A foundation pit monitoring and early warning system for hydraulic engineering
By generating theoretical and actual response sequences, anomalous zoning of pore pressure response order is identified, solving the problem of difficulty in locating hidden seepage risks in foundation pits in existing technologies, and achieving early identification and reliable early warning effects.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- ANHUI SHUIAN CONSTR GRP CO LTD
- Filing Date
- 2026-05-19
- Publication Date
- 2026-06-19
Smart Images
Figure CN122237692A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of water conservancy project construction safety monitoring technology, and in particular to a foundation pit monitoring and early warning system for water conservancy projects. Background Technology
[0002] Foundation pits in hydraulic engineering are commonly used in scenarios such as pumping stations, sluice gates, gate chambers, regulating reservoirs, culverts, river regulation projects, and foundation construction within cofferdams. Because these foundation pits are often located near rivers, canals, cofferdams, water storage areas, or underground confined aquifers, it is typically necessary to install dewatering wells, observation wells, pore pressure monitoring points, water level monitoring points, support structure deformation monitoring points, and drainage path monitoring points during the foundation pit construction process. This is to monitor information such as water level inside the pit, water level outside the pit, pore water pressure, support deformation, seepage flow rate, and seepage turbidity.
[0003] Existing methods for monitoring and warning the safety of foundation pits typically rely on whether pore water pressure, groundwater level, displacement of the support structure, or settlement exceeds preset thresholds to trigger an alarm. For foundation pit construction in water-rich strata, existing methods can also deploy pore pressure sensors or water level gauges in dewatering wells or observation wells to determine whether to continue or stop pumping based on groundwater drawdown, pore pressure changes, or the operating status of the dewatering wells.
[0004] However, in the foundation pit of a hydraulic engineering project, after the dewatering well is activated or the pumping intensity is adjusted, the change in pore water pressure is not only manifested as a change in numerical value, but also has obvious spatial propagation sequence characteristics. Under normal circumstances, pore pressure monitoring points close to the target dewatering well and located in the same aquifer as the target dewatering well's filtration section should usually respond earlier, while pore pressure monitoring points far from the target dewatering well should usually lag behind. Within the same aquifer, the pore pressure response usually delays with increasing horizontal distance. The response sequence of pore pressure monitoring points at different burial depths should also match the dewatering well filtration section, soil permeability, and cutoff wall arrangement.
[0005] When a foundation pit has local defects in the cutoff wall, permeable sand layers, weak areas at the cofferdam joints, confined water bypass channels at the bottom of the pit, or localized seepage anomalies, abnormal propagation phenomena may occur, such as pore pressure monitoring points far from the dewatering wells responding earlier than those near the wells, pore pressure monitoring points in the lower aquifer responding earlier than those in the upper aquifer, and pore pressure monitoring points in a certain section of the pit wall responding prematurely. In the early stages, these anomalies may not yet have caused the overall water level to exceed limits or the support displacement to exceed limits. Therefore, relying solely on single-point pore pressure thresholds, regional average pore pressure values, or support displacement thresholds is insufficient to promptly locate hidden weak areas in the cutoff wall or localized permeable channels.
[0006] Therefore, how to identify abnormal pore pressure propagation sequence phenomena and locate abnormal pore pressure response sequence zones by utilizing the response start time and response sequence of multiple pore pressure monitoring points within the influence range of the same dewatering well after its activation or adjustment has become a problem that needs to be solved in the safety monitoring and early warning of foundation pits in water conservancy projects. Summary of the Invention
[0007] This application provides a foundation pit monitoring and early warning system for water conservancy projects, which is used to identify hidden seepage anomalies in foundation pits based on the propagation sequence of pore pressure response after the operation of dewatering wells, thereby improving the pertinence and location of safety early warning for foundation pits in water conservancy projects.
[0008] Firstly, this application provides a method for safety monitoring and early warning of foundation pits in water conservancy projects. This method can be executed by a monitoring and early warning system, management equipment, edge computing devices, or a server. The method includes: acquiring precipitation event information, which is used to indicate the activation or adjustment of pumping intensity of target dewatering wells within the foundation pit; determining at least two target pore pressure monitoring points from multiple pore pressure monitoring points in the foundation pit based on the location, filtration section, and preset influence range of the target dewatering wells, wherein the soil layer to which the target pore pressure monitoring points belong has a hydraulic connection with the filtration section of the target dewatering wells; generating a theoretical response sequence for the at least two target pore pressure monitoring points based on the horizontal distance, burial depth, aquifer information, and soil permeability information between the at least two target pore pressure monitoring points and the target dewatering wells; acquiring the actual response start time of the at least two target pore pressure monitoring points within the response time window corresponding to the precipitation event information, and generating an actual response sequence based on the actual response start time; and determining whether there is an abnormal pore pressure response sequence partition in the foundation pit based on the sorting deviation between the theoretical sorting position of each target pore pressure monitoring point in the theoretical response sequence and the actual sorting position of each target pore pressure monitoring point in the actual response sequence.
[0009] Using the above method, the monitoring and early warning system does not solely rely on whether the pore pressure value exceeds the alarm threshold for early warning. Instead, after a dewatering well is activated or the pumping intensity is adjusted, it first identifies at least two target pore pressure monitoring points hydraulically connected to that well. Then, it generates theoretical and actual response sequences and judges whether the pore pressure propagation sequence is abnormal by analyzing the sorting deviation results. This allows for the identification of abnormal propagation patterns such as early response from distant points, early response from lower layers, or premature response on one side, providing a basis for locating risks of weak areas in the stop curtain, localized permeable channels, abnormal stratified seepage, or confined water bypassing the pit bottom.
[0010] In one possible design, determining at least two target pore pressure monitoring points from multiple pore pressure monitoring points in the foundation pit based on the location of the target dewatering well, the filtration section, and a preset influence range includes: acquiring the horizontal distance, burial depth, aquifer information, soil permeability information, foundation pit zoning information, and positional relationship relative to the cutoff wall between each of the multiple pore pressure monitoring points and the target dewatering well; and identifying pore pressure monitoring points whose horizontal distance is within the preset influence range and which meet the hydraulic connection determination conditions as the target pore pressure monitoring points; wherein, the hydraulic connection determination conditions include that the aquifer to which the pore pressure monitoring point belongs is in the same aquifer as the filtration section of the target dewatering well, or that there is no continuous aquitard between them, or that the pore pressure change of the pore pressure monitoring point reaches the test pumping response threshold during the test pumping process. This design avoids including pore pressure monitoring points with no obvious hydraulic connection to the target dewatering well in the response sequence judgment, improving the reliability of the comparison between the theoretical response sequence and the actual response sequence.
