CN107843713B - Artificial rainfall simulation method for debris flow start-up test - Google Patents

Abstract

The invention discloses an artificial rainfall simulation method for a debris flow start test, which comprises an artificial rainfall device, a rainfall monitoring device and a control device, wherein the artificial rainfall device comprises a water tank, a water pump, a rainfall bracket and a rainfall sprayer, the rainfall sprayer is arranged on the rainfall bracket, the rainfall sprayer is connected with the water tank through a water pipeline, the water tank is connected with the water pump, the rainfall monitoring device records the actual rainfall amount, the soil water content, the soil displacement and the stretching amount of a stretching sensor and sends the detected data to the control device, and the control device judges whether debris flow occurs according to the collected data and records the slope runoff, the runoff inside the slope body, the soil body creep deformation condition and the time for forming the debris flow in the debris flow occurrence process. The device has the advantages of simple structure, convenient operation, capability of simulating the debris flow detection process under different rainfall types, quick and accurate detection result and provision of basis for debris flow prediction.

Description

Artificial rainfall simulation method for debris flow start-up test

technical field

The invention relates to the technical field of debris flow start-up test, in particular to an artificial rainfall simulation method for debris flow start-up test.

Background technique

Debris flow is a solid-liquid two-phase fluid filled with a large number of sediments, stones and boulders. It has the characteristics of sudden outbreak, strong transport and impact burying ability, and great destructive power. The nature of debris flow determines its formation needs. Adequate water source. The source of water that causes debris flow in my country mainly comes from torrential rain, which is manifested as a disaster when the rainfall reaches a certain critical rainfall value. Therefore, the determination of critical rainfall is of great significance for studying the formation mechanism of debris flow, analyzing and predicting the characteristics of future activities of debris flow, and guiding the design of debris flow prevention and control projects.

Observation and statistical data show that there is a critical rainfall threshold for the occurrence of single-ditch debris flows and regional debris flows. The threshold can be determined according to the historical disaster events of debris flows and influencing factors such as landforms, geology, topography, soil, vegetation, etc. or experimental methods. In recent years, the research on rainfall conditions of rainfall-type debris flow and disaster prediction and forecasting based on rainfall factors have attracted the attention of many debris flow scholars at home and abroad, and have become a hot issue in debris flow research in the past ten years. Experiments and statistics on the relationship between rainfall indicators such as heavy rainfall, 1h rainfall intensity, 24h rainfall, effective rainfall in the previous n days and the occurrence of debris flow, established a series of prediction models based on rainfall and rainfall intensity, which greatly promoted the prediction of debris flow disasters The solution of forecasting problems has made contributions to our country's disaster prevention and mitigation work.

However, most of the existing debris flow prediction models are established based on statistical data. Debris flows are mostly found in remote mountainous areas where monitoring data is scarce. Many existing models cannot meet the needs of disaster prevention and mitigation. In situ test or model test, and then determine the rainfall threshold for the initiation of debris flow in each area according to the underlying surface conditions. Combined with the experimental phenomenon, the characteristics of debris flow initiation, debris flow scale and accumulation characteristics can be analyzed, the ability of debris flow to cause disasters, and the potential scope of influence can be evaluated. And establish a debris flow start-up model to provide a basis for future debris flow prediction. The existing debris flow initiation artificial rainfall device has a relatively simple structure, which cannot simulate the influence of regional point rainstorm on the initiation of debris flow, and the rainfall conditions cannot be regulated. The accuracy cannot meet the needs of disaster prevention and mitigation.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide an artificial rainfall simulation method for debris flow startup test, which can simulate different rainfall types, and establish debris flow startup models under different rainfall types, so as to provide a basis for debris flow prediction and prediction.

To achieve the above object, the present invention adopts the following technical solutions:

An artificial rainfall simulation system for a mud-rock flow start-up test, including an artificial rainfall device, a rainfall monitoring device and a control device, the artificial rainfall device includes a water tank, a water pump, a rainfall support and a rainfall sprinkler, the rainfall sprinkler is arranged on the rainfall support, and the rainfall sprinkler is transported through the pipeline. The water pipeline is connected with the water tank, and the water tank is connected with the water pump; the rainfall monitoring device adopts a rain gauge, the rain gauge is arranged under the rain sprinkler, and the rain gauge is connected with the control device.

Preferably, the rainfall monitoring device further comprises a fixed rod, a measuring rod, a moisture content sensor and a displacement sensor, the fixed rod is inserted into the soil layer outside the rainfall area, a tensile sensor is arranged on the upper part of the fixed rod, and the measuring rod is inserted into the rainfall area In the inner soil layer, the top of the measuring rod is connected to the tensile sensor through the steel wire. The water content sensor and the displacement sensor are all buried in the soil layer within the rainfall range. connected to the control unit.

