A method and system for controlling pipe pull-out of joints in ultra-deep seepage-proof walls

Abstract

This invention discloses a method and system for controlling the extraction of joint pipes in ultra-deep cutoff walls. By deploying a cluster of depth, temperature, pressure, and strain sensors on the inner wall of the joint pipe, data is collected in real time. The initial setting time of the concrete is first determined using the temperature inflection point method, and then the extraction time is determined using the pressure inflection point method, with dual verification ensuring accuracy. A depth-zoned multi-threshold control strategy is adopted, determining the corresponding extraction height based on the extraction time of each control zone. Combined with dynamically adjusted extraction speed, the extraction operation is cyclically monitored and executed until the pipe is completely extracted. This method comprehensively improves the quality, safety, and adaptability of ultra-deep cutoff wall joint pipe extraction construction, and is particularly suitable for cutoff wall projects under ultra-deep and complex geological conditions with extremely high construction precision requirements.

Description

Technical Field

[0001] This invention belongs to the field of construction technology of anti-seepage walls in water conservancy projects, and specifically relates to a method and system for controlling the pull-out of joint pipes in ultra-deep anti-seepage walls. Background Technology

[0002] In engineering, cutoff walls with a depth exceeding 100m are defined as ultra-deep cutoff walls. Each unit segment of the cutoff wall is connected by joints to form a whole, and these joints are the weakest points. If the joint design is inappropriate or the construction quality is poor, concentrated leakage may occur at certain joints, potentially leading to soil erosion behind the wall and even structural collapse. Therefore, selecting the appropriate joint type is a crucial technical issue in cutoff wall engineering. The "joint pipe method" is currently an advanced technology for joint treatment in cutoff wall construction and a key process for ensuring the seepage prevention effect and construction quality of the cutoff wall.

[0003] The pipe-pulling method, a low-cost, high-efficiency, and high-quality construction technique for cutoff wall joints, is widely used in cutoff wall construction. The key technology of this method lies in controlling the pipe-pulling strategy (pulling time and height). Current technology makes it difficult to accurately determine the timing of pipe extraction from the joint hole. Extracting it too early, when the concrete in the joint hole is still in a fluid state, can cause the joint hole to shrink or collapse. Extracting it too late, when the concrete bond strength is too high, makes the pipe difficult to extract or causes it to become stuck, thus affecting the normal construction of the diaphragm wall. Furthermore, even if the extraction timing is appropriate, if the bottommost pipe is buried too deep in the joint hole, it increases the difficulty of extraction. Therefore, in addition to accurately controlling the extraction time, it is also necessary to effectively monitor the pulling height of the bottommost pipe. Currently, control is mainly achieved through field tests and past engineering experience, which involves considerable arbitrariness and uncertainty. Summary of the Invention

[0004] To address the aforementioned shortcomings in existing technologies, the present invention provides a method and system for controlling the pull-out of joint pipes in ultra-deep cut-off walls. This method and system uses multiple sensors to monitor the concrete condition in real time and dynamically optimize the pull-out time and height of the joint pipes, thus solving the technical problem of joint pipes becoming stuck or concrete collapsing during the construction of ultra-deep cut-off walls (depth greater than 100m).

[0005] To achieve the aforementioned objectives, the technical solution adopted by this invention is: a method for controlling the pipe pull-out of an ultra-deep seepage-proof wall joint, comprising:

[0006] A sensor cluster, including depth sensors, temperature sensors, pressure sensors, and strain sensors, is installed on the inner wall of the seepage barrier joint pipe.

[0007] Based on the variation of collected temperature data over time, the initial setting time of concrete is determined by the temperature inflection point method.

[0008] Based on the determination of the initial setting time of concrete, and based on the variation of pressure data over time, the pull-out time of the joint pipe is determined by the pressure inflection method.

[0009] Based on the collected depth data, the pull-out height at the current joint pipe depth is determined by using a depth partitioning multi-threshold control strategy and combining the pull-out time of the joint pipe in the control section.

[0010] When the current working depth of the connector tube is greater than or equal to the current pulling height, the pulling operation of the connector tube is performed by dynamically adjusting the pulling speed.

[0011] The pulling height and pulling time of the joint pipe in the remaining control section are monitored cyclically until the joint pipe is completely pulled out.

[0012] Furthermore, based on temperature data collected by a single temperature sensor, the initial setting time of concrete is determined using the temperature inflection point method, including:

[0013] The collected temperature data is smoothed and filtered.

[0014] The temperature change rate was calculated using the central difference method for the temperature data after smoothing and filtering.

[0015] Within a preset search time window after pouring, the first local minimum point is searched sequentially along the time axis based on the temperature change rate, and this is taken as the initial setting time of the concrete.

[0016] Furthermore, the initial setting time of the concrete for:

[0017]

[0018] In the formula, The acceleration is the rate of temperature change, σ R This represents the standard deviation of the rate of temperature change after pouring within the preset search time range. This is the noise suppression coefficient. For noise, Adjust the offset for time.

[0019] Furthermore, the timing of pulling out the connector tube is determined, including:

[0020] When the concrete pouring of the outer wall of the joint pipe reaches the initial setting time of the concrete, and the collected pressure data is less than or equal to the preset pressure threshold, the corresponding time will be taken as the pull-out time of the joint pipe.

