Foundation pit deformation control method and system

Abstract

The invention provides a foundation pit deformation control method and system, and relates to the technical field of foundation pit supporting engineering, and the method comprises the steps that a servo station accumulatively receives strain data returned by a strain gauge, and generates time sequence strain data; sTL time sequence decomposition of foundation pit deformation characteristics is carried out, and deformation trend item characteristics, deformation period item characteristics and deformation residual item characteristics are obtained; performing foundation pit time sequence deformation prediction, and outputting foundation pit strain prediction data; deducing a deformation intervention demand, and outputting pre-compensation time sequence pressure; and time sequence adjustment of hydraulic oil output pressure is carried out to drive an oil jack to carry out foundation pit predictive deformation compensation. The technical problems that traditional foundation pit supporting depends on the preset prestress of a concrete supporting beam and cannot be dynamically adjusted according to deformation generated in the actual excavation process of a foundation pit, so that deformation of the foundation pit cannot be effectively controlled, and the risk that the foundation pit is unstable is increased are solved. The technical effect of improving the real-time performance and accuracy of foundation pit deformation compensation is achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of foundation pit support engineering, in particular to a foundation pit deformation control method and system. BACKGROUND

[0002] In foundation pit engineering, the design and control of the support system are crucial, especially under deep foundation pits or complex geological conditions. Traditional foundation pit support systems usually adopt a passive force mode, relying on the preset prestress of concrete support for support. However, this method has the problem of being unable to dynamically adjust with excavation. As the foundation pit construction proceeds, the excavation of the surrounding soil will cause the foundation pit to deform, and the fixed prestress support cannot effectively respond to these dynamic deformations, leading to uncontrollability of the deformation of the enclosure structure, which poses a risk to the safety of construction and the stability of the foundation pit. In addition, existing servo support is mostly a steel support system, which has a certain adjustability in some cases, but the steel support is usually insufficient in stiffness and is prone to instability, and cannot withstand excessive external force or deformation, which limits the application of steel support in foundation pit deformation control. SUMMARY

[0003] The present application provides a foundation pit deformation control method and system to solve the technical problem that traditional foundation pit support relies on the preset prestress of concrete support beams and cannot be dynamically adjusted according to the deformation that occurs during the actual excavation process of the foundation pit, resulting in ineffective control of foundation pit deformation and increasing the risk of instability of the foundation pit.

[0004] In view of the above problems, the present application provides a foundation pit deformation control method and system.

[0005] In a first aspect of the present application, a foundation pit deformation control method is provided, which comprises: The servo station accumulates the strain data returned by the strain gauge to generate time series strain data, performs STL time series decomposition on the time series strain data to obtain deformation trend item features, deformation period item features and deformation residual item features, performs foundation pit time series deformation prediction based on the deformation trend item features, deformation period item features and deformation residual item features, outputs foundation pit strain prediction data, derives deformation intervention requirements based on the foundation pit strain prediction data, and outputs pre-compensation time series pressure. The oil pressure station receives and adjusts the time series of the output pressure of the hydraulic oil according to the pre-compensation time series pressure to drive the oil pressure jack to perform predictive deformation compensation of the foundation pit.

[0006] In a second aspect of the present application, a foundation pit deformation control system is provided, which comprises: The foundation pit deformation support system comprises a concrete support beam and an oil pressure jack, a piston end of the oil pressure jack is pressed against an inner side enclosing purlin of the concrete support beam, and a cylinder end of the oil pressure jack is pressed against an outer side enclosing purlin of the concrete support beam; a strain gauge is arranged inside the concrete support beam; a servo station is connected with the strain gauge through a first data lead wire, and the servo station is fixedly installed on the ground around the foundation pit; an oil pressure station comprises a hydraulic power unit body and a hydraulic oil pipe, the oil pressure station is connected with the oil pressure jack through the hydraulic oil pipe, and the oil pressure station is connected with the servo station through a second data lead wire, and the servo station is fixedly installed on the ground around the foundation pit; wherein the servo station receives real-time strain data of the strain gauge through the first data lead wire to perform stress analysis on the supporting structure, outputs a compensation pressure value, and sends the compensation pressure value to the oil pressure station through the second data lead wire to control the oil pressure station to dynamically adjust the hydraulic oil output pressure, drive the oil pressure jack to perform hydraulic compensation for millimeter-level deformation of the foundation pit.

[0007] One or more technical solutions provided in the application have at least the following technical effects or advantages: The servo station accumulates strain data received from strain gauges and generates time-series strain data, enabling real-time monitoring of the foundation pit's deformation and providing continuous data input for subsequent analysis. The accumulation of strain data ensures continuous monitoring of foundation pit deformation, preventing the loss of critical deformation data and providing a data foundation for accurate prediction. STL time-series decomposition of the time-series strain data extracts deformation trend, periodic, and residual features from the complex data. This process isolates different deformation modes, allowing for more detailed identification of different sources of foundation pit deformation, thus enabling more targeted prediction and compensation. Based on these features, the time-series deformation of the foundation pit is predicted, and the predicted strain data is output. This prediction allows for the early identification of potential deformation trends and the prediction of future deformation, transforming foundation pit deformation control from a reactive approach into a proactive one. The prediction and real-time adjustment greatly improve the safety and efficiency of the construction process. Based on the predicted strain data of the foundation pit, the deformation intervention requirements are derived, and the pre-compensation time-series pressure is output. It can calculate the compensation pressure value required at certain future time points according to the predicted deformation data, so as to carry out precise intervention and help to achieve precise control of deformation compensation, avoiding the lag and inaccuracy of traditional foundation pit deformation compensation methods. The hydraulic station adjusts the hydraulic oil output pressure according to the pre-compensation time-series pressure to drive the hydraulic jack for predictive deformation compensation of the foundation pit. This refined control allows the foundation pit deformation compensation to be adjusted in real time according to the predicted data, avoiding the shortcomings of previous compensation by static pressure. By dynamically adjusting the hydraulic oil output according to the time-series pressure requirements, the action of the hydraulic jack can be controlled more precisely, improving the real-time performance and accuracy of foundation pit deformation compensation, avoiding the risk of excessive deformation or insufficient compensation, and ensuring that the foundation pit always remains in a stable and safe state. Attached Figure Description

[0008] Figure 1 A schematic diagram of the foundation pit deformation control method provided in this application.