[0011] In one possible design, generating a theoretical response sequence for the at least two target pore pressure monitoring points based on their horizontal distance from the target dewatering well, burial depth, aquifer information, and soil permeability information includes: calculating a theoretical response score for each target pore pressure monitoring point, the theoretical response score being determined based on the horizontal distance between the target pore pressure monitoring point and the target dewatering well, the burial depth of the target pore pressure monitoring point, the permeability coefficient of the soil layer to which the target pore pressure monitoring point belongs, and the positional relationship of the target pore pressure monitoring point relative to the cutoff wall; and sorting the at least two target pore pressure monitoring points in ascending order of the theoretical response scores to generate the theoretical response sequence. This design eliminates reliance solely on horizontal distance sorting, further incorporating factors such as burial depth, soil permeability, and cutoff wall barrier characteristics, making the theoretical response sequence more consistent with the actual hydrogeological conditions of the foundation pit.
[0012] In one possible design, the theoretical response score is determined according to the following formula: Bj=α*dj / Ri+β*|zj-zf| / Z0+γ*Ij-δ*kj / kmax; Wherein, Bj represents the theoretical response score of the j-th target pore pressure monitoring point, dj represents the horizontal distance between the j-th target pore pressure monitoring point and the target precipitation well, Ri represents the influence radius corresponding to the preset influence range of the target precipitation well, zj represents the burial depth of the j-th target pore pressure monitoring point, zf represents the center depth of the filtration section of the target precipitation well, Z0 represents the depth normalization benchmark value, Ij represents the water-stop curtain barrier mark, kj represents the permeability coefficient of the soil layer to which the j-th target pore pressure monitoring point belongs, kmax represents the maximum permeability coefficient among the soil layers to which at least two target pore pressure monitoring points belong, and α, β, γ, and δ are weighting coefficients. Through this design, the generation process of the theoretical response sequence can be transformed into a calculable scoring and ranking process.
[0013] In one possible design, obtaining the actual response start time of the at least two target pore pressure monitoring points within the response time window corresponding to the precipitation event information includes: within the response time window, acquiring the pore water pressure value of each target pore pressure monitoring point according to a preset sampling interval; determining the reference pore pressure value of each target pore pressure monitoring point based on the pore water pressure values at multiple historical sampling times before the precipitation event; calculating the pore pressure change rate based on the pore water pressure values at adjacent sampling times; and determining the sampling time when the pore pressure change rate and the reference pore pressure value together satisfy a preset pore pressure response condition as the actual response start time of the corresponding target pore pressure monitoring point. This design can reduce the impact of a single noise point or instantaneous sensor jump on the determination of the response start time.
[0014] In one possible design, the preset pore pressure response conditions include: the pore pressure change rate is negative, and its absolute decrease is greater than a preset decrease rate threshold; and the number of samplings in which the pore pressure change rate continuously meets the preset decrease rate threshold reaches a preset number; or, the decrease in pore water pressure relative to the reference pore pressure value reaches a preset decrease magnitude threshold. If the target pore pressure monitoring point does not meet the preset pore pressure response conditions within the response time window, the actual response start time of the target pore pressure monitoring point is recorded as a preset delayed time after the end time of the response time window, and it is arranged after the target pore pressure monitoring points that have already responded; if two or more target pore pressure monitoring points meet the preset pore pressure response conditions at the same sampling time, they are prioritized according to the pore pressure decrease magnitude from largest to smallest; if the pore pressure decrease magnitudes are the same, they are sorted according to the order in the theoretical response sequence. Through this design, the actual response sequence has a complete sorting rule.
[0015] In one possible design, determining whether there is an anomalous pore pressure response sequence partition in the foundation pit based on the sorting deviation between the theoretical sorting position of each target pore pressure monitoring point in the theoretical response sequence and the actual sorting position of each target pore pressure monitoring point in the actual response sequence includes: obtaining the theoretical sorting position of each target pore pressure monitoring point in the theoretical response sequence and the actual sorting position in the actual response sequence; calculating the single-point deviation contribution value of each target pore pressure monitoring point based on the sorting difference between the theoretical and actual sorting positions; calculating the partition deviation contribution value of the corresponding foundation pit partition based on the single-point deviation contribution value of the target pore pressure monitoring points belonging to the same foundation pit partition; and determining the corresponding foundation pit partition as the anomalous pore pressure response sequence partition when the partition deviation contribution value reaches the partition deviation threshold. This design avoids judging risk solely based on overall deviation, and instead further locates the specific foundation pit partition.
[0016] In one possible design, the anomalous pore pressure response sequence partitioning is determined based on at least one of the following anomalous propagation modes: target pore pressure monitoring points farther from the target precipitation well respond earlier than those closer to the target precipitation well; target pore pressure monitoring points buried in the lower aquifer respond earlier than those buried in the upper aquifer; and target pore pressure monitoring points located within the same side wall partition reaching a preset proportion respond earlier than other side wall partitions within a preset concentrated response time window. This design allows for the identification of three engineering-significant anomalous propagation modes: far-point advance, lower-layer advance, and unilateral advance.
[0017] In one possible design, after determining whether there is an abnormal pore pressure response sequence zone in the foundation pit, the method further includes: acquiring the cutoff wall section, pit wall zone, or pit bottom zone corresponding to the abnormal pore pressure response sequence zone; generating a corresponding early warning level based on the pore pressure drop amplitude, response lead, and zone deviation contribution value of the target pore pressure monitoring points within the abnormal pore pressure response sequence zone; outputting the early warning level and the corresponding verification object; increasing the sampling frequency of the pore pressure monitoring points within the abnormal pore pressure response sequence zone, and acquiring at least one of the seepage turbidity and seepage flow rate on the drainage path corresponding to the abnormal pore pressure response sequence zone; increasing the early warning level of the abnormal pore pressure response sequence zone when the seepage turbidity meets a preset turbidity response condition, or the seepage flow rate meets a preset flow rate response condition, and the corresponding anomaly occurs within a preset verification time window after the abnormal pore pressure response sequence zone is determined. Through this design, the system can not only identify abnormal pore pressure propagation sequences but also output verification objects and perform encrypted monitoring and seepage response verification.
[0018] Secondly, this application provides a foundation pit monitoring and early warning system for water conservancy projects. The system includes a precipitation event acquisition module, a monitoring point determination module, a theoretical sequence generation module, an actual sequence generation module, and an anomaly zoning determination module. Each module is used to implement the methods described in the first aspect and its various embodiments.
[0019] Thirdly, this application also provides an electronic device, including at least one processor and at least one memory, wherein the at least one memory stores computer program instructions, and when the electronic device is running, the at least one processor executes the above-described method.
[0020] Fourthly, this application also provides a computer-readable storage medium storing a computer program that, when executed by a computer, causes the computer to perform the above-described method.
[0021] Compared with the prior art, this application has at least the following beneficial effects.
