Foundation pit deformation control method and system

Abstract

The application provides a foundation pit deformation control method and system, and relates to the technical field of foundation pit support engineering, wherein the method comprises the following steps: 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 performed to obtain deformation trend item characteristics, deformation period item characteristics and deformation residual item characteristics; foundation pit time sequence deformation prediction is performed to output foundation pit strain prediction data; deformation intervention requirement derivation is performed to output pre-compensation time sequence pressure; and time sequence adjustment of hydraulic oil output pressure is performed to drive an oil pressure jack to perform foundation pit predictive deformation compensation. The technical problem that traditional foundation pit support relies on the preset prestress of a concrete support beam, cannot dynamically adjust according to the deformation occurring in the actual excavation process of the foundation pit, and leads to the fact that the foundation pit deformation cannot be effectively controlled, and the risk of instability of the foundation pit is increased is solved, and the technical effect that the real-time performance and accuracy of foundation pit deformation compensation are improved is achieved.

Description

Technical Field

[0001] This invention relates to the field of foundation pit support engineering technology, specifically to a method and system for controlling foundation pit deformation. Background Technology

[0002] In foundation pit engineering, the design and control of the support system are crucial, especially in deep foundation pits or complex geological conditions. Traditional foundation pit support systems typically employ a passive force-bearing mode, relying on the pre-stressed concrete supports for support. However, this method suffers from the inability to dynamically adjust with excavation. As foundation pit construction progresses, the excavation of the surrounding soil causes deformation of the foundation pit, and the fixed prestressed supports cannot effectively respond to these dynamic deformations, leading to uncontrollable deformation of the retaining structure. This poses a risk to construction safety and the stability of the foundation pit. Furthermore, existing servo supports mostly use steel support systems. While they offer some adjustability in certain situations, steel supports generally lack sufficient stiffness and are prone to instability, unable to withstand excessive external forces or deformations. This limits the application of steel supports in controlling foundation pit deformation. Summary of the Invention

[0003] This application provides a method and system for controlling foundation pit deformation, which addresses the technical problem that traditional foundation pit support relies on the pre-stressed concrete support beams, which cannot be dynamically adjusted according to the deformation that occurs during the actual excavation of the foundation pit, resulting in the inability to effectively control the foundation pit deformation and increasing the risk of foundation pit instability.

[0004] In view of the above problems, this application provides a method and system for controlling the deformation of foundation pits.

[0005] A first aspect of this application provides a method for controlling the deformation of a foundation pit, the method comprising:

[0006] The servo station accumulates and receives strain data from strain gauges, generating time-series strain data. It then performs STL time-series decomposition of the pit deformation characteristics on the time-series strain data to obtain deformation trend features, deformation period features, and deformation residual features. Based on these features, it predicts the pit's time-series deformation and outputs pit strain prediction data. Based on the pit strain prediction data, it derives deformation intervention requirements and outputs pre-compensation time-series pressure. The hydraulic station receives and 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 pit.

[0007] A second aspect of this application provides a foundation pit deformation control system, the system comprising:

[0008] A foundation pit deformation support system includes a concrete support beam and hydraulic jacks. The piston end of the hydraulic jack presses against the inner waler of the concrete support beam, and the cylinder end of the hydraulic jack presses against the outer waler of the concrete support beam. A strain gauge is installed inside the concrete support beam. A servo station is connected to the strain gauge via a first data cable and is fixedly installed on the ground around the foundation pit. A hydraulic station includes a hydraulic power unit and hydraulic pipes. The hydraulic station is connected to the hydraulic jacks via hydraulic pipes and connected to the servo station via a second data cable. The servo station is fixedly installed on the ground around the foundation pit. The servo station receives real-time strain data from the strain gauges via the first data cable to perform stress analysis on the support structure. After outputting a compensation pressure value, it sends the compensation pressure value to the hydraulic station via the second data cable, controlling the hydraulic station to dynamically adjust the hydraulic oil output pressure and drive the hydraulic jacks to perform hydraulic compensation for millimeter-level deformation of the foundation pit.

[0009] One or more technical solutions provided in this application have at least the following technical effects or advantages:

[0010] 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

[0011] Figure 1 A schematic diagram of the foundation pit deformation control method provided in this application.

[0012] Figure 2 A schematic diagram of the STL time sequence decomposition process in the foundation pit deformation control method provided in this application.