Preferably, the rainfall monitoring device further includes a camera, the camera is arranged outside the rainfall range through the rainfall support, and the camera is connected to the control device.

Preferably, the rain support includes a base, a lifting oil cylinder, a support plate, a first adjusting oil cylinder and a second adjusting oil cylinder. The lower end of an adjustment cylinder is hinged with the support plate, and the other end is connected with the rain sprinkler. The middle of the first adjustment cylinder is hinged with one end of the second adjustment cylinder, and the other end of the second adjustment cylinder is hinged with the support plate. The expansion and contraction of the oil cylinder can change the height of the rain sprinkler, and the inclination angle between the rain sprinkler and the horizontal plane can be changed through the expansion and contraction of the second adjusting oil cylinder.

Preferably, the water tank includes a main water tank and a plurality of sub-water tanks, the main water tank is respectively connected to each sub-water tank through a water delivery pipeline, there are also a plurality of the rainfall supports and rainfall sprinklers, and each rainfall sprinkler heads are respectively arranged on the rainfall support, each The water distribution tanks are respectively connected with the rainfall sprinklers through water delivery pipes.

Preferably, a pressure regulating valve is provided at the water outlet of the main water tank and each water distribution tank, and a pressure gauge and an exhaust valve are provided on both the main water tank and the water distribution tank.

Preferably, the control device includes a signal processing unit and a single-chip microcomputer, the input ends of the signal processing unit are respectively connected with the output ends of the rain gauge, the camera, the tensile sensor, the water content sensor, the displacement sensor and the pressure gauge, and the output ends of the signal processing unit are respectively connected. The end is connected with the single-chip microcomputer, and the output end of the single-chip microcomputer is respectively connected with the pressure regulating valve, the exhaust valve, the lifting oil cylinder, the first regulating oil cylinder and the second regulating oil cylinder.

Preferably, a remote server is also included, and the remote server communicates with the microcontroller via wireless.

The method for artificial rainfall simulation using the above-mentioned debris flow startup test artificial rainfall simulation system includes the following steps in sequence:

(1) Select a suitable slope as the test site in the field, use the compass to measure the slope of the slope, and determine the soil density, early moisture content and particle composition characteristics of the slope soil;

(2) Delineate the test area, arrange rainfall supports, and adjust the direction of rainfall sprinklers to ensure uniform rainfall;

(3) Arrange rain gauges, measuring rods, moisture content sensors and displacement sensors in the rainfall area, and arrange fixed rods, tensile sensors and cameras outside the rainfall area;

(4) Turn on the artificial rainfall device, rainfall monitoring device and control device, and start the test;

(5) Record the actual rainfall, soil moisture content, soil displacement, and tensile sensor tension respectively, and send the detected data to the control device. The screen is used to judge whether debris flow occurs, and the single chip computer records the slope runoff, the internal runoff of the slope, the creep deformation of the soil body and the time when the debris flow is formed during the occurrence of the debris flow;

(6) Adjust the opening of the pressure regulating valve to adjust the amount of rain sprayed by the rain sprinkler to simulate different rainfall conditions;

(7) Repeat steps (5) and (6) to record the occurrence process of debris flow under different rainfall conditions, and establish the slope runoff, internal slope runoff, and soil creep deformation during the occurrence of debris flow under different rainfall conditions. conditions and when the mudslides formed.

The present invention simulates the rainfall through the artificial rainfall device, monitors the soil layer changes under different rainfall through the rainfall monitoring device, and records the slope runoff, the internal runoff of the slope body, the creep deformation of the soil body during the occurrence of debris flow through the control device, and the The formation time of the debris flow can establish the debris flow startup model under different rainfall types; by adjusting the opening of the pressure regulating valve, the pressure in the water tank can be adjusted, and the corresponding pressure can be set according to the regional underlying surface conditions and rainfall characteristics to control rainfall. Type, by adjusting the internal pressure value of the water distribution tank, it is possible to simulate the phenomenon of regional point rainstorm concentration. By closing one or more of the water distribution tanks, the rainfall process in strong wind weather can be simulated, and the type of storm can also be simulated by overlapping rainfall areas, and the simulation results Fast and accurate; the rainfall monitoring device can collect soil changes in real time, so as to accurately detect the start time and formation process of debris flow, and provide a basis for debris flow prediction and prediction.