[0022] This application uses the sequence of pore pressure response after the operation of dewatering wells for early warning, instead of relying solely on whether a single pore pressure value, average pore pressure value, or water level value exceeds the limit. It can identify hidden seepage risks that have not yet caused obvious support displacement or overall water level anomalies in the early stages.
[0023] This application identifies anomalous propagation patterns such as early response at the far point, early response at the lower layer, and early response on one side by analyzing the ordering deviation between the theoretical response sequence and the actual response sequence. This can provide a basis for zoning and locating risks of weak areas in the stop curtain, local permeable channels, stratified seepage anomalies, or the risk of confined water bypassing the pit bottom.
[0024] This application provides clear data processing rules for judging abnormal pore pressure response sequence by using theoretical response score, actual response start time, single-point deviation contribution value, and zone deviation contribution value, thereby reducing the uncertainty of manual experience judgment.
[0025] After determining the abnormal zoning of pore pressure response sequence, this application further outputs the early warning level and the verification object, and can increase the pore pressure sampling frequency of the corresponding zoning, and perform verification in combination with the seepage turbidity or seepage flow rate on the drainage path, thereby improving the reliability of the early warning results. Attached Figure Description
[0026] Figure 1 This is a schematic diagram of the overall system architecture of a water conservancy project foundation pit monitoring and early warning system provided in an embodiment of this application.
[0027] Figure 2 A flowchart illustrating a method for monitoring and early warning of foundation pit safety in a water conservancy project, provided as an embodiment of this application.
[0028] Figure 3This is a schematic diagram illustrating the zoning relationship between target precipitation wells and target pore pressure monitoring points, provided as an embodiment of this application.
[0029] Figure 4 This is a schematic diagram comparing a theoretical response sequence and an actual response sequence, provided as an embodiment of this application.
[0030] Figure 5 This is a schematic diagram of an abnormal partitioned output of pore pressure response sequence provided in an embodiment of this application.
[0031] Figure 6 This is a schematic diagram of the system functional modules of a foundation pit monitoring and early warning system for a water conservancy project, provided as an embodiment of this application.
[0032] Figure 7 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Detailed Implementation
[0033] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings. It should be understood that the following embodiments are used to illustrate this application and are not intended to limit the scope of protection of this application.
[0034] In the embodiments of this application, "at least two" means two or more. "Multiple" means two or more. "Pore pressure monitoring point" refers to a monitoring point used to collect pore water pressure values, which can be composed of a pore water pressure gauge, a pore pressure sensor, or a monitoring device with pore pressure measurement function. "Target pore pressure monitoring point" refers to a pore pressure monitoring point that has a hydraulic connection with the precipitation event of the target precipitation well and is included in the pore pressure response sequence judgment. "Pore water pressure value" can be simply referred to as pore pressure value.
[0035] In this application's embodiments, "precipitation event information" is used to represent information about the target precipitation well starting up, stopping, increasing or decreasing pumping flow, changing pump frequency, or changing pumping mode. To facilitate differentiation among multiple precipitation wells, the i-th target precipitation well can be denoted as pi, the time when the target precipitation well starts up or its pumping intensity is adjusted can be denoted as ti, and the pumping intensity of the target precipitation well during the precipitation event can be denoted as qi; where qi can be characterized by pumping flow, pump frequency, pumping power, or a combination thereof. To highlight the core of this application, the following explanation mainly uses the starting up or adjustment of pumping intensity of a target precipitation well as an example.
[0036] In this application embodiment, the "preset influence range" can be the influence radius range centered on the target dewatering well, or it can be an irregular influence zone determined based on the formation permeability coefficient, the dewatering well filtration section, the location of the cutoff wall, and the boundary of the foundation pit zoning. If the influence radius is used, it is denoted as Ri. When the preset influence range is an irregular influence zone, Ri is the equivalent influence radius from the target dewatering well to the boundary of the irregular influence zone, or it is the maximum horizontal distance from the target dewatering well to the set of target pore pressure monitoring points.
[0037] In this embodiment, "hydraulic connection" refers to the ability to transmit groundwater pressure between the aquifer to which the target pore pressure monitoring point belongs and the filter section of the target precipitation well. Hydraulic connection can be determined through geological survey data, pumping test data, or historical precipitation event data. Specifically, when the aquifer to which the pore pressure monitoring point belongs and the filter section of the target precipitation well are located in the same aquifer, or when there is no continuous aquitard between them, or when the pore pressure change at the pore pressure monitoring point reaches the pumping test response threshold during the pumping test, a hydraulic connection can be determined between the soil layer to which the pore pressure monitoring point belongs and the filter section of the target precipitation well. The pumping test response threshold can be a preset multiple of the average pore pressure fluctuation amplitude of unrelated pore pressure monitoring points during the pumping test, or it can be the minimum effective value of the pore pressure change amplitude within the designed influence range of the target precipitation well during the pumping test.
[0038] Figure 1 This is a schematic diagram of the overall system architecture of a water conservancy engineering foundation pit monitoring and early warning system provided in an embodiment of this application. See also... Figure 1 The system may include a dewatering well operation acquisition unit, a pore pressure acquisition unit, a pit internal and external water level acquisition unit, a drainage path monitoring unit, a data processing unit, and an early warning output unit.
[0039] The dewatering well operation acquisition unit is used to collect the operating status of the target dewatering well, including start-up status, stop status, pumping flow rate, pump frequency, pumping power, and pumping mode. The pore pressure acquisition unit is used to collect pore water pressure values from multiple pore pressure monitoring points. The pit-inside-outside water level acquisition unit is used to collect water levels inside and outside the pit. The drainage path monitoring unit is used to collect the turbidity and flow rate of seepage water from drainage ditches, collection wells, or outlet points. The data processing unit is used to generate theoretical response sequences, actual response sequences, and calculate the sorting deviation results. The early warning output unit is used to output the pore pressure response sequence anomaly zones, early warning levels, and verification objects.
[0040] In one implementation, the data processing unit can be located in a field edge computing device or in a remote server. Field sensors can transmit data to the data processing unit via wired communication, wireless communication, or an industrial bus.
[0041] Figure 2This is a flowchart illustrating a method for monitoring and early warning of foundation pit safety in a water conservancy project, provided as an embodiment of this application. The method may include the following steps.
[0042] S101, Obtain precipitation event information. The monitoring and early warning system obtains the operating status of the target precipitation wells. When the i-th target precipitation well pi changes from a stopped state to an operating state, or when the pumping flow rate, pumping power, or pump frequency of the target precipitation well pi changes by more than a set proportion within a preset time, precipitation event information is generated, and the time ti of the precipitation event and the corresponding pumping intensity qi are recorded.
[0043] S102, Determine the target pore pressure monitoring points. Based on the location of the target precipitation well, the filtration section, and the preset influence range, the monitoring and early warning system determines at least two target pore pressure monitoring points from multiple pore pressure monitoring points.