[0013] Figure 3 A schematic diagram of the structure of the foundation pit deformation control system provided in this application.

[0014] 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

[0015] This application provides a method and system for controlling foundation pit deformation, which addresses the technical problem that traditional foundation pit support relies on the pre-stressed concrete support beams, which cannot be dynamically adjusted according to the deformation that occurs during the actual excavation of the foundation pit, resulting in the inability to effectively control the foundation pit deformation and increasing the risk of foundation pit instability.

[0016] The technical solutions of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. It should be understood that the present invention is not limited to the exemplary embodiments described herein. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention. It should also be noted that, for ease of description, only the parts related to the present invention are shown in the accompanying drawings, not all of them.

[0017] Example 1, as Figure 1 As shown, this application provides a method for controlling the deformation of a foundation pit, the method comprising:

[0018] A100: The servo station accumulates the strain data received from the strain gauges and generates time-series strain data.

[0019] The servo station receives strain data transmitted back from the strain gauges. The strain gauges monitor the strain, i.e., the deformation, at different parts of the foundation pit. The servo station accumulates the received strain data in chronological order to construct a time series of strain data, i.e., time-series strain data. Each data point represents the strain of the foundation pit at a certain time stamp. The time-series strain data records the deformation process of the foundation pit, which is convenient for further analysis of the deformation characteristics of the foundation pit.

[0020] A200: Perform STL time-series decomposition on the time-series strain data to obtain the deformation trend term characteristics, deformation period term characteristics, and deformation residual term characteristics.

[0021] STL (Series Strength-Layer Transformation) is a method for extracting temporal features from time-series data. STL decomposes time-series strain data into three parts: a deformation trend term representing the long-term trend of foundation pit deformation (extracted by applying local weighted regression smoothing to the data); a deformation period term representing periodic variations related to environmental changes (such as temperature changes) and construction disturbances (capturing periodic fluctuations in foundation pit deformation); and a deformation residual term representing the portion of the time-series strain data that cannot be explained by the trend and period terms, caused by random disturbances or unforeseen factors (such as sudden construction disturbances). In the STL decomposition process, environmental temperature data and construction disturbance data are combined, using techniques such as Fourier spectrum analysis to capture periodic fluctuations related to temperature changes, and methods such as sliding windows to assess random fluctuations caused by construction disturbances. After STL decomposition, the aforementioned deformation trend, deformation period, and deformation residual terms are obtained.

[0022] A300: 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.

[0023] Based on historical data, a multi-component prediction model is constructed, including a trend prediction sub-model, a periodic prediction sub-model, and a residual prediction sub-model. The trend prediction sub-model predicts the cumulative deformation of the foundation pit based on deformation trend characteristics, using historical trend data to predict future deformation trends. The periodic prediction sub-model predicts the deformation of the foundation pit under different temperature conditions based on deformation periodic characteristics, predicting possible future periodic deformation by modeling periodic deformation data. The residual prediction sub-model predicts the disturbance fluctuations of the foundation pit based on deformation residual characteristics, predicting possible future random fluctuations by analyzing historical disturbance data. The prediction results of each sub-model are combined through linear superposition; that is, the cumulative deformation of the foundation pit, the deformation caused by temperature, and the random fluctuations caused by disturbances are added together to obtain the final foundation pit strain prediction data, which includes the future strain change trend of the foundation pit.

[0024] A400: 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.

[0025] Based on the predicted strain data of the foundation pit, the future deformation of the pit is analyzed to determine whether the predicted strain exceeds the safety threshold. The goal is to identify the intervention points and derive the corresponding deformation compensation requirements. Based on the derived deformation compensation requirements, the corresponding compensation pressure value is calculated. This compensation pressure value is derived from the predicted strain, trend, and intervention requirements, indicating how much hydraulic pressure should be applied at different times to compensate for the foundation pit deformation. The intervention points and corresponding compensation pressure values ​​are arranged chronologically to form a pre-compensation time-series pressure, which is a time-synchronized pressure curve that indicates how the hydraulic station should adjust the pressure to compensate for the predicted deformation of the foundation pit.

[0026] A500: The hydraulic station receives and adjusts the hydraulic oil output pressure according to the pre-compensation timing pressure to drive the hydraulic jack to perform predictive deformation compensation of the foundation pit.