Description of drawings

Fig. 1 is the structural representation of the present invention;

Fig. 2 is the structural schematic diagram of the rain support according to the present invention;

Fig. 3 is the principle block diagram of the present invention;

FIG. 4 is a schematic structural diagram of the pressure regulating valve in the present invention.

Detailed ways

The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present invention.

As shown in Figures 1 to 4, the artificial rainfall simulation system of the debris flow start-up test according to the present invention includes an artificial rainfall device, a rainfall monitoring device, a control device and a remote server. The artificial rainfall device is used to realize artificial rainfall, and rainfall monitoring The device is used to monitor rainfall and soil layer changes, the control device is used to control the work of the artificial rainfall device and the rainfall monitoring device, and the control device communicates with a remote server via wireless.

The artificial rainfall device includes a motor 1, a water tank, a water pump 2, a rainfall support 11 and a rainfall nozzle 12. The water tank includes a general water tank 4 and several sub-water tanks 8. In this embodiment, there are four sub-water tanks 8, and the main water tank 4 is passed through the water pump. 2 is connected to the motor, the main water tank 4 is also connected to the respective water distribution tanks 8 through the water delivery pipeline 3, and there are also four rainfall supports 11 and rainfall sprinklers 12. The water delivery pipeline 3 is connected with the rainfall sprinkler 12, the water delivery pipeline 3 at the water outlet of the total water tank 4 and each water distribution tank 8 is provided with a pressure regulating valve 7, and the total water tank 4 and the water distribution tank 8 are provided with pressure gauges 5 and 8. The exhaust valve 6, by adjusting the opening of the pressure regulating valve 7, can adjust the water pressure of the main water tank 4 and each sub-water tank 8, thereby adjusting the rainfall, and the pressure gauge 5 is used to detect the total water tank 4 and each sub-water tank 8. The pressure value, the exhaust valve 6 is used to adjust the pressure in the main water tank 4 and the water distribution tank 8, so as to avoid excessive pressure fluctuations in the water tank and affect the test. The pressure gauge is connected to the input end of the control device, and the output end of the control device is respectively It is connected to the pressure regulating valve 7 and the exhaust valve 6 .

The pressure regulating valve 7 includes a valve body 701, a cavity 712 is arranged inside the valve body 701, a mounting ring 702 is arranged inside the liquid outlet end of the valve body 701, and a regulating chamber is arranged on the side wall of the liquid inlet end of the valve body. 703, a stud 704 is threadedly connected to the other side wall corresponding to the adjustment chamber 703 at the liquid inlet end of the valve body. The inner diameter of the adjustment chamber 703 is adjusted, and the adjustment column 706 is located in the adjustment chamber 703; a spring 707 is installed on the mounting ring 702, the other end of the spring 707 is connected with a conical baffle plate 709, and three support rods 708 are fixed at the bottom of the conical baffle plate 709. , the bottom of the support rod 708 is slidably connected with the side wall of the cavity 712 . A pressure sensor 710 is disposed in the liquid inlet end of the valve body 701 , and the pressure sensor 710 is electrically connected to the display screen 711 . Through the reading of the pressure sensor 710 displayed on the display screen, the screw-in and screw-in distance of the adjustment column 706 in the adjustment bin 703 can be adjusted by the handle, and then the pressure can be adjusted; when the pressure control valve 7 is closed, it is subjected to the elastic force of the spring 707. , the conical baffle 709 will block the water inlet end of the cavity 712 to prevent the liquid from flowing back, and the liquid flowing back from the water inlet end of the pressure regulating valve 7 will flush the pressure regulating valve 7 .

The rainfall support includes a base 11-1, a lift cylinder 11-2, a support plate 11-3, a first adjustment cylinder 11-5 and a second adjustment cylinder 11-4. The support plate 11-3 passes through the lift cylinder 11-2 and the base 11. -1 is connected, the support plate 11-3 is moved up and down by the expansion and contraction of the lifting cylinder 11-2, the lower end of the first adjusting oil cylinder 11-5 is hinged with the support plate 11-3, and the other end is connected to the rain sprinkler 12, and the first adjusting oil cylinder 11- 5 is hinged with one end of the second adjusting oil cylinder 11-4, and the other end of the second adjusting oil cylinder 11-4 is hinged with the support plate 11-3. To change the height of the rain shower head 12 , the inclination angle between the rain shower head 12 and the horizontal plane can be changed through the expansion and contraction of the second adjusting oil cylinder 11 - 4 . The lift cylinder 11-2, the first adjustment cylinder 11-5 and the second adjustment cylinder 11-4 are respectively connected to the control device, and the lift cylinder 11-2, the first adjustment cylinder 11-5 and the second adjustment cylinder 11-4 are all The structure and working principle of the existing oil cylinder will not be repeated. In addition, the rain shower head 12 is detachably connected to the first adjusting oil cylinder 11-5, and the rain shower head 12 of different specifications can be replaced during use, thereby simulating different types of rain intensities from light rain to heavy rain.