[0044] S103, Generate theoretical response sequence. The monitoring and early warning system calculates theoretical response scores based on the horizontal distance between at least two target pore pressure monitoring points and the target precipitation well, the burial depth, the information of the aquifer, the permeability coefficient of the soil layer, and the barrier state of the cutoff wall, and generates a theoretical response sequence in ascending order of theoretical response scores.
[0045] S104, Generate the actual response sequence. The monitoring and early warning system collects pore pressure values from at least two target pore pressure monitoring points within the response time window, determines the actual response start time for each target pore pressure monitoring point, and generates the actual response sequence from earliest to latest according to the actual response start time.
[0046] S105, Identify the abnormal pore pressure response sequence zones. The monitoring and early warning system calculates the single-point deviation contribution value and the zone deviation contribution value based on the order deviation between the theoretical and actual response sequences. When the zone deviation contribution value reaches the zone deviation threshold, the corresponding pit zone is identified as an abnormal pore pressure response sequence zone.
[0047] In this embodiment, multiple pore pressure monitoring points can be deployed within the foundation pit. Each pore pressure monitoring point has a monitoring point number, planar coordinates, burial depth, information on the aquifer to which it belongs, information on the permeability of the soil layer to which it belongs, information on the foundation pit zoning to which it belongs, and its positional relationship relative to the cutoff wall.
[0048] The monitoring and early warning system can calculate the horizontal distance between the pore pressure monitoring point and the target precipitation well based on the plane coordinates of the target precipitation well and the plane coordinates of the pore pressure monitoring point. For the j-th pore pressure monitoring point, it can be denoted as mj, and its horizontal distance to the target precipitation well can be denoted as dj; the horizontal distance dj can be a planar projection distance, used to represent the spatial distance factor when the impact of the target precipitation well's pumping propagates from near to far.
[0049] In one implementation, when dj is less than or equal to the influence radius Ri of the target precipitation well, and there is a hydraulic connection between the aquifer to which the pore pressure monitoring point belongs and the filtration section of the target precipitation well, the pore pressure monitoring point is determined as the target pore pressure monitoring point. Here, Ri is the influence radius corresponding to the preset influence range of the i-th target precipitation well pi; when an irregular influence zone is used, Ri can be the equivalent influence radius or the maximum horizontal distance from the target precipitation well to the boundary of the target pore pressure monitoring point set.
[0050] In another implementation, if the influence range of the target dewatering well is affected by a water-stop curtain, a waterproof layer, or the boundary of a foundation pit section, the preset influence range may not be a circular radius range, but rather an irregular influence area enclosed by multiple section boundaries. In this case, if the pore pressure monitoring point is located within this irregular influence area and meets the hydraulic connection determination conditions, it is identified as the target pore pressure monitoring point.
[0051] By using the above methods, we can avoid having pore pressure monitoring points that have no obvious hydraulic connection with the target precipitation wells participate in the comparison of theoretical and actual response sequences.
[0052] In this embodiment, the monitoring and early warning system calculates a theoretical response score for each target pore pressure monitoring point. The smaller the theoretical response score, the earlier the target pore pressure monitoring point should respond under normal precipitation influence propagation conditions.
[0053] The theoretical response score can be determined using the following formula: Bj=α*dj / Ri+β*|zj-zf| / Z0+γ*Ij-δ*kj / kmax; Wherein, Bj represents the theoretical response score of the j-th target pore pressure monitoring point; dj represents the horizontal distance between the j-th target pore pressure monitoring point and the target dewatering well; Ri represents the influence radius corresponding to the preset influence range of the target dewatering well; zj represents the burial depth of the j-th target pore pressure monitoring point; zf represents the center depth of the filter section of the target dewatering well; Z0 represents the depth normalization benchmark value, used to convert the burial depth difference into a dimensionless quantity; Ij represents the water-stop curtain barrier marker corresponding to the j-th target pore pressure monitoring point; kj represents the permeability coefficient of the soil layer to which the j-th target pore pressure monitoring point belongs; kmax represents the maximum permeability coefficient in the set of target pore pressure monitoring points; α, β, γ, and δ are weighting coefficients, corresponding to the influence weights of horizontal distance, depth difference, water-stop curtain barrier, and soil permeability on the theoretical response order, respectively.
[0054] The water-stop curtain barrier marker Ij is used to characterize the degree to which the hydraulic transmission path between the j-th target pore pressure monitoring point and the target dewatering well is blocked by the water-stop curtain. When there is no water-stop curtain barrier between them, Ij is 0; when there is a continuous and complete water-stop curtain barrier, Ij is 1; when there are water-stop curtain joints, unpenetrated sections, local gaps, or weak construction overlaps, Ij can be determined according to the ratio of the blocked path length to the total hydraulic path length. Specifically, Ij = 1 - Lopen,j / Lpath,j, where Lopen,j represents the path length between the j-th target pore pressure monitoring point and the target dewatering well that is not blocked by the water-stop curtain, and Lpath,j represents the total hydraulic path length between them. If the path length cannot be obtained on-site, it can be assigned values of 0, 0.5, and 1 for no barrier, partial barrier, and continuous barrier, respectively.
[0055] In the above theoretical response scores, the larger Ij is, the stronger the barrier of the water-stop curtain, the larger the theoretical response score of the corresponding target pore pressure monitoring point, and the later its ranking in the theoretical response sequence; the larger kj is, the stronger the permeability of the soil layer, the smaller the theoretical response score of the corresponding target pore pressure monitoring point, and the earlier its ranking in the theoretical response sequence.
[0056] In one implementation, the weighting coefficients α, β, γ, and δ can be calibrated using response data from the test pumping phase. Specifically, during the test pumping phase, the actual response start time of each target pore pressure monitoring point is acquired, and a ranking of the actual test pumping responses is formed. The weighting coefficients are adjusted with the goal of minimizing the ranking deviation between the theoretical response score ranking and the actual test pumping response ranking. If test pumping data is unavailable, α+β+γ+δ=1 can be set, and the weighting coefficient α corresponding to the horizontal distance can be set to the maximum weight, subsequently corrected based on historical precipitation event data. The aforementioned weighting coefficients can be non-negative values to ensure that the direction of influence of each factor on the theoretical response score remains interpretable.
[0057] After calculating the theoretical response score for each target pore pressure monitoring point, the monitoring and early warning system sorts the theoretical response scores in ascending order to obtain the theoretical response sequence.
[0058] In this embodiment, the response time window can start from the moment ti (the time point in time) of the precipitation event and continue for a preset duration. For example, the response time window can be 0 to 120 minutes after the target precipitation well is activated, or it can be set to other durations according to the permeability of the engineering formation and the influence range of the precipitation well. ti is the reference time of the precipitation event, used to unify the starting point for comparing the response times of each target pore pressure monitoring point.