[0027] The hydraulic station receives the pre-compensation timing pressure. Based on this pressure, the station adjusts the output pressure of the hydraulic oil. By adjusting the oil pressure output, the station controls the movement of the hydraulic jacks. The hydraulic jacks are used to perform actual deformation compensation of the foundation pit, ensuring that excessive deformation does not occur. During this process, the hydraulic jacks provide corresponding force to control the deformation of the foundation pit. The adjustment of the output pressure is precise, ensuring that the oil pressure output matches the predicted compensation pressure value. For example, if a large deformation of the foundation pit is predicted at a certain moment, the hydraulic station will output a higher hydraulic pressure to compensate for this deformation. By adjusting the hydraulic station to actually drive the hydraulic jacks, predictive deformation compensation of the foundation pit is achieved, ensuring that the deformation of the foundation pit remains within a controllable range.

[0028] Furthermore, such as Figure 2 As shown, the time-series strain data is subjected to STL time-series decomposition of the foundation pit deformation characteristics to obtain deformation trend term features, deformation period term features, and deformation residual term features. The method includes:

[0029] A210: Track the cumulative deformation rate of the concrete support beam using the time-series strain data, and output the deformation trend feature.

[0030] A220: Based on the start and end timestamps of the time-series strain data, synchronously retrieve the time-series environmental temperature data and the time-series construction disturbance data.

[0031] A230: Align the time-series environmental temperature data and time-series strain data, and use Fourier spectrum analysis to capture the periodic fluctuations in strain caused by temperature, thereby obtaining the characteristics of the deformation periodic term.

[0032] A240: 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.

[0033] 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.

[0034] 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.

[0035] 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.

[0036] 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.

[0037] 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.

[0038] Fourier spectrum analysis is a signal analysis method that converts signals in the time domain into signals in the frequency domain, revealing the periodic components within the signal. In the analysis of foundation pit deformation, temperature changes are typically periodic, such as diurnal temperature variations and seasonal changes. These temperature fluctuations cause the expansion or contraction of the foundation pit materials, leading to deformation. Fourier spectrum analysis identifies the frequency components of these temperature-induced periodic fluctuations. Specifically, it uses Fourier transform to convert the periodic fluctuations in time-series environmental temperature data into frequency domain data, thus revealing how temperature changes affect the periodic deformation of the foundation pit. The periodic components obtained through Fourier spectrum analysis serve as a feature term for deformation periodicity. This feature 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.

[0039] Similarly, time-series strain data and time-series construction disturbance data are aligned to analyze the impact of disturbances occurring during construction on the deformation of the foundation pit, and to identify the random impact of unforeseen factors during construction on the deformation of the foundation pit.

[0040] Sliding window standard deviation is a method used in time series analysis. By defining a time window, the standard deviation of the data within that window is calculated to reflect the degree of data fluctuation. In this step, the sliding window standard deviation is applied to time-series strain data and time-series construction disturbance data to calculate the intensity of strain fluctuation within each time window. The relationship between construction disturbance data and strain data within each time window reveals the impact of construction disturbance on foundation pit deformation. The standard deviation calculation result is used to quantify the intensity of random fluctuations, 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 term feature is extracted. This feature represents the fluctuation in foundation pit deformation caused by construction disturbance. The deformation residual term feature is different from the periodic deformation feature; it represents the random fluctuation component that cannot be explained by trend and periodic terms. This feature is used to identify and predict irregular deformation during construction.

[0041] Furthermore, 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 foundation pit strain prediction data is output. The method includes:

[0042] A310: Construct a component prediction model based on historical data, wherein the component prediction model includes parallel trend prediction sub-model, period prediction sub-model and residual prediction sub-model.

[0043] A320: Load the deformation trend feature into the trend prediction sub-model to predict the cumulative deformation of the foundation pit and output the cumulative deformation amount.

[0044] 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.

[0045] 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.

[0046] A350: The cumulative deformation, temperature deformation, and random disturbance are linearly superimposed to generate the foundation pit strain prediction data.

[0047] 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.

[0048] 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.

[0049] 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.