[0021] The preset pressure threshold is determined based on the minimum pressure value of the joint pipe during the process of transforming from plastic concrete to solid concrete after the initial setting of the concrete.

[0022] Further, determine the pull-out height of the connector tube, including:

[0023] The connector pipe is divided along the depth direction into: Each control section is divided into sections, and the pull-out time of the connector pipe in each control section is determined. ; where superscript For the control section number, ;

[0024] At any time t, it is determined that the following condition is met. Maximum control section number The calculated lifting height is the maximum control section number. Bottom depth , This indicates the length of a single connector pipe.

[0025] Furthermore, the joint pipe is divided into N control sections along the depth direction through a dynamic adjustment mechanism, and the division method is as follows:

[0026] The deep gradient partitioning method is adopted to divide the connector pipe into several primary control sections according to the total length of the connector pipe. Within each primary control section, several secondary control sections are divided according to the length of a single connector pipe.

[0027] Continuously monitor the formation pressure change rate in each secondary control section and determine whether the formation pressure change rate in the current secondary control section or its adjacent secondary control section exceeds the set threshold.

[0028] If so, the control segment partitioning and reorganization will be triggered to form a new control segment division strategy and determine the take-off time and take-off height corresponding to each secondary control segment.

[0029] If not, then determine the take-off time and take-off height corresponding to each secondary control section according to the current control section division strategy.

[0030] Furthermore, the pulling operation of the connector tube is performed by dynamically adjusting the pulling speed, including:

[0031] Set the foundation lifting speed according to the control section where the current lifting height is located. ;

[0032] Based on the strain data of the control section at the current extraction height, calculate the current actual tube extraction resistance. ;

[0033] Based on the pressure data of the control section at the current extraction height, calculate the formation pressure change rate of the corresponding control section. ;

[0034] Calculate the current extraction speed based on the basic extraction speed, the current actual extraction resistance, and the formation pressure change rate. ,in, This represents the resistance adjustment coefficient. This indicates the preset safe tube removal resistance threshold. , Indicates the adjustment factor;

[0035] Based on the calculated current pulling speed, perform the pulling operation of the connector tube.

[0036] A pipe-pulling control system for ultra-deep seepage-proof wall joints includes:

[0037] Data acquisition module: used to collect monitoring data of the connector pipe through a cluster of sensors deployed on the inner wall of the connector pipe, including temperature data, height data, pressure data and strain data;

[0038] Joint pipe segmentation module: used to divide the joint pipe into several control sections along the depth direction according to the length of a single joint pipe;

[0039] Pull-out time monitoring module: used to determine the pull-out time of different control sections based on the temperature inflection point method and the pressure inflection point method;

[0040] Pull-out height monitoring module: used to determine the pull-out height at the current joint pipe depth based on the maximum control section number and the length of the control section that meets the pull-out time requirement;

[0041] Pulling speed adjustment module: used to determine the current pulling speed of the joint pipe based on the actual pipe pulling resistance and formation pressure change rate of the control section where the current pulling height is located;

[0042] Tube pulling execution module: Used to perform the tube pulling operation according to the current pulling speed when the current working depth of the tube is greater than or equal to the current pulling height.

[0043] Furthermore, the pull-out time monitoring module includes:

[0044] Initial setting time determination unit: Used to search for the first local minimum point of the temperature change rate of all temperature data in the control section along the time axis within a time window of the preset search time range after pouring, and use it as the initial setting time of concrete.

[0045] Pull-out time determination unit: Based on the initial setting time of concrete, when the collected pressure data is less than or equal to the preset pressure threshold, the corresponding time is used as the pull-out time of the joint pipe control section.

[0046] Furthermore, in the lifting height monitoring module, at any time t, it is determined that the following conditions are met. Maximum control section number The calculated lifting height is the maximum control section number. Bottom depth , This indicates the length of a single connector pipe.

[0047] This invention's method, through a combined strategy of "precise time judgment + refined process control + real-time dynamic monitoring," comprehensively improves the quality, safety, and adaptability of ultra-deep cutoff wall joint pipe extraction construction. It is particularly suitable for cutoff wall projects in ultra-deep, complex geological conditions where extremely high construction precision is required. Specific beneficial effects include:

[0048] (1) Accurately control key time nodes to improve construction quality:

[0049] This invention utilizes temperature sensors to collect data and determines the initial setting time of concrete using the temperature inflection point method. Compared to traditional experience-based judgments (such as relying on touch or observation), this method more objectively and accurately captures the critical state of concrete from plasticity to initial hardening, providing a reliable time reference for subsequent pull-out operations. This avoids problems such as wall cracking and poor joint sealing caused by judging the initial setting time too early or too late. Based on the initial setting time, the pull-out time is determined by combining pressure sensor data with the pressure inflection method, further considering the changes in the force between the concrete and the joint pipe. When a significant inflection occurs in the pressure, it indicates that the concrete strength is sufficient to support the wall structure, and the adhesion between the joint pipe and the concrete is within the appropriate range for pull-out, minimizing disturbance to the wall during pull-out.