[0009] Figure 2 A schematic diagram of the STL time sequence decomposition process in the foundation pit deformation control method provided in this application.

[0010] Figure 3 A schematic diagram of the structure of the foundation pit deformation control system provided in this application.

[0011] Explanation of reference numerals in the attached drawings: 1. Concrete support beam; 2. Hydraulic jack; 3. Strain gauge; 4. Servo station; 5. First data cable; 6. Hydraulic station; 7. Hydraulic oil pipe; 8. Second data cable; 9. Anti-fall steel beam; 10. Load-bearing steel plate. Detailed Implementation

[0012] The application provides a foundation pit deformation control method and system, which aims to solve the technical problem that the preset prestress of the traditional foundation pit support relies on the concrete support beam, cannot be dynamically adjusted according to the deformation occurring in the actual excavation process of the foundation pit, and leads to that the deformation of the foundation pit cannot be effectively controlled, and the risk of instability of the foundation pit is increased.

[0013] Hereinafter, the technical solutions in the application will be described clearly and completely with reference to the drawings. Obviously, the described embodiments are only a part of the embodiments of the application, rather than all the embodiments of the application. It should be understood that the application is not limited by the example embodiments described herein. Based on the embodiments of the application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of protection of the application. In addition, it should be noted that, for the convenience of description, only the parts related to the application are shown in the drawings, not all.

[0014] Embodiment one, as shown in the application, a foundation pit deformation control method is provided, the method comprises: Figure 1 A100: The servo station accumulates the strain data returned by the strain gauge to generate time sequence strain data.

[0015] The servo station receives the strain data returned by the strain gauge, and the strain gauge monitors the strain, i.e. the deformation, of different parts of the foundation pit. The servo station accumulates the received strain data in chronological order to construct a time sequence of strain data, i.e. time sequence strain data, wherein each data point represents the strain condition of the foundation pit at a certain time stamp. The time sequence strain data records the deformation change process of the foundation pit, which is convenient for further analyzing the deformation characteristics of the foundation pit.

[0016] A200: STL time sequence decomposition of the foundation pit deformation characteristics is performed on the time sequence strain data to obtain deformation trend item features, deformation period item features and deformation residual item features.

[0017] ​The STL time series decomposition method is a method for extracting time characteristics from time series data. Through STL time series decomposition, time series strain data is decomposed into three parts. The deformation trend item characteristic represents the long-term change trend of the foundation deformation. The cumulative deformation trend of the foundation is extracted by applying local weighted regression smoothing and other methods to the time series strain data. The deformation period item characteristic represents the periodic change characteristic and is related to environmental changes (such as temperature changes) and construction disturbances and other factors. This item captures the periodic fluctuations of the foundation deformation. The deformation residual item characteristic represents the part of the time series strain data that cannot be explained by the trend item and the period item and is caused by random disturbances or unpredictable factors (such as sudden construction disturbances). In the STL time series decomposition process, in combination with environmental temperature data and construction disturbance data, Fourier spectrum analysis and other techniques are used to capture the periodic fluctuations related to temperature changes, and sliding window and other methods are used to evaluate the random fluctuations caused by construction disturbances. After STL time series decomposition, the above deformation trend item characteristic, deformation period item characteristic and deformation residual item characteristic are obtained.

[0018] A300: Based on the deformation trend item characteristic, deformation period item characteristic and deformation residual item characteristic, a foundation time series deformation prediction is performed, and foundation strain prediction data is output.

[0019] Based on historical data, a sub-item prediction model is constructed, including a trend prediction sub-model, a period prediction sub-model and a residual prediction sub-model. The trend prediction sub-model predicts the cumulative deformation of the foundation based on the deformation trend item characteristic. It predicts the future deformation trend through historical trend data. The period prediction sub-model predicts the deformation of the foundation under different temperature conditions based on the deformation period item characteristic. Through modeling of the periodic deformation data, the future possible periodic deformation is predicted. The residual prediction sub-model predicts the disturbance fluctuations of the foundation based on the deformation residual item characteristic. Through analysis of historical disturbance data, the future possible random fluctuations are predicted. Through linear superposition, the prediction results of the above sub-models are combined, that is, the cumulative deformation of the foundation, the deformation caused by temperature and the random fluctuation caused by disturbance are added to obtain the final foundation strain prediction data. The foundation strain prediction data contains the future strain change trend of the foundation.

[0020] A400: Based on the foundation strain prediction data, a deformation intervention requirement derivation is performed, and a pre-compensation time series pressure is output.

[0021] Based on the foundation pit strain prediction data, the future deformation of the foundation pit is analyzed to determine whether the predicted strain exceeds the safety threshold. The goal is to identify the time point that needs intervention and to derive the deformation compensation requirement at the corresponding time point. According to the derived deformation compensation requirement, the corresponding compensation pressure value is calculated. This compensation pressure value is derived based on the predicted strain, trend and intervention requirement, and represents the hydraulic pressure that should be applied at different times to compensate for the deformation of the foundation pit. The time point that needs intervention and the corresponding compensation pressure value are arranged in time sequence to form a pre-compensation time sequence pressure, which is a pressure curve synchronized with time, indicating how the oil pressure station adjusts the pressure to compensate for the predicted deformation of the foundation pit.

[0022] A500: The oil pressure station receives and adjusts the time sequence of the output pressure of the hydraulic oil according to the pre-compensation time sequence pressure to drive the hydraulic jack to compensate for the predicted deformation of the foundation pit.

