A method and system for linkage control of building underpinning and structure reinforcement

Abstract

This application relates to the field of building reinforcement technology, and provides a method and system for coordinated control of underpinning and structural reinforcement in historically protected buildings. Through multi-source sensing modules deployed at the target stress nodes of the original foundation and superstructure of the historically protected building, structural deformation, stress, and crack response data are collected throughout the underpinning construction process, resulting in multi-source monitoring data. A central linkage control module performs comprehensive calculations on the multi-source monitoring data based on a local area comprehensive instability index calculation model, deriving the local area comprehensive instability index and classifying the instability level of the local area. Based on the instability level, underpinning force adjustment commands and reinforcement constraint strengthening commands are generated based on an underpinning and reinforcement stiffness matching calculation model, driving the underpinning execution module and the reinforcement execution module to perform coordinated execution. This invention solves the problems of phased implementation of underpinning and reinforcement, disconnection of actions at both ends under sudden instability, and stress redistribution imbalance easily leading to structural cracking and irreversible weathering damage.

Description

Technical Field

[0001] This invention belongs to the field of building reinforcement technology, specifically relating to a method and system for linkage control of historical building underpinning and structural reinforcement. Background Technology

[0002] Historic buildings (hereinafter referred to as historical buildings) are important material carriers of urban cultural heritage, bearing the historical memory and distinctive features of a region. With the advancement of urban renewal, there is an increasing number of engineering activities such as the development of existing underground spaces, the construction of surrounding foundation pits, and the upgrading of infrastructure. Many historical buildings require foundation replacement and structural reinforcement to eliminate safety hazards and adapt to new usage needs. Especially in areas with widespread soft soil, the replacement process is prone to sudden events such as localized soil softening, abrupt settlement of old foundations, and fluctuations in groundwater levels, influenced by regional hydrogeological conditions. Historical buildings themselves have high levels of structural damage and weak deformation tolerance; sudden instability can easily lead to irreversible damage such as wall cracking and structural deformation, placing extremely high demands on the precision and safety of construction management.

[0003] However, conventional engineering projects generally adopt a phased design and sequential implementation approach, involving foundation replacement and superstructure reinforcement. While this can meet the basic requirements for improving bearing capacity and strengthening the structure under stable construction conditions, when abnormal conditions such as sudden settlement or stress changes occur in a local foundation, the stress adjustment at the lower replacement end and the constraint reinforcement at the upper reinforcement end cannot be synchronized. The stress redistribution between the old and new structures is not effectively controlled, directly leading to problems such as rapid expansion of wall cracks and aggravated differential settlement of the building. This causes irreversible structural damage and destruction of the historical appearance of the already damaged and weakly deformation-resistant historical buildings.

[0004] Meanwhile, existing monitoring methods mostly use single-parameter independent threshold judgment methods, which are easily affected by construction vibration and environmental interference, resulting in misjudgment and omission. They cannot quantify the overall instability of the area and are lagging in the identification of gradual instability trends. Sudden instability handling relies on manual experience for adjustment, and the matching degree between replacement and reinforcement actions is poor, which can easily lead to additional structural deformation and secondary damage. Moreover, the existing replacement system has insufficient safety redundancy, and the recovery process after instability handling can easily cause secondary stress fluctuations.

[0005] Therefore, there is an urgent need for a construction management technology that can automatically identify sudden instability of local foundations, coordinate the execution of underpinning and reinforcement, provide safety guarantees for extreme working conditions, and facilitate smooth resumption of work. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide a method and system for the linkage control of underpinning and structural reinforcement in historical buildings. This will solve the technical problems in the current construction of historical buildings where underpinning and reinforcement are carried out in separate steps, the two ends of the action are disconnected under sudden instability, and the stress redistribution is unbalanced, which easily leads to structural cracking and irreversible weather damage.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] Firstly, this invention proposes a method for coordinated control of underpinning and structural reinforcement in historically preserved buildings, comprising the following steps: S1, Data Acquisition: Multi-source sensing modules deployed at target stress nodes of the original foundation and superstructure of the historically preserved building are used to collect structural deformation, stress, and crack response data throughout the underpinning construction process, obtaining multi-source monitoring data, which is then transmitted to a central coordinated control module; S2, Instability Determination: The central coordinated control module, based on a built-in local area comprehensive instability index calculation model, performs comprehensive calculations on the multi-source monitoring data to obtain a local area comprehensive instability index, and classifies the instability level of the local area accordingly; S3, Hierarchical Coordinated Control: Based on the instability level, the central coordinated control module, based on the built-in... The set-up underpinning and reinforcement stiffness matching calculation model generates underpinning force adjustment commands and reinforcement constraint strengthening commands. It drives the underpinning execution module set in the stable soil layer below the original foundation to adjust the underpinning force distribution at each underpinning point, and drives the reinforcement execution module set in the upper wall and column to adjust the structural reinforcement constraint strength, realizing the dual-end linkage execution of underpinning end unloading and reinforcement end crack limiting; S4, state verification and step-by-step callback: After the control execution, the structural state is continuously verified. If the structural state is not stable, return to step S1 for continuous monitoring and control; when the comprehensive instability index of the local area is stable in the safe range for several consecutive fixed monitoring cycles and there is no upward trend, the step-by-step callback is executed in the order of underpinning first and then reinforcement, step-by-step reduction, and segment-by-segment verification to restore normal construction.

[0009] Furthermore, the target stress nodes refer to the stress-bearing parts that are most indicative of local instability in the structural response during the underpinning construction process, specifically including the original foundation top surface, column base, mid-span and support sections of the underpinning beam, load-bearing sections of the wall, column body, roof truss nodes, and the ends of existing cracks and easily cracked parts; each monitoring unit of the multi-source sensing module is correspondingly deployed at the above-mentioned target stress nodes.

[0010] Further, after step S1 and before step S2, the central linkage control module sequentially performs outlier removal, smoothing filtering, and spatial coordinate matching on the multi-source monitoring data: outlier removal filters out jump data caused by construction vibration, smoothing filtering eliminates random data fluctuations, and spatial coordinate matching associates the original foundation deformation data, underpinning force data, and superstructure response data of the same local area one by one to construct an integrated data mapping relationship and obtain standardized multi-source monitoring data; in step S2, the standardized multi-source monitoring data is comprehensively calculated.