[0059] For the j-th target pore pressure monitoring point mj, the monitoring and early warning system acquires the pore pressure value uj(t) according to a preset sampling interval within the response time window. Here, uj(t) represents the pore water pressure value collected at time t at the j-th target pore pressure monitoring point, where t is the sampling time, and the preset sampling interval is denoted as δt. The preset sampling interval can be determined according to the engineering monitoring level, for example, 1 minute, 3 minutes, 5 minutes, or 10 minutes.
[0060] Before determining the actual response start time, the monitoring and early warning system first determines the reference orifice pressure value: uj0=(1 / n)*sum{r=1..n}uj(ti-r*δt); Where uj0 represents the reference pore pressure value at the j-th target pore pressure monitoring point; ti represents the time of the precipitation event; δt represents the sampling interval; n represents the number of historical sampling points used to calculate the reference pore pressure value; r represents the sequence number of the historical sampling points; and uj(ti-r*δt) represents the pore pressure value at the r-th historical sampling time before the precipitation event. By calculating uj0 using the n historical sampling values before ti, the influence of random fluctuations on the judgment of subsequent pore pressure decrease can be reduced.
[0061] The monitoring and early warning system further calculates the pore pressure change rate: vu,j(t)=[uj(t)-uj(t-δt)] / δt; Where vu,j(t) represents the rate of change of pore pressure at the j-th target pore pressure monitoring point at time t; uj(t) and uj(t-δt) represent the pore pressure values at the current sampling time and the previous sampling time, respectively; and δt is the time interval between two adjacent samplings.
[0062] In one implementation, when vu,j(t) is less than a preset falling rate threshold -Tu, and the number of consecutive samplings satisfying this condition reaches a preset number N0, the first sampling time that satisfies this continuous condition is determined as the actual response start time tu,j. Here, Tu represents the positive amplitude of the preset falling rate threshold, -Tu is used to represent the rate judgment boundary in the direction of pore pressure decrease; N0 represents the sampling number threshold for continuously satisfying the pore pressure response condition; and tu,j represents the actual response start time of the j-th target pore pressure monitoring point.
[0063] In another implementation, when the decrease in pore pressure relative to the reference pore pressure reaches a preset decrease threshold, the corresponding sampling time can also be determined as the actual response start time. Specifically, when uj0-uj(t)>=Uth, the j-th target pore pressure monitoring point can be considered to have reached the pore pressure response condition, where Uth represents the preset decrease threshold, used to limit the minimum effective decrease in pore pressure relative to the reference pore pressure.
[0064] If a target pore pressure monitoring point does not meet the preset pore pressure response condition within the response time window, the actual response start time of that target pore pressure monitoring point is recorded as a preset delay time after the end time of the response time window, and it is arranged after the target pore pressure monitoring points that have already responded. If there are multiple target pore pressure monitoring points that have not responded, they are arranged according to their order in the theoretical response sequence. If two or more target pore pressure monitoring points meet the preset pore pressure response condition at the same sampling time, they are prioritized according to the pore pressure drop magnitude from largest to smallest; if the pore pressure drop magnitudes are the same, they are arranged according to their order in the theoretical response sequence.
[0065] By using the above methods, the problem of the actual response sequence being unpredictable due to a single abnormal sample value, instantaneous sensor jumps, non-responding points, or parallel response points can be avoided.
[0066] In this embodiment, the monitoring and early warning system obtains the theoretical ranking position of each target pore pressure monitoring point in the theoretical response sequence, and records it as rank0(mj); it obtains the actual ranking position of each target pore pressure monitoring point in the actual response sequence, and records it as rank1(mj). Here, mj represents the j-th target pore pressure monitoring point, rank0(mj) represents the index of mj in the theoretical response sequence, and rank1(mj) represents the index of mj in the actual response sequence.
[0067] The monitoring and early warning system can calculate the single-point deviation contribution value according to the following formula: Dj=omegaj*|rank1(mj)-rank0(mj)|; Where Dj represents the single-point deviation contribution value of the j-th target pore pressure monitoring point; omegaj represents the weight of the j-th target pore pressure monitoring point, which is used to increase the deviation contribution ratio of monitoring points in key risk areas. For pore pressure monitoring points near the joints of the cutoff wall, the confined water sensitive area at the bottom of the pit, the historical leakage area, or the joint area of the cofferdam, a higher weight can be set.
[0068] The monitoring and early warning system further calculates the zoning deviation contribution value: Ds=sum{mjinZs}Dj; Where Ds represents the partition deviation contribution value of the s-th foundation pit partition; Zs represents the s-th foundation pit partition; mjinZs indicates that the j-th target pore pressure monitoring point belongs to the s-th foundation pit partition. By summing the deviation contribution values Dj of each single point within the same foundation pit partition Zs, the degree of anomaly in the response order at that partition level can be obtained.
[0069] When Ds reaches the zoning deviation threshold, the monitoring and early warning system identifies the s-th pit zoning as an abnormal pore pressure response sequence zoning. The zoning deviation threshold can be determined based on test pumping data, historical precipitation event data, the number of pore pressure monitoring points, and the project risk level. For example, the zoning deviation threshold can be a preset multiple of the maximum zoning deviation contribution value in normal precipitation events during the test pumping phase, or it can be determined by the early warning control value corresponding to the project monitoring level.
[0070] In one implementation, if the partition deviation contribution values of multiple pit partitions all reach the partition deviation threshold, the abnormal partition priority can be output in descending order of partition deviation contribution values.
[0071] In this embodiment, the monitoring and early warning system can identify the following three types of abnormal propagation patterns.
[0072] The first type is the far-point response. If the target pore pressure monitoring point far from the target dewatering well responds earlier than the target pore pressure monitoring point near the target dewatering well, it indicates that the pore pressure propagation may not be transmitted along the normal radial path, but may be transmitted to a distant location in advance through local permeable channels, sand layer interlayers, or weak points in the cutoff wall.
[0073] The second type is the lower layer responding first. If the target pore pressure monitoring point buried in the lower aquifer responds earlier than the target pore pressure monitoring point buried in the upper aquifer, and this response sequence does not match the permeability of the target dewatering well filtration section and the soil layer, it indicates that there may be deep confined water release, pit bottom bypass channels, or stratified seepage anomalies.
[0074] The third type is unilateral early response. If the target pore pressure monitoring points located in the same side wall section reach a preset proportion and respond earlier than other side wall sections within the preset concentrated response time window, it indicates that the side wall section may have weak cutoff wall joints, water seepage at the cofferdam connection, or local lateral flow around the flow.
[0075] The centralized response ratio can be determined according to the following formula: Ps=ns / Ns; Where Ps represents the convective response ratio of the s-th pit wall zone; ns represents the number of target pore pressure monitoring points that respond within the preset convective response time window in the s-th pit wall zone; and Ns represents the total number of target pore pressure monitoring points in the s-th pit wall zone. The preset convective response time window can be set based on the earliest responding target pore pressure monitoring point in the zone, according to the sampling interval and the engineering monitoring level.