[0050] The extracted deformation periodicity features are input into the periodic prediction sub-model. These features represent the deformation period of the foundation pit related to external periodic factors such as temperature. They help the periodic prediction sub-model capture how temperature changes affect the expansion or contraction of the foundation pit material, thus affecting the periodic deformation of the foundation pit. The periodic prediction sub-model uses these features to predict the foundation pit deformation caused by temperature changes. By analyzing the relationship between temperature and deformation in historical data, it predicts the impact of future temperature changes on the foundation pit, such as how the foundation pit expands when the temperature rises and how it contracts when the temperature falls. The final output is the temperature deformation amount, which is the amount of deformation of the foundation pit caused by temperature changes.

[0051] The extracted deformation residual term features are input into the residual prediction sub-model. The deformation residual term features represent random fluctuation components that cannot be explained by the trend term and periodic term. The residual prediction sub-model uses the deformation residual term features to predict the intensity or fluctuation range of the foundation pit caused by construction disturbance or other random factors. After prediction, the random disturbance quantity is output, which is the intensity of random deformation fluctuation that the foundation pit may experience in the future. The random disturbance quantity is usually fluctuating and closely related to time, construction progress or environmental changes.

[0052] The cumulative deformation, temperature deformation, and random disturbance outputs are linearly superimposed. This means that by adding these three deformations together, a total predicted deformation of the foundation pit is obtained, which serves as the foundation pit strain prediction data. This data represents the overall deformation prediction of the foundation pit under the combined effects of multiple factors. This foundation pit strain prediction data integrates long-term deformation trends, periodic fluctuations caused by temperature, and random fluctuations caused by construction disturbances, providing comprehensive information for the prediction of foundation pit deformation.

[0053] Furthermore, the method also includes:

[0054] A610: The servo station receives real-time strain data transmitted back from the strain gauge via the first data cable.

[0055] A620: Perform safety verification on the real-time strain data. If the real-time strain data exceeds a preset safety threshold, calculate the real-time strain increment of the real-time strain data, calculate the deformation compensation requirement based on the real-time strain increment, and output the compensation pressure value.

[0056] A630: The servo station sends the compensation pressure value to the hydraulic station via the second data cable.

[0057] A640: The hydraulic station receives and adjusts the hydraulic oil output pressure according to the compensation pressure value to drive the hydraulic jack to perform low-delay hydraulic compensation for millimeter-level deformation of the foundation pit.

[0058] The function of the first data cable is to transmit the real-time strain data measured by the strain gauge from the strain gauge to the servo station, reducing delays and errors during data transmission. The servo station is connected to the strain gauge via the first data cable and receives the real-time strain data transmitted back by the strain gauge. The real-time strain data reflects the real-time deformation at different locations in the foundation pit.

[0059] The received real-time strain data is subjected to safety verification. Safety verification 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 there is a safety hazard. Deformation compensation is required to avoid structural damage or safety accidents.

[0060] In this scenario, the real-time strain increment is calculated. The real-time strain increment refers to the current real-time strain data relative to historical strain records regarding the foundation pit deformation. It reflects the recent deformation pattern or the impact of sudden events (such as construction disturbance or soil settlement) on the foundation pit's deformation. Based on the calculated real-time strain increment, the deformation compensation requirement is calculated. This calculation process combines the magnitude of the real-time strain increment, the location of the deformation, and the required compensation pressure to arrive at the compensation pressure value. This compensation pressure value represents the hydraulic pressure that the hydraulic station needs to apply to compensate for the current deformation of the foundation pit.

[0061] The second data cable is used to transmit the compensation pressure value calculated by the servo station to the hydraulic station, so that the hydraulic station can receive the correct compensation requirements and reduce delays and errors during transmission. The servo station sends the calculated compensation pressure value to the hydraulic station via the second data cable to respond to pit deformation in real time.

[0062] After receiving the compensation pressure value from the servo station, the hydraulic station begins to adjust its hydraulic oil output pressure. The hydraulic oil output pressure directly affects the action of the hydraulic jack. The hydraulic oil output pressure and the compensation pressure value are precisely matched to ensure that the deformation of the foundation pit is properly compensated.

[0063] Hydraulic jacks are key devices for performing deformation compensation. They use hydraulic oil pressure to push or pull the support structure of the foundation pit, restoring the pit to its designed shape. The action of hydraulic jacks can provide high-precision compensation for millimeter-level deformation of the foundation pit. During the deformation compensation process, low latency means that compensation is performed in real time. Any delay may lead to the deterioration of the foundation pit deformation and increase construction risks. The hydraulic station achieves low-latency hydraulic compensation by quickly responding to the compensation pressure value. This means that the hydraulic station can quickly adjust the hydraulic system and drive the hydraulic jacks in real time to perform foundation pit deformation compensation, ensuring the timeliness and accuracy of deformation compensation.