[0011] Furthermore, the local regional comprehensive instability index calculation model adopts multi-parameter normalized weighted calculation, and the calculation formula is as follows:

[0012]

[0013] In the formula: This refers to the comprehensive instability index of the local area. The measured value of the settlement of the original foundation within the fixed monitoring period; The baseline allowable value for basic settlement; The measured value of the stress increment of the supporting beam within the fixed monitoring period; This is the allowable value for stress increment; The measured value of crack propagation within the fixed monitoring period; W1 represents the baseline allowable value for crack propagation; W2 and W3 are the weighting coefficients for settlement, stress, and crack propagation, respectively. Each normalized ratio in this formula is dimensionless. When the measured values ​​of the three parameters simultaneously reach their respective baseline allowable values... =1, therefore =1.0 corresponds to the weighted allowable limit state, which is set as the critical value and is physically self-consistent; each measured value is taken as the most unfavorable value of the same type of measuring point in the corresponding local area, that is, the maximum value, to ensure the conservatism and safety of the local instability judgment.

[0014] Furthermore, the instability level includes primary instability and advanced instability; in step S2, the ratio of the measured value of each single parameter to the corresponding benchmark allowable value is calculated, and each ratio is compared with the initial warning value. When each ratio is lower than the initial warning value, normal monitoring is maintained. When any ratio reaches the initial warning value, the local area comprehensive instability index is calculated, and trend analysis is performed on the local area comprehensive instability index for multiple consecutive fixed monitoring periods. When the local area comprehensive instability index is in the warning range and the change is maintained within the preset range, it is determined to be primary instability. When the local area comprehensive instability index exceeds the warning limit or shows a continuous upward trend, it is determined to be advanced instability.

[0015] Preferably, the initial warning value is 0.7; the warning interval is the interval where the comprehensive instability index of the local area is greater than or equal to 0.7 and less than 0.9; the warning limit is 0.9; the critical value is 1.0; the interval where the comprehensive instability index of the local area is lower than the initial warning value of 0.7 is the safe interval referred to in step S4; the criterion for maintaining the change within the preset range can be that the increment of the comprehensive instability index of the local area does not exceed 0.03 for two consecutive fixed monitoring cycles; the criterion for continuous increase can be that the comprehensive instability index of the local area increases period by period for three consecutive fixed monitoring cycles.

[0016] Further, in step S3, if the instability is determined to be primary, the construction pace is slowed down, the reinforcement execution module is driven to strengthen the structural reinforcement constraints, and the underpinning execution module is driven to fine-tune the underpinning force. Then, the change of the comprehensive instability index of the local area is tracked. When the comprehensive instability index of the local area falls, observation is maintained. When the comprehensive instability index of the local area rises, the process returns to step S2 to re-determine the instability. If the instability is determined to be advanced, the construction work is suspended, the reinforcement execution module is driven to initiate directional grouting reinforcement of the foundation and walls of the local area and strengthen the structural reinforcement constraints, and the multiple underpinning points of the underpinning execution module are driven to transfer the load in a coordinated manner.

[0017] Furthermore, the stiffness matching calculation model for the underpinning reinforcement is established based on the principles of stiffness equivalence and deformation compatibility, and the calculation formula is as follows:

[0018]

[0019] In the formula: Adjust the preload increment of the upper reinforcing component of the reinforcement execution module; The adjustment amount of the supporting force at the supporting points in the local area; This refers to the equivalent deformation stiffness of the superstructure in the local area. The equivalent vertical stiffness of the foundation underpinning system corresponding to the local area; For historical building protection correction factors;

[0020] The adjustment amount of the supporting force at the supporting points in the local area The bearing capacity is determined based on the soil softening loss in the local area; when multiple underpinning points in the local area are adjusted in a coordinated manner, the sum of the underpinning force adjustments at each underpinning point is equal to... Furthermore, the adjustment amount of the replacement force at each replacement point is distributed according to the distance from the center of instability.

[0021] This formula is derived from the deformation compatibility condition: the additional displacement at the underpinning point caused by the adjustment of the underpinning force is... and The ratio, in order to coordinate the constraint deformation of the superstructure with the additional displacement, requires a preload adjustment increment of . The product of this additional displacement and the historical building protection correction factor k is then introduced to obtain the result. and The ratio is a dimensionless quantity, and both sides of the formula equation are forces, so the dimensions are consistent.

[0022] Furthermore, the protection correction coefficient k for historically protected buildings is greater than 0 and less than or equal to 1; for ordinary buildings, k can be taken as 1. For historically protected buildings, due to material weathering, low mortar strength, and weak deformation resistance, excessive active pre-tightening may crush the mortar joints and cause secondary damage, so k is taken as less than 1; k is determined based on the building protection level and the test results of the residual strength of the material. The higher the protection level and the more serious the degradation of material performance, the smaller the value of k should be. For secondary protection brick and wood structures, k should be taken as 0.6 to 0.8.

[0023] Furthermore, the equivalent vertical stiffness of the foundation underpinning system corresponding to the local region. The following parameters were determined through a trial jacking test: incremental jacking force was applied in stages, and the corresponding displacement increments were recorded; the slope of the linear segment of the force-displacement curve was taken; the equivalent deformation stiffness of the superstructure in the local area was determined. The determination can be made by establishing a numerical model of the superstructure of the local area, or by applying a small amount of test tensioning force on site and measuring the structural deformation for back calculation.

[0024] Furthermore, the adjustment amount of the supporting force at the supporting points in the local area. The bearing capacity is determined based on the soil softening loss in the local area; when multiple underpinning points in the local area are adjusted in a coordinated manner, the sum of the underpinning force adjustments at each underpinning point is equal to... Furthermore, the adjustment amount of the underpinning force at each underpinning point is distributed according to its distance from the instability center. The instability center refers to the location where deformation and stress response are most concentrated within the local area, which can be the location of the measuring point corresponding to the most unfavorable measured value used in the calculation of the comprehensive instability index of the local area. The total load of the area is determined by the self-weight of the superstructure and the service load. The adjustment only changes the proportion of the load at each underpinning point. Therefore, the sum of the adjustment amounts at each underpinning point is conserved, avoiding additional differential settlement caused by increases or decreases between points.

[0025] Furthermore, when executing the control command in step S3, the timing control logic of strengthening before replacement is followed: the strengthening execution module is driven first to reinforce the structural reinforcement constraints; after the structural reinforcement constraints reach the target value, the replacement execution module is driven to adjust the replacement force; both the replacement force adjustment and the structural reinforcement constraint strengthening are executed in a uniform and gradual manner; the preload application rate should not exceed 5 kN per minute, and the replacement force adjustment rate should not exceed 2 kN per minute; and a logic interlock mechanism is set up so that when the structural reinforcement constraints are not adjusted in place, the replacement end is prohibited from performing large-scale replacement force adjustments, and the single-level replacement force adjustment amount at the replacement end should not exceed 10%.