[0076] When Ps reaches the preset ratio threshold, and the average actual response start time of this partition is earlier than the average actual response start time of other side wall partitions, it can be determined that this partition meets the single-sided early response mode.
[0077] In this embodiment, after determining the abnormal zone of pore pressure response sequence, the monitoring and early warning system obtains the water-stop curtain section, pit wall section or pit bottom section corresponding to the abnormal zone of pore pressure response sequence.
[0078] The monitoring and early warning system can generate an early warning evaluation value based on the pore pressure drop, response lead, and zonal deviation contribution: Rs=e1*δus / U0+e2*δts / T0+e3*Ds / D0; Where Rs represents the early warning evaluation value of the s-th pore pressure response sequence abnormal zone; δus represents the pore pressure drop amplitude of the target pore pressure monitoring point within the s-th pore pressure response sequence abnormal zone; U0 represents the baseline value of pore pressure drop amplitude; δts represents the response lead; T0 represents the baseline value of response lead; Ds represents the zone deviation contribution value; D0 represents the deviation baseline value; e1, e2, and e3 are weighting coefficients, corresponding to the contribution ratios of pore pressure drop amplitude, response lead, and zone deviation contribution value to the early warning evaluation value, respectively.
[0079] In one implementation, δus can be the maximum decrease in target pore pressure monitoring points relative to the reference pore pressure value within the s-th pore pressure response sequence anomalous zone, or the average decrease in target pore pressure monitoring points relative to the reference pore pressure value within that zone. δts can be the maximum lead time of target pore pressure monitoring points within that zone relative to the average response time of similar historical precipitation events, or the average lead time of target pore pressure monitoring points within that zone satisfying the anomalous propagation mode. If a theoretical response time model is not established in the project, the zone deviation contribution value Ds can be used instead of δts in the calculation of the early warning evaluation value.
[0080] A Level 1 warning is generated when Rs is within the first threshold range; a Level 2 warning is generated when Rs is within the second threshold range; and a Level 3 warning is generated when Rs reaches the third threshold. A Level 1 warning indicates that attention is needed, a Level 2 warning indicates that on-site verification is needed, and a Level 3 warning indicates that immediate verification of the dewatering well's operating status, the water-stop curtain section, or the corresponding pit bottom area is needed.
[0081] The objects to be reviewed may include target dewatering wells, abnormal pore pressure monitoring points, cutoff wall sections, pit wall zones, pit bottom zones, drainage ditches, or collection wells. The early warning output may include abnormal propagation patterns, theoretical response sequences, actual response sequences, zone deviation contribution values, early warning levels, and the objects to be reviewed.
[0082] In this embodiment, after outputting the warning level and the object to be reviewed, the monitoring and early warning system increases the sampling frequency of pore pressure monitoring points within the abnormal pore pressure response sequence zone. For example, the sampling interval is 10 minutes under normal conditions, and after determining the abnormal pore pressure response sequence zone, the sampling interval is adjusted to 1 minute or 3 minutes.
[0083] The monitoring and early warning system can also acquire the turbidity or flow rate of seepage water along the drainage path corresponding to the zone with abnormal pore pressure response sequence. The corresponding drainage path may include drainage ditches, sump wells, drainage channels at the bottom of pits, or water outlets inside the cofferdam near the zone.
[0084] The infiltration turbidity growth rate can be determined by the following formula: vC(t)=[C(t)-C(t-δt)] / δt; The seepage flow rate growth rate can be determined by the following formula: vQ(t)=[Q(t)-Q(t-δt)] / δt; Where C(t) represents the turbidity of the seepage at time t; Q(t) represents the seepage flow rate at time t; vC(t) represents the growth rate of the seepage turbidity; vQ(t) represents the growth rate of the seepage flow rate; and δt represents the time interval between two adjacent seepage monitoring samples. To avoid confusion with the target precipitation well pumping intensity qi, Q(t) in this embodiment only represents the seepage flow rate along the drainage path.
[0085] In this embodiment, the preset turbidity response condition may include the seepage turbidity growth rate reaching a preset turbidity growth rate threshold, or the seepage turbidity increasing over multiple consecutive sampling periods. The preset flow rate response condition may include the seepage flow rate growth rate reaching a preset flow rate growth rate threshold, or the increase in seepage flow rate relative to the baseline flow rate value before the determination of the pore pressure response sequence anomaly zone reaching a preset flow rate increase threshold. When the preset turbidity response condition or the preset flow rate response condition is met, and the corresponding anomaly occurs within a preset review time window after the determination of the pore pressure response sequence anomaly zone, the warning level of the pore pressure response sequence anomaly zone is increased.
[0086] This method combines abnormal pore pressure propagation sequence with seepage response along the drainage path, improving the reliability of early warning.
[0087] To facilitate understanding, a specific calculation example is given below. A target dewatering well, P1, is set up within the foundation pit of a water conservancy pumping station. The radius of influence Ri of P1 is 40m, the center depth zf of the filtration section is 18m, and the normalized depth reference value Z0 is 10m. Four target pore pressure monitoring points, M1, M2, M3, and M4, exist around P1, and can be designated as target pore pressure monitoring points m1 to m4, respectively.
[0088] M1 is 8m from P1, buried at a depth of 18m, with a soil permeability coefficient of 5 and a water-stop curtain barrier mark of 0; M2 is 16m from P1, buried at a depth of 17m, with a soil permeability coefficient of 4 and a water-stop curtain barrier mark of 0; M3 is 28m from P1, buried at a depth of 18m, with a soil permeability coefficient of 5 and a water-stop curtain barrier mark of 0; M4 is 34m from P1, buried at a depth of 20m, with a soil permeability coefficient of 5 and a water-stop curtain barrier mark of 0, but M4 is close to the north side water-stop curtain joint.
[0089] Let α = 0.5, β = 0.2, γ = 0.2, δ = 0.1, and kmax = 5. According to the theoretical response score formula, the theoretical response scores of M1, M2, M3, and M4 are arranged in ascending order as M1, M2, M3, M4. Therefore, the theoretical response sequence is: S0 = (M1, M2, M3, M4); After P1 is activated, the monitoring and early warning system extracts the actual response start time within the response time window. Actual monitoring results show that M4 responded at the 8th minute, M1 at the 14th minute, M2 at the 22nd minute, and M3 at the 30th minute. Therefore, the actual response sequence is: S1 = (M4, M1, M2, M3); Comparing the theoretical and actual response sequences, the theoretical ranking position of M4 is 4, while the actual ranking position is 1. If the weight omega4 of M4 is set to 1.5 due to its proximity to the seam of the water-stop curtain, then the single-point deviation contribution value of M4 is: D4 = 1.5 * |1 - 4| = 4.5; If the main abnormal contribution in the north pit wall partition comes from M4, and the partition deviation threshold is 3, then the partition deviation contribution value of the north pit wall partition reaches the partition deviation threshold, and the system determines the north pit wall partition as an abnormal partition in the pore pressure response sequence.
