine, determining the optimal rotation axis; Step 10, determine the lifting height; Step 11: Real-time monitoring and adjustment of the construction process; Step 12: Fine-tune the points or areas with large discreteness.

2. The design method for building deviation correction and jacking according to claim 1 is characterized in that: In the steps 1, 2 and 3, more specifically: Settlement measurement points are set on the ground floor of the building or other planes that should theoretically be at the same horizontal plane at the beginning. According to the shape, size and structural characteristics of the building, settlement measurement points are reasonably arranged at key parts of the building such as the foundation, load-bearing columns, and walls. The arrangement of measurement points should meet the requirements of fully reflecting the settlement status of the building. The spacing between adjacent measurement points is determined according to the scale and complexity of the building. High-precision measuring instruments such as total stations and levels are used to mark and measure the initial positions to ensure the accuracy of the measurement points. Use a level to measure the elevation of each settlement measurement point. During the measurement, ensure that the measurement baseline is established in accordance with the national elevation standard. During the measurement process, record the initial elevation value of each measurement point and take the average value of multiple measurements to improve accuracy. Based on the elevation measurement values of each measuring point, the relative elevation difference between any two points is calculated. Taking a certain benchmark point as the reference point, the elevation difference of other measuring points relative to the benchmark point is calculated, thereby constructing the relative elevation relationship matrix of building settlement.

3. The design method for building deviation correction and jacking according to claim 1 is characterized in that: In the steps 4, 5 and 6, the more specific steps are: Taking a corner point of the building as the origin, a rectangular coordinate system is established. The plane position and relative elevation of each settlement measurement point are input into the coordinate system to form a data set. The three-dimensional coordinates of each settlement measurement point are measured using a total station or other measuring equipment to determine the coordinate position of each measurement point in the plane and vertical direction. The measured coordinate data are imported into computer-aided design software or specialized building settlement analysis software for subsequent analysis and processing. First, remove the points in the area with large discreteness and exclude them from the selection of the rotation axis. After the overall jacking and correction are in place, make separate adjustments to the area with large discreteness. Based on the coordinates and relative elevation difference data of multiple measurement points obtained by measurement, use a mathematical fitting algorithm to construct a theoretical surface model of building settlement in the computer. By comparing and optimizing different fitting algorithms, select the fitting method that best suits the building settlement characteristics, so that the fitting surface and the actual settlement situation are optimally matched, and the error is controlled within the error range. On the fitted surface model, the distribution pattern of building settlement is analyzed. According to the shape and inclination trend of the settlement surface, by calculating the main curvature direction and other parameters of the surface, the position of the rotation axis of the building during the overall jacking and correction process is preliminarily determined. The preliminarily determined rotation axis is usually one or a group of spatial straight lines, and its projection position on the plane and the height in the vertical direction are determined according to the settlement situation.

4. The design method for building deviation correction and jacking according to claim 1 is characterized in that: In the steps 7, 8 and 9, the more specific steps are: With the preliminarily determined rotation axis as the center, the rotation angle and rotation step are set according to the shape of the fitting surface and the design requirements. According to the set parameters, each settlement measurement point is virtually rotated. During each rotation, the displacement change of each measurement point is accurately recorded. The deformation of the building during the rotation process is intuitively displayed using a computer simulation program, and the results after each rotation are analyzed and evaluated. Repeat step 7 under different rotation parameter combinations to obtain multiple sets of displacement data for each measuring point of the building during the jacking and correction process. By analyzing multiple sets of data, we can understand the influence of factors such as the rotation axis position and rotation angle on the correction effect, providing rich data basis for determining the optimal jacking and correction plan; Multiple sets of data were analyzed and compared, and factors such as the structural safety of the building, the difficulty of construction of the correction effect, etc. were comprehensively considered. From multiple sets of rotation axis candidate schemes, the rotation axis that can make the displacement of each measuring point of the building during the jacking correction process closest to the ideal value and has the least impact on the building structure during construction was screened out as the preferred rotation axis. In the selection process, the weight distribution method was adopted to assign corresponding weights according to the importance of different factors on the correction results, and a comprehensive score was performed to determine the optimal rotation axis.