[0026] Furthermore, during the execution of steps S3 and S4, emergency conditions are assessed in real time. When the hydraulic pressure of the replacement execution module is abnormal, the comprehensive instability index of the local area reaches a critical value, or a manual locking command is received, the safety self-locking module linked to the replacement execution module is triggered to lock the replacement force of the replacement execution module. The triggering priority, from high to low, is: abnormal hydraulic pressure triggering, comprehensive instability index of the local area reaching a critical value triggering, and manual locking command triggering. When locking is triggered, the hydraulic circuit of the replacement execution module is locked first to maintain the replacement force. When the hydraulic system fails, the rigid self-locking structure engages to lock and bear the vertical load. Directional grouting can continue in the locked state to solidify the softened soil and restore the bearing capacity of the foundation.

[0027] Furthermore, the preferred triggering condition for the step-by-step callback in step S4 is that the comprehensive instability index of the local area remains stable within the safe range for six consecutive fixed monitoring cycles without an upward trend, and the directional grouting slurry has solidified and the foundation bearing capacity has recovered. During the callback, the adjustment amount is reduced by 20% at each level, and the structural response data is checked for one fixed monitoring cycle after each level of adjustment is completed. If the comprehensive instability index of the local area rises back to the warning range during the check, the callback is suspended and the status is restored to the previous level. After the callback is completed, normal monitoring and normal construction are resumed, and the entire process handling data is retained for model optimization and project review.

[0028] Furthermore, the method is implemented by dividing the building longitudinally into several independent control zones. Each control zone is a local area for instability judgment and linkage control. Each local area is equipped with a linkage unit consisting of sensing points, replacement points and reinforcement components. Each local area is independently controlled and the data of the whole area is interconnected.

[0029] Furthermore, the multi-source sensing module includes a deformation monitoring unit, a stress monitoring unit, an attitude monitoring unit, and a crack monitoring unit. The deformation monitoring unit is deployed on the top surface of the original foundation, column bases, and key sections of the underpinning structure to collect vertical settlement and horizontal displacement data. The stress monitoring unit is deployed on the underpinning components and the load-bearing sections of the superstructure to collect structural stress data. The attitude monitoring unit is deployed in layers along the building height at the joints of walls, columns, and roof trusses to collect structural tilt and rotation data. The crack monitoring unit is deployed along the crack direction at the ends of existing cracks and easily cracked areas to collect crack width and expansion data. Each monitoring unit is networked according to local areas, and sampling is triggered by a unified clock. Data is transmitted in a wired and wireless redundant manner. Low-frequency sampling is performed under normal monitoring conditions, and the sampling frequency is increased when primary instability or higher levels are determined.

[0030] Furthermore, the underpinning execution module includes an underpinning bearing unit, a jacking adjustment unit, and an underpinning beam unit. The underpinning bearing unit is statically implanted into the stable soil layer to reduce construction disturbance. The underpinning beam unit is fitted under the original foundation, and the contact surface between the underpinning beam unit and the original foundation is densely filled with micro-expansion material to evenly distribute the load of the original foundation to each underpinning point. The jacking adjustment unit is independently set for each underpinning bearing unit and uses graded pressure adjustment to achieve smooth adjustment of the underpinning force. Each jacking adjustment unit is connected to the central linkage control module, and the underpinning force data is transmitted back throughout the adjustment process to form a closed-loop verification of command execution.

[0031] Furthermore, the reinforcement execution module includes an embedded reinforcement unit, a constraint adjustment unit, and a directional grouting unit. The embedded reinforcement unit is installed inside the wall and around the column by drilling, without damaging the building's exterior appearance. The constraint adjustment unit is connected to the embedded reinforcement unit and adjusts the pre-tightness through a mechanical tensioning mechanism to apply active constraints to limit crack propagation. The directional grouting unit includes a foundation grouting pipeline arranged in a fan shape towards the softened foundation area and a wall grouting pipeline arranged along the wall mortar joints. The reinforcement components of each local area are independently controllable and form a vertical linkage control combination with the corresponding underpinning points.

[0032] Secondly, the present invention also proposes a linkage control system for historical building underpinning and structural reinforcement, used to realize the linkage control method for historical building underpinning and structural reinforcement described in the first aspect, including a multi-source sensing module, an underpinning execution module, a reinforcement execution module, a central linkage control module, and a safety self-locking module.

[0033] The multi-source sensing module is deployed at the target stress nodes of the original foundation and superstructure of the historical building to collect structural deformation, stress and crack response data throughout the entire underpinning construction process, thereby obtaining multi-source monitoring data.

[0034] The underpinning execution module is located in the stable soil layer below the original foundation and is used to bear the vertical load of the historical building and dynamically adjust the underpinning force distribution at the underpinning point.

[0035] The reinforcement execution module is deployed on the upper wall and column parts to apply structural reinforcement constraints and dynamically adjust the strength of the structural reinforcement constraints.

[0036] The central linkage control module is connected to the multi-source sensing module, the underpinning execution module, the reinforcement execution module, and the safety self-locking module. It has a built-in local area comprehensive instability index calculation model and underpinning and reinforcement stiffness matching calculation model. It is used to comprehensively calculate the multi-source monitoring data, obtain the local area comprehensive instability index and classify the instability level of the local area. Based on the stiffness matching principle, it generates underpinning force adjustment command and reinforcement constraint strengthening command, driving the underpinning execution module and the reinforcement execution module to execute in linkage.

[0037] The safety self-locking module is linked with the replacement execution module and is used to lock the replacement force of the replacement execution module in emergency situations.

[0038] Furthermore, the safety self-locking module includes a hydraulic locking unit, a mechanical locking unit, and an emergency triggering unit. The hydraulic locking unit is a normally closed hydraulic lock connected to the hydraulic circuit of the replacement execution module. After triggering, it locks the oil circuit to maintain the replacement force. The mechanical locking unit is a rigid self-locking structure, which is configured in conjunction with the lifting adjustment unit of the replacement execution module to engage and lock in case of hydraulic failure and to bear vertical loads. The emergency triggering unit has multiple triggering logics. Locking can be triggered by abnormal hydraulic pressure, the comprehensive instability index of the local area reaching a critical value, and a manual locking command. The triggering priority is from high to low as follows: abnormal hydraulic pressure triggering, comprehensive instability index of the local area reaching a critical value triggering, and manual locking command triggering.