[0023] The oil pressure station receives the pre-compensation time sequence pressure and adjusts the output pressure of the hydraulic oil according to the pre-compensation time sequence pressure. By adjusting the oil pressure output, the action of the hydraulic jack is controlled, which is used to actually compensate for the deformation of the foundation pit and ensure that the foundation pit does not deform excessively. During this process, the hydraulic jack controls the deformation process of the foundation pit by providing corresponding force. The adjustment process of the output pressure is precise to ensure that the oil pressure output matches the predicted compensation pressure value. For example, if it is predicted that the foundation pit will have a larger deformation at a certain time, the oil pressure station will output a higher hydraulic pressure to compensate for this deformation. By adjusting the oil pressure station to actually drive the hydraulic jack, the predicted deformation compensation of the foundation pit is achieved, ensuring that the deformation of the foundation pit is always within a controllable range.

[0024] Further, as shown in Figure 2 The method comprises: A210: Tracking the cumulative deformation rate of the concrete support beam based on the time sequence strain data, and outputting the deformation trend feature.

[0025] A220: Synchronously retrieving time sequence environmental temperature data and time sequence construction disturbance data according to the start and end timestamps of the time sequence strain data.

[0026] A230: Aligning the time sequence environmental temperature data and the time sequence strain data, and capturing temperature-induced strain periodic fluctuations through Fourier spectrum analysis to obtain the deformation period feature.

[0027] A240: Aligning the time sequence construction disturbance data and the time sequence strain data, and calculating the predicted random fluctuation intensity through sliding window standard deviation to output the deformation residual feature.

[0028] Concrete support beams are common support structures in foundation pit engineering. They are used to support the soil around the foundation pit and prevent excessive settlement or tilting. During construction, concrete support beams will deform over time. The cumulative deformation rate refers to the amount of deformation that occurs in the concrete support beam over a period of time. This cumulative deformation rate is not only related to the physical properties of the concrete support beam itself, but also affected by external factors such as construction loads and geological conditions.

[0029] When tracking and analyzing time-series strain data, special attention is paid to the cumulative deformation rate of the concrete support beams. This process calculates the deformation rate at each time point and accumulates these data to obtain an overall deformation trend. The output deformation trend term refers to the overall deformation trend of the foundation pit over a period of time, particularly the deformation of the concrete support beams. By tracking these deformation rates, the long-term trend of the concrete support beam deformation can be identified; for example, the concrete support beams may gradually sink or undergo other forms of deformation over time.

[0030] Time-series strain data has a clear timestamp, indicating the exact time of collection for each data point. By extracting the start and end timestamps of the time-series strain data, a specific time period can be determined, which can be used to retrieve other relevant data for synchronous comparative analysis, including retrieving time-series environmental temperature data and time-series construction disturbance data, to identify the specific impact of temperature changes and construction disturbances on the deformation of the foundation pit.

[0031] Among them, ambient temperature has a significant impact on the deformation of the foundation pit, especially in materials such as concrete and steel structures. Temperature changes can cause expansion or contraction, which in turn affects the deformation of the foundation pit. In this process, the ambient temperature data of the time series is retrieved synchronously according to the start and end timestamps of the time series strain data. During construction, especially in other construction activities around the foundation pit, some disturbances will be generated, such as mechanical vibration and changes in construction load. These disturbances will affect the deformation of the foundation pit. Therefore, the construction disturbance data of the time series is retrieved synchronously according to the start and end timestamps of the time series strain data.

[0032] By aligning time-series strain data and time-series environmental temperature data, which are monitoring data on foundation pit deformation and record temperature changes related to the foundation pit environment, time-series alignment ensures that the direct impact of temperature changes on foundation pit deformation can be compared within the same time period.

[0033] Fourier spectrum analysis is a signal analysis method that can convert signals in the time domain into frequency domain signals, revealing the periodic components in the signals. In the analysis of foundation pit deformation, temperature changes are usually periodic, such as daily temperature differences and seasonal changes. These temperature fluctuations can cause the expansion or contraction of foundation pit materials, leading to foundation pit deformation. Through Fourier spectrum analysis, the frequency components of the periodic fluctuations caused by temperature are identified. Specifically, the periodic fluctuations in time-series environmental temperature data are converted into frequency domain data through Fourier transform, revealing how temperature changes affect the periodic deformation of the foundation pit. Through Fourier spectrum analysis, the periodic components obtained are used as deformation period feature, which represents the periodic deformation pattern caused by temperature changes and can reveal the strain fluctuation period of the foundation pit under different environmental temperature conditions.

[0034] Similarly, time-series strain data and time-series construction disturbance data are aligned to analyze the impact of disturbances occurring during construction on foundation pit deformation, and to identify the random effects of unforeseen factors on foundation pit deformation during construction.

[0035] Sliding window standard deviation is a method for time series analysis. By defining a time window, the standard deviation of the data within the time window is calculated, reflecting the degree of data fluctuation. In this step, sliding window standard deviation is used for time-series strain data and time-series construction disturbance data to calculate the fluctuation intensity of strain within each time window. The relationship between construction disturbance data and strain data within each time window can reveal the impact of construction disturbance on foundation pit deformation. The standard deviation calculation result is used to quantify the random fluctuation intensity, i.e. the degree of influence of unpredictable disturbances during construction on foundation pit deformation. By calculating the sliding window standard deviation, the deformation residual feature is extracted, which represents the fluctuations in foundation pit deformation caused by construction disturbances. The deformation residual feature is different from the periodic deformation feature, as it represents the random fluctuation component that cannot be explained by the trend and period components. This feature is used to identify and predict irregular deformation during construction.

[0036] Further, based on the deformation trend feature, deformation period feature and deformation residual feature, the method for predicting the time-series deformation of the foundation pit is performed to output foundation pit strain prediction data, the method comprising: A310: constructing a sub-item prediction model based on historical data, wherein the sub-item prediction model includes a trend prediction sub-model, a period prediction sub-model and a residual prediction sub-model connected in parallel.