[0090] In one implementation, the zoning deviation threshold is determined based on the test pumping phase or historical normal precipitation events. Specifically, during the test pumping phase or historical normal precipitation events, the zoning deviation contribution value of each foundation pit zoning is calculated, and the maximum value of the corresponding zoning deviation contribution value under normal operating conditions is multiplied by a preset safety factor as the zoning deviation threshold. The preset safety factor can be 1.2 to 2.0; or, the sum of the mean of the corresponding zoning deviation contribution value under normal operating conditions and twice the standard deviation is used as the zoning deviation threshold.
[0091] Furthermore, since M4 is farther from P1 but responds first, the system identifies a "far point first response" pattern. Also, because M4 is close to the north-side water-stop curtain joint, the system outputs the north-side water-stop curtain joint section as the verification target. If the subsequent turbidity growth rate of the seepage water in the north-side drainage ditch reaches the preset turbidity growth rate threshold, the system will raise the corresponding warning level.
[0092] This example demonstrates that this application does not simply determine whether the pore pressure has decreased, but rather uses the deviation between the theoretical response sequence and the actual response sequence of the target pore pressure monitoring point to identify possible weak points in water stop or abnormal seepage channels.
[0093] Furthermore, Figure 6 This is a schematic diagram of the system functional modules of a foundation pit monitoring and early warning system for a water conservancy project, provided as an embodiment of this application. The system includes a precipitation event acquisition module, a monitoring point determination module, a theoretical sequence generation module, an actual sequence generation module, and an anomaly zoning determination module.
[0094] The precipitation event acquisition module is used to acquire precipitation event information, which is used to indicate the activation or adjustment of the pumping intensity of the target dewatering well in the foundation pit.
[0095] The monitoring point determination module is used to determine at least two target pore pressure monitoring points from multiple pore pressure monitoring points in the foundation pit based on the location of the target dewatering well, the filtration section, and the preset influence range. The soil layer to which the target pore pressure monitoring point belongs has a hydraulic connection with the filtration section of the target dewatering well.
[0096] The theoretical sequence generation module is used to generate theoretical response sequences for at least two target pore pressure monitoring points based on the horizontal distance between at least two target pore pressure monitoring points and the target precipitation well, the burial depth, the aquifer information, and the soil permeability information.
[0097] The actual sequence generation module is used to obtain the actual response start time of at least two target pore pressure monitoring points within the response time window corresponding to precipitation event information, and generate the actual response sequence based on the actual response start time.
[0098] The anomalous partitioning determination module is used to determine whether there are anomalous partitions in the pore pressure response sequence in the foundation pit based on the sorting deviation between the theoretical sorting position of each target pore pressure monitoring point in the theoretical response sequence and the actual sorting position of each target pore pressure monitoring point in the actual response sequence.
[0099] In one embodiment, the system may further include an early warning output module and a sampling control module. The early warning output module is used to output the early warning level and the corresponding review object; the sampling control module is used to increase the pore pressure sampling frequency of the corresponding partition after determining the abnormal partition of the pore pressure response sequence.
[0100] Figure 7 This is a schematic diagram of an electronic device provided in an embodiment of this application. The electronic device may include a processor, a memory, and a communication interface. The memory stores a computer program, and when the processor executes the computer program, it can implement the methods described in any of the above embodiments.
[0101] The communication interface can be used to receive the operating status of the dewatering well, pore water pressure value, water level inside and outside the pit, seepage turbidity and seepage flow rate, and can also be used to output the early warning level and the object to be reviewed.
[0102] This application also provides a computer-readable storage medium storing a computer program that, when executed by a computer, causes the computer to perform the methods described in any of the above embodiments.
[0103] It should be noted that, Figure 1 The acquisition unit, data processing unit, and early warning output unit shown are used to represent the hardware or data link architecture of the system; Figure 6 The functional modules shown represent the functional modules formed when the data processing unit or processor executes a computer program. They belong to different expression levels of the same foundation pit monitoring and early warning system and are not two independent systems.
Claims
1. A foundation pit monitoring and early warning system for water conservancy projects, characterized in that, include: The precipitation event acquisition module is used to acquire precipitation event information, which is used to indicate the activation or adjustment of the pumping intensity of the target dewatering well in the foundation pit. The monitoring point determination module is used to determine at least two target pore pressure monitoring points from multiple pore pressure monitoring points in the foundation pit based on the location of the target dewatering well, the filtration section, and the preset influence range. The soil layer to which the target pore pressure monitoring point belongs has a hydraulic connection with the filtration section of the target dewatering well. The theoretical sequence generation module is used to generate a theoretical response sequence for the at least two target pore pressure monitoring points based on the horizontal distance, burial depth, aquifer information, and soil permeability information between the at least two target pore pressure monitoring points and the target precipitation well; The actual sequence generation module is used to obtain the actual response start time of the at least two target pore pressure monitoring points within the response time window corresponding to the precipitation event information, and generate an actual response sequence based on the actual response start time. The anomalous partitioning determination module is used to determine whether there is an anomalous partitioning of the pore pressure response sequence in the foundation pit based on the sorting deviation between the theoretical sorting position of each target pore pressure monitoring point in the theoretical response sequence and the actual sorting position of each target pore pressure monitoring point in the actual response sequence.
2. The foundation pit monitoring and early warning system for water conservancy projects according to claim 1, characterized in that, The monitoring point determination module is used for: The horizontal distance, burial depth, aquifer information, soil permeability information, foundation pit zoning information, and positional relationship relative to the cutoff wall between the multiple pore pressure monitoring points and the target dewatering well are obtained. The pore pressure monitoring points that are horizontally located within the preset influence range and meet the hydraulic connection determination conditions are identified as the target pore pressure monitoring points. The hydraulic connection determination conditions include that the aquifer to which the pore pressure monitoring point belongs and the filtration section of the target dewatering well are in the same aquifer, or there is no continuous aquitard between them, or the pore pressure change of the pore pressure monitoring point reaches the test pumping response threshold during the test pumping process.
3. The foundation pit monitoring and early warning system for water conservancy projects according to claim 1, characterized in that, The theoretical sequence generation module is used for: For each target pore pressure monitoring point, a theoretical response score is calculated. The theoretical response score is determined based on the horizontal distance between the target pore pressure monitoring point and the target dewatering well, the burial depth of the target pore pressure monitoring point, the permeability coefficient of the soil layer to which the target pore pressure monitoring point belongs, and the positional relationship of the target pore pressure monitoring point relative to the water-stopping curtain. The at least two target pore pressure monitoring points are sorted in ascending order of the theoretical response score to generate the theoretical response sequence; When the preset influence range is an irregular influence area, the equivalent influence radius from the target precipitation well to the boundary of the irregular influence area, or the maximum horizontal distance from the target precipitation well to the set of target pore pressure monitoring points, is used as the influence radius in the theoretical response score.