5. The design method for building deviation correction and jacking according to claim 4 is characterized in that: In the steps 10, 11 and 12, the more specific steps are: The ideal lifting height for each measuring point is calculated based on the shape characteristics of the preferred rotation axis and the fitted surface, as well as the amount of tilt that needs to be corrected for the building. A numerical simulation method is used to verify and optimize the calculated lifting height, taking into account the stress and deformation of the building structure at different lifting heights. This ensures that the lifting height meets the correction requirements without compromising the structural safety of the building. When determining the final lifting height, comprehensive adjustments should also be made based on factors such as site conditions and the performance of the lifting equipment. During the jacking and deviation correction construction process, a real-time monitoring system is established, and sensors are used to monitor key parameters of the building, such as the jacking height, horizontal displacement, and stress changes, in real time. The monitoring data is compared with the design values. If the deviation is found to exceed the allowable range, the jacking force or jacking height of the jacking equipment is adjusted in time to ensure that the construction process is carried out according to the design plan. BIM technology is used to dynamically simulate the construction process, intuitively displaying the jacking process and deformation of the building, so that possible problems can be discovered in advance and countermeasures can be formulated; During the overall jacking and correction process, there may be a large deviation between the settlement of individual measuring points or local areas and the overall trend, that is, points or areas with large discreteness. For these points or areas, fine-tuning is carried out by locally increasing or decreasing the jacking amount, adjusting the supporting structure, etc. Special measuring and calibration equipment is used to separately monitor and evaluate these fine-tuning areas to ensure that the fine-tuning process will not have a negative impact on the structural stability of the surrounding areas and the entire building.

6. A building overall jacking and correction design system, using a building correction and jacking design method according to any one of claims 1 to 5, characterized in that: It includes a settlement measurement point setting module, the output end of the settlement measurement point setting module is electrically connected to the elevation measurement module, the output end of the elevation measurement module is electrically connected to the relative elevation determination module, the output end of the relative elevation determination module is electrically connected to the coordinate placement module, the output end of the coordinate placement module is electrically connected to the rotation axis preliminary determination module, the output end of the rotation axis preliminary determination module is electrically connected to the each point rotation and recording module, the output end of the each point rotation and recording module is electrically connected to multiple groups of data acquisition modules, the output ends of the multiple groups of data acquisition modules are electrically connected to the preferred rotation axis determination module, the output end of the preferred rotation axis determination module is electrically connected to the jacking height determination module, the output end of the jacking height determination module is electrically connected to the construction process monitoring module, the output end of the construction process monitoring module is electrically connected to the additional stress assessment module, and the output end of the additional stress assessment module is electrically connected to the automation control module.

7. A building overall jacking and deviation correction design system according to claim 6, characterized in that: The settlement measurement point setting module is used to set a number of settlement measurement points on the ground floor of the building or other planes that are theoretically initially on the same horizontal plane, and supports the access of high-precision measurement equipment; The elevation measurement module is used to accurately measure the elevation value of the settlement measurement point and perform data verification and storage; The relative elevation determination module is used to compare the elevation data of each measuring point, set the height of the highest point to zero, and determine the relative elevations of other points relative to the highest point.

8. The building integral jacking and deviation correction design system according to claim 6, characterized in that: The coordinate placement module is used to place the plane position and relative elevation of each settlement measurement point in a rectangular coordinate system to form a data set; The rotation axis preliminary determination module is used to select three points that are not in the same straight line, determine the plane formed by the three points, and adjust the plane by a rotation operation until the vertical coordinate height of the three points is zero, thereby determining the intersection of the plane before rotation and the plane after rotation as the rotation axis; The point rotation and recording module is used to rotate the remaining measurement points to the same angle as the plane where the three selected points are located, and record the elevation value of each measurement point after the rotation is completed.

9. The building integral jacking and deviation correction design system according to claim 6, characterized in that: The multiple data acquisition module is used to select multiple different groups of three points that are not in the same straight line, and repeatedly perform the operations of the rotation axis preliminary determination module and the point rotation and recording module; The preferred rotation axis determination module is used to compare multiple sets of rotation data and determine the corresponding rotation axis as the preferred rotation axis based on the minimum absolute value of the elevation of each point after rotation. The preferred rotation axis determination module includes a rotation axis comparison program for automatically optimizing the selection of the rotation axis; The lifting height determination module is used to calculate the height change of the coordinates of the lifting displacement control point after rotating around the optimal rotation axis, and use this as the theoretical lifting height of the control point.

10. The building integral jacking and deviation correction design system according to claim 6, characterized in that: The construction process monitoring module is used to monitor the building displacement, tilt angle and stress changes during the construction process in real time, and dynamically adjust the jacking parameters; The additional stress assessment module is used to simulate and assess the stress distribution of the building during the jacking process by combining finite element analysis technology to ensure that the additional stress is within a safe range; The automated control module is used to achieve real-time monitoring of settlement measurement points, automatic data collection and transmission, and automatically determine the optimal rotation axis and jacking height through an artificial intelligence algorithm, reducing manual intervention.

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