[0037] A320: loading the deformation trend feature into the trend prediction sub-model to predict the cumulative deformation of the foundation pit, and outputting the cumulative deformation.

[0038] A330: Load the deformation periodicity feature into the periodic prediction sub-model to predict the temperature deformation of the foundation pit and output the temperature deformation amount.

[0039] A340: Load the features of the deformed residual term into the residual prediction sub-model to predict the range of disturbance fluctuations and output the random disturbance amount.

[0040] A350: The cumulative deformation, temperature deformation, and random disturbance are linearly superimposed to generate the foundation pit strain prediction data.

[0041] A component-based prediction model is constructed using historical data, which includes actual records of past foundation pit deformation, such as historical deformation data, historical ambient temperature data, and historical construction disturbance data. This data indicates the influencing factors of foundation pit deformation. The component-based prediction model is an integrated model, comprising parallel trend prediction sub-models, periodic prediction sub-models, and residual prediction sub-models. These three sub-models are parallel, meaning they independently predict different aspects of foundation pit deformation. The prediction results are then combined to obtain a more comprehensive deformation prediction.

[0042] The trend prediction sub-model is responsible for predicting the cumulative deformation trend of the foundation pit. By analyzing historical deformation data, this trend prediction sub-model can predict the overall deformation trend of the foundation pit in the future. The periodic prediction sub-model is responsible for predicting the deformation caused by the ambient temperature of the foundation pit. By analyzing the relationship between temperature and deformation in historical data, this model can predict the impact of future temperature changes on the deformation of the foundation pit. The residual prediction sub-model is responsible for predicting random fluctuations caused by factors such as construction disturbances. This is based on the part of historical data that cannot be explained by trend and periodic terms. By analyzing disturbance data, it predicts future random fluctuations.

[0043] The extracted deformation trend features are input into the trend prediction sub-model. These features represent the long-term development trend of the foundation pit deformation, helping the trend prediction sub-model to identify and understand the long-term trend of foundation pit deformation, such as settlement and tilting. The trend prediction sub-model uses these features to predict the cumulative deformation of the foundation pit. By learning the trend changes in historical data, it predicts the future cumulative deformation of the foundation pit. The cumulative deformation is the long-term change in foundation pit deformation, such as the total settlement of the foundation pit, which reflects the future deformation trend of the foundation pit over a long period of time.

[0044] The extracted deformation period term feature is input into the period prediction sub-model. The deformation period term feature represents the deformation period of the foundation pit related to external periodic factors such as temperature, helping the period prediction sub-model to capture how temperature changes affect the expansion or contraction of foundation pit materials, thereby affecting the periodic deformation of the foundation pit. The period prediction sub-model uses the deformation period term feature to predict the deformation of the foundation pit caused by temperature changes. By analyzing the relationship between temperature and deformation in historical data, the impact of future temperature changes on the foundation pit is predicted, such as how the foundation pit expands when the temperature rises and how it contracts when the temperature drops. The final output is the temperature deformation, which is the amount of deformation of the foundation pit caused by temperature changes.

[0045] The extracted deformation residual term feature is input into the residual prediction sub-model. The deformation residual term feature represents random fluctuation components that cannot be explained by the trend term and the period term. The residual prediction sub-model uses the deformation residual term feature to predict the disturbance intensity or fluctuation range of the foundation pit caused by construction disturbance or other random factors. After prediction, the output is the random disturbance, which is the intensity of the random deformation fluctuation that the foundation pit may experience in the future. The random disturbance is usually fluctuating and closely related to time, construction progress, or environmental changes.

[0046] The output cumulative deformation, temperature deformation, and random disturbance are linearly superimposed, which means adding the three deformation amounts together to get a total foundation pit deformation prediction, which is the foundation pit strain prediction data, i.e. the overall deformation prediction data of the foundation pit under the combined action of multiple factors in the future. This foundation pit strain prediction data integrates long-term deformation trend, temperature-induced periodic fluctuation, and construction disturbance-induced random fluctuation, providing comprehensive information for the prediction of foundation pit deformation.

[0047] Further, the method further comprises: A610: The servo station receives real-time strain data returned by the strain gauge through the first data wire.

[0048] A620: The real-time strain data is subjected to security verification. If the real-time strain data exceeds the preset security threshold, after calculating the real-time strain increment of the real-time strain data, deformation compensation demand calculation is performed based on the real-time strain increment, and a compensation pressure value is output.

[0049] A630: The servo station sends the compensation pressure value to the oil pressure station through the second data wire.

[0050] A640: The oil pressure station receives and adjusts the hydraulic oil output pressure according to the compensation pressure value, and drives the oil pressure jack to perform low-latency hydraulic compensation of the foundation pit millimeter-level deformation.

[0051] The first data wire is used to transmit real-time strain data measured by the strain gauge from the strain gauge to the servo station, reducing the delay and error in the data transmission process. The servo station is connected to the strain gauge through the first data wire and receives the real-time strain data transmitted back by the strain gauge, which reflects the real-time deformation of the foundation pit at different positions.

[0052] The received real-time strain data is subjected to security verification, which is to determine whether the current deformation of the foundation pit is within the set safety range. The preset safety threshold is a pre-set strain limit value, which represents the maximum deformation that the foundation pit can withstand under normal construction conditions. If the real-time strain data exceeds this preset safety threshold, it indicates that the foundation pit has undergone excessive deformation or has safety hazards, and deformation compensation is needed to avoid structural damage or safety accidents.

[0053] In this case, the real-time strain increment is calculated, which refers to the deformation of the foundation pit relative to the historical strain record of the current real-time strain data, reflecting the recent deformation pattern or sudden events (such as construction disturbance, soil settlement, etc.) of the foundation pit. Based on the calculated real-time strain increment, the deformation compensation demand calculation is performed, which combines the size of the real-time strain increment, the position of the deformation, and the pressure required for compensation, to obtain the compensation pressure value. This compensation pressure value represents the hydraulic pressure that the oil pressure station needs to apply to compensate for the current deformation of the foundation pit.