[0039] Furthermore, the central linkage control module includes a data processing unit, an instability determination unit, an instruction generation unit, a timing control unit, a callback control unit, and a storage unit. The data processing unit is located at the module input end, performing outlier removal, smoothing filtering, and spatial coordinate matching, and outputting standardized multi-source monitoring data. The instability determination unit has a built-in local area comprehensive instability index calculation model, performing single-parameter preliminary judgment, local area comprehensive instability index calculation, trend analysis, and level classification. The instruction generation unit has a built-in underpinning and reinforcement stiffness matching calculation model, generating underpinning force adjustment instructions and reinforcement constraint strengthening instructions according to the instability level. The timing control unit manages the action sequence, rate matching, and logic interlocking of both ends. The callback control unit restores normal construction according to step-by-step callback logic. The storage unit retains the monitoring and handling data of the entire process.

[0040] It should be noted that the specific threshold, weight coefficient, correction coefficient, fixed monitoring period, number of callback periods, and reduction ratio involved in the instability determination in this invention are all preferred parameters. In actual engineering, they can be adjusted according to the building protection level, structural type, and monitoring conditions. All equivalent substitutions based on the calculation model and linkage control logic of this invention should fall within the protection scope of this invention.

[0041] The beneficial effects of this invention are as follows: Through a multi-source sensing, underpinning execution, reinforcement execution, central control, and safety self-locking integrated linkage control architecture, combined with a local area comprehensive instability index algorithm and an underpinning reinforcement stiffness matching algorithm, it achieves automatic identification of sudden local instability of the original foundation and coordinated execution of underpinning and reinforcement. This solves the core problems of phased implementation of underpinning and reinforcement, disconnection of actions at both ends under sudden instability, and stress redistribution imbalance easily leading to structural cracking and irreversible structural damage. First, a single-parameter threshold is used for initial screening to eliminate normal states. Then, settlement, stress, and crack multi-dimensional data are normalized and weighted into a unified risk index. Combined with continuous multi-cycle trend analysis, it accurately classifies primary and advanced instability. This solves the problems of traditional single-parameter independent threshold judgment being easily affected by construction vibration, resulting in misjudgments and omissions, inability to quantify the overall degree of regional instability, and lag in identifying gradual instability trends. This provides a reliable basis for graded linkage response. The stiffness matching algorithm for underpinning and reinforcement establishes a quantitative correspondence between the actions at both ends based on the principle of stiffness coordination. Combined with the timing control logic of reinforcement followed by underpinning, it precisely matches the force and rhythm of the actions at both ends. This solves the problems of relying on human experience in handling sudden instability and the potential for additional deformation and secondary damage due to poor action matching. It effectively curbs the development of instability while minimizing the disturbance to the historically protected building caused by control operations. The hydraulic and mechanical dual-locking structure quickly locks the underpinning force under extreme conditions, and multiple triggering logics ensure reliable locking. This solves the problems of insufficient safety redundancy and the potential for secondary stress fluctuations caused by pullbacks in existing underpinning systems, comprehensively ensuring structural safety and architectural preservation throughout the entire construction cycle. Attached Figure Description

[0042] Figure 1 This is a flowchart illustrating the overall workflow of the method of the present invention;

[0043] Figure 2 This is a flowchart of the instability classification determination process of the present invention;

[0044] Figure 3 This is a flowchart of the hierarchical linkage response of the present invention. Detailed Implementation

[0045] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0046] This embodiment uses the replacement project of a three-story brick-wood mixed structure historical building in a soft soil area as an application scenario. The building is 24m long and 12m wide, with solid brick walls. The protection level is Level II, and the core control requirements are no visible damage to the facade and a crack propagation rate of no more than 0.01mm / h. The construction area consists of miscellaneous fill, silty clay, and silty clay stabilized layers from top to bottom. The local soil is easily softened by construction disturbance.

[0047] like Figure 1 As shown, system deployment and commissioning were completed before construction. The system is divided into four independent control zones along the building's longitudinal direction, each approximately 6 meters wide. Each control zone is a local area for instability detection and linkage control. Each local area is equipped with a linkage unit consisting of sensing points, replacement points, and reinforcement components. Each local area is independently controlled, while data is interconnected across the entire area. After system deployment, joint commissioning was conducted: all sensors were calibrated and zero-point calibrated, and initial reference values ​​were collected; the lifting adjustment unit underwent no-load pressure testing and stroke verification; the safety self-locking module was tested for locking function, simulating hydraulic pressure loss and manual locking commands to verify the locking response; redundancy switching tests were conducted on wired and wireless communication links; and reference tolerance values, weight coefficients, correction coefficients, thresholds at all levels, and zone mapping tables were entered into the central linkage control module. After successful commissioning, the system entered formal operation.

[0048] The multi-source sensing module includes a deformation monitoring unit, a stress monitoring unit, an attitude monitoring unit, and a crack monitoring unit, with each monitoring unit correspondingly deployed at the target stress node. In this embodiment, the target stress node refers to the stress-bearing part where the structural response during the underpinning construction is most indicative of local instability. Specifically, it includes the top surface of the original foundation, column bases, the mid-span and support sections of the underpinning beam, the load-bearing section of the wall, the column body, roof truss nodes, and the ends of existing cracks and areas prone to cracking.

[0049] The deformation monitoring unit uses a high-precision inductive displacement sensor with a range of ±50mm and an accuracy of ±0.01mm. One vertical settlement measuring point is installed every 2m along the top surface of the existing strip foundation, totaling 32 measuring points; eight horizontal bidirectional displacement measuring points are installed at the bases of the four corner columns of the building. During installation, the measuring point locations are ground smooth, and magnetic bases are adhered with epoxy mortar. The sensors are then magnetically fixed to the bases and protected by external metal covers. Settlement benchmarks are set on stable ground 30m outside the construction influence area, and the benchmark values ​​are periodically verified using second-order leveling.

[0050] The stress monitoring unit employs surface-mounted vibrating wire strain gauges on the support component side, with a range of ±1500με and an accuracy of ±1με, deployed at 24 measuring points at the mid-span and support sections of the support beam. On the superstructure side, embedded stress sensors are used, deployed at 16 measuring points at the load-bearing sections of the walls and columns. The strain gauges on the support beam are spot-welded to the steel profile surface. The wall sensors are pre-embedded through drilled holes and backfilled with epoxy mortar. Lead wires are concealed along the mortar joints of the wall, without damaging the exterior facade.