The rainfall monitoring device includes a rain gauge 10, a fixed rod, a measuring rod, a moisture content sensor, a displacement sensor and a camera 14. The fixed rod is inserted into the soil layer outside the rainfall area, a tensile sensor is arranged on the upper part of the fixed rod, and the measuring rod is inserted into the rainfall area. In the soil layer, the top of the measuring rod is connected to the tensile sensor through the steel wire, the moisture content sensor and the displacement sensor are buried in the soil layer within the rainfall range, the camera 14 is set outside the rainfall range through the camera bracket 13, and the rain gauge 10 is set at the Below the rain shower head 12, the output ends of the rain gauge 10, the tensile sensor, the moisture content sensor, the displacement sensor and the camera 14 are all connected to the control device.

The control device includes a signal processing unit and a single-chip microcomputer. The input end of the signal processing unit is respectively connected with the output end of the rain gauge 10, the camera 14, the tensile sensor, the moisture content sensor, the displacement sensor and the pressure gauge 5, and the output end of the signal processing unit is connected to the output end of the pressure gauge 5. The single-chip microcomputer is connected, and the output end of the single-chip microcomputer is connected with the pressure regulating valve 7 and the exhaust valve 6 respectively.

In this embodiment, the motor 1 adopts a 3kw gasoline generator, the water pump 2 adopts a 70-meter head variable frequency constant pressure water pump, the total height of the rainfall support 11 is 3.5 meters, the water delivery pipeline 3 adopts a high-pressure rubber water pipe, and the pressure regulating valve 7 adopts The connection between solenoid valve, pressure regulating valve 7 and water pipeline 3 is treated with sealing tape to prevent water leakage

A method for artificial rainfall simulation using a debris flow start-up test artificial rainfall simulation system, comprising the following steps in sequence:

(1) Select a suitable slope as the test site in the field, use the compass to measure the slope of the slope, and determine the soil density, early moisture content and particle composition characteristics of the slope soil;

Determination of soil density, early moisture content and particle composition characteristics of slope soil can select rainfall according to the characteristics of slope soil, and at the same time facilitate the analysis of debris flow occurrence under different soil qualities.

(2) Delineate the test area, arrange the rainfall support 11, and adjust the direction of the rainfall sprinkler 12 to ensure uniform rainfall;

(3) Arrange rain gauge 10, measuring rod, moisture content sensor and displacement sensor in the rainfall area, and arrange fixed rod, tensile sensor and camera 14 outside the rainfall area;

(4) Turn on the artificial rainfall device, rainfall monitoring device and control device, and start the test;

(5) Record the actual rainfall, soil moisture content, soil displacement, and tensile sensor tension respectively, and send the detected data to the control device. The screen is used to judge whether debris flow occurs, and the single chip computer records the slope runoff, the internal runoff of the slope, the creep deformation of the soil body and the time when the debris flow is formed during the occurrence of the debris flow;

(6) Adjust the opening of the pressure regulating valve 7, thereby adjusting the amount of rain sprayed by the rain sprinkler 12, and simulate different rainfall conditions;

If there is a concentrated rainstorm or long-term strong wind and rain in the area, it can be controlled by adjusting the pressure in the water distribution tank 8, or the rainfall areas of the rain sprinklers 12 can be overlapped to simulate the rainfall process in the storm mode.

(7) Repeat steps (5) and (6) to record the occurrence process of debris flow under different rainfall conditions, and establish the slope runoff, internal slope runoff, and soil creep deformation during the occurrence of debris flow under different rainfall conditions. conditions and when the mudslides formed.

The invention has simple structure and convenient operation, can simulate different rainfall types, and can detect slope runoff, internal runoff of slope body, soil creep deformation and the time of formation of debris flow in the process of debris flow occurrence under different rainfall types. The detection results are fast and accurate, providing a basis for the prediction of debris flow.