[0054] The second data wire is used to transmit the compensation pressure value calculated by the servo station to the oil pressure station, so that the oil pressure station can receive the correct compensation requirements and reduce the delay and error in the transmission process. The servo station sends the calculated compensation pressure value to the oil pressure station through the second data wire to respond to the deformation of the foundation pit in real time.

[0055] After receiving the compensation pressure value from the servo station, the oil pressure station starts to adjust its hydraulic oil output pressure, which directly affects the action of the oil pressure jack. The hydraulic oil output pressure is accurately matched with the compensation pressure value to ensure that the deformation of the foundation pit is properly compensated.

[0056] The oil pressure jack is the key device for performing deformation compensation, which pushes or pulls the support structure of the foundation pit through the pressure of hydraulic oil to restore the designed shape of the foundation pit. The action of the oil pressure jack can compensate for millimeter-level deformation of the foundation pit with high precision. In the deformation compensation process, low latency means that compensation is performed in real time. Any delay may lead to worsening of the deformation of the foundation pit and increase the risk of construction. The oil pressure station realizes low-latency hydraulic compensation by quickly responding to the compensation pressure value, which means that the oil pressure station can quickly adjust the hydraulic system to drive the oil pressure jack for deformation compensation of the foundation pit in real time, ensuring the timeliness and accuracy of deformation compensation.

[0057] Further, after calculating the real-time strain increment of the real-time strain data, deformation compensation demand calculation is performed based on the real-time strain increment, and a compensation pressure value is output, the method comprising: A621: According to the collection timestamp of the real-time strain data, a real-time construction stage label is matched in a foundation pit construction log.

[0058] A622: Taking the collection timestamp of the real-time strain data as a starting point, historical strain record backtracking is performed to obtain a short-term strain data stream.

[0059] A623: Increment feature extraction is performed on the real-time strain data based on the short-term strain data stream to obtain the real-time strain increment, wherein the real-time strain increment includes an increment amplitude, an increment acceleration, and a threshold value time window.

[0060] A624: According to the real-time construction stage label, a special compensation model is called.

[0061] A625: The real-time strain increment is input into the special compensation model to perform deformation compensation demand calculation, and the compensation pressure value is output.

[0062] The collection timestamp of the real-time strain data indicates the specific collection time of the data point. The foundation pit construction log is a file recording key activities and stages in the construction process of the foundation pit, and includes information such as the time, construction activities, possible environmental changes, and construction progress of each construction stage. By matching the collection timestamp of the real-time strain data with the real-time construction stage label corresponding to the collection timestamp in the foundation pit construction log, the real-time construction stage label indicates which stage the foundation pit is in at that time, such as excavation, support installation, backfilling, etc. Different stages of construction activities will have different types of effects on the foundation pit.

[0063] Taking the collection timestamp of the real-time strain data as a starting point, the historical strain record is backtracked. The historical strain record contains all strain data of the foundation pit before, and the backtracking process includes calling data several hours or days before the collection timestamp, depending on the monitoring period of the foundation pit deformation and the collection frequency of the strain data. According to the backtracking result, a short-term strain data stream is obtained, which represents the deformation of the foundation pit in the past short time from the collection timestamp, and is used for comparative analysis of the strain increment under the current state of the foundation pit.

[0064] The real-time strain data is compared with the short-term strain data stream to extract the increment feature, which refers to the change amount of the deformation of the foundation pit in the past short time, especially the change compared with the previous strain data. By comparing the short-term strain data stream and the real-time strain data, the deformation increment is calculated.

[0065] The increment amplitude represents the change amount of the foundation pit deformation, specifically, the change amplitude of the real-time strain data relative to the short-term strain data flow, the larger the increment amplitude, the more significant the deformation of the foundation pit; the increment acceleration refers to the change of the deformation rate of the foundation pit, that is, the increment change speed of the deformation in a unit time, the increment acceleration helps to identify the sharp change in the deformation process, which is usually caused by sudden disturbance or uneven settlement; the threshold time window represents the time window in which the strain increment exceeds the preset safety threshold, in some cases, the strain increment of the foundation pit will exceed a certain safety limit, at this time, the time period is recorded, the threshold time window indicates which deformation changes exceed the safety range and needs to be intervened in time. Based on the above increment feature extraction, the real-time strain increment is obtained, including the amplitude, rate and duration of the deformation, which provides a key basis for the subsequent deformation compensation demand calculation.

[0066] According to the real-time construction stage label, the corresponding special compensation model is called, different construction stages will lead to different deformation characteristics, therefore, the appropriate compensation model needs to be selected according to the construction stage, for example, in the support beam installation stage, the deformation of the foundation pit may be caused by the change of the support beam load, while in the backfilling stage, it may be the deformation caused by soil settlement or structure consolidation, therefore, different compensation strategies are needed for different stages, and the corresponding compensation model is called according to the label of the construction stage. The special compensation model is designed for different construction stages and is used to calculate the compensation demand of the foundation pit deformation.

[0067] The calculated real-time strain increment is input into the special compensation model, and the special compensation model calculates the compensation pressure value required by the foundation pit according to the real-time strain increment and the specific requirements of the construction stage, to provide accurate compensation demand for the deformation compensation of the foundation pit. According to the calculation result, the compensation pressure value is generated, which represents the hydraulic pressure required to be applied in order to restore the design form of the foundation pit or to ensure the stability of the foundation pit.

[0068] Further, the special compensation model is called according to the real-time construction stage label, and the method comprises: A6241: According to the building structure characteristics of the construction foundation pit, a plurality of multi-construction stage deformation compensation records of a plurality of sample foundation pits are retrieved.

[0069] A6242: The plurality of multi-construction stage deformation compensation records are reorganized based on the construction stage to obtain P construction stage deformation compensation sets corresponding to P standard construction stages.

[0070] A6243: Regression analysis is performed on the P construction stage deformation compensation sets to construct P standard stage compensation functions.