[0064] Furthermore, 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:

[0065] A621: Based on the acquisition timestamp of the real-time strain data, match the real-time construction stage label in the foundation pit construction log.

[0066] A622: 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.

[0067] A623: Based on the short-term strain data stream, incremental features are extracted from the real-time strain data to obtain the real-time strain increment, wherein the real-time strain increment includes the increment amplitude, the increment acceleration, and the time window exceeding the threshold.

[0068] A624: Retrieve the dedicated compensation model based on the real-time construction stage tags.

[0069] A625: Input the real-time strain increment into the dedicated compensation model to calculate the deformation compensation requirement and output the compensation pressure value.

[0070] The timestamp of real-time strain data acquisition indicates the specific time of data acquisition. The foundation pit construction log is a file recording key activities and stages during the foundation pit construction process. It includes information such as the time, activities, potential environmental changes, and progress of each construction stage. By matching the real-time construction stage tag corresponding to the timestamp of the real-time strain data acquisition from the foundation pit construction log, the log is updated. This tag indicates the current stage of the foundation pit, such as excavation, support installation, or backfilling. Different stages of construction activities will have different impacts on the foundation pit.

[0071] Starting from the acquisition timestamp of real-time strain data, the data is traced back to historical strain records, which contain all strain data prior to the excavation pit. The tracing process involves retrieving data from several hours or days prior to the acquisition timestamp, depending on the monitoring cycle of the excavation pit deformation and the acquisition frequency of strain data. Based on the tracing results, a short-term strain data stream is obtained. The short-term strain data stream represents the deformation of the excavation pit over a relatively short period of time since the acquisition timestamp, and is used to compare and analyze the strain increment of the excavation pit under its current state.

[0072] By comparing real-time strain data with short-term strain data streams, incremental features are extracted. Incremental features refer to the changes in the deformation of the foundation pit over a relatively short period of time, especially the changes compared with previous strain data. The deformation increment is calculated by comparing short-term strain data streams and real-time strain data.

[0073] The incremental amplitude represents the change in foundation pit deformation. Specifically, it refers to the magnitude of change in real-time strain data relative to the short-term strain data stream. The larger the incremental amplitude, the more significant the deformation of the foundation pit. The incremental acceleration refers to the change in the deformation rate of the foundation pit, that is, the rate of change of the incremental deformation per unit time. Incremental acceleration helps to identify abrupt changes in the deformation process, usually caused by sudden disturbances or uneven settlement. The threshold time window represents the time window during which the strain increment exceeds a preset safety threshold. In some cases, the strain increment of the foundation pit may exceed a certain safety limit. In this case, recording this time period indicates which deformation changes have exceeded the safety range and require timely intervention. Based on the above incremental feature extraction, the real-time strain increment is obtained, including the amplitude, rate, and duration of deformation. This information provides a key basis for subsequent calculation of deformation compensation requirements.

[0074] Based on the real-time construction stage labels, the corresponding dedicated compensation model is retrieved. Different construction stages lead to different deformation characteristics, therefore, it is necessary to select an appropriate compensation model according to the construction stage. For example, during the support beam installation stage, the foundation pit deformation may be caused by changes in the support beam load, while during the backfilling stage, it may be caused by soil settlement or structural consolidation. Therefore, different stages require different compensation strategies, and the corresponding compensation model is retrieved based on the construction stage labels. The dedicated compensation model is designed for different construction stages and is used to calculate the compensation requirements for foundation pit deformation.

[0075] The calculated real-time strain increment is input into a dedicated compensation model. Based on the real-time strain increment and the specific requirements of the construction stage, the dedicated compensation model calculates the compensation pressure value required for the foundation pit, providing accurate compensation requirements for foundation pit deformation compensation. The compensation pressure value is generated based on the calculation results, representing the hydraulic pressure required to restore the design shape of the foundation pit or ensure the stability of the foundation pit.

[0076] Furthermore, the method of retrieving a dedicated compensation model based on the real-time construction stage tags includes:

[0077] A6241: Based on the architectural structural characteristics of the construction pit, retrieve multiple deformation compensation records for multiple sample pits at multiple construction stages.

