Mountain torrent and debris flow multi-parameter forecasting method based on roughness relationship

Abstract

The invention provides a mountain torrent and debris flow multi-parameter forecasting method based on the roughness relationship, and relates to the technical field of geological disaster prevention and control. According to the embodiment of the invention, the coupling relation between the fluid roughness and the flow is established through the key parameters such as the water depth and the flow velocity which are obtained through actual monitoring, the fluid characteristic change trend is fused, and a multi-parameter and multi-level disaster early warning model is constructed. According to the embodiment of the invention, the property change of the fluid can be judged through the parameters such as the water depth and the roughness, the mountain torrent and the debris flow are classified and judged, and the possible development trend and the danger degree are predicted accordingly. Compared with the prior art, the method has the advantages that the coupling relation among the multi-source monitoring data is fully utilized, the disaster type identification and forecasting precision and reliability are improved, and the method has high engineering practical value and popularization prospect.

Description

TECHNICAL FIELD

[0001] The embodiment of the present application relates to the technical field of geological disaster prevention, and particularly relates to a mountain torrent and debris flow multi-parameter prediction method based on roughness relationship. BACKGROUND

[0002] The mountain torrent and debris flow are common natural disasters in small mountainous basins, which bring serious threat to people's life and property safety. The mountain torrent and debris flow monitoring and early warning are the most economical and effective means of disaster reduction, which can provide valuable time for disaster prevention and reduction, and have important significance for social stability and economic development.

[0003] In theory, the change of mountain river starts from the mountain flood caused by rainfall, and then the debris flow is formed with the addition of sediment and stones. Compared with the ordinary mountain torrent, the debris flow has stronger impact and higher danger due to carrying a large amount of solid materials (such as stones). The prevention and control means of mountain torrent and debris flow are significantly different, and therefore, it is crucial to accurately judge the fluid property for disaster monitoring and early warning. However, the research on the fluid property of mountain torrent and debris flow is still insufficient at present, and the existing monitoring and early warning methods cannot meet the actual disaster prevention and reduction needs. SUMMARY

[0004] The embodiment of the present application provides a mountain torrent and debris flow multi-parameter prediction method based on roughness relationship, so as to at least partially solve the problems in the related art.

[0005] The first aspect of the embodiment of the present application provides a mountain torrent and debris flow multi-parameter prediction method based on roughness relationship, and the method comprises the following steps. Obtaining a plurality of historical water depth monitoring values and a plurality of corresponding historical flow velocity monitoring values of a target basin; According to the historical water depth monitoring values and the corresponding historical flow velocity monitoring values, determining a critical water depth-flow velocity point and a critical roughness at which the flood is converted into the debris flow; According to the relationship among the flow, the water depth and the roughness, calculating the relationship curves among the flow, the water depth and the roughness of the flood and the debris flow respectively; After obtaining the critical water depth and the critical roughness, realizing the early warning of the debris flow by monitoring the relationship among the water depth, the roughness and the critical water depth-flow velocity point, and determining the early warning level.

[0006] Optionally, the method further comprises the following steps. Based on the critical water depth and the corresponding flow velocity monitoring value, determining the critical flow threshold value at which the mountain torrent and the debris flow occur by using the following formula: Q0= V0H0L; Wherein, Q0 represents the critical flow threshold value, and the unit is cubic meter / second; L represents the river cross-section width of the target basin, H0 represents the critical water depth, and V0 represents the corresponding flow velocity monitoring value. outputting the critical water depth and the critical flow threshold.

[0007] Optionally, the relationship curves between the flow and the water depth and the roughness of the flood and the debris flow are calculated respectively according to the relationship between the flow and the water depth and the roughness, including: According to the following formula: Q = V H L=(1 / n)H 5 / 3 S 1 / 2 L; Wherein, Q represents the flow, L represents the cross-sectional width of the river, n represents the roughness, H represents the water depth, and S represents the gradient of the river. The relationship curves between the flow and the water depth and the roughness of the flood and the debris flow are calculated respectively.

[0008] Optionally, the method further comprises: determining the current fluid roughness according to the current water depth monitoring value and the current flow rate monitoring value, and determining the current flow increase rate reduction degree according to the current fluid roughness and the mountain torrent roughness; the flow increase rate reduction degree represents the degree of reduction of the flow increase rate due to the increase of the internal roughness of the debris flow; determining the warning level according to the current flow increase rate reduction degree.

[0009] Optionally, the warning of the debris flow is realized by monitoring the relationship between the water depth, the roughness and the critical water depth-flow rate point, and the warning level is determined, including: In the case that the current water depth monitoring value is greater than the critical water depth, and the current flow increase rate reduction degree is greater than the flow increase rate reduction degree threshold, the warning level is determined to be a first-level warning; In the case that the current water depth monitoring value is greater than the critical water depth, and the current flow increase rate reduction degree is less than or equal to the flow increase rate reduction degree threshold, the warning level is determined to be a second-level warning; In the case that the current water depth monitoring value is less than or equal to the critical water depth, and the current flow increase rate reduction degree is greater than the flow increase rate reduction degree threshold, the warning level is determined to be a third-level warning; In the case that the current water depth monitoring value is less than or equal to the critical water depth, and the current flow increase rate reduction degree is less than or equal to the flow increase rate reduction degree threshold, the warning level is determined to be a fourth-level warning.