[0071] A6244: P standard stage compensation models are constructed based on the P standard stage compensation functions.

[0072] A6245: Store the P standard construction stages and P standard stage compensation models to obtain a deformation compensation model library.

[0073] A6246: According to the real-time construction stage label, retrieve the special compensation model from the deformation compensation model library.

[0074] The building structure characteristics include the shape, depth, soil type, support method, etc. of the construction foundation pit, which determine the deformation behavior of the foundation pit and the possible deformation modes in different construction stages. Different building structure characteristics will lead to different deformation compensation needs. Multiple sample foundation pits refer to actual cases that have undergone similar foundation pit projects in the past construction. These cases contain deformation compensation records in multiple construction stages. The multiple construction stage deformation compensation records of the sample foundation pits refer to the deformation and compensation data of each sample foundation pit in multiple construction stages. By analyzing these sample data, similar compensation schemes can be provided for different types of foundation pits.

[0075] The reorganization process is to sort and classify multiple multi-construction stage deformation compensation records. For example, according to the support beam installation stage, the earth excavation stage, the backfilling stage, etc., the deformation and compensation data of each stage are classified. After reorganization, P construction stage deformation compensation sets of P standard construction stages are obtained, P is a positive integer, and each construction stage deformation compensation set of the standard construction stage contains multiple sample data that have undergone deformation compensation in that standard construction stage. Each construction stage deformation compensation set represents the characteristics of the foundation pit deformation and the compensation strategy in a specific construction stage.

[0076] Regression analysis is a statistical analysis method used to reveal the relationship between independent variables and dependent variables. In this step, regression analysis is performed on the P construction stage deformation compensation sets to find the mathematical model between deformation and compensation data, and to predict the deformation compensation needs in different construction stages. Through regression analysis, a standard stage compensation function is established for each construction stage, which describes the relationship between the deformation of the foundation pit in the corresponding construction stage and the required pressure compensation amount. The standard stage compensation function can be linear regression, nonlinear regression or other forms of functions, depending on the mode of foundation pit deformation and influencing factors.

[0077] Based on the P standard stage compensation functions, P standard stage compensation models are constructed. This process establishes a standard stage compensation model corresponding to each construction stage, providing a standardized calculation method for deformation compensation. Each standard stage compensation function describes the relationship between the deformation of the foundation pit in the corresponding construction stage and the required pressure compensation amount. Therefore, the constructed standard stage compensation model is a mathematical model that calculates the compensation pressure based on the deformation characteristics of the construction stage and other related variables (such as temperature, load changes, etc.).

[0078] The P standard construction stages are associated with and stored in relation to the corresponding P standard stage compensation models. Each standard construction stage is associated with a corresponding standard stage compensation model. This associated storage ensures that the compensation requirements of each standard construction stage can be calculated using the corresponding standard stage compensation model. The resulting deformation compensation model library is a database used to store all standard construction stages and their corresponding standard stage compensation models.

[0079] Based on the real-time construction stage label, a dedicated compensation model is retrieved from the deformation compensation model library. The dedicated compensation model performs calculations based on the construction stage to provide accurate pressure requirements for foundation pit deformation compensation.

[0080] Example 2, as Figure 3 As shown, this application provides a foundation pit deformation control system, wherein the system is used to implement the foundation pit deformation control method described in any one of Embodiment 1, and the system includes: A foundation pit deformation support system includes a concrete support beam 1 and a hydraulic jack 2. The piston end of the hydraulic jack 2 presses against the inner waler of the concrete support beam 1, and the cylinder end of the hydraulic jack 2 presses against the outer waler of the concrete support beam 1. A strain gauge 3 is installed inside the concrete support beam 1. A hydraulic station 6 includes a hydraulic power unit body and hydraulic oil pipes 7. The hydraulic station 6 is connected to the hydraulic jack 2 through the hydraulic oil pipes 7. The hydraulic station 6 is connected to a servo station 4 through a second data cable 8. The servo station 4 is fixedly installed on the ground around the foundation pit. The servo station 4 receives real-time strain data from the strain gauge 3 through the first data cable 5 to perform stress analysis on the support structure. After outputting a compensation pressure value, it sends the compensation pressure value to the hydraulic station 6 through the second data cable 8, controlling the hydraulic station 6 to dynamically adjust the hydraulic oil output pressure and drive the hydraulic jack 2 to perform hydraulic compensation for millimeter-level deformation of the foundation pit.

[0081] The core of the foundation pit deformation support system is to control the deformation of the foundation pit and ensure its stability during construction. The concrete support beam 1 is the main structural element of the foundation pit deformation support system. It bears and transmits the deformation pressure of the foundation pit through the waler structure. The deformation of the foundation pit may cause the soil to shrink or expand. Therefore, the concrete support beam 1 provides support to ensure the stability of the foundation pit. The hydraulic jack 2 is the power unit of the system. It is responsible for providing the necessary hydraulic pressure to compensate for the deformation of the foundation pit. Its piston end and cylinder end press against the inner and outer walers of the concrete support beam 1, respectively. The deformation of the foundation pit is adjusted by adjusting the pressure.

[0082] The strain gauge 3 is used to monitor the strain changes in the concrete support beam 1 in real time, which is directly embedded in the interior of the concrete support beam 1. By detecting the strain data, the deformation of the foundation pit during the construction process can be reflected.

[0083] The servo station 4 is connected with the strain gauge 3 through the first data lead 5, and is fixedly installed on the ground around the foundation pit. The servo station 4 is the control center of the whole system, responsible for receiving the strain data from the strain gauge 3, and analyzing these strain data to calculate the required compensation pressure value. The servo station 4 is connected with the strain gauge 3 through the first data lead 5 to receive the strain data transmitted by the strain gauge 3.