4. The foundation pit monitoring and early warning system for water conservancy projects according to claim 3, characterized in that, The theoretical sequence generation module is used to determine the theoretical response score value according to the following formula: Bj=α*dj / Ri+β*|zj-zf| / Z0+γ*Ij-δ*kj / kmax; Wherein, Bj represents the theoretical response score of the j-th target pore pressure monitoring point, dj represents the horizontal distance between the j-th target pore pressure monitoring point and the target precipitation well, Ri represents the influence radius corresponding to the preset influence range of the target precipitation well, zj represents the burial depth of the j-th target pore pressure monitoring point, zf represents the center depth of the filtration section of the target precipitation well, Z0 represents the depth normalization benchmark value, Ij represents the water-stop curtain barrier mark, kj represents the permeability coefficient of the soil layer to which the j-th target pore pressure monitoring point belongs, kmax represents the maximum permeability coefficient in the soil layers to which at least two target pore pressure monitoring points belong, and α, β, γ, and δ are weighting coefficients; Wherein, Ij is used to characterize the degree to which the hydraulic transmission path between the j-th target pore pressure monitoring point and the target precipitation well is blocked by the water-stop curtain. The larger Ij is, the later the target pore pressure monitoring point is in the theoretical response sequence; the larger kj is, the earlier the target pore pressure monitoring point is in the theoretical response sequence.
5. The foundation pit monitoring and early warning system for water conservancy projects according to claim 1, characterized in that, The actual sequence generation module is used for: Within the response time window, the pore water pressure value of each target pore pressure monitoring point is acquired according to a preset sampling interval; The baseline pore pressure value for each target pore pressure monitoring point is determined based on the pore water pressure values at multiple historical sampling times prior to the precipitation event. The rate of change of pore pressure is calculated based on the pore water pressure values at adjacent sampling times; The sampling time at which the pore pressure change rate and the reference pore pressure value together satisfy the preset pore pressure response condition is determined as the actual response start time of the corresponding target pore pressure monitoring point.
6. The foundation pit monitoring and early warning system for water conservancy projects according to claim 5, characterized in that, The actual sequence generation module is also used for: When the pore pressure change rate is negative, and its absolute decrease is greater than a preset decrease rate threshold, and the number of samplings in which the pore pressure change rate continuously meets the preset decrease rate threshold reaches a preset number, the corresponding target pore pressure monitoring point is determined to meet the preset pore pressure response condition. Alternatively, when the decrease in pore water pressure value relative to the reference pore pressure value reaches a preset decrease threshold, it is determined that the corresponding target pore pressure monitoring point meets the preset pore pressure response condition. If the target pore pressure monitoring point does not meet the preset pore pressure response condition within the response time window, the actual response start time of the target pore pressure monitoring point is recorded as the preset delayed time after the end time of the response time window, and the target pore pressure monitoring point is arranged after the target pore pressure monitoring points that have already responded. If two or more target pore pressure monitoring points meet the preset pore pressure response conditions at the same sampling time, they are prioritized to be sorted from largest to smallest pore pressure drop. If the pore pressure drop is the same, they are sorted according to the order in the theoretical response sequence.
7. The foundation pit monitoring and early warning system for water conservancy projects according to claim 1, characterized in that, The abnormal partition determination module is used for: Obtain the theoretical ranking position of each target pore pressure monitoring point in the theoretical response sequence and the actual ranking position in the actual response sequence; Based on the sorting difference between the theoretical sorting position and the actual sorting position, calculate the single-point deviation contribution value of each target pore pressure monitoring point; Based on the single-point deviation contribution value of the target pore pressure monitoring points belonging to the same foundation pit zone, calculate the zone deviation contribution value of the corresponding foundation pit zone; When the partition deviation contribution value reaches the partition deviation threshold, the corresponding pit partition is determined as the abnormal partition of the pore pressure response sequence.
8. The foundation pit monitoring and early warning system for water conservancy projects according to claim 7, characterized in that, The anomalous partitioning determination module is further configured to determine the pore pressure response sequence anomalous partitioning based on at least one of the following anomalous propagation modes: The target pore pressure monitoring point farther away from the target precipitation well responds earlier than the target pore pressure monitoring point closer to the target precipitation well; The target pore pressure monitoring point buried in the lower aquifer responds earlier than the target pore pressure monitoring point buried in the upper aquifer; Target pore pressure monitoring points located within the same side wall zone that reach a preset proportion will respond earlier than other side wall zones within the preset concentrated response time window. Wherein, "earlier" is determined based on the actual response start time.
9. The foundation pit monitoring and early warning system for water conservancy projects according to claim 7, characterized in that, The system also includes an early warning output module and a sampling control module; The early warning output module is used to obtain the water-stop curtain section, pit wall section or pit bottom section corresponding to the abnormal pore pressure response sequence section, and generate the corresponding early warning level based on the pore pressure drop amplitude, response advance and section deviation contribution value of the target pore pressure monitoring point in the abnormal pore pressure response sequence section, and output the early warning level and the corresponding review object. The sampling control module is used to increase the sampling frequency of pore pressure monitoring points within the pore pressure response sequence abnormal zone, and to obtain at least one of the seepage turbidity and seepage flow rate on the drainage path corresponding to the pore pressure response sequence abnormal zone; When the seepage turbidity meets the preset turbidity response condition, or the seepage flow rate meets the preset flow rate response condition, and the corresponding anomaly occurs within the preset verification time window after the abnormal pore pressure response sequence partition is determined, the early warning output module increases the early warning level of the abnormal pore pressure response sequence partition.
10. The foundation pit monitoring and early warning system for water conservancy projects according to any one of claims 1 to 9, characterized in that, The system includes a processor, memory, and a communication interface; The communication interface is used to receive the operating status data of the target dewatering well, the pore water pressure values of the multiple pore pressure monitoring points, the water level values inside and outside the foundation pit, and the turbidity or flow rate of seepage water on the drainage path. The memory is used to store computer programs as well as the location of the target dewatering well, the filtration section, the preset influence range, the location of the pore pressure monitoring point, the burial depth of the pore pressure monitoring point, the information of the aquifer to which it belongs, the permeability information of the soil layer to which it belongs, the information of the foundation pit zoning, and the location information of the water-stop curtain. The processor is used to run the computer program to call the precipitation event acquisition module, monitoring point determination module, theoretical sequence generation module, actual sequence generation module and anomalous partition determination module, and output the pore pressure response sequence anomalous partition, warning level and verification object.