[0051] The attitude monitoring unit uses a dual-axis tilt sensor, which is deployed in layers along the building height direction at the bottom of the wall, the middle of the wall, and the roof truss nodes. It simultaneously captures the attitude changes of the wall in and out of the plane, avoiding the problem that data from a single measuring point cannot reflect the overall tilt trend.

[0052] The crack monitoring unit uses a vibrating wire crack gauge, which is deployed along the crack direction at the ends of existing cracks and at crack-prone areas. The crack gauge is anchored across the crack at both ends to collect crack width and expansion data.

[0053] In terms of networking, each monitoring unit is connected to a zone acquisition node according to local area, and each zone acquisition node is connected to the central linkage control module via an edge gateway. Sampling is triggered by a unified clock, and the clocks of each zone acquisition node are synchronized through network time synchronization to ensure time synchronization of multi-dimensional data in the same local area. Data transmission adopts dual-channel redundancy of RS485 bus wired transmission and LoRa wireless transmission, and automatically switches when either channel is interrupted. Under normal monitoring conditions, sampling is performed once every 10 minutes, and when a primary instability or higher level is determined, sampling is increased to once every 1 minute.

[0054] The replacement execution module includes a replacement bearing unit, a lifting and adjustment unit, and a replacement beam unit.

[0055] The underpinning unit employs statically driven steel pipe piles; in this embodiment, 219mm diameter and 8mm wall thickness steel pipe piles are used. During construction, static pressure pile driving equipment is used to drive the steel pipe piles into the designed depth section by section, with the pile tip penetrating the silty clay layer to a stable depth of at least 2m. Static pressure driving relies on the static pressure provided by the equipment's own weight and counterweight, eliminating hammer vibration and soil displacement impact, thus minimizing construction disturbance to adjacent existing foundations. A pile cap is formed by welding a steel plate to the top of the pile, serving as the installation base for the lifting and adjustment unit.

[0056] The replacement beam unit uses steel replacement beams, which are fitted snugly beneath the existing foundation. During installation, the existing foundation is excavated in sections below the bottom surface. After the steel beams are embedded, micro-expansion grout is injected into the contact surface between the top surface of the steel beams and the bottom surface of the existing foundation. The micro-expansion grout is made by adding an expansion agent to cement-based grout. After curing, its volume expands slightly, which can eliminate gaps at the contact surface and evenly distribute the load of the original foundation to each replacement point through the replacement beams, avoiding local stress concentration that could damage the original foundation.

[0057] The lifting and adjusting unit uses hydraulic jacks equipped with proportional pressure regulating valves and hydraulic pump stations, independently set up for each group of supporting bearing units. The jacks sit on the steel plate of the pile cap foundation, with the lifting end pressed against the bottom surface of the supporting beam. A proportional pressure regulating valve is connected in series on the jack's oil inlet line, and a pressure sensor is installed in the oil line. A displacement sensor is installed at the jack piston. The working principle of graded pressure adjustment is as follows: the central linkage control module calculates the target oil pressure according to the target supporting force, controls the proportional pressure regulating valve to increase the output pressure step by step, with each increase not exceeding 20% ​​of the target value. After each level of pressure stabilization, the pressure and displacement data are read back. After confirming that there are no abnormalities, the next level is executed until the target supporting force is reached, achieving smooth adjustment of the supporting force. Each lifting and adjusting unit is connected to the central linkage control module. The supporting force data is transmitted back throughout the adjustment process. The execution is determined to be successful after the commanded target value is compared with the transmitted measured value, forming a closed-loop verification of command execution. Each support point can be adjusted individually, or multiple points can be linked together to achieve regional load redistribution. When multiple points are linked together, the principle of conservation of total regional load shall be followed.

[0058] The reinforcement execution module includes an embedded reinforcement unit, a constraint adjustment unit, and a directional grouting unit.

[0059] The embedded reinforcement units utilize drilled, inlaid steel rods installed inside the walls and around the columns. During construction, a small drilling rig is used to drill horizontal holes at the mortar joints in the wall, with the hole diameter slightly larger than the steel rod diameter. After cleaning the holes, the steel rods are inserted and pressure-injected with cement-based anchoring grout. Once the grout has solidified, the steel rods are anchored to the wall as a whole. A circumferential arrangement is used around the columns. Both drilling and anchoring are completed inside the wall, leaving only tiny openings on the building facade that match the mortar joints. After repair, there are no visible traces, preserving the building's appearance. The steel rods are exposed at both ends and machined with external threads, serving as the connection points for the constraint adjustment units.

[0060] The constraint adjustment unit employs a mechanical tensioning mechanism, connected in conjunction with the steel bars of the embedded reinforcement unit. It includes a pressure-bearing plate, tensioning nuts, and a force-measuring device. The pressure-bearing plate adheres to the wall surface to distribute localized pressure. The tensioning nuts are screwed onto the external threads at the ends of the steel bars. Tightening the nuts applies preload to the steel bars, creating active constraint as the steel bars on both sides of the wall pull against each other, limiting crack propagation. The force-measuring device uses a pressure sensor ring connected in series at the tensioning end to read the preload in real time and transmit it back to the central linkage control module. The mechanical tensioning mechanism features a simple structure, controllable operation, and good force retention. Even after the power system is disengaged after preload application, the structural reinforcement constraint remains effective, meeting the dual requirements of low disturbance and high reliability for historically protected buildings.

[0061] The directional grouting unit includes foundation grouting pipes arranged in a fan shape towards the softened areas of the foundation and wall grouting pipes arranged along the mortar joints of the walls. The foundation grouting pipes are driven in a radial fan shape from the outside of the building towards the local area, with the pipe ends located in the softened soil layer. Grout is supplied by a grouting pump via flow and pressure monitoring devices, using ultra-fine cement-water glass dual-liquid grout, injected in layers and in quantitative quantities to solidify the softened soil and seal seepage channels. The wall grouting pipes use fine-diameter grouting needles inserted into the wall mortar joints to slowly inject hard lime grout under low pressure. This grout is compatible with the raw materials of the brick mortar joints, penetrating and reinforcing weak points in the wall. The grouting volume is determined quantitatively according to the extent of soil softening and the volume of weak points in the wall. The reinforcement components for each local area are independently controllable, forming a coordinated control system with the corresponding underpinning points.