[0050] (2) Refined control of the extraction process to ensure the integrity of the wall:

[0051] Based on depth sensor data, a multi-threshold control strategy is formulated according to depth zones, and the corresponding extraction height is determined by combining the extraction time of each zone. The concrete setting rate and stress state of ultra-deep cutoff walls vary at different depths (e.g., the influence of water pressure and temperature is more complex at deeper depths). Zoned control can adapt to the construction needs of different depths and avoid problems such as excessive local stress or insufficient extraction that may be caused by extraction at a uniform height.

[0052] The extraction speed is dynamically adjusted based on the relationship between the working depth of the joint pipe and the current extraction height, as monitored in real time. When the depth changes, the speed is adjusted accordingly (for example, a slower speed may be needed for deeper layers to balance water pressure and bonding force), which can reduce the pulling force on the surrounding concrete during extraction and reduce the probability of defects such as wall deformation and honeycomb surface.

[0053] (3) Real-time monitoring and closed-loop control enhance construction safety and controllability:

[0054] By using a multi-sensor cluster for collaborative monitoring, integrating depth, temperature, pressure, and strain sensors to form a monitoring network, it can acquire key information such as the location of the joint pipe, changes in concrete temperature, and the stress and deformation state of the pipe body in real time. This enables comprehensive dynamic monitoring of the pipe pulling process and timely detection of abnormalities (such as excessive strain which may indicate that the pipe body is about to be damaged, or sudden pressure changes which may indicate concrete defects).

[0055] By cyclically monitoring the extraction height and time of the remaining sections, a closed-loop process of "monitoring-judgment-control-re-monitoring" is formed to ensure that each construction stage is under control. Even in the event of emergencies (such as abnormal local concrete setting speed), subsequent operations can be quickly adjusted through real-time data feedback to prevent the problem from escalating and improve the safety of ultra-deep cutoff wall construction.

[0056] (4) Reduce human error and achieve intelligent construction:

[0057] Traditional pipe pulling operations rely on human experience, which is highly subjective and prone to errors (e.g., different workers may have significantly different judgments on the "appropriate pulling time"). This invention significantly reduces human interference by using sensor data-driven automated judgment (temperature inflection point, pressure inflection point) and parameter control (pulling height, speed), promoting the transformation of the construction process towards intelligence and standardization, and improving construction efficiency and consistency. Attached Figure Description

[0058] Figure 1 The flowchart of the pipe pulling control method for ultra-deep seepage barrier wall joints provided by the present invention.

[0059] Figure 2 This is a schematic diagram of the joint pipe to be pulled out before the initial setting of concrete provided by the present invention.

[0060] Figure 3 This is a schematic diagram illustrating the changes in concrete temperature and temperature change rate within the hole during the concrete pouring process, provided by the present invention.

[0061] Figure 4 This is a schematic diagram illustrating the pressure changes in the joint pipe during the concrete pouring process provided by the present invention. Detailed Implementation

[0062] The specific embodiments of the present invention are described below to enable those skilled in the art to understand the present invention. However, it should be understood that the present invention is not limited to the scope of the specific embodiments. For those skilled in the art, various changes are obvious as long as they are within the spirit and scope of the present invention as defined and determined by the appended claims. All inventions utilizing the concept of the present invention are protected.

[0063] This invention provides a method for controlling the removal of pipes from joints in ultra-deep seepage-proof walls, such as... Figure 1As shown, it includes:

[0064] A sensor cluster, including depth sensors, temperature sensors, pressure sensors, and strain sensors, is installed on the inner wall of the seepage barrier joint pipe.

[0065] Based on the variation of collected temperature data over time, the initial setting time of concrete is determined by the temperature inflection point method.

[0066] Based on the determination of the initial setting time of concrete, and based on the variation of pressure data over time, the pull-out time of the joint pipe is determined by the pressure inflection method.

[0067] Based on the collected depth data, the pull-out height at the current joint pipe depth is determined by using a depth partitioning multi-threshold control strategy combined with the pull-out time of the joint pipe in each control section.

[0068] When the current working depth of the connector tube is greater than or equal to the current pulling height, the pulling operation of the connector tube is performed by dynamically adjusting the pulling speed.

[0069] The pulling height and pulling time of the joint pipe in the remaining control section are monitored cyclically until the joint pipe is completely pulled out.

[0070] In this embodiment of the invention, a sensor cluster is installed every 0.8 meters along the inner wall of the spliced ​​joint pipe (taking a single joint pipe length of 5m as an example). The sensor cluster includes depth sensors, temperature sensors, pressure sensors, and strain sensors. The sensor cluster collects important construction information such as depth, temperature, pressure, and strain in real time during the construction process. The collected data is transmitted to the established real-time intelligent monitoring system for the pipe pulling process of the anti-seepage wall joint pipe via a wireless network. This enables remote real-time monitoring of the pipe pulling process, facilitating construction managers to dynamically optimize and adjust the actual pipe pulling process.

[0071] Ultra-deep cutoff walls can be buried at depths of over 200 meters. Joint pipes need to be installed into the joint holes before the wall is poured. Due to the depth of the joint holes, multiple joint pipes are generally required to be connected and spliced ​​along their length. Each joint pipe is approximately 5 meters long. Figure 2 As shown, a series of sensor devices, including depth sensors, temperature sensors, and pressure sensors, are arranged sequentially along the depth direction on the inner wall of the connector pipe at intervals of 0.8m. By monitoring the data obtained from different sensors at the same elevation, the time for pipe removal can be determined; by monitoring the data obtained from sensors at different elevations, the height of pipe removal can be determined.