[0010] Optionally, the method further comprises: calculating the first flow increase rate reduction degree corresponding to the first water depth monitoring value according to the relationship curves between the flow and the water depth and the roughness of the flood and the debris flow; The second flow increase amplitude reduction degree is calculated according to the relationship curve between the flow and the water depth and the roughness of the flood and the debris flow, and the flow increase amplitude reduction degree represents a degree of reduction of the flow increase amplitude caused by the increase of the internal roughness of the debris flow. According to the first flow increase amplitude reduction degree and the second flow increase amplitude reduction degree and the first water depth monitoring value and the second water depth monitoring value, a dangerous change amplitude is determined, and a dangerous change early warning prompt is output based on the dangerous change amplitude.

[0011] The second aspect of the embodiment of the application provides a mountain torrent and debris flow multi-parameter prediction device based on a roughness relationship, and the device comprises: A parameter acquisition module is configured to acquire a plurality of historical water depth monitoring values and a plurality of corresponding historical flow velocity monitoring values of a target flow domain. A critical water depth determination module is configured to determine a critical water depth-flow velocity point and a critical roughness of a flood converted into a debris flow according to the historical water depth monitoring values and the corresponding historical flow velocity monitoring values. A relationship curve determination module is configured to calculate relationship curves between the flow and the water depth and the roughness of the flood and the debris flow respectively according to the relationship between the flow and the water depth and the roughness. An early warning module is configured to realize early warning of the debris flow by monitoring the relationship between the water depth, the roughness and the critical water depth-flow velocity point after the critical water depth and the critical roughness are obtained, and determine an early warning level.

[0012] The third aspect of the embodiment of the application provides an electronic device, which comprises a memory, a processor and a computer program stored in the memory and executable on the processor, and the processor realizes the mountain torrent and debris flow multi-parameter prediction method based on the roughness relationship when executed.

[0013] The fourth aspect of the embodiment of the application provides a computer readable storage medium, which stores a computer program, and the program realizes the mountain torrent and debris flow multi-parameter prediction method based on the roughness relationship when executed by a processor.

[0014] The fifth aspect of the embodiment of the application provides a computer program product, which comprises a computer program / instruction, and the computer program / instruction realizes the steps in the mountain torrent and debris flow multi-parameter prediction method based on the roughness relationship when executed by a processor.

[0015] Compared with the related art, the embodiment of the application has the following beneficial effects: (1) The related art generally sets a warning threshold according to a single parameter monitored, and the function is single and the error is large. The embodiment of the present application realizes a warning method based on flow and roughness through the relationship between the multiple parameters (flow rate and water depth) actually monitored, and simultaneously predicts multiple parameters and multiple levels such as the occurrence threshold and flow of the debris flow.

[0016] (2) The related art is difficult to consider the change of the fluid property in the prediction and warning of the debris flow. The embodiment of the present application identifies the change of the fluid property through parameters such as water depth and roughness, can distinguish between mountain torrents and debris flows, and can predict the change trend of the fluid hazard according to the change trend of the parameters.

[0017] In summary, the technical scheme provided by the embodiment of the present application is not only dependent on a single monitoring parameter, but also based on the relationship between multiple parameters such as water depth, flow, and roughness, and establishes a multi-parameter and multi-index warning level system. This method can identify the change of the fluid property and predict the change trend of the fluid hazard. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical scheme of the embodiment of the present application, the drawings needed in the description of the embodiment of the present application will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creating laborious work.

[0019] Figure 1 A step flow chart of the multi-parameter prediction method of mountain torrents and debris flows based on the roughness relationship provided by the embodiment of the present application is shown; Figure 2 A trend graph of the exemplary roughness change with water depth provided by the embodiment of the present application is shown; Figure 3 An exemplary analysis process diagram of the degree of flow increase rate reduction provided by the embodiment of the present application is shown; Figure 4 A structural block diagram of the multi-parameter prediction device of mountain torrents and debris flows based on the roughness relationship provided by the embodiment of the present application is shown. DETAILED DESCRIPTION

[0020] In order to make the above-mentioned purposes, features and advantages of the present application more apparent and easy to understand, the present application will be further described in detail below with reference to the drawings and specific embodiments.

[0021] Currently, the monitoring parameters of mountain torrents and debris flows include rainfall, water level, flow rate, etc., and the warning threshold is usually set according to these monitoring data. However, due to the suddenness and complexity of the debris flow, the monitoring of only a single parameter often leads to inaccurate results, and false or missed reports occur from time to time.

[0022] The main problems existing in the current monitoring and early warning method include: Dependence on historical rainfall for prediction: The current debris flow prediction mostly depends on the statistical method of historical rainfall data, which can usually only predict whether the disaster occurs or not, but cannot accurately predict the specific time and severity; Ignoring the flow process and fluid properties: The current monitoring and early warning method only focuses on the occurrence time of debris flow, ignoring the flow process and fluid property changes, which are crucial for accurate prediction of debris flow risk.

[0023] Large error in prediction results: Since the current early warning method relies on the monitoring results of a single parameter, it is difficult to reasonably set the early warning threshold and level, resulting in large error and affecting the accuracy of early warning.

