Intelligent sensing and pressure self-adaption support pile system

Abstract

The intelligent sensing and pressure self-adaption support pile system comprises a plurality of support pile bodies, a sensor network, a hydraulic servo adjusting system and an intelligent control unit. The support pile body is of a conventional foundation pit support pile structure, is prefabricated by reinforced concrete or is formed by cast-in-place, provides a basic support function and resists soil pressure; the sensor network is embedded into the support pile body and monitors the strain condition of each pile body in real time; the intelligent control unit calculates support parameters according to monitoring data of the sensor network and outputs a control instruction; and the hydraulic servo adjusting system automatically adjusts the contact pressure between the pile and the soil according to the control instruction. The system can monitor the stress state of a pile body in real time and automatically adjust supporting parameters through the hydraulic servo system, so that the safety and reliability of foundation pit engineering are remarkably improved.

Description

Technical Field

[0001] This invention belongs to the field of geotechnical engineering technology and relates to an intelligent sensing and pressure adaptive support pile system. Background Technology

[0002] With the continuous development of urban underground space, deep foundation pit projects are showing a significant trend of continuous expansion in scale and increasingly complex surrounding environment, which puts forward higher requirements for the safety and adaptability of foundation pit support structures.

[0003] Currently widely used traditional foundation pit support piles are mostly rigid structures, whose support characteristics remain fixed after installation. Their core drawback is their inability to adaptively adjust to the dynamic changes in soil pressure during foundation pit excavation. Taking the support pile device provided by the existing technology CN214033731U as an example, although this device can adapt to piles of different diameters, it lacks a mechanism for real-time monitoring of the pile's stress state and does not possess the ability to adjust to changes in soil pressure. In deep foundation pit construction, as the excavation depth increases, the redistribution of soil stress can easily lead to displacement or cracking of the support piles, posing significant safety hazards. Simultaneously, traditional support structures are prone to damage due to overload when soil pressure increases abnormally, while failing to fully utilize their support potential when pressure decreases, resulting in wasted performance.

[0004] In recent years, some advanced support technologies have attempted to incorporate monitoring elements, but most solutions remain at the passive monitoring level and have not yet formed a systematic solution integrating "monitoring-decision-active adjustment." For example, the "adaptive support column based on multimodal perception" proposed in patent CN120626219A focuses on the adaptive bearing cap of the space requiring support, rather than the stress adjustment of the foundation pit support piles. The "intelligent square pile reflecting real-time bearing capacity" involved in CN220150368U can only monitor the pressure and tension exerted by the pile cap on the square pile, and cannot actively intervene in the pressure distribution at the contact surface between the pile and the soil. In summary, existing technologies still have significant shortcomings in terms of system integration and dynamic adaptive capabilities for foundation pit support piles, making it difficult to meet the safety and efficiency requirements of complex deep foundation pit engineering. Summary of the Invention

[0005] The purpose of this invention is to provide an intelligent sensing and pressure-adaptive support pile system, which solves the defect in the existing technology that the support pile cannot adaptively adjust according to the dynamic changes in soil pressure, and realizes the transformation of the support pile from passive support to active adaptation.

[0006] This invention provides an intelligent sensing and pressure adaptive support pile system, comprising: multiple support pile bodies, a sensor network, a hydraulic servo adjustment system, and an intelligent control unit;

[0007] The support pile body is a conventional foundation pit support pile structure, which is made of precast reinforced concrete or cast on site, providing basic support function and resisting soil pressure.

[0008] The sensor network is embedded inside the support pile body to monitor the strain of each pile body in real time.

[0009] The intelligent control unit calculates support parameters based on monitoring data from the sensor network and outputs control commands.

[0010] The hydraulic servo adjustment system automatically adjusts the contact pressure between the pile and the soil according to control commands.

[0011] The intelligent sensing and pressure-adaptive support pile system of the present invention has the following beneficial effects:

[0012] (1) This invention uses an optical fiber sensor network embedded in the pile body to monitor the pile strain and tilt angle in real time, forming a comprehensive pile body status perception capability.

[0013] (2) The system of the present invention adopts a hydraulic servo system, which dynamically adjusts the pressure distribution of the pile-soil contact surface according to the monitoring data, so as to realize the transformation from passive support to active adaptation. The hydraulic servo adjustment system adopts a distributed layout, and multiple hydraulic bladder pressure chambers can be controlled independently to realize precise pressure adjustment of the pile-soil contact surface.