[0072] The key parameters collected on-site during the pipe pulling process mainly include the following:

[0073] Removal time: The removal time allows us to observe the changes in temperature, pressure, and strain over time, as well as to obtain the removal rate.

[0074] Real-time working depth: By recording the working depth of the tube being pulled out in real time, the position of the connector tube can be monitored and used as an indicator.

[0075] Temperature: The temperature sensor acquires the working temperature data of the inner wall of the joint pipe in real time. This parameter can be used to monitor the solidification state of the wall concrete and provide a basis for determining the joint pipe extraction time and depth.

[0076] Pressure: The pressure sensor acquires real-time pressure data of the inner wall of the connector pipe. This parameter can be used to monitor the solidification state of the concrete wall and provide a basis for determining the time and depth of the connector pipe pull-out.

[0077] In this embodiment of the invention, the initial setting time of concrete is determined by collecting temperature data from a single temperature sensor and using the temperature inflection point method, including:

[0078] The collected temperature data is smoothed and filtered.

[0079] The temperature change rate was calculated using the central difference method for the temperature data after smoothing and filtering.

[0080] Within a preset search time window after pouring, the first local minimum point is searched sequentially along the time axis based on the temperature change rate, and this is taken as the initial setting time of the concrete.

[0081] Specifically, in this embodiment, the concrete is in a multi-field coupled environment of hydration, temperature, and constraint from the moment it is poured. Therefore, directly using the setting time results tested under single-factor, standard conditions in the laboratory cannot adequately meet the needs of actual engineering construction. The temperature development process of concrete is influenced by its own factors such as mix proportions and surrounding heat dissipation conditions such as formwork type, structural form and thickness, and construction season.

[0082] like Figure 3 As shown, during the concrete pouring process, temperature changes in the concrete within the joint holes are monitored in real time using temperature sensors. The curve exhibits a clear inflection point. In the initial period after concrete pouring, the temperature may decrease slightly due to contact with the cooler ground or formwork, and the temperature increase is slow or negligible for a period. After a certain time, it increases rapidly. The driving force behind the temperature increase at the concrete measuring points comes from the heat released during cement hydration. During this process, the concrete transitions from the plastic stage to the hardening stage as the structure forms. Considering the slow hydration reaction rate before setting, the corresponding temperature rise driven by the heat released during hydration is relatively weak. As the hydration reaction enters the accelerated phase, it begins to release heat rapidly, leading to a rapid temperature rise, and the concrete structure is formed accordingly. Therefore, the early temperature development process of structural concrete can reflect the setting time of the wall concrete structure.

[0083] Because the hydration reaction of concrete is slow before initial setting, the rate of temperature change is low; after initial setting begins, the hydration reaction accelerates, and the rate of temperature change increases significantly. Therefore, the first minimum point of the rate of temperature change (the amount of temperature change per unit time) corresponds to the starting moment of the accelerated hydration reaction of concrete, i.e., the initial setting time of concrete.

[0084] In this embodiment, taking a preset search time range of 30 minutes to 14 hours after pouring as an example, the steps for determining the initial setting time of concrete include:

[0085] The collected temperature data is smoothed and filtered to eliminate noise interference;

[0086] Calculation of temperature change rate using the central difference method for:

[0087]

[0088] In the formula, Δt is the sampling time interval, and T(t+Δt) is the temperature at time t+Δt;

[0089] Within a time window from 30 minutes after pouring to a preset search deadline (e.g., 14 hours), sequentially search along the time axis for the first local minimum point that satisfies the following formula to obtain the initial setting time of the concrete. for:

[0090]

[0091] In the formula, The acceleration is the rate of temperature change, σ R The standard deviation of the temperature change rate after pouring within a preset search time range characterizes the intensity of environmental noise (such as sensor fluctuations and pouring disturbances). The noise suppression factor (taken as 0.25) is determined through engineering calibration. For noise, This is a time correction offset used to compensate for noise interference in locating the minimum of the second derivative. When the noise is high, the minimum point of the second derivative may deviate from the true initial condensation point due to noise fluctuations; in this case, the compensation amount is increased. This can prevent premature disconnection. When the noise level is low, the compensation amount can be ignored, and the system can directly rely on inflection point detection.

[0092] The relationship between the temperature change rate and the initial freezing state obtained based on the above method is shown in Table 1.

[0093] Table 1: Correspondence between temperature change rate and initial freezing state

[0094]

[0095] The method for determining the initial setting time of concrete provided in this embodiment ensures that the noise accurately represents the intensity of environmental interference by limiting the noise statistics window, so that the error of the calculated initial setting time is controlled within ±5%.

[0096] In this embodiment of the invention, based on the initial setting time of the concrete, the pull-out time of the joint pipe is determined according to the pressure change monitored by the pressure sensor.