[0024] To solve the above problems, the embodiments of the present application propose to change the current monitoring and early warning idea, to comprehensively monitor multiple parameters, and to establish the correlation between each parameter. On the one hand, multiple parameters can verify each other, improving the reliability of data; on the other hand, by analyzing the relationship of these parameters, the time, flow and fluid properties of mountain torrents and debris flows are calculated more scientifically, and then the early warning levels are accurately divided. Therefore, the inventive concept proposed by the embodiments of the present application helps to improve the accuracy of the early warning system, reduce false positives and omissions, and improve the disaster early warning and prevention and emergency response capabilities.

[0025] Specifically, in the embodiments of the present application, a mountain torrent and debris flow multi-parameter prediction method based on roughness relationship is provided, as shown in Figure 1 The step flow chart of the mountain torrent and debris flow multi-parameter prediction method based on roughness relationship provided by the embodiments of the present application is shown in Figure 1 Specifically, the method comprises the following steps: S101, obtaining multiple historical water depth monitoring values and corresponding multiple historical flow rate monitoring values of a target basin.

[0026] S102, determining the critical water depth-flow rate point and the critical roughness of the conversion of flood to debris flow according to the historical water depth monitoring values and the corresponding historical flow rate monitoring values.

[0027] S103, calculating the relationship curves between the flow and the water depth, roughness of flood and debris flow respectively according to the relationship between the flow and the water depth, roughness.

[0028] S104, after obtaining the critical water depth and the critical roughness, realizing the early warning of debris flow and determining the early warning level by monitoring the relationship between the water depth, roughness and the critical water depth-flow rate point.

[0029] In the embodiment of the present application, the historical monitoring data of the target river basin can be acquired first, and the historical monitoring data includes a plurality of historical water depth monitoring values and a plurality of corresponding historical flow rate monitoring values, each historical water depth monitoring value and historical flow rate monitoring value correspond to each other.

[0030] In the embodiment of the present application, the plurality of historical monitoring data is obtained by monitoring the same river section of the target river basin. In the embodiment of the present application, the historical monitoring data can further include a historical flow monitoring value, so as to verify the historical water depth monitoring value and the corresponding historical flow rate monitoring value based on the historical flow monitoring value, thereby improving the reliability of the data.

[0031] In the embodiment of the present application, the water depth and the flow rate are key properties of the mountain torrent debris flow fluid, and the relationship between the water depth and the flow rate is as follows: V=(1 / n)H 2 / 3 S 1 / 2 (1) Wherein, V is the flow rate, the unit is meter / second (m / s), H is the water depth, the unit is meter (m), S is the river gradient of the target river basin, and n is the fluid roughness. The roughness of the mountain torrent and the debris flow is significantly different. Due to the increase of the solid content, the debris flow fluid roughness n2 is greater than the mountain torrent roughness n1. In the embodiment of the present application, the debris flow roughness and the mountain torrent roughness can both adopt the empirical value. In the embodiment of the present application, the river gradient of the target river basin can be obtained from the digital terrain elevation data.

[0032] Further, in the embodiment of the present application, the flow rate Q can be calculated by the following formula: Q = V H L=(1 / n)H 5 / 3 S 1 / 2 L(2) Wherein, Q is the flow rate, the unit is cubic meter / second (m³ / s); and L is the river cross section width (m).

[0033] In the embodiment of the present application, the relationship curve between the flow rate and the water depth and the roughness of the flood and the debris flow can be calculated based on formula (2), wherein when the relationship curve between the flow rate and the water depth and the roughness of the flood is calculated, n is the flood roughness, and when the relationship curve between the flow rate and the water depth and the roughness of the debris flow is calculated, n is the debris flow roughness.

[0034] In the embodiment of the present application, the water depth and the flow rate of the mountain torrent and the debris flow respectively satisfy the following relationships: V=(1 / n1)H 2 / 3 S 1 / 2 (mountain torrent) (3) V=(1 / n2)H 2 / 3 S 1 / 2 (debris flow) (4) Since the debris flow roughness n2 is greater than the torrent roughness n1, under the same water depth condition, the flow velocity of the debris flow is relatively slow, thereby affecting the calculation of the flow.

[0035] In the embodiment of the present application, the torrent roughness and the debris flow roughness can be calculated based on the actually monitored water depth monitoring value and the corresponding historical flow velocity monitoring value.

[0036] In the embodiment of the present application, the torrent roughness generally refers to the riverbed roughness, that is, the external roughness, while the roughness of the debris flow includes the external roughness and the internal roughness, that is, n2>n1.

[0037] In the embodiment of the present application, considering that due to the difference between n1 and n2, as the water depth of the fluid increases, the flow velocity also increases, and then the flow increases, the transition from the torrent to the debris flow is prone to occur, and when the transition from the torrent to the debris flow occurs, the roughness caused by the internal friction of the debris flow, that is, the internal roughness of the debris flow, the trend of the flow velocity increasing with the water depth slows down. Moreover, the greater the soil content in the debris flow, the more unstable the fluid, the greater the roughness, the slower the trend of the flow velocity increasing with the water depth, and the slower the trend of the flow increasing with the water depth.