[0078] A6242: 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.

[0079] A6243: Perform regression analysis on the P sets of deformation compensation for each construction stage to construct P standard stage compensation functions.

[0080] A6244: Construct a P standard stage compensation model based on the P standard stage compensation functions.

[0081] A6245: Associate the P standard construction stages and the P standard stage compensation models to obtain a deformation compensation model library.

[0082] A6246: Based on the real-time construction stage label, retrieve the dedicated compensation model from the deformation compensation model library.

[0083] Structural features of a construction pit include its shape, depth, soil type, and support method. These features determine the pit's deformation behavior and potential deformation patterns at different construction stages. Different structural features lead to different deformation compensation requirements. Multiple sample pits refer to actual cases of similar pit projects that have been carried out in the past. These cases include deformation compensation records across multiple construction stages. The multi-stage deformation compensation records of the sample pits refer to the deformation and compensation data of each sample pit at multiple construction stages. By analyzing this sample data, similar compensation schemes can be provided for different types of pits.

[0084] The reorganization process involves organizing and classifying deformation compensation records from multiple construction stages. For example, deformation and compensation data for each stage can be categorized according to the support beam installation stage, earthwork excavation stage, and backfilling stage. After reorganization, P standard construction stage deformation compensation sets are obtained, where P is a positive integer. Each standard construction stage deformation compensation set contains multiple sample data of deformation compensation performed in that standard construction stage. Each construction stage deformation compensation set represents the characteristics and compensation strategies of foundation pit deformation in a specific construction stage.

[0085] Regression analysis is a statistical method used to reveal the relationship between independent and dependent variables. In this step, regression analysis is performed on P sets of deformation compensation data for different construction stages to find a mathematical model between deformation and compensation data, thereby predicting the deformation compensation requirements for different construction stages. Through regression analysis, a standard stage compensation function is established for each construction stage. This standard stage compensation function describes the relationship between the foundation pit deformation and the required pressure compensation for the corresponding construction stage. The standard stage compensation function can be linear regression, nonlinear regression, or other forms of function, depending on the pattern and influencing factors of the foundation pit deformation.

[0086] Based on P standard stage compensation functions, a P standard stage compensation model is 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 foundation pit deformation and the required pressure compensation amount for the corresponding construction stage. 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 relevant variables (such as temperature and load changes).

[0087] 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.

[0088] 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.

[0089] 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:

[0090] 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.

[0091] 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.

[0092] The strain gauge 3 is used to monitor the strain changes in the concrete support beam 1 in real time. It is directly embedded in the interior of the concrete support beam 1. By detecting the strain data, it can reflect the deformation of the foundation pit during the construction process.

[0093] Servo station 4 is connected to strain gauge 3 via a first data cable 5. Servo station 4 is fixedly installed on the ground around the foundation pit. Servo station 4 is the control center of the entire system. It is responsible for receiving strain data from strain gauge 3, analyzing the strain data, and calculating the required compensation pressure value. Servo station 4 is connected to strain gauge 3 via the first data cable 5 and receives the strain data transmitted by strain gauge 3.

[0094] Hydraulic station 6 is the hydraulic power unit of the entire system. It is responsible for supplying hydraulic oil and regulating the working pressure of hydraulic jack 2 to compensate for the deformation of the foundation pit. The hydraulic power unit body is the core component of hydraulic station 6, including a hydraulic oil pump, oil tank, etc. The hydraulic power unit body provides the energy required by the hydraulic system and drives the hydraulic oil pump to send the oil pressure into the hydraulic oil pipe 7. The hydraulic oil pipe 7 is used to transmit the oil pressure of the hydraulic power unit body to the hydraulic jack 2. By controlling the oil pressure in the hydraulic oil pipe 7, hydraulic station 6 can affect the movement of hydraulic jack 2, thereby adjusting the deformation of the foundation pit support structure.

[0095] The hydraulic station 6 is connected to the servo station 4 via the second data cable 8. The compensation pressure value calculated by the servo station 4 is transmitted to the hydraulic station 6 so that the hydraulic station 6 can receive the correct compensation requirements and reduce the delay and error in the transmission process.