[0014] (3) The intelligent control unit of the present invention has a built-in dedicated algorithm that can predict the trend of earth pressure change based on real-time monitoring data and perform pre-adjustment to improve the system's response speed and control accuracy.

[0015] (4) The system of the present invention integrates perception, decision-making and execution functions into one, forming a complete closed-loop control system, which significantly improves the intelligence level of the support system. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the cross-section of the adaptive support pile system of the present invention adapted to the support pile-support foundation pit;

[0017] Figure 2 This is a schematic diagram of the cross-section of the adaptive support pile system of the present invention adapted to the support pile-anchor cable foundation pit;

[0018] Figure 3 This is a schematic diagram of the adaptive support pile system of the present invention adapted to the support pile-support foundation pit.

[0019] Figure 4 This is a schematic diagram of the adaptive support pile system of the present invention adapted to the support pile-anchor cable foundation pit.

[0020] Figure 5 This is a schematic diagram of the fiber optic sensor deployment for the support piles;

[0021] 1-Support pile body, 2-Fiber optic sensor, 3-Hydraulic bladder pressure chamber, 4-Hydraulic pump station, 5-Hydraulic pipeline, 6-Steel support, 7-Anchor cable. Detailed Implementation

[0022] The present invention provides an intelligent sensing and pressure adaptive support pile system, comprising: multiple support pile bodies 1, a sensor network, a hydraulic servo adjustment system, and an intelligent control unit.

[0023] The support pile body 1 is a conventional foundation pit support pile structure, made of precast reinforced concrete or cast in place, providing basic support functions and resisting soil pressure. The sensor network is embedded inside the support pile body to monitor the strain of each pile in real time. The intelligent control unit calculates support parameters based on the monitoring data from the sensor network and outputs control commands. The hydraulic servo adjustment system automatically adjusts the contact pressure between the pile and the soil according to the control commands.

[0024] like Figures 1 to 5 As shown, the sensor network consists of multiple fiber optic sensors 2, which are pre-embedded in the reinforcing cage of the support pile body 1 during the prefabrication process. The fiber optic sensors 2 are vertically fixed along the direction of the main reinforcing bars of the reinforcing cage using cable ties and epoxy resin adhesive dots to ensure that the fiber optic sensors deform synchronously with the pile body and monitor the changes in pile strain and tilt angle in real time. The fiber optic sensors 2 are arranged in a U-shape, with one side located in the tension zone and the other side located in the compression zone.

[0025] The hydraulic servo adjustment system includes: multiple hydraulic bladder-type pressure chambers 3, a hydraulic pump station 4, a control valve group, and hydraulic pipelines 5. The multiple hydraulic bladder-type pressure chambers 3 are arranged at the pile-soil contact surface, and the pile-soil contact surface is divided into multiple monitoring units vertically according to the arrangement of the hydraulic bladder-type pressure chambers 3. Each hydraulic bladder-type pressure chamber 3 is correspondingly set with a support point of the steel support 6 or an anchor point of the anchor cable 7.

[0026] The hydraulic bladder-type pressure chamber 3 is connected to the hydraulic pump station 4 via hydraulic pipeline 5. The hydraulic pump station 4, according to the control commands of the intelligent control unit, adjusts the pressure of the corresponding hydraulic bladder-type pressure chamber through the control valve group, thereby changing the pressure distribution at the pile-soil contact surface. The intelligent control unit and the hydraulic pump station 4 are integrated into a control center located on the ground. The control center should be located at an appropriate distance from the foundation pit to avoid construction interference and ensure the safety of operators.

[0027] The hydraulic bladder pressure chamber is fixed to the reinforcing cage by concrete protective blocks to ensure that it is located at the pile-soil contact surface later. When the concrete of the support pile body has initially set but has not yet formed strength, hydraulic oil of a certain pressure is pumped into the hydraulic bladder pressure chamber through the hydraulic pump station to put the hydraulic bladder pressure chamber into working state. When the concrete of the support pile body reaches the design strength, the hydraulic pump station is adjusted so that the pressure in the hydraulic bladder pressure chamber is the static earth pressure value at its working position. The static earth pressure value is calculated according to the soil type and parameters in the site survey report.