[0038] Based on this, the embodiment of the present application proposes that a plurality of theoretical flow velocities corresponding to a plurality of historical water depth monitoring values and the torrent roughness are calculated; and then the critical water depth at which the target flow area occurs torrent and debris flow is determined according to the plurality of historical water depth monitoring values, the plurality of historical flow velocity monitoring values and the plurality of theoretical flow velocities.

[0039] Specifically, in the torrent stage, the theoretical flow velocity corresponding to the historical water depth monitoring value and the torrent roughness can be calculated based on the above formula (1). Correspondingly, the theoretical flow velocity is close to the corresponding flow velocity monitoring value. With the transition from the torrent to the debris flow, in the debris flow stage, the trend of the flow velocity increasing with the water depth slows down due to the roughness caused by the internal friction of the debris flow. Correspondingly, the difference between the theoretical flow velocity calculated based on the water depth monitoring value and the torrent roughness and the actual flow velocity monitoring value is large.

[0040] Therefore, based on the calculated theoretical flow velocity and the actually monitored flow velocity monitoring value, the critical water depth-flow velocity point at which the torrent and the debris flow occur can be determined, and the corresponding critical water depth of the critical water depth-flow velocity point can be obtained.

[0041] In the embodiment of the present application, the corresponding roughness can also be calculated based on the historical water depth monitoring value and the corresponding historical flow velocity monitoring value based on the above formula (1), as shown in Figure 2 , which shows a trend diagram of an exemplary roughness changing with water depth. As can be seen from the example of Figure 2 , the critical point at which the roughness starts to increase can be determined, and the water depth corresponding to the critical point is further taken as the critical water depth H0.

[0042] Further, in the embodiment of the present application, based on Figure 2 And the formula (3), (4), can also be calculated to get the mountain torrent roughness and the fluid roughness in the development process of debris flow.

[0043] In the embodiment of the present application, further can be based on the above formula (2) to calculate the critical flow threshold Q0 corresponding to the critical water depth-depth-flow rate point.

[0044] In the embodiment of the present application, the critical water depth H0 and the critical flow Q0 can be output as one of the early warning parameters.

[0045] Based on this, in the embodiment of the present application, the method further comprises the following steps: S105, based on the critical water depth and the corresponding flow rate monitoring value, the following formula is used to determine the critical flow threshold of mountain torrent and debris flow: Q0= V0H0L; Wherein, Q0 represents the critical flow threshold, the unit is cubic meter / second; L represents the river cross section width of the target basin, H0 represents the critical water depth, V0 represents the corresponding flow rate monitoring value.

[0046] S106, output the critical water depth and the critical flow threshold.

[0047] In actual application process, in the embodiment of the present application, the river section of the target basin can be continuously monitored in the mountain torrent process, the water depth monitoring value and the historical monitoring value are obtained, the water depth monitoring value and the monitoring value obtained at the same time are taken as a group of monitoring data, so as to continuously obtain a plurality of groups of monitoring data, and the plurality of groups of monitoring data are continuously analyzed, when the roughness begins to increase, the water depth monitoring value in the corresponding monitoring data is determined as the critical water depth H0, and the critical flow threshold Q0 is further determined according to the water depth monitoring value and the flow rate monitoring value in the group of monitoring data. And, continue to continuously monitor the river section, obtain a plurality of groups of monitoring data monitored in the development process of debris flow after the mountain torrent is converted to debris flow, and continue to analyze these monitoring data to analyze the development of debris flow.

[0048] In the embodiment of the present application, further based on the above formula (2), the mountain torrent flow theoretical value (assuming that the mountain torrent flow can change with the theoretical value of the flow rate and the water depth under the condition of not occurring debris flow) corresponding to each water depth monitoring value can be calculated. Further, the trend curve of the mountain torrent flow theoretical value with the water depth can be obtained, as shown in Figure 3 The exemplary analysis process schematic diagram of the flow increase amplitude slowing down degree is shown, and Figure 3In the embodiment, the curve Q1 represents a trend curve of the theoretical value of the flood flow with the water depth, and the curve Q2 represents a trend curve of the flow of the debris flow with the water depth.

[0049] In the embodiment, the increasing amplitude of the flow is slowed down with the increase of the water depth, and the increasing amplitude of the flow is also slowed down with the increase of the water depth, so the degree of slowing down of the increasing amplitude of the flow is used to measure the danger degree of the debris flow.

[0050] Specifically, in the embodiment, the degree of slowing down of the increasing amplitude of the flow can be calculated by the following sub-steps: The current fluid roughness is determined according to the current water depth monitoring value and the current flow rate monitoring value, and the degree of slowing down of the increasing amplitude of the current flow is determined according to the current fluid roughness and the flood roughness. The warning level is determined according to the degree of slowing down of the increasing amplitude of the current flow.

[0051] Specifically, the current flow monitoring value can be determined according to the current water depth monitoring value and the current flow rate monitoring value. The current theoretical value of the flood flow is calculated according to the current water depth monitoring value and the flood roughness. The degree of slowing down of the increasing amplitude of the current flow is determined according to the current theoretical value of the flood flow and the current flow monitoring value.

[0052] In the embodiment, if the internal roughness is ignored, n = n1, and the flow calculated based on the water depth monitoring value by the above formula (2) is the theoretical value of the flood flow Q1.