Claims (3)

1. a debris flow startup test artificial rainfall simulation method, is characterized in that, adopts debris flow startup test artificial rainfall simulation system to simulate, and debris flow startup test artificial rainfall simulation system comprises artificial rainfall device, rainfall monitoring device and control device, and described artificial rainfall The device includes a water pump, a rainfall support, a rainfall sprinkler, a main water tank and several sub-water tanks. The water pump is connected to the main water tank through a water delivery pipe, the main water tank is connected to the sub-water tank through the water inlet pipe of the sub-water tank, and the rainfall sprinkler is connected to the sub-water tank through the water outlet pipe of the sub-water tank. Rainfall sprinklers are arranged on the rainfall support, the water inlet pipe of the water distribution tank and the water outlet pipe of the water distribution tank are provided with pressure control valves, and the main water tank and the water distribution tank are provided with pressure gauges and exhaust valves; the rainfall monitoring device adopts rainfall The rain gauge is arranged below the rain sprinkler, and the rain gauge is connected to the control device; the rainfall monitoring device also includes a fixed rod, a measuring rod, a moisture content sensor and a displacement sensor, and the fixed rod is inserted into the soil layer outside the rainfall area, A tensile sensor is arranged on the upper part of the fixed rod, the measuring rod is inserted into the soil layer in the rainfall area, and the top of the measuring rod is connected to the tensile sensor through a steel wire. The output ends of the tensile sensor, the moisture content sensor and the displacement sensor are all connected with the control device; the rainfall monitoring device further includes a camera, the camera is arranged outside the rainfall area through the rainfall support, and the camera is connected with the control device; the rain support includes a base , Lifting oil cylinder, support plate, first adjusting oil cylinder and second adjusting oil cylinder, the support plate is connected with the base through the lifting oil cylinder, and the support plate is lifted and lowered by the expansion and contraction of the lifting oil cylinder, and the lower end of the first adjusting oil cylinder is hinged with the support plate , the other end is connected to the rain sprinkler, the middle part of the first adjustment cylinder is hinged with one end of the second adjustment cylinder, the other end of the second adjustment cylinder is hinged with the support plate, and the height of the rain sprinkler can be changed through the expansion and contraction of the first adjustment cylinder and the lifting cylinder , the inclination angle between the rain sprinkler and the horizontal plane can be changed through the expansion and contraction of the second adjustment cylinder; the control device includes a signal processing unit and a single-chip microcomputer, and the input end of the signal processing unit is respectively connected with the rain gauge, the camera, the tensile sensor, the water content The output ends of the sensor, the displacement sensor and the pressure gauge are connected, the output end of the signal processing unit is connected with the single chip microcomputer, and the output ends of the single chip microcomputer are respectively connected with the pressure regulating valve, the exhaust valve, the lifting oil cylinder, the first regulating oil cylinder and the second regulating oil cylinder; The simulation method includes the following steps in sequence: (1) Select a suitable slope as the test site in the field, use the compass to measure the slope of the slope, and determine the density, early moisture content and particle composition characteristics of the slope soil; (2) Delineate the test area, arrange rainfall supports, and adjust the direction of rainfall sprinklers to ensure uniform rainfall; (3) Arrange rain gauges, measuring rods, moisture content sensors and displacement sensors in the rainfall area, and arrange fixed rods, tensile sensors and cameras outside the rainfall area; (4) Turn on the artificial rainfall device, rainfall monitoring device and control device, and start the test; (5) Record the actual rainfall, soil moisture content, soil displacement, and tensile sensor tension respectively, and send the detected data to the control device. The control device combines the collected data with the images captured by the camera. , judge whether debris flow occurs, and record slope runoff, internal slope runoff, and soil creep in the process of debris flow occurrence by single chip microcomputer shape and time of debris flow formation; (6) Adjust the opening of the pressure regulating valve to adjust the amount of rain sprayed by the rain sprinkler to simulate different rainfall conditions; (7) Repeat steps (5) and (6) to record the occurrence process of debris flow under different rainfall conditions, and establish the slope runoff, internal slope runoff, and soil creep deformation during the occurrence of debris flow under different rainfall conditions. Situation and formation of debris flow time. 2 . The artificial rainfall simulation method for a mud-rock flow start-up test according to claim 1 , wherein the pressure regulating valve comprises a valve body, the interior of the valve body is provided with a cavity, and the liquid outlet end of the valve body is provided with a cavity. 3 . Install the ring, the side wall of the liquid inlet end of the valve body is provided with an adjustment bin, the other side wall of the liquid inlet end of the valve body is threadedly connected with a stud, one end of the stud is connected with an adjustment column, and the other end is connected with a handle. The outer diameter is not greater than the inner diameter of the adjustment bin; a spring is installed on the installation ring, and the other end of the spring is connected with a conical baffle, the bottom of the conical baffle is fixed with three support rods, and the bottom of the support rod slides with the side wall of the cavity connect. 3. The artificial rainfall simulation method for a mud-rock flow start-up test as claimed in claim 1, wherein the method further comprises a remote server, and the remote server communicates with the single-chip microcomputer via wireless.

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