Full-life-cycle water seal safety evaluation method and device for underground water seal cave depot

Abstract

The invention discloses a water seal safety evaluation method and device for a full life cycle of an underground water-sealed cave depot, and the method comprises the steps: obtaining and analyzing first hydrological monitoring data and water curtain system experiment data during the construction period of the cave depot, and predicting a potential risk region; before the cave depot is operated, second hydrological monitoring data before the cave depot is operated are obtained and analyzed based on an air tightness experiment on the potential risk area; and during the operation period of the cave depot, monitoring third hydrological monitoring data and water curtain water supply system data of the potential risk area, and determining the overall risk level of the cave depot based on a pre-constructed water seal safety evaluation system according to the second hydrological monitoring data, the third hydrological monitoring data and the water curtain water supply system data. According to the method, the data of the whole life cycle of the cave depot can be monitored, correlation analysis is performed on the data to obtain the safety evaluation result, the risk of the water-sealed cave depot is recognized in time, the evaluation result is high in accuracy and reliability, operation is convenient, cost is low, and important reference data is provided for underground water-sealed engineering.

Description

Technical Field

[0001] The present invention relates to the technical field of underground water seal caverns, and in particular to a method and device for evaluating water seal safety over the entire life cycle of an underground water seal cavern. Background Art

[0002] Underground water-sealed petroleum caverns are characterized by large scale, multiple excavation surfaces, frequent cross-operations, and strict requirements for groundwater level control. It was found from the construction and operation of caverns that have been built at home and abroad that during construction, the surrounding rock mass in the structural fracture zone became unstable and collapsed, the groundwater level dropped and broke through the warning water level, and the blasting construction of the main cavern aggravated the surrounding rock damage and derived dense water diversion channels, all of which affected the construction and operation of underground water-sealed caverns to varying degrees. It can be seen that the realization of its function depends not only on the stability of the underground structure, but also on the safety of the cavern water seal. The risks exposed during the construction and operation of underground water-sealed petroleum caverns will often have serious consequences. Therefore, it is necessary to timely identify the water seal safety risks of underground water-sealed caverns and take corresponding risk response measures.

[0003] The water seal safety monitoring of the built underground water seal caverns mostly adopts single monitoring technology. For example, each data such as groundwater level, water inflow, surrounding rock fissure water pressure monitoring is analyzed separately to realize the monitoring of water seal safety. Summary of the invention

[0004] The water seal characteristics of underground oil reservoirs determine the complexity and difficulty of their monitoring technology. The inventors of this application have found that currently, single data monitoring technology is usually used to monitor the water seal safety of underground water seal caverns. The monitoring data is not deeply mined and utilized, and the correlation between data is not considered when analyzing the monitoring data. A safety monitoring and evaluation system with interrelated data has not been formed, which leads to poor accuracy of the monitoring results of the water seal safety of underground water seal caverns, and the risks of water seal caverns cannot be identified in time, and risk assessment and safety control cannot be effectively carried out. In short, the existing technology lacks systematic full life cycle management technology system support, which restricts the development of water seal safety monitoring work for underground water seal caverns. Therefore, it is necessary to create a set of full life cycle water seal safety monitoring and risk assessment methods to timely identify and control risk sources to ensure the safe construction of underground rock cavern reservoirs.

[0005] In view of the above problems, the present invention is proposed to provide a method and device for evaluating water seal safety during the entire life cycle of an underground water seal cavern that overcomes the above problems or at least partially solves the above problems.

[0006] In a first aspect, an embodiment of the present invention provides a method for evaluating water seal safety during the entire life cycle of an underground water seal cavern, including:

[0007] During the cavern construction, the first hydrological monitoring data and water curtain system experimental data are obtained, the data evolution trend and data distribution range of the first hydrological monitoring data and water curtain system experimental data are analyzed, and the potential risk areas are predicted based on the data evolution trend and data distribution range;

[0008] Before the cavern is put into operation, based on the air tightness test of the potential risk area, the second hydrological monitoring data before the cavern is put into operation is obtained and analyzed. The second hydrological monitoring data includes the surrounding rock fissure water pressure;

[0009] During the operation of the cavern, monitor the third hydrological monitoring data and water curtain water supply system data of the potential risk area; the third hydrological monitoring data includes natural groundwater level data, hydraulic balance data and groundwater quality data;

[0010] According to the second hydrological monitoring data, the third hydrological monitoring data and the water curtain water supply system data, based on the pre-constructed water seal safety evaluation system, the local dynamic risk levels of different risk indicators in the potential risk area are determined, and the overall risk level of the cavern is determined based on the local dynamic risk levels.