[0062] The central linkage control module adopts a hardware architecture combining an industrial computer and a programmable logic controller (PLC). It connects to the edge gateways of each zone via a communication bus to receive multi-source monitoring data from the multi-source sensing modules. It connects to the proportional pressure regulating valve of the lifting adjustment unit, the force measuring device of the constraint adjustment unit, and the grouting pump of the directional grouting unit via control cables to issue execution commands. A separate hard-wired safety circuit, independent of conventional communication, connects to a safety self-locking module to ensure the reliability of emergency trigger signal transmission. The module integrates a data processing unit, an instability judgment unit, a command generation unit, a timing control unit, a callback control unit, a storage unit, and a human-machine interface unit. The data processing unit, located at the module input, performs outlier removal, smoothing filtering, and spatial coordinate matching, outputting standardized multi-source monitoring data. The instability determination unit has a built-in local area comprehensive instability index calculation model, performing single-parameter preliminary judgment, local area comprehensive instability index calculation, trend analysis, and level classification. The instruction generation unit has a built-in underpinning and reinforcement stiffness matching calculation model, generating underpinning force adjustment instructions and reinforcement constraint strengthening instructions according to the instability level. The timing control unit manages the action sequence, rate matching, and logical interlocking of both ends. The callback control unit restores normal construction according to the step-by-step callback logic. The storage unit retains the monitoring and handling data of the entire process. The human-computer interaction unit displays the local area comprehensive instability index, level status, and execution progress of each local area, and receives manual locking instructions.

[0063] The safety self-locking module includes a hydraulic locking unit, a mechanical locking unit, and an emergency triggering unit.

[0064] The hydraulic locking unit uses a normally closed hydraulic lock, i.e., a hydraulically controlled one-way valve assembly, connected in series in the inlet and return oil lines of the rodless chamber of the jack in the lifting adjustment unit. During normal operation, the control oil pressure opens the valve core, ensuring unobstructed oil flow; when locking is triggered, the control oil is depressurized, and the valve core returns to its closed position under the action of the spring, locking the oil in the rodless chamber of the jack, momentarily maintaining the lifting pressure and supporting force, and preventing sudden subsidence of the original foundation.

[0065] The mechanical locking unit is a rigid self-locking structure. In this embodiment, a locking nut type structure is adopted: the outer circumference of the jack piston rod is machined with external threads and fitted with a load-bearing locking nut. During the lifting process, the locking nut rotates and rises with the piston rod, always keeping it in contact with the top surface of the jack cylinder. In the event of hydraulic failure, the piston rod load is directly transferred to the cylinder and the top of the pile through the locking nut, forming a rigid support path. It can bear the entire vertical load without relying on the hydraulic system to maintain pressure. As an alternative, a wedge-type self-locking structure can also be adopted, that is, an annular wedge preloaded by a disc spring is set on the outer circumference of the piston rod. When the piston rod tends to sink, the wedge self-locks under the action of friction, transferring the load to the fixed support.

[0066] The emergency triggering unit features multiple triggering logics: abnormal hydraulic pressure is monitored and determined by the oil circuit pressure sensor; the comprehensive instability index of a localized area reaches a critical value, which is output by the instability determination unit; and a manual locking command is issued by the human-machine interface unit or the on-site emergency stop button. All three triggering sources are connected to a hard-wired safety circuit, with the triggering priority being: abnormal hydraulic pressure triggering, comprehensive instability index of a localized area reaching a critical value triggering, and manual locking command triggering. Any trigger simultaneously drives the hydraulic locking unit to move and the mechanical locking unit to its corresponding position. This dual locking mechanism jointly prevents sudden subsidence of the original foundation, providing a safety net for extreme working conditions. Directional grouting operations can continue while the foundation is locked, solidifying the softened soil and restoring its bearing capacity.

[0067] like Figure 1 As shown, after the system is running, the multi-source sensing module continuously collects structural deformation, stress, and crack response data throughout the entire underpinning construction process, obtaining multi-source monitoring data and transmitting it to the central linkage control module. The data processing unit performs the following steps on the multi-source monitoring data in sequence: outlier removal, using an amplitude threshold combined with a three-times-standard-deviation criterion to filter out jump data caused by construction vibration; smoothing filtering, using a moving average filter to eliminate random data fluctuations; and spatial coordinate matching, using a preset mapping table of measuring point numbers, spatial coordinates, and local areas to associate the original foundation deformation data, underpinning force data, and superstructure response data of the same local area one by one, constructing an integrated data mapping relationship to obtain standardized multi-source monitoring data. The fixed monitoring period ΔT is 1 hour, and each incremental parameter is statistically analyzed according to the increment within the fixed monitoring period.

[0068] like Figure 2 As shown, the baseline tolerance value is determined as follows in this embodiment: =0.02mm, converted to a fixed monitoring cycle of 1 hour based on the daily settlement alarm value of 0.5mm / d; =2MPa, determined according to the allowable stress increment control value of the supporting beam steel; =0.01mm, calculated based on the crack propagation rate limit of 0.01mm / h required for landscape protection and a fixed monitoring cycle of 1h. Weighting coefficients are W1 = 0.45, W2 = 0.30, and W3 = 0.25, with a sum of 1. The initial warning value is 0.7, the warning interval is the range where the comprehensive instability index of the local area is greater than or equal to 0.7 and less than 0.9, the warning limit is 0.9, and the critical value is 1.0.

[0069] Zone 2 is considered as the local area in this assessment. Within a fixed monitoring period, the most unfavorable measured value for Zone 2 is: =0.019mm, normalized ratio is 0.95; =1.8MPa, normalized ratio is 0.90; =0.009mm, normalized ratio value is 0.90. In the initial judgment of single parameter thresholds, all three ratios reached the initial warning judgment value of 0.7, and entered the comprehensive judgment stage, calculating the comprehensive instability index of the local area:

[0070] =0.45×0.95+0.30×0.90+0.25×0.90=0.4275+0.27+0.225=0.9225

[0071] Trend analysis shows that the local comprehensive instability index of zone 2 in the first two fixed monitoring cycles was 0.86 and 0.89, respectively, and rose to 0.9225 in this cycle. It has increased in each of the three fixed monitoring cycles and has exceeded the warning limit of 0.9, so it is judged as high-level instability. The judgment result is output and the hierarchical linkage response is initiated.

[0072] like Figure 3 As shown, after being determined to be a high-level instability, the instruction generation unit executes the following process.