[0053] In the embodiment, the degree of slowing down of the increasing amplitude of the flow is calculated by the following formula: γ= Q1 / Q2= n2 / n1(5) Wherein, Q1 represents the theoretical value of the flood flow calculated based on the water depth monitoring value, and Q2 represents the flow of the debris flow, i.e. the current flow monitoring value.

[0054] In the embodiment, the current flow monitoring value can be directly monitored, or can be determined according to the current water depth monitoring value and the current flow rate monitoring value.

[0055] In the embodiment, the degree of slowing down of the increasing amplitude of the flow is determined according to the roughness corresponding to the high-density debris flow.

[0056] Specifically, γ0= n2 / n1. Wherein n2 represents the empirical value of the roughness corresponding to the high-density debris flow.

[0057] In the embodiment, the degree of slowing down of the increasing amplitude of the flow is determined based on the above formula (1) and Figure 2It can be seen that the corresponding fluid roughness can be obtained based on the flow rate monitoring value and the water depth monitoring value, and the fluid roughness includes external roughness and internal roughness in the development process of the debris flow. In the embodiment of the present application, the mountain torrent roughness is taken as the external roughness, and the roughness caused by the internal friction of the debris flow in the development process of the debris flow is taken as the internal roughness. Therefore, it can be understood that with the development of the debris flow, the internal roughness increases, the flow roughness increases, and the increasing amplitude slows down.

[0058] Further, the embodiment of the present application proposes that the increasing amplitude slowing down degree of the flow can be calculated by the following sub-steps: determining the current fluid roughness according to the current water depth monitoring value and the current flow rate monitoring value, and determining the current flow increasing amplitude slowing down degree according to the current fluid roughness and the mountain torrent roughness.

[0059] In the embodiment of the present application, γ represents the degree of flow increasing amplitude slowing down caused by the increase of internal roughness. Correspondingly, γ can reflect the density change of the debris flow that is currently developing, that is, the larger γ is, the larger the fluid soil content is, the larger the density is, and the greater the harm is.

[0060] Further, in the embodiment of the present application, the above step S104 includes the following sub-steps: S1041, in the case that the current water depth monitoring value is greater than the critical water depth, and the current flow increasing amplitude slowing down degree is greater than the flow increasing amplitude slowing down degree threshold, determining that the warning level is a first-level warning; S1042, in the case that the current water depth monitoring value is greater than the critical water depth, and the current flow increasing amplitude slowing down degree is less than or equal to the flow increasing amplitude slowing down degree threshold, determining that the warning level is a second-level warning; S1043, in the case that the current water depth monitoring value is less than or equal to the critical water depth, and the current flow increasing amplitude slowing down degree is greater than the flow increasing amplitude slowing down degree threshold, determining that the warning level is a third-level warning; S1044, in the case that the current water depth monitoring value is less than the critical water depth, and the current flow increasing amplitude slowing down degree is less than the flow increasing amplitude slowing down degree threshold, determining that the warning level is a fourth-level warning.

[0061] In the embodiment of the present application, the warning levels gradually decrease from the first-level warning to the fourth-level warning.

[0062] Specifically, in the embodiment of the present application, by setting the H0 and γ0 thresholds corresponding to the debris flow, the following warning levels are formed: High-risk level: H>H0, γ>γ0, which represents that the fluid flow and the density are both above the threshold, and the debris flow with large flow and high density is the most dangerous.

[0063] Middle risk level: H > H0, γ ≤ γ0, representing that the fluid flow is larger, but the density is smaller, and the risk level is second.

[0064] Low risk level: H ≤ H0, γ > γ0, representing that the fluid flow is smaller, but the density is larger, and the risk is lower.

[0065] No risk level: H ≤ H0, γ ≤ γ0, representing that the fluid flow and the density are both smaller, representing a low-risk mountain torrent or a non-hazardous fluid.

[0066] Therefore, in the embodiment of the present application, by changing the water depth H and the flow increase amplitude reduction degree γ, the risk level of the disaster can be effectively evaluated.

[0067] In the embodiment of the present application, the change degree of the mountain torrent debris flow risk can also be further evaluated according to the change trend of the fluid parameters, to provide a reference for early warning and forecasting, specifically, the method further comprises the following steps: S107, a first flow increase amplitude reduction degree corresponding to the first water depth monitoring value is calculated according to the relationship curve between the flow and the water depth and the roughness of the flood and the debris flow.

[0068] S108, a second flow increase amplitude reduction degree corresponding to the first water depth monitoring value is calculated according to the relationship curve between the flow and the water depth and the roughness of the flood and the debris flow.

[0069] S109, a risk change amplitude is determined according to the first flow increase amplitude reduction degree and the second flow increase amplitude reduction degree, and the first water depth monitoring value and the second water depth monitoring value, and a risk change early warning prompt is output based on the risk change amplitude.

[0070] Specifically, in the embodiment of the present application, the risk change amplitude can be calculated by the following formula: λ = ΔH×a+Δγ×b(6) Wherein, λ represents the risk change amplitude, ΔH represents the difference between the second water depth monitoring value and the first water depth monitoring value, Δγ represents the difference between the second flow increase amplitude reduction degree and the first flow increase amplitude reduction degree, and a and b respectively represent the weight of the water depth and the flow increase amplitude reduction degree, which can be determined according to the empirical value.