[0097] In this embodiment, as Figure 4 As shown, with the increase of the pouring height, the lateral pressure monitored by the pressure sensor on the inner wall of the joint pipe also shows an increasing trend, and the lateral pressure has a linear relationship with the pouring height. At the beginning of the pouring process, the concrete is completely in a plastic fluid state. Due to gravity, the concrete deformation exhibits two states: vertical settlement and lateral expansion. As the concrete expands, the lateral pressure on the joint pipe gradually increases. During the period from pouring to initial setting, the plastic fluid gradually transforms into a plastic state, and the lateral pressure monitored on the inner wall of the joint pipe begins to decrease. After initial setting, the concrete loses its plastic fluid state. Due to the influence of temperature, the concrete expands, causing the lateral pressure on the inner wall of the joint pipe to increase again. This is because after initial setting, the concrete loses its plastic fluid state and transforms into a solid state. At this time, the temperature begins to cause the concrete to expand, resulting in the formwork lateral pressure increasing again with the rise in temperature, and the lateral pressure on the inner wall of the joint pipe also increases accordingly.

[0098] After the initial setting of concrete, the expansion caused by the heat of hydration leads to a renewed increase in the lateral pressure on the joint pipe after the concrete pouring is completed. Therefore, in this embodiment, the joint pipe pull-out time is determined as follows:

[0099] When the concrete pouring of the outer wall of the joint pipe reaches the initial setting time of the concrete, and the collected pressure data is less than or equal to the preset pressure threshold, the corresponding time will be taken as the pull-out time of the joint pipe.

[0100] The preset pressure threshold is determined based on the minimum pressure value of the joint pipe during the process of transforming from plastic concrete to solid concrete after the initial setting of the concrete.

[0101] In this embodiment of the invention, determining the extraction height is equally crucial after determining the extraction time. Ultra-deep cutoff walls have significant depths, and the concrete setting rate varies at different depths. The concrete at the bottom sets more slowly due to higher ground temperature and pressure. Because the concrete setting conditions vary significantly along the depth direction of the ultra-deep cutoff wall, using a uniform extraction time cannot guarantee the safe extraction of the bottom joint pipe. Therefore, it is necessary to adjust the extraction timing of joint pipes at different depths according to the depth differences.

[0102] This embodiment proposes a depth-partitioned multi-threshold control strategy to determine the pull-out height of the connector tube, including:

[0103] The connector pipe is divided along the depth direction into: Each control section is divided into sections, and the pull-out time of the connector pipe in each control section is determined. ; where superscript For the control section number, ;

[0104] At any time t, it is determined that the following condition is met. Maximum control section number The calculated lifting height is the maximum control section number. Bottom depth , This indicates the length of a single connector pipe.

[0105] In this embodiment, the connector pipe is divided into N control sections along the depth direction using a dynamic adjustment mechanism. The division method is as follows:

[0106] The deep gradient partitioning method is adopted to divide the connector pipe into several primary control sections according to the total length of the connector pipe. Within each primary control section, several secondary control sections are divided according to the length of a single connector pipe.

[0107] Continuously monitor the formation pressure change rate in each secondary control section and determine whether the formation pressure change rate in the current secondary control section or its adjacent secondary control section exceeds the set threshold.

[0108] If so, the control segment partitioning and reorganization will be triggered to form a new control segment division strategy and determine the take-off time and take-off height corresponding to each secondary control segment.

[0109] If not, then determine the take-off time and take-off height corresponding to each secondary control section according to the current control section division strategy.

[0110] For example, when the connector pipe is an ultra-deep connector pipe with a length greater than 50 meters, the connector pipe is divided into three primary control sections along the depth direction: shallow control section (0-20m), middle control section (20-40m), and deep control section (greater than 40m). Within each primary control section, it is further subdivided into multiple secondary control sub-segments according to the length of a single connector pipe. Each secondary segment independently performs sensor data analysis to determine the extraction time and extraction height.

[0111] During the monitoring of formation pressure change rates within each secondary control section, if the formation pressure change rate of a certain secondary control section or its adjacent secondary control section exceeds a set threshold, it indicates that a confined aquifer or significant formation change may be encountered, requiring a re-division of control sections. When reorganizing control sections to form a new control section division strategy, affected adjacent secondary control sections can be merged to form a new, larger temporary control section for unified pull-out judgment; alternatively, a single secondary control section with an abnormally severe pressure gradient can be divided into smaller sub-control sections (e.g., 2.5m) for more refined control.

[0112] Therefore, in this embodiment, the determination of the start-up time and start-up height of the control section is based on the currently obtained refined control section division results (including secondary control sections, temporary control sections and / or sub-control sections).

[0113] In this embodiment, taking a control section as a secondary control section as an example, the length of the control section is the length of a single connector pipe. Within each control section, the initial setting time is calculated based on multiple temperature sensors arranged in that section (one every 0.8m, approximately 6 per section). To avoid requiring more than half of the sensors in the section to detect the initial setting signal (i.e., the temperature change rate to reach a minimum) before considering the section to have reached initial setting, the starting time for pulling out the connector pipe in each control section is determined. include:

[0114] When the initial setting time of concrete can be detected based on the temperature data collected by at least half of the temperature sensors in the control section, the median of all the initial setting times of concrete is taken as the initial setting time of concrete in the corresponding control section.