[0073] The first step is parameter measurement and command calculation. A trial jacking test was conducted on the jacking point in section 2, applying jacking force increments of 5kN, 10kN, 15kN, and 20kN in stages. A 20kN jacking force increment corresponds to a displacement increment of 0.5mm. The slope of the linear segment of the force-displacement curve was obtained. =40kN / mm; A 10kN test tension was applied to the embedded reinforcing member, and the horizontal deformation at the top of the wall was measured to be 0.083mm. The result was calculated as follows: Approximately 120 kN / mm; based on the measured stress increment and settlement data of the replacement beam, the estimated bearing capacity for soil softening loss in zone 2 is approximately 30 kN, thus determining... =30kN; Zone 2 is a secondary protected brick-and-wood structure, take k=0.7. Substitute into the stiffness matching formula:

[0074] =0.7×(120 / 40)×30=63kN

[0075] The reinforcement components are embedded on both sides of the wall in Zone 2, with a strength of approximately 31.5 kN on each side.

[0076] The second step is to suspend the excavation work in Zone 2 and simultaneously start the directional grouting unit. The foundation fan-shaped grouting and the wall mortar joint grouting are injected quantitatively according to the calculated amount.

[0077] The third step involves the sequential execution of reinforcement followed by replacement. The priority is to drive the constraint adjustment unit to tension at a rate not exceeding 5 kN / min, applying a preload of 63 kN within approximately 13 minutes, which is then verified by the force measuring device. Prior to this, the logic interlock takes effect, and the adjustment amount of the single-stage replacement force at the replacement end must not exceed [a certain value]. 10%, or 3kN. After the structural reinforcement constraints are in place, the interlock is released, and the jacking adjustment unit is driven. =30kN is distributed to three support points in zone 2 according to the distance from the center of instability, namely 12kN, 10kN and 8kN respectively. The sum of the three is equal to 30kN, which satisfies the principle of conservation of total load in the area. Each jack is adjusted at a uniform and gradual speed of no more than 2kN / min, and the support force data is transmitted back for closed-loop verification throughout the process.

[0078] The fourth step involves real-time assessment of emergency conditions during execution, which was not triggered in this case. Subsequently, the structural status was verified. After adjustment, the comprehensive instability index of the local area dropped to 0.81 within two fixed monitoring cycles, falling back into the warning range. Construction was slowed down and observation continued according to the initial instability path. After the grout solidified, the comprehensive instability index of the local area dropped to 0.68, entering the safe range. It remained stable in the safe range for six consecutive fixed monitoring cycles without any upward trend.

[0079] If it is determined to be primary instability, then proceed as follows: Figure 3 Left-side path execution: Slow down the construction pace, slightly strengthen the structural reinforcement constraints of the constraint adjustment unit, fine-tune the support force of the lifting adjustment unit, and then track the changes in the comprehensive instability index of the local area. When falling, maintain observation, and when rising, return to step S2 to re-determine instability.

[0080] An abnormal dewatering event near the foundation pit caused a sudden drop in hydraulic pipeline pressure in Zone 2. The emergency trigger unit was activated with the highest priority due to the hydraulic pressure anomaly: the normally closed hydraulic lock momentarily shut off the oil circuit to maintain the supporting force; when the pressure continued to be lost, the locking nut type mechanical locking unit engaged, and the piston rod load was transferred to the cylinder and pile top through the locking nut, bearing the entire vertical load without relying on the power system, thus preventing sudden settlement of the original foundation; in the locked state, the directional grouting unit continued to grout to solidify and soften the soil. After the fault was eliminated, the comprehensive instability index of the local area returned to the safe range, and the pullback conditions were met, the system was unlocked and restored according to the step-by-step pullback logic.

[0081] like Figure 1As shown, the callback conditions are met: the comprehensive instability index of the local area remains stable within the safe range for six consecutive fixed monitoring cycles without an upward trend, and the foundation bearing capacity is restored after grouting consolidation. The callback control unit then executes a step-by-step callback: first, the 30kN underpinning force adjustment of the underpinning execution module is reduced in five levels, each level decreasing by 20% (6kN). After each level is completed, the system pauses for one fixed monitoring cycle to verify the structural response data. Once stability is confirmed, the next level is executed. After the underpinning force is completely stable, the structural reinforcement constraint strength is weakened in the same step-by-step manner to avoid secondary disturbances caused by sudden constraint release. If the comprehensive instability index of the local area rises back to the warning range during a certain level of verification, the callback is paused and the system returns to the previous level. After the callback is completed, the system resumes normal monitoring and construction, and retains the entire process data for model optimization and project review.

[0082] The above are merely preferred embodiments of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principle of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A method for coordinated control of underpinning and structural reinforcement in historically preserved buildings, characterized in that, Includes the following steps: S1. Data Acquisition: Through multi-source sensing modules deployed at the target stress nodes of the original foundation and superstructure of the historical building, structural deformation, stress and crack response data are collected throughout the entire process of the underpinning construction to obtain multi-source monitoring data, and the multi-source monitoring data is transmitted to the central linkage control module. S2. Instability Determination: The central linkage control module performs comprehensive calculations on the multi-source monitoring data based on the built-in local area comprehensive instability index calculation model to obtain the local area comprehensive instability index, and classifies the instability level of the local area accordingly. S3. Graded linkage control: According to the instability level, the central linkage control module generates underpinning force adjustment instructions and reinforcement constraint strengthening instructions based on the built-in underpinning and reinforcement stiffness matching calculation model. It drives the underpinning execution module set in the stable soil layer below the original foundation to adjust the underpinning force distribution at each underpinning point, and drives the reinforcement execution module set in the upper wall and column to adjust the structural reinforcement constraint strength, so as to realize the dual-end linkage execution of underpinning end unloading and reinforcement end crack limiting. S4. Status Verification and Step-by-Step Recall: After the control is executed, the structural status is continuously verified. If the structural status is not stable, return to step S1 for continuous monitoring and control. When the comprehensive instability index of the local area is stable in the safe range for several consecutive fixed monitoring cycles and there is no upward trend, the step-by-step callback is executed in the order of first replacing and then reinforcing, step-by-step reduction, and segment-by-segment verification to restore normal construction.

2. The method for coordinated control of historical building underpinning and structural reinforcement according to claim 1, characterized in that, After step S1 and before step S2, the central linkage control module sequentially performs outlier removal, smoothing filtering, and spatial coordinate matching on the multi-source monitoring data: outlier removal filters out jump data caused by construction vibration, smoothing filtering eliminates random data fluctuations, and spatial coordinate matching associates the original foundation deformation data, underpinning force data, and superstructure response data of the same local area one by one to construct an integrated data mapping relationship and obtain standardized multi-source monitoring data; in step S2, the standardized multi-source monitoring data is comprehensively calculated.