[0071] Specifically, H increases, and γ increases, representing that the fluid flow and the density increase simultaneously, and the risk increases sharply. H increases, but γ decreases, representing that the fluid flow increases, but the density decreases, and the risk changes, which may increase. H decreases, but γ increases, representing that the fluid flow decreases, but the density increases, and the risk changes, which may increase. H and γ both decrease, representing that the fluid flow decreases, and the density decreases, and the risk decreases.

[0072] It can be seen that the greater the lambda, the greater the possibility of the fluid danger increasing sharply, and vice versa, the smaller the lambda, the lower the fluid danger. Such a judgment method can reflect the change trend of the fluid danger degree on the one hand, and can also reflect the change of the fluid property on the other hand. Therefore, based on the change range of the danger, the future change of the fluid property can be judged, and the prediction function is realized. At the same time, the required parameters such as the flow rate and the water depth of a specific section are obtained by actual monitoring, and are easy to obtain accurately.

[0073] In the embodiment of the present application, the data monitored during the disaster development process of the mountain torrent converted to the debris flow that has occurred in the target river basin can be used as historical monitoring data, which can include: historical flow rate monitoring values corresponding to historical water depth monitoring values. Similarly, the simultaneously monitored historical water depth monitoring values and historical flow rate monitoring values are used as a group of historical monitoring data. The historical monitoring data is analyzed by using the above method, and the critical water depth is determined. Further, the flow increase amplitude reduction degree threshold value is determined by using the historical debris flow disaster situation, specifically, the historical water depth monitoring values and the historical flow rate monitoring values obtained when the historical debris flow disaster is serious are used to determine the corresponding debris flow roughness, and then the flow increase amplitude reduction degree threshold value is determined. Correspondingly, after the mountain torrent occurs, the current monitoring data is obtained from the river section where the historical monitoring data is obtained, the relationship between the current water depth monitoring value and the critical water depth is judged, and the warning level is output according to the relationship between the current flow increase amplitude reduction degree and the flow increase amplitude reduction degree threshold value.

[0074] In the embodiment of the present application, the relationship between the water depth and the flow rate is used to calculate the change of the fluid roughness, the warning level is set according to the relationship between the roughness and the water depth and the change trend thereof, the trend of the fluid change is judged, and thus the debris flow warning and prediction technical scheme based on the relationship between the fluid parameters is realized.

[0075] In the embodiment of the present application, the coupling relationship between the fluid roughness and the flow is established by using the key parameters such as the water depth and the flow rate obtained by actual monitoring, the change trend of the fluid characteristics is fused, and a multi-parameter and multi-level disaster warning model is constructed. In the embodiment of the present application, the property change of the fluid can be identified by using the parameters such as the water depth and the roughness, the classification discrimination of the mountain torrent and the debris flow is realized, and the possible development trend and the danger degree thereof are predicted accordingly. Compared with the prior art method, the present application fully utilizes the coupling relationship between the multi-source monitoring data, improves the disaster type identification and prediction accuracy and reliability, and has high engineering practical value and popularization prospect.

[0076] Compared with the related art, the embodiment of the present application has the following beneficial effects: (1) In the related art, the debris flow early warning is generally based on a single parameter to set a warning threshold, which has a single function and a large error. The embodiment of the present application realizes the early warning method based on flow and roughness through the relationship between the actually monitored multiple parameters (flow rate and water depth), and simultaneously predicts the multiple parameters and multiple levels of the debris flow occurrence threshold and flow.

[0077] (2) In the related art, it is difficult to consider the change of fluid properties in the debris flow prediction and early warning. The embodiment of the present application identifies the change of fluid properties through the parameters such as water depth and roughness, can distinguish between mountain torrents and debris flows, and can predict the change trend of fluid hazards according to the change trend of parameters.

[0078] In summary, the technical scheme provided by the embodiment of the present application is not only dependent on a single monitoring parameter, but also based on the relationship between multiple parameters such as water depth, flow rate and roughness, and establishes a multi-parameter and multi-index early warning level system. This method can identify the change of fluid properties and predict the change trend of fluid hazards.

[0079] Based on the same inventive concept, the embodiment of the present application also provides a mountain torrent and debris flow multi-parameter prediction device based on roughness relationship, as shown in Figure 4 The structure block diagram of the mountain torrent and debris flow multi-parameter prediction device based on roughness relationship provided by the embodiment of the present application is shown, and specifically, the device comprises: The parameter acquisition module 401 is configured to acquire multiple historical water depth monitoring values and corresponding multiple historical flow rate monitoring values of a target flow field. The parameter acquisition module 402 is configured to acquire multiple historical water depth monitoring values and corresponding multiple historical flow rate monitoring values of a target flow field. The critical water depth determination module 403 is configured to determine the critical water depth-flow rate point and critical roughness of the conversion of flood to debris flow according to the historical water depth monitoring values and corresponding historical flow rate monitoring values. The relationship curve determination module 404 is configured to calculate the relationship curves between flow rate and water depth and roughness of flood and debris flow, respectively, according to the relationship between flow rate and water depth and roughness. The early warning module 405 is configured to obtain the critical water depth and critical roughness, and realize the early warning of debris flow and determine the early warning level by monitoring the relationship between the water depth, roughness and the critical water depth-flow rate point.