[0096] Servo station 4 receives real-time strain data from strain gauge 3 via the first data cable 5. This real-time strain data reflects the deformation within the concrete support beam 1. Servo station 4 performs stress analysis on the support structure based on the real-time strain data and calculates the required compensation pressure value. Then, servo station 4 outputs the calculation result and sends the compensation pressure value to hydraulic station 6 via the second data cable 8. Upon receiving the compensation pressure value, hydraulic station 6 controls the output pressure of the hydraulic oil to drive hydraulic jack 2 for deformation compensation. By adjusting hydraulic jack 2, the deformation of the foundation pit can be precisely compensated, ensuring the stability and safety of the foundation pit. Overall, the entire system can react quickly to the real-time deformation of the foundation pit, preventing excessive deformation through real-time monitoring and adjustment, thus ensuring construction safety.

[0097] Furthermore, the hydraulic jack 2 also includes:

[0098] A steel casing, with the hydraulic jack 2 installed inside the steel casing; a fall-prevention steel beam 9, which is vertically welded to the top of the steel casing, with the first and second ends of the fall-prevention steel beam 9 suspended from the inner and outer walers of the concrete support beam 1, respectively.

[0099] The steel casing is the external structure of the hydraulic jack 2, mainly used to provide physical protection and support. The hydraulic jack 2 is installed inside the steel casing, which can effectively protect the hydraulic jack 2 from the influence of the external environment. Especially in the environment of foundation pit construction, the steel casing can prevent water, soil or other materials from corroding and damaging the hydraulic jack 2.

[0100] The anti-fall steel beam 9 is a safety component in the overall structure of the hydraulic jack 2. Its main function is to prevent the hydraulic jack 2 from falling or shifting position during installation or operation. The anti-fall steel beam 9 is vertically welded to the top of the steel casing, ensuring a secure connection and the ability to withstand potential weight and external forces. The first and second ends of the anti-fall steel beam 9 are respectively suspended from the inner and outer walers of the concrete support beam 1. Through this structure, the anti-fall steel beam 9 firmly connects the hydraulic jack 2 to the concrete support beam. During the excavation of the foundation pit, due to complex ground conditions or drastic changes in the construction environment, the anti-fall steel beam 9 can prevent accidents and ensure that the hydraulic jack 2 maintains a stable working state.

[0101] Furthermore, the foundation pit deformation support system also includes:

[0102] 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.

[0103] The load-bearing steel plate 10 is a crucial component of the foundation pit deformation support system. Its primary function is to distribute the pressure from the piston end of the hydraulic jack 2 onto the concrete support beam 1, ensuring uniform pressure distribution and enhancing the stability of the support structure. The load-bearing steel plate 10 is embedded in the inner waler of the concrete support beam 1 and fixed within the concrete structure, ensuring it is not easily displaced or detached. The piston end of the hydraulic jack 2 presses against the load-bearing steel plate 10, which then evenly transmits this pressure to the concrete support beam 1. This effectively distributes the force applied by the hydraulic jack 2 across the entire concrete support beam 1, thereby reducing the risk of structural damage caused by excessive localized stress.

[0104] Furthermore, the strain gauge 3 is welded in series to the reserved position of the main reinforcing bar inside the concrete support beam 1.

[0105] Strain gauge 3 is welded in series to the reserved position of the main reinforcing bar inside the concrete support beam 1. The main reinforcing bar is the steel bar that bears most of the load in the concrete structure. It is usually located in the core area of ​​the structure. The reserved position is usually a stress concentration area considered in the design. The purpose of welding strain gauge 3 is to directly sense the stress change in this stress concentration area. At this reserved position, the deformation of the concrete support beam 1 is the most significant. Therefore, strain gauge 3 can accurately reflect the deformation that occurs in the foundation pit during construction.

[0106] In summary, any of the methods or steps described above can be stored as computer instructions or programs in various types of computer memory, and the computer instructions or programs can be recognized by various types of computer processors to implement any of the above methods or steps.

[0107] Based on the above specific embodiments of the present invention, any improvements and modifications made to the present invention by those skilled in the art without departing from the principle of the present invention shall fall within the patent protection scope of the present invention.

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. 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. 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.

2. The method for controlling foundation pit deformation 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 features, deformation period term features, and deformation residual term features. 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 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.

5. 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 1-4, 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.

6. The foundation pit deformation control system as described in claim 5, 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).

7. The foundation pit deformation control system as described in claim 5, 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).

8. The foundation pit deformation control system as described in claim 5, 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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