3. The method for coordinated control of historical building underpinning and structural reinforcement according to claim 1, characterized in that, The local regional comprehensive instability index calculation model adopts multi-parameter normalized weighted calculation, and the calculation formula is as follows: ； In the formula: This refers to the comprehensive instability index of the local area. The measured value of the settlement of the original foundation within the fixed monitoring period; The baseline allowable value for basic settlement; The measured value of the stress increment of the supporting beam within the fixed monitoring period; This is the allowable value for stress increment; The measured value of crack propagation within the fixed monitoring period; W1 represents the baseline allowable value for crack propagation; W2 and W3 are the weighting coefficients for the three parameters: settlement, stress, and crack, respectively.

4. The method for coordinated control of historical building underpinning and structural reinforcement according to claim 3, characterized in that, The instability levels include primary instability and advanced instability. In step S2, the ratio of the measured value of each single parameter to the corresponding benchmark allowable value is calculated, and each ratio is compared with the initial warning value. When each ratio is lower than the initial warning value, normal monitoring is maintained. When any ratio reaches the initial warning value, the local area comprehensive instability index is calculated, and trend analysis is performed on the local area comprehensive instability index for multiple consecutive fixed monitoring periods. When the local area comprehensive instability index is in the warning range and the change is maintained within the preset range, it is determined to be primary instability. When the local area comprehensive instability index exceeds the warning limit or shows a continuous upward trend, it is determined to be advanced instability.

5. The method for coordinated control of historical building underpinning and structural reinforcement according to claim 4, characterized in that, In step S3, if the instability is determined to be primary, the construction pace is slowed down, the reinforcement execution module is driven to strengthen the structural reinforcement constraints, and the underpinning execution module is driven to fine-tune the underpinning force. Then, the change of the comprehensive instability index of the local area is tracked. When the comprehensive instability index of the local area falls, observation is maintained. When the comprehensive instability index of the local area rises, the process returns to step S2 to re-determine the instability. If the instability is determined to be advanced, the construction work is suspended, the reinforcement execution module is driven to initiate directional grouting reinforcement of the foundation and walls of the local area and strengthen the structural reinforcement constraints, and the multiple underpinning points of the underpinning execution module are driven to transfer the load in a coordinated manner.

6. The method for coordinated control of historical building underpinning and structural reinforcement according to claim 1, characterized in that, The stiffness matching calculation model for the underpinning reinforcement is established based on the principles of stiffness equivalence and deformation compatibility, and the calculation formula is as follows: ； In the formula: Adjust the preload increment of the upper reinforcing component of the reinforcement execution module; The adjustment amount of the supporting force at the supporting points in the local area; This refers to the equivalent deformation stiffness of the superstructure in the local area. The equivalent vertical stiffness of the foundation underpinning system corresponding to the local area; For historical building protection correction factors; The The bearing capacity is determined based on the soil softening loss in the local area; when multiple underpinning points in the local area are adjusted in a coordinated manner, the sum of the underpinning force adjustments at each underpinning point is equal to... Furthermore, the adjustment amount of the replacement force at each replacement point is distributed according to the distance from the center of instability.

7. The method for coordinated control of historical building underpinning and structural reinforcement according to claim 1, characterized in that, When executing the control command in step S3, the timing control logic of strengthening before replacement is followed: the strengthening execution module is driven first to strengthen the structural reinforcement constraints, and after the structural reinforcement constraints reach the target value, the replacement execution module is driven to adjust the replacement force; both the replacement force adjustment and the strengthening of the structural reinforcement constraints are executed in a uniform and gradual manner; and a logic interlock mechanism is set up so that the replacement end is prohibited from performing large-scale replacement force adjustments when the structural reinforcement constraints are not adjusted in place.

8. The method for coordinated control of historical building underpinning and structural reinforcement according to claim 3, characterized in that, During the execution of steps S3 and S4, emergency conditions are assessed in real time. When the hydraulic pressure of the replacement execution module is abnormal, the comprehensive instability index of the local area reaches a critical value, or a manual locking command is received, the safety self-locking module linked with the replacement execution module is triggered to lock the replacement force of the replacement execution module. The triggering priority from high to low is: hydraulic pressure abnormality trigger, comprehensive instability index of the local area reaching a critical value trigger, and manual locking command trigger. When locking is triggered, the hydraulic circuit of the replacement execution module is locked first to maintain the replacement force. When the hydraulic system fails, the rigid self-locking structure engages to lock and bear the vertical load.

9. A linkage control system for historical building underpinning and structural reinforcement, used to implement the linkage control method for historical building underpinning and structural reinforcement as described in any one of claims 1 to 8, characterized in that, It includes a multi-source sensing module, a replacement execution module, a reinforced execution module, a central linkage control module, and a safety self-locking module; The multi-source sensing module is deployed at the target stress nodes of the original foundation and superstructure of the historical building to collect structural deformation, stress and crack response data throughout the entire underpinning construction process, and obtain multi-source monitoring data. The underpinning execution module is set in the stable soil layer below the original foundation, and is used to bear the vertical load of the historical building and dynamically adjust the underpinning force distribution at the underpinning point. The reinforcement execution module is deployed at the upper wall and column locations to apply structural reinforcement constraints and dynamically adjust the strength of the structural reinforcement constraints. The central linkage control module is connected to the multi-source sensing module, the underpinning execution module, the reinforcement execution module, and the safety self-locking module. It has a built-in local area comprehensive instability index calculation model and underpinning and reinforcement stiffness matching calculation model. It is used to comprehensively calculate the multi-source monitoring data, obtain the local area comprehensive instability index and classify the instability level of the local area. Based on the stiffness matching principle, it generates underpinning force adjustment command and reinforcement constraint strengthening command, driving the underpinning execution module and the reinforcement execution module to execute in linkage. The safety self-locking module is linked with the replacement execution module and is used to lock the replacement force of the replacement execution module in emergency situations.

10. The linkage control system for historical building underpinning and structural reinforcement according to claim 9, characterized in that, The safety self-locking module includes a hydraulic locking unit, a mechanical locking unit, and an emergency triggering unit. The hydraulic locking unit is a normally closed hydraulic lock connected to the hydraulic circuit of the replacement execution module. After triggering, it locks the oil circuit to maintain the replacement force. The mechanical locking unit is a rigid self-locking structure, which is configured in conjunction with the lifting adjustment unit of the replacement execution module to engage and lock in case of hydraulic failure and to bear vertical loads. The emergency triggering unit has multiple triggering logics. Locking can be triggered by abnormal hydraulic pressure, the comprehensive instability index of the local area reaching a critical value, and a manual locking command. The triggering priority is from high to low as follows: abnormal hydraulic pressure triggering, comprehensive instability index of the local area reaching a critical value triggering, and manual locking command triggering.

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