[0080] Optionally, the device further comprises: a threshold output module configured to determine a critical flow threshold of the mountain torrent and the debris flow based on the critical water depth and the corresponding flow rate monitoring value according to a formula Q0=V0H0L, and output the critical water depth and the critical flow threshold; wherein Q0represents the critical flow threshold, and the unit is cubic meters per second; L represents a river cross-sectional width of a target river basin, H0represents the critical water depth, and V0represents the corresponding flow rate monitoring value.

[0081] Optionally, the relationship curve determination module 404 is configured to: According to the following formula: Q = V H L=(1 / n)H 5 / 3 S 1 / 2 L; Wherein Q represents the flow, L represents the cross-sectional width of the river, n represents the roughness, H represents the water depth, and S represents the gradient of the river. The relationship curves between the flow and the water depth and the roughness of the flood and the debris flow are calculated respectively.

[0082] Optionally, the device further comprises a flow increase amplitude deceleration degree determination module configured to determine a current fluid roughness according to a current water depth monitoring value and a current flow rate monitoring value, determine a current flow increase amplitude deceleration degree according to the current fluid roughness and the mountain torrent roughness, and determine a warning level according to the current flow increase amplitude deceleration degree; the flow increase amplitude deceleration degree represents a degree of flow increase amplitude deceleration caused by the increase of the internal roughness of the debris flow.

[0083] Optionally, the prediction module 404 is configured to: determine the warning level as a first-level warning when the current water depth monitoring value is greater than the critical water depth and the current flow increase amplitude deceleration degree is greater than a flow increase amplitude deceleration degree threshold; determine the warning level as a second-level warning when the current water depth monitoring value is greater than the critical water depth and the current flow increase amplitude deceleration degree is less than or equal to the flow increase amplitude deceleration degree threshold; determine the warning level as a third-level warning when the current water depth monitoring value is less than or equal to the critical water depth and the current flow increase amplitude deceleration degree is greater than the flow increase amplitude deceleration degree threshold; determine the warning level as a fourth-level warning when the current water depth monitoring value is less than or equal to the critical water depth and the current flow increase amplitude deceleration degree is less than or equal to the flow increase amplitude deceleration degree threshold.

[0084] Optionally, the device further comprises: The dangerous change early warning prompt module is configured to: calculate a first flow increase amplitude reduction degree corresponding to the first water depth monitoring value according to a relationship curve between flow and water depth and roughness of flood and debris flow; calculate a second flow increase amplitude reduction degree corresponding to the first water depth monitoring value according to the relationship curve between flow and water depth and roughness of flood and debris flow; the flow increase amplitude reduction degree represents a degree of flow increase amplitude reduction caused by the increase of the internal roughness of the debris flow; determine a dangerous change amplitude according to the first flow increase amplitude reduction degree and the second flow increase amplitude reduction degree, and the first water depth monitoring value and the second water depth monitoring value; and output a dangerous change early warning prompt based on the dangerous change amplitude.

[0085] Based on the same inventive concept, the embodiments of the present application also provide an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the mountain torrent and debris flow multi-parameter prediction method based on the roughness relationship according to any one of the above embodiments when executed.

[0086] Based on the same inventive concept, the embodiments of the present application also provide a computer readable storage medium, which stores a computer program, wherein the program implements the steps of the mountain torrent and debris flow multi-parameter prediction method based on the roughness relationship according to any one of the above embodiments when executed by a processor.

[0087] Based on the same inventive concept, the embodiments of the present application provide a computer program product, comprising a computer program / instruction, wherein the computer program / instruction implements the steps of the mountain torrent and debris flow multi-parameter prediction method based on the roughness relationship according to any one of the above embodiments when executed by a processor.

[0088] Each of the embodiments in the specification is described in a progressive manner, and each embodiment focuses on the difference from other embodiments, and the same and similar parts between the embodiments can be referred to each other.

[0089] Although the preferred embodiments of the embodiments of the present application have been described, those skilled in the art can make further changes and modifications to the embodiments once they know the basic inventive concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the embodiments of the present application.

[0090] Finally, it is to be understood that the phraseology or terminology such as "first" and "second" etc. used herein is merely intended to differentiate one entity or operation from another entity or operation, without necessarily requiring or implying any actual such relationship or order between such entities or operations. Moreover, the terms "comprising", "including", or any other closure, are intended to cover the non-exclusive inclusion such that a process, method, article, or apparatus that comprises a list of elements does not include those elements alone but can include other elements not expressly listed or even include elements inherent in such process, method, article, or apparatus. Without more limitations, the element defined by the statement "comprising a" does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes the element.

[0091] The above describes in detail a mountain torrent and debris flow multi-parameter prediction method based on roughness relationship provided by the present application. The principle and implementation mode of the present application are described by applying specific examples. The above description of the embodiments is only used to help understand the method of the present application and its core idea. Meanwhile, for those skilled in the art, according to the idea of the present application, the specific implementation mode and application range will be changed. In view of the above, the content of the specification should not be understood as a limitation of the present application.