[0115] Based on the initial setting time of concrete, when the pressure data collected by at least half of the pressure sensors in the control section is less than or equal to the preset pressure threshold, the corresponding time will be used as the pull-out time of the joint pipe in the current control section.

[0116] In this embodiment, after determining the pull-out height, when the real-time monitored working depth of the connector tube is greater than or equal to the current pull-out height, the pull-out operation of the connector tube is initiated, raising it to the pull-out height H. allow (t) and above.

[0117] In this embodiment of the invention, the pulling operation of the connector tube is performed by dynamically adjusting the pulling speed, including:

[0118] Set the foundation lifting speed according to the control section where the current lifting height is located. ;

[0119] Based on the strain data of the control section at the current extraction height, calculate the current actual tube extraction resistance. ;

[0120] Based on the pressure data of the control section at the current extraction height, calculate the formation pressure change rate of the corresponding control section. ;

[0121] Calculate the current extraction speed based on the basic extraction speed, the current actual extraction resistance, and the formation pressure change rate. ,in, This represents the resistance adjustment coefficient. This indicates the preset safe tube removal resistance threshold. , Indicates the adjustment factor;

[0122] Based on the calculated current pulling speed, perform the pulling operation of the connector tube.

[0123] For example, the base lifting speed in the control section where the current lifting height is set. When the control section is a shallow control section (0-20m), When the control section is the central control section, When the control segment is a depth control segment, Considering that the greater the depth, the greater the influence of ground pressure and concrete setting conditions, and the higher the risk of extraction, therefore, a setting is implemented. .

[0124] In this embodiment, based on During the calculation of the pulling speed, when the actual pulling resistance is... Approximately the preset safe tube removal resistance hour, If the value is significantly less than 1, the pull-out speed needs to be forcibly reduced. hour, ;when When it is very large, If the value is significantly less than 1, a forced reduction in the pull-out speed is required. When I was very young, Therefore, when the actual pipe pulling resistance exceeds the safety threshold or there is an abnormal sudden change in the formation pressure change rate, the pulling speed is automatically reduced or the pulling process is suspended.

[0125] It should be noted that during the extraction process, since the joint pipe is connected in sections, it may be necessary to disassemble the top joint pipe during lifting. Therefore, in actual operation, when a certain section meets the extraction conditions, the entire joint pipe is lifted until that section is completely detached from the concrete, and then the joint pipe corresponding to that section (i.e., the topmost section) is disassembled. Then, the initial setting time of each remaining joint pipe section is monitored, and the above process is repeated. This strategy ensures that each section is extracted promptly after its initial setting, avoiding the risks associated with cast pipe.

[0126] In this embodiment of the invention, based on the implementation process of the above-mentioned ultra-deep cutoff wall joint pipe pull-out control method, an ultra-deep cutoff wall joint pipe pull-out control system is also provided, comprising:

[0127] Data acquisition module: used to collect monitoring data of the connector pipe through a cluster of sensors deployed on the inner wall of the connector pipe, including temperature data, height data, pressure data and strain data;

[0128] Joint pipe segmentation module: used to divide the joint pipe into several control sections along the depth direction according to the length of a single joint pipe;

[0129] Pull-out time monitoring module: used to determine the pull-out time of different control sections based on the temperature inflection point method and the pressure inflection point method;

[0130] Pull-out height monitoring module: used to determine the pull-out height at the current joint pipe depth based on the maximum control section number and the length of the control section that meets the pull-out time requirement;

[0131] Pulling speed adjustment module: used to determine the current pulling speed of the joint pipe based on the actual pipe pulling resistance and formation pressure change rate of the control section where the current pulling height is located;

[0132] Tube pulling execution module: Used to perform the tube pulling operation according to the current pulling speed when the current working depth of the tube is greater than or equal to the current pulling height.

[0133] In this embodiment, the sensor cluster in the data acquisition module is arranged sequentially along the depth direction on the inner wall of the connector pipe at 0.8m intervals. By monitoring the data acquired by different sensors at the same elevation, the time for pipe removal can be determined, and by monitoring the data acquired by sensors at different elevations, the height of pipe removal can be determined.

[0134] In this embodiment, the joint pipe segmentation module can divide the control sections according to the working depth of the joint pipe and the length of a single joint pipe. For example, when the joint pipe is an ultra-deep joint pipe with a length greater than 50 meters, the joint pipe is divided into three primary control sections along the depth direction: shallow control section (0-20m), middle control section (20-40m), and deep control section (greater than 40m). Within each primary control section, it is further subdivided into multiple secondary control sub-segments according to the length of a single joint pipe. Each secondary segment independently performs sensor data analysis to determine the extraction time and extraction height.

[0135] During the monitoring of formation pressure change rates within each secondary control section, if the formation pressure change rate of a certain secondary control section or its adjacent secondary control section exceeds a set threshold, it indicates that a confined aquifer or significant formation change may be encountered, requiring a re-division of control sections. When reorganizing control sections to form a new control section division strategy, affected adjacent secondary control sections can be merged to form a new, larger temporary control section for unified pull-out judgment; alternatively, a single secondary control section with an abnormally severe pressure gradient can be divided into smaller sub-control sections (e.g., 2.5m) for more refined control.