[0084] The oil pressure station 6 is the hydraulic power unit of the whole system, responsible for providing hydraulic oil and adjusting the working pressure of the oil pressure jack 2 to compensate for the deformation of the foundation pit. The hydraulic power unit body is the core component of the oil pressure station 6, including a hydraulic oil pump, an oil tank and other parts. The hydraulic power unit body provides the energy required by the hydraulic system, drives the hydraulic oil pump to send the oil pressure into the hydraulic oil pipe 7, and the hydraulic oil pipe 7 is used to transmit the oil pressure of the hydraulic power unit body to the oil pressure jack 2. By controlling the oil pressure in the hydraulic oil pipe 7, the oil pressure station 6 can affect the action of the oil pressure jack 2, and thus adjust the deformation of the foundation pit support structure.

[0085] The oil pressure station 6 is connected with the servo station 4 through the second data lead 8 to transmit the compensation pressure value calculated by the servo station 4 to the oil pressure station 6, so that the oil pressure station 6 can receive the correct compensation requirement and reduce the delay and error in the transmission process.

[0086] The servo station 4 receives the real-time strain data of the strain gauge 3 through the first data lead 5, which reflects the deformation of the concrete support beam 1. The servo station 4 analyzes the stress of the support structure according to the real-time strain data and calculates the required compensation pressure value. Then, the servo station 4 outputs the calculation result and sends the compensation pressure value to the oil pressure station 6 through the second data lead 8. After receiving the compensation pressure value, the oil pressure station 6 controls the output pressure of the hydraulic oil to drive the oil pressure jack 2 to compensate for the deformation. By adjusting the oil pressure jack 2, the deformation of the foundation pit can be accurately compensated for, ensuring the stability and safety of the foundation pit. Overall, the whole system can quickly respond to the real-time deformation of the foundation pit, avoid excessive deformation of the foundation pit through real-time monitoring and adjustment, and ensure the safety of the construction.

[0087] Further, the oil pressure jack 2 further comprises: A steel sleeve box, in which the oil pressure jack 2 is installed. A falling prevention steel beam 9 is vertically welded to the top of the steel sleeve box, and the first end and the second end of the falling prevention steel beam 9 are respectively hung on the inner side purlin and the outer side purlin of the concrete support beam 1.

[0088] The steel box is the external structure of the oil jack 2, mainly used to provide physical protection and support, the oil jack 2 is installed inside the steel box, which can effectively protect the oil jack 2 from the external environment, especially in the foundation pit construction environment, the steel box can prevent water, soil or other materials from corroding and damaging the oil jack 2.

[0089] The anti-falling steel beam 9 is a safety component in the overall structure of the oil jack 2, its main function is to prevent the oil jack 2 from falling or position deviation during installation or work. The anti-falling steel beam 9 is vertically welded on the top of the steel box, ensuring its firm connection and being able to withstand possible weight and external force. The first end and the second end of the anti-falling steel beam 9 are respectively hung on the inner side purlin and the outer side purlin of the concrete support beam 1. Through this structure, the anti-falling steel beam 9 firmly connects the oil jack 2 with the concrete support beam, which can prevent accidents and ensure the stable working state of the oil jack 2 during the foundation pit construction process due to complex ground conditions or drastic changes in the construction environment.

[0090] Further, the foundation pit deformation support system further comprises: The load-bearing steel plate 10 is pre-buried in the inner side purlin of the concrete support beam 1, and the piston end of the oil jack 2 presses the load-bearing steel plate 10.

[0091] The load-bearing steel plate 10 is an important component in the foundation pit deformation support system, which is mainly used to distribute the pressure from the piston end of the oil jack 2 to the concrete support beam 1, ensuring uniform distribution of pressure and enhancing the stability of the support structure. The load-bearing steel plate 10 is pre-buried in the inner side purlin of the concrete support beam 1 and fixed in the concrete structure, ensuring that it is not easily displaced or fallen off, and the piston end of the oil jack 2 presses the load-bearing steel plate 10, which uniformly transmits this pressure to the concrete support beam 1. In this way, the force exerted by the oil jack 2 can be effectively distributed to the entire concrete support beam 1, thereby reducing the risk of structural damage caused by excessive local stress.

[0092] Further, the strain gauge 3 is series-welded at the reserved position of the main reinforcement inside the concrete support beam 1.

[0093] The strain gauge 3 is welded in series at a reserved position of a force main reinforcement inside the concrete support beam 1, the force main reinforcement is a steel bar in the concrete structure which bears most of the force, usually located in the core area of the structure, the reserved position is usually an area where force concentration is considered in the design, the purpose of welding the strain gauge 3 is to directly perceive the force change of the force concentration area, at this reserved position, the deformation of the concrete support beam 1 is most significant, therefore the strain gauge 3 can accurately reflect the deformation of the foundation pit during the construction process.

[0094] Any one of the above methods or steps can be stored as computer instructions or programs in various types of computer memories, and the computer instructions or programs can be recognized by various types of computer processors, thereby realizing any one of the above methods or steps.

[0095] Based on the above specific embodiments of the present application, any improvement and modification of the present application made by those skilled in the art without departing from the principles of the present application shall fall within the scope of the patent protection of the present application.

Claims

1. A method for controlling the deformation of a foundation pit, characterized in that, The method includes: The servo station accumulates the strain data transmitted back from the strain gauges and generates time-series strain data; The time-series strain data is subjected to STL time-series decomposition of the foundation pit deformation characteristics to obtain deformation trend term characteristics, deformation period term characteristics, and deformation residual term characteristics; Based on the deformation trend term features, deformation period term features and deformation residual term features, the time-series deformation prediction of the foundation pit is performed, and the foundation pit strain prediction data is output. Based on the predicted strain data of the foundation pit, the deformation intervention requirements are derived, and the pre-compensation time-series pressure is output. The hydraulic station receives and adjusts the hydraulic oil output pressure according to the pre-compensated timing pressure to drive the hydraulic jack to perform predictive deformation compensation of the foundation pit.