[0028] The intelligent control unit includes a data acquisition module, a data processing module, and a control command output module. The data acquisition module is responsible for acquiring data monitored by the sensor network. The data processing module is responsible for calculating the strain and additional pressure of each monitoring unit and determining the safety status of each support pile. The control command output module generates a control command when the data processing module determines that the support pile needs pressure adjustment; that is, it sends the additional pressure to the hydraulic servo adjustment system to adjust the contact pressure between the pile and the soil.

[0029] In practice, the data processing module calculates the strain and additional pressure of each monitoring unit according to the following formula:

[0030]

[0031] in, The strain experienced by the optical fiber; Brillouin shift, which is the frequency difference between the scattered light and the incident light, in MHz; The current ambient temperature; This is the reference temperature, i.e., the baseline temperature used during laboratory calibration. The Brillouin frequency shift under reference conditions; The strain sensitivity coefficient; This is the temperature sensitivity coefficient.

[0032] After obtaining the strain data, the strain data is integrated along the pile height direction to calculate the deflection w and the strain of the i-th monitoring unit. Then, calculate the additional pressure required for each monitoring unit according to the following formula:

[0033]

[0034] in, This is the coefficient of lateral pressure on the soil. The area of ​​the monitoring unit; Let be the target strain of the i-th monitoring unit, for example, a value of 0.5. .

[0035] In practice, the data processing module determines the safety status of each support pile body based on the following conditions:

[0036] when At the same time, maintain the current support parameters. This represents the yield strain of the concrete.

[0037] when If the displacement rate dw / dt > 2 mm / h, an early warning will be triggered, and the optimization of design and construction parameters will be initiated.

[0038] when If the displacement changes abruptly by Δw > 5mm, the system will enter voltage regulation mode and trigger an alarm.

[0039] In specific implementation, the data processing module can also use an LSTM neural network to predict the displacement trend in the next 30 minutes based on historical data, thereby improving the system's adaptability; the historical data includes the strain of the support pile body, the displacement of the soil, and the soil pressure.

[0040] In practice, the system also includes a human-machine interface that displays the stress state and adjustment process of the support piles in real time and supports manual intervention.

[0041] In practical applications, after installing the fiber optic sensor 2 and the hydraulic bladder pressure chamber 3, connect the sensor data cable and hydraulic pipeline to the ground control center. After powering on, perform a system self-test to confirm that all sensors and data transmission channels are working properly. Then, input the basic engineering parameters and support safety threshold, and start the intelligent algorithm for initialization settings. During system trial operation, gradually adjust the control parameters to optimize the system response characteristics. During the excavation of the foundation pit, the system maintains 24 / 7 operation, monitors the changes in internal forces of the support piles in real time, and connects the data to the automated monitoring platform. It automatically adjusts according to the preset algorithm and preset construction sequence. During construction, the system is regularly maintained and inspected, including sensor sensitivity calibration, hydraulic system oil level and pressure checks, etc. When the monitoring data indicates that the stress at a certain point in the pile body is close to the critical value, the hydraulic bladder pressure chamber at the corresponding location is activated. By injecting or discharging hydraulic oil, the local contact pressure is changed, thereby optimizing the distribution of internal forces in the pile body and avoiding structural damage. If an abnormality is detected, the system will issue an alarm and indicate the fault point, facilitating timely handling by technicians.

[0042] This invention discloses an intelligent sensing and pressure-adaptive support pile system. Through a multimodal sensing system, an adaptive pressure adjustment mechanism, and an intelligent decision-making algorithm, it overcomes the shortcomings of existing technologies where support piles cannot adaptively adjust to dynamic changes in soil pressure. This achieves a transformation of the support pile from passive support to active adaptation. The system can monitor the stress state of the pile body in real time and automatically adjust support parameters through a hydraulic servo system, thereby significantly improving the safety and reliability of foundation pit engineering. This technology is particularly suitable for deep foundation pit engineering in complex geological conditions and sensitive surrounding environments. It can effectively reduce the risk of support structure failure, save engineering costs, and improve construction efficiency, demonstrating broad engineering application prospects and significant economic and social benefits.

[0043] The above description is only a preferred embodiment of the present invention and is not intended to limit the ideas of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A smart sensing and pressure adaptive support pile system, characterized in that, include: Multiple support pile bodies, sensor network, hydraulic servo adjustment system and intelligent control unit; The support pile body is a conventional foundation pit support pile structure, which is made of precast reinforced concrete or cast on site, providing basic support function and resisting soil pressure. The sensor network is embedded inside the support pile body to monitor the strain of each pile body in real time. The intelligent control unit calculates support parameters based on monitoring data from the sensor network and outputs control commands. The hydraulic servo adjustment system automatically adjusts the contact pressure between the pile and the soil according to control commands.