[0136] In this embodiment, the start-up time monitoring module includes:

[0137] Initial setting time determination unit: Used to search for the first local minimum point of the temperature change rate of all temperature data in the control section along the time axis within a time window of the preset search time range after pouring, and use it as the initial setting time of concrete.

[0138] Pull-out time determination unit: Based on the initial setting time of concrete, when the collected pressure data is less than or equal to the preset pressure threshold, the corresponding time is used as the pull-out time of the joint pipe control section.

[0139] In this embodiment, the method by which the initial setting time determination unit determines the initial setting time of concrete is as follows:

[0140] The collected temperature data is smoothed and filtered.

[0141] The temperature change rate was calculated using the central difference method for the temperature data after smoothing and filtering.

[0142] Within a preset search time window after pouring, the first local minimum point is searched sequentially along the time axis based on the rate of temperature change, and this is taken as the initial setting time of the concrete. for:

[0143]

[0144] In the formula, The acceleration is the rate of temperature change, σ R This represents the standard deviation of the rate of temperature change after pouring within the preset search time range. This is the noise suppression coefficient. For noise, Adjust the offset for time.

[0145] In this embodiment, the method by which the start-up time determination unit determines the start-up time is as follows:

[0146] When the initial setting time of concrete can be detected based on the temperature data collected by at least half of the temperature sensors in the control section, the median of all the initial setting times of concrete is taken as the initial setting time of concrete in the corresponding control section.

[0147] Based on the initial setting time of concrete, when the pressure data collected by at least half of the pressure sensors in the control section is less than or equal to the preset pressure threshold, the corresponding time will be used as the pull-out time of the joint pipe in the current control section.

[0148] The preset pressure threshold is determined based on the minimum pressure value of the joint pipe during the process of transforming from plastic concrete to solid concrete after the initial setting of the concrete.

[0149] In this embodiment, in the lifting height monitoring module, at any time t, it is determined that the following conditions are met. Maximum control section number The calculated lifting height is the maximum control section number. Bottom depth , This indicates the length of a single connector pipe.

[0150] In this embodiment, in the tube pulling execution module, after determining the pulling time and pulling height, when the real-time monitored current working depth of the connector tube is greater than or equal to the current pulling height, the tube pulling operation is initiated, raising it to the pulling height H. allow (t) and above.

[0151] In this embodiment, the pulling operation of the connector tube is performed by dynamically adjusting the pulling speed, including:

[0152] Set the foundation lifting speed according to the control section where the current lifting height is located. ;

[0153] Based on the strain data of the control section at the current extraction height, calculate the current actual tube extraction resistance. ;

[0154] Based on the pressure data of the control section at the current extraction height, calculate the formation pressure change rate of the corresponding control section. ;

[0155] Calculate the current extraction speed based on the basic extraction speed, the current actual extraction resistance, and the formation pressure change rate. ,in, This represents the resistance adjustment coefficient. This indicates the preset safe tube removal resistance threshold. , Indicates the adjustment factor;

[0156] Based on the calculated current pulling speed, perform the pulling operation of the connector tube.

[0157] When performing pipe pulling operations based on the above-mentioned pulling time, pulling height, and pulling speed, if the actual pipe pulling resistance exceeds the safety threshold or the formation pressure change rate changes abnormally, the pulling speed will be automatically reduced or the pulling will be suspended.

[0158] During the extraction process, since the joint pipe is connected in segments, it may be necessary to disassemble the top joint pipe during lifting. Therefore, in practice, when a certain section meets the extraction conditions, the entire joint pipe is lifted until that section is completely detached from the concrete, and then the joint pipe corresponding to that section (i.e., the topmost segment) is disassembled. Then, the initial setting time of the remaining joint pipe segments is monitored, and the above process is repeated. This strategy ensures that each segment is extracted promptly after its initial setting, avoiding the risks associated with cast pipe.

[0159] Specific embodiments have been used to illustrate the principles and implementation methods of this invention. The descriptions of the embodiments above are only for the purpose of helping to understand the method and core ideas of this invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this invention. Therefore, the content of this specification should not be construed as a limitation of this invention.

[0160] Those skilled in the art will recognize that the embodiments described herein are intended to help the reader understand the principles of the invention, and should be understood that the scope of protection of the invention is not limited to such specific statements and embodiments. Those skilled in the art can make various other specific modifications and combinations based on the technical teachings disclosed in this invention without departing from the spirit of the invention, and these modifications and combinations are still within the scope of protection of this invention.