Claims

1. A multi-parameter forecasting method for mountain torrents and debris flows based on roughness relationship, characterized in that: The method comprises: Obtain multiple historical water depth monitoring values ​​and corresponding multiple historical flow velocity monitoring values ​​of the target watershed; Based on the historical water depth monitoring values ​​and the corresponding historical flow velocity monitoring values, the critical water depth-flow velocity point and critical roughness ratio at which floods turn into debris flows are determined; According to the relationship between flow rate, water depth and roughness, the relationship curves between flow rate, water depth and roughness of flood and debris flow are calculated respectively; After obtaining the critical water depth and critical roughness, the relationship between water depth, roughness and critical water depth-velocity point is monitored to achieve early warning of debris flow and determine the warning level.

2. The multi-parameter prediction method for mountain torrents and debris flows based on roughness relationship according to claim 1, characterized in that: The method further comprises: Based on the critical water depth and the corresponding flow velocity monitoring value, the following formula is used to determine the critical flow threshold for flash floods and debris flows: Q0 = V0 H0L; Among them, Q0 represents the critical flow threshold, in cubic meters per second; L represents the cross-sectional width of the river channel in the target basin; H0 represents the critical water depth; and V0 represents the corresponding flow velocity monitoring value. The critical water depth and the critical flow threshold are output.

3. The multi-parameter prediction method for mountain torrents and debris flows based on roughness relationship according to claim 1, characterized in that: Based on the relationship between flow, water depth and roughness, the relationship curves between flow, water depth and roughness of floods and debris flows are calculated, including: According to the following formula: Q = V H L=(1 / n)H 5 / 3 S 1 / 2 L; Among them, Q represents the flow rate, L represents the cross-sectional width of the river channel, n represents the roughness, H represents the water depth, and S represents the gradient of the river channel. The relationship curves between the flow rate of floods and debris flows and water depth and roughness are calculated respectively.

4. The multi-parameter forecasting method for mountain torrents and debris flows based on roughness relationship according to any one of claims 1 to 3, characterized in that: The method further comprises: determining a current fluid roughness based on a current water depth monitoring value and a current flow velocity monitoring value, and determining a degree of slowing down the current flow rate increase based on the current fluid roughness and the flash flood roughness; the degree of slowing down the flow rate increase represents the degree to which the flow rate increase is slowed down due to an increase in the internal roughness of the debris flow; The warning level is determined based on the degree to which the current traffic increase slows down.

5. The multi-parameter prediction method for mountain torrents and debris flows based on roughness relationship according to claim 4 is characterized in that: By monitoring the relationship between water depth, roughness and critical water depth-velocity point, early warning of debris flow is achieved and the warning level is determined, including: When the current water depth monitoring value is greater than the critical water depth and the current flow rate increase reduction degree is greater than the flow rate increase reduction degree threshold, the warning level is determined to be a level one warning; When the current water depth monitoring value is greater than the critical water depth and the current flow rate increase reduction degree is less than or equal to the flow rate increase reduction degree threshold, the warning level is determined to be a level 2 warning; When the current water depth monitoring value is less than or equal to the critical water depth, and the current flow rate increase reduction degree is greater than the flow rate increase reduction degree threshold, the warning level is determined to be a level three warning; When the current water depth monitoring value is less than or equal to the critical water depth, and the current flow rate increase reduction degree is less than or equal to the flow rate increase reduction degree threshold, the warning level is determined to be a level 4 warning.

6. The multi-parameter forecasting method for mountain torrents and debris flows based on roughness relationship according to claim 1, characterized in that: The method further comprises: The degree of slowing down of the first flow increase corresponding to the first water depth monitoring value is calculated based on the relationship curve between the flow of floods and debris flows and the water depth and roughness; The degree of slowing down of the second flow increase corresponding to the first water depth monitoring value is calculated based on the relationship curve between the flow rate of floods and debris flows and the water depth and roughness; The dangerousness change range is determined according to the first flow rate increase slowdown degree and the second flow rate increase slowdown degree and the first water depth monitoring value and the second water depth monitoring value, and a dangerousness change warning prompt is output based on the dangerousness change range.

7. A multi-parameter forecasting device for mountain torrents and debris flows based on roughness relationship, characterized in that: The device comprises: A parameter acquisition module is used to obtain multiple historical water depth monitoring values ​​and corresponding multiple historical flow velocity monitoring values ​​of the target basin; The critical water depth determination module is used to determine the critical water depth-flow velocity point and critical roughness at which a flood turns into a debris flow based on historical water depth monitoring values ​​and corresponding historical flow velocity monitoring values; A relationship curve determination module is used to calculate the relationship curves between the flow rate, water depth and roughness of floods and debris flows respectively based on the relationship between the flow rate, water depth and roughness; The early warning module is used to obtain the critical water depth and critical roughness, and then to provide early warning of debris flow and determine the warning level by monitoring the relationship between water depth, roughness and critical water depth-flow velocity point.

8. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the computer program, the multi-parameter forecasting method for mountain torrents and debris flows based on roughness relationship described in any one of claims 1 to 6 is implemented.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the multi-parameter forecasting method for mountain torrents and debris flows based on roughness relationship described in any one of claims 1 to 6 is implemented.

10. A computer program product comprising a computer program / instructions, characterized in that When the computer program / instruction is executed by a processor, the steps of the multi-parameter forecasting method for mountain torrents and debris flows based on roughness relationship described in any one of claims 1 to 6 are implemented.

Images