2. The intelligent sensing and pressure adaptive support pile system of claim 1, wherein, The sensor network consists of multiple fiber optic sensors, which are pre-embedded in the steel cage of the support pile body during the prefabrication process. The fiber optic sensors are vertically fixed along the direction of the main reinforcement bars of the steel cage using cable ties and epoxy resin adhesive dots, and are arranged in a U-shape. One side of the fiber optic sensor is located in the tension zone and the other side is located in the compression zone.

3. The intelligent sensing and pressure adaptive support pile system of claim 1, wherein, The hydraulic servo adjustment system includes: multiple hydraulic bladder pressure chambers, a hydraulic pump station, a control valve group, and hydraulic pipelines; multiple hydraulic bladder pressure chambers are set at the pile-soil contact surface, and the pile-soil contact surface is divided into multiple monitoring units in the vertical direction according to the arrangement of the hydraulic bladder pressure chambers; the hydraulic bladder pressure chambers are set one-to-one with the support points of the steel supports or the anchor points of the anchor cables. The hydraulic bladder-type pressure chamber is connected to the hydraulic pump station via hydraulic pipelines; the hydraulic pump station adjusts the pressure of the corresponding hydraulic bladder-type pressure chamber through the control valve group according to the control instructions of the intelligent control unit, thereby changing the pressure distribution of the pile-soil contact surface.

4. The intelligent sensing and pressure adaptive support pile system of claim 3, wherein, The hydraulic bladder pressure chamber is fixed to the reinforcing cage by a concrete protective block to ensure that it is located at the pile-soil contact surface in the later stage. When the concrete of the support pile body has initially set but has not yet reached its full strength, a certain pressure of hydraulic oil is pumped into the hydraulic bladder pressure chamber through the hydraulic pump station to put the hydraulic bladder pressure chamber into working condition. After the concrete of the support pile body reaches the design strength, the hydraulic pump station is adjusted so that the pressure in the hydraulic bladder pressure chamber is the static earth pressure value at its working position. The static earth pressure value is calculated based on the soil type and parameters in the site survey report.

5. The intelligent sensing and pressure adaptive support pile system of claim 4, wherein, The intelligent control unit includes: The data acquisition module is responsible for collecting data monitored by the sensor network; The data processing module is responsible for calculating the strain and additional pressure of each monitoring unit according to the following formulas: wherein, is the strain experienced by the optical fiber; is the Brillouin frequency shift, i.e. the difference in frequency between the scattered light and the incident light, in MHz; is the current ambient temperature; is the reference temperature, i.e. the reference temperature at the time of laboratory calibration; is the amount of Brillouin frequency shift in the reference state; is the strain sensitivity coefficient; is the temperature sensitivity coefficient; The strain data is integrated along the height of the pile to calculate the deflection w and the strain of the i-th monitoring unit The additional pressure required for each monitoring unit is then calculated according to the following equation: wherein, is the lateral earth pressure coefficient of the soil mass; is the area of the monitoring unit; is the target strain of the i-th monitoring unit; The data processing module determines the safety status of each support pile body based on the following conditions: When the current support parameters are maintained, is the concrete yield strain; When When the displacement rate dw / dt is greater than 2 mm / h, a pre-warning is initiated, and design and construction parameter optimization is initiated. When Or displacement mutation Δw> 5mm, into the pressure regulating state and alarm; The control command output module is used to generate a control command when the data processing module determines that the support pile body needs to be pressure adjusted, that is, to send the additional pressure to the hydraulic servo adjustment system to adjust the contact pressure between the pile and the soil.

6. The intelligent sensing and pressure-adaptive support pile system according to claim 5, characterized in that, The data processing module uses an LSTM neural network to predict the displacement trend for the next 30 minutes based on historical data, thereby improving the system's adaptability. The historical data includes the strain of the support pile body, the displacement of the soil, and the soil pressure.

7. The intelligent sensing and pressure-adaptive support pile system according to claim 1, characterized in that, The intelligent control unit is integrated with the hydraulic pump station and is located in the control center on the ground.

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