Claims

1. An ultra-deep cutoff wall joint pipe pulling control method, characterized by, The method comprises the following steps: Laying a sensor cluster on the inner wall of the cutoff wall joint pipe, including a depth sensor, a temperature sensor, a pressure sensor, and a strain sensor; Based on the change rule of the collected temperature data over time, the initial setting time of the concrete is determined by the temperature inflection point method; Based on the determination of the initial setting time of the concrete, based on the change rule of the collected pressure data over time, the pulling-up time of the joint pipe is determined by the pressure turning point method; Based on the collected depth data, the pulling-up height at the current joint pipe depth is determined by the depth partitioning multi-threshold control strategy combined with the pulling-up time of the control section joint pipe; When the real-time monitored current joint pipe working depth is greater than or equal to the current pulling-up height, the pulling-up operation of the joint pipe is performed by the dynamically adjusted pulling-up speed; The pulling-up height and the pulling-up time of the remaining control section joint pipe are monitored in a cycle until the joint pipe is pulled up; Based on the temperature data collected by a single temperature sensor, the initial setting time of the concrete is determined by the temperature inflection point method, which comprises the following steps: Smooth filtering processing is performed on the collected temperature data; The temperature change rate is calculated by the central difference method for the temperature data after the smooth filtering processing; In the time window of the preset search time range after pouring, the first local minimum value point is sequentially searched along the time axis based on the temperature change rate, which is taken as the initial setting time of the concrete; The pulling-up time of the joint pipe is determined, which comprises the following steps: When the joint pipe outer wall body concrete pouring reaches the initial setting time of the concrete, and the collected pressure data is less than or equal to the preset pressure threshold value, the corresponding time is taken as the pulling-up time of the joint pipe; The preset pressure threshold value is determined according to the minimum pressure value of the joint pipe in the process of converting the plastic state concrete into the solid state concrete after the initial setting of the concrete; The pulling-up height of the joint pipe is determined, which comprises the following steps: The joint pipe is divided into control sections along the depth direction, and the pull-up time of the joint pipe of each control section is determined ; wherein the superscript is the control section number, ; At any time t, the maximum control section number satisfying is determined The bottom depth of the pull-up height of the maximum control section number is calculated , denotes the length of a single joint pipe.

2. The ultra-deep cutoff wall joint pipe pulling control method according to claim 1, characterized by, The concrete initial setting time is: In the formula, is an acceleration of the temperature change rate, σ R is a standard deviation of the temperature change rate before a preset search time range after pouring, is a noise suppression coefficient, is noise, is a time correction offset.

3. The ultra-deep cutoff wall joint pipe pulling control method according to claim 1, characterized by, The joint pipe is divided into N control sections in the depth direction by a dynamic adjustment mechanism, and the division method is as follows: A depth gradient partitioning method is adopted, and the joint pipe is divided into a plurality of primary control sections according to the total length of the joint pipe, and in each primary control section, a plurality of secondary control sections are divided according to the length of a single joint pipe; The formation pressure change rate in each secondary control section is continuously monitored, and it is judged whether the formation pressure change rate of the current secondary control section or its adjacent secondary control section exceeds the set threshold value; If yes, the control section partitioning reorganization is triggered, a new control section division strategy is formed, and the pulling-up time and the pulling-up height corresponding to each secondary control section are determined; If no, the pulling-up time and the pulling-up height corresponding to each secondary control section are determined according to the current control section division strategy.

4. The ultra-deep cutoff wall joint pipe pulling control method according to claim 1, characterized by, The pulling-up operation of the joint pipe is performed by the dynamically adjusted pulling-up speed, which comprises the following steps: According to the control section in which the current lifting height is located, the basic lifting speed is set ; According to the strain data of the control section where the current pullout height is located, the current actual pipe-pulling resistance is calculated ; calculating a rate of change of formation pressure for the corresponding control section based on pressure data for the control section in which the current pull height resides ; According to the basic pulling speed, the current actual pipe-pulling resistance and the formation pressure change rate, the current pulling speed is calculated wherein, represents a resistance adjustment coefficient, represents a preset safe pipe-pulling resistance threshold, , represents an adjustment coefficient; The pulling-up operation of the joint pipe is performed according to the calculated current pulling-up speed.

5. A control system for the removal of a joint pipe of a super deep diaphragm wall based on the control method for the removal of a joint pipe of a super deep diaphragm wall according to any one of claims 1 to 4, characterized in that, The method comprises the following steps: A data acquisition module is used to collect joint pipe monitoring data by laying a sensor cluster on the inner wall of the joint pipe, including temperature data, height data, pressure data, and strain data; A joint pipe sectioning module is used to divide the joint pipe into a plurality of control sections in the depth direction according to the length of a single joint pipe; A pulling-up time monitoring module is used to determine the pulling-up time of different control sections according to the temperature inflection point method and the pressure turning point method; The pulling height monitoring module is configured to determine the pulling height at the current joint pipe depth according to the maximum control section number satisfying the pulling time and the length of the control section; The pulling speed adjusting module is configured to determine the current pulling speed of the joint pipe according to the actual pipe pulling resistance of the control section where the current pulling height is located and the rate of change of the formation pressure; The pipe pulling executing module is configured to execute the pulling operation of the joint pipe according to the current pulling speed when the current joint pipe working depth is greater than or equal to the current pulling height.

6. The super deep diaphragm wall joint pipe pulling control system according to claim 5, characterized in that, The pulling time monitoring module comprises: The initial setting time determining unit is configured to sequentially search for a first local minimum point of the temperature rate of change of all temperature data in the control section along the time axis within a time window of a preset search time range after pouring, as the initial setting time of the concrete; The pulling time determining unit is configured to determine the pulling time of the joint pipe control section when the collected pressure data is less than or equal to a preset pressure threshold on the basis of determining the initial setting time of the concrete.

7. The super deep diaphragm wall joint pipe pulling control system according to claim 5, characterized in that, The maximum control section number satisfying is determined at any time t The bottom depth of the pull-up height is calculated as the maximum control section number , denotes the length of a single joint pipe.​

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