2. The foundation pit deformation control method as described in claim 1, characterized in that, The time-series strain data is subjected to STL time-series decomposition of the foundation pit deformation characteristics to obtain deformation trend term characteristics, deformation period term characteristics, and deformation residual term characteristics. The method includes: The cumulative deformation rate of the concrete-supported beam is tracked using the time-series strain data, and the deformation trend feature is output. Based on the start and end timestamps of the time-series strain data, the time-series ambient temperature data and time-series construction disturbance data are retrieved synchronously. By aligning the time-series environmental temperature data and time-series strain data, Fourier spectrum analysis is used to capture the periodic fluctuations in strain caused by temperature, thereby obtaining the characteristics of the deformation periodic term. Align the time-series construction disturbance data and time-series strain data, calculate and predict the intensity of random fluctuations using the sliding window standard deviation, and output the characteristics of the deformation residual term.

3. The method for controlling foundation pit deformation as described in claim 2, characterized in that, Based on the aforementioned deformation trend term features, deformation period term features, and deformation residual term features, the time-series deformation prediction of the foundation pit is performed, and the foundation pit strain prediction data is output. The method includes: A component prediction model is constructed based on historical data, wherein the component prediction model includes parallel trend prediction sub-model, period prediction sub-model and residual prediction sub-model. The deformation trend feature is loaded into the trend prediction sub-model to predict the cumulative deformation of the foundation pit, and the cumulative deformation is output. The deformation periodicity feature is loaded into the periodic prediction sub-model to predict the temperature deformation of the foundation pit and output the temperature deformation amount. The deformed residual term features are loaded into the residual prediction sub-model to predict the perturbation fluctuation range and output the random perturbation amount; The cumulative deformation, temperature deformation, and random disturbance are linearly superimposed to generate the foundation pit strain prediction data.

4. The method for controlling foundation pit deformation as described in claim 1, characterized in that, The method further includes: The servo station receives real-time strain data transmitted back from the strain gauge via the first data cable; The real-time strain data is subjected to safety verification. If the real-time strain data exceeds a preset safety threshold, the deformation compensation requirement is calculated based on the real-time strain increment after calculating the real-time strain data, and the compensation pressure value is output. The servo station sends the compensation pressure value to the hydraulic station via the second data cable; The hydraulic station receives and adjusts the hydraulic oil output pressure according to the compensation pressure value, driving the hydraulic jack to perform low-delay hydraulic compensation for millimeter-level deformation of the foundation pit.

5. The method for controlling foundation pit deformation as described in claim 4, characterized in that, After calculating the real-time strain increment of the real-time strain data, the deformation compensation requirement is calculated based on the real-time strain increment, and the compensation pressure value is output. The method includes: Based on the acquisition timestamp of the real-time strain data, match the real-time construction stage tags in the foundation pit construction log; Starting from the acquisition timestamp of the real-time strain data, historical strain records are traced back to obtain a short-term strain data stream; Incremental features are extracted from the real-time strain data based on the short-term strain data stream to obtain the real-time strain increment, wherein the real-time strain increment includes the increment amplitude, increment acceleration, and over-threshold time window; The dedicated compensation model is retrieved based on the real-time construction stage tags; The real-time strain increment is input into the dedicated compensation model to calculate the deformation compensation requirement and output the compensation pressure value.

6. The method for controlling foundation pit deformation as described in claim 5, characterized in that, The method for retrieving a dedicated compensation model based on the real-time construction stage tags includes: Based on the architectural structural characteristics of the construction pit, multiple deformation compensation records for multiple sample pits at multiple construction stages were retrieved. Based on the reconstruction of the multiple multi-construction stage deformation compensation records during the construction stage, P construction stage deformation compensation sets corresponding to P standard construction stages are obtained. Regression analysis is performed on the P deformation compensation sets for each construction stage to construct P standard stage compensation functions; Construct a P-standard-stage compensation model based on the P-standard-stage compensation functions; The P standard construction stages and P standard stage compensation models are associated and stored to obtain a deformation compensation model library; Based on the real-time construction stage label, the dedicated compensation model is retrieved from the deformation compensation model library.

7. A foundation pit deformation control system, characterized in that, The system is used to implement the foundation pit deformation control method according to any one of claims 1-6, the system comprising: The foundation pit deformation support system includes a concrete support beam (1) and a hydraulic jack (2). The piston end of the hydraulic jack (2) presses against the inner waler of the concrete support beam (1), and the cylinder end of the hydraulic jack (2) presses against the outer waler of the concrete support beam (1). Strain gauge (3), the strain gauge (3) is disposed inside the concrete support beam (1); The hydraulic station (6) includes a hydraulic power unit body and a hydraulic oil pipe (7). The hydraulic station (6) is connected to the hydraulic jack (2) through the hydraulic oil pipe (7). The hydraulic station (6) is connected to the servo station (4) through a second data cable (8). The servo station (4) is fixedly installed on the ground around the foundation pit. The servo station (4) receives real-time strain data from the strain gauge (3) via the first data wire (5) to perform stress analysis on the support structure. After outputting the compensation pressure value, it sends the compensation pressure value to the hydraulic station (6) via the second data wire (8) to control the hydraulic station (6) to dynamically adjust the hydraulic oil output pressure and drive the hydraulic jack (2) to perform hydraulic compensation for millimeter-level deformation of the foundation pit.

8. The foundation pit deformation control system as described in claim 7, characterized in that, The hydraulic jack also includes: A steel housing, wherein the hydraulic jack (2) is installed inside the steel housing; The anti-fall steel beam (9) is vertically welded to the top of the steel casing. The first end and the second end of the anti-fall steel beam (9) are respectively suspended from the inner waler and the outer waler of the concrete support beam (1).

9. The foundation pit deformation control system as described in claim 7, characterized in that, The foundation pit deformation support system also includes: A load-bearing steel plate (10) is embedded in the inner waler of the concrete support beam (1), and the piston end of the hydraulic jack (2) presses against the load-bearing steel plate (10).

10. The foundation pit deformation control system as described in claim 7, characterized in that, The strain gauge (3) is welded in series to the reserved position of the main reinforcing bar inside the concrete support beam (1).

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