[0011] In some optional embodiments, obtaining the first hydrological monitoring data and the water curtain system experimental data includes:

[0012] Collect the first hydrological monitoring data and water curtain system experimental data;

[0013] The first hydrological monitoring data includes at least one of groundwater level and water quality data, atmospheric pressure and precipitation data, pore water pressure data, seepage points in the cave and seepage point characteristic data, construction water consumption and drainage data;

[0014] The experimental data of the water curtain system includes at least one of the water supply data of the water curtain tunnel and the water curtain hole and the water injection quality data of the water curtain hole;

[0015] The water curtain system test includes at least one of the following: single-hole water pressure test, effectiveness test, and comprehensive hydraulic test.

[0016] In some optional embodiments, based on the airtightness experiment of the potential risk area, the second hydrological monitoring data before the cavern operation is obtained and analyzed, including:

[0017] Conduct airtightness tests on potential risk areas and collect the second hydrological monitoring data during the airtightness test. The second hydrological monitoring data includes groundwater level data and pressure data; the pressure data includes surrounding rock fissure water pressure;

[0018] Analyze groundwater level and pressure data.

[0019] In some optional embodiments, the above method further includes: before performing the airtightness test on the potential risk area, determining whether the following experimental conditions are met, and if so, performing the airtightness test:

[0020] The underground cavern has been completed and passed the acceptance inspection;

[0021] The shaft installation project and equipment commissioning have been completed and passed the acceptance inspection;

[0022] The cavern tanks in the cavern have been calibrated;

[0023] The groundwater level and pressure monitoring system has been installed and commissioned, and data recording has begun.

[0024] In some optional embodiments, the air tightness test includes a preparation stage, a gas injection and pressure increase stage, a pressure stabilization stage, and a detection and determination stage:

[0025] During the preparation stage, water is injected into the construction tunnel, water curtain tunnel and shaft, instruments and equipment with measurement range and accuracy technical requirements that meet the needs of air tightness test analysis and judgment are prepared and debugged, and monitoring instruments are started. The monitoring instruments include at least one of the groundwater level, water pressure, initial temperature in the cave tank and liquid level monitoring instruments in the cave tank;

[0026] During the gas injection and pressure-increasing stage, the test gas is injected into the test cavern at the preset gas pressure-increasing rate, and the temperature and pressure of the injected gas are controlled. The monitoring index data of the cavern is measured and recorded at the preset frequency.

[0027] During the pressure stabilization stage, the difference between the gas pressure in the cavern and the preset test pressure is controlled to be no greater than the set pressure threshold. When the difference is greater than the set pressure threshold, the gas pressure in the cavern is adjusted by injecting gas, and the monitoring index data of the cavern is measured and recorded at a preset frequency;

[0028] During the detection and judgment stage, the monitoring index data of the cavern is measured and recorded at a preset frequency. The real-time change data of the test gas pressure in the cavern is determined based on the temperature change data in the cavern, the gas volume change data caused by the liquid level change in the pump pit, and the amount of air dissolved in the fracture water. The real-time change data at different times are compared with the initial pressure data of this stage. If the change is not greater than the preset allowable change, the air tightness of the cavern is determined to be qualified.

[0029] In some optional embodiments, according to the second hydrological monitoring data, the third hydrological monitoring data and the water curtain water supply system data, based on the pre-built water seal safety evaluation system, the local dynamic risk level of different risk indicators in the potential risk area is determined, and the overall risk level of the cavern is determined based on the local dynamic risk level, including:

[0030] Determine the dynamic risk level of surrounding rock fissure water pressure based on the surrounding rock fissure water pressure in the second hydrological monitoring data and the pre-established surrounding rock fissure water pressure evaluation system;

[0031] Determine the dynamic risk level of natural groundwater level based on the natural groundwater level data in the third hydrological monitoring data and the pre-established natural groundwater level evaluation system;

[0032] Determine the hydraulic balance dynamic risk level based on the hydraulic balance data in the third hydrological monitoring data and the pre-established hydraulic balance evaluation system;

[0033] Determine the dynamic risk level of groundwater quality based on the groundwater quality data in the third hydrological monitoring data and the pre-established groundwater quality evaluation system;

[0034] Determine the dynamic risk level of the water curtain water level based on the water curtain water level data in the water curtain water supply system data and the pre-established water curtain water level evaluation system;

[0035] The dynamic risk level of surrounding rock fissure water pressure, the dynamic risk level of natural groundwater level, the dynamic risk level of hydraulic balance, the dynamic risk level of groundwater quality and the dynamic risk level of water curtain water level are weighted and comprehensively processed to obtain the overall risk level of the cavern.

[0036] In some optional embodiments, determining the dynamic risk level of surrounding rock fissure water pressure according to the surrounding rock fissure water pressure in the second hydrological monitoring data and a pre-established surrounding rock fissure water pressure evaluation system includes:

[0037] Obtain the surrounding rock fissure water pressure monitored by the piezometer installed in the pressure gauge hole, determine the water potential change according to the surrounding rock fissure water pressure, analyze the correlation between the slurry diffusion and seepage in the underground water-sealed cavern according to the water potential change, and establish a surrounding rock fissure water pressure evaluation system based on the correlation between the slurry diffusion and seepage in the underground water-sealed cavern;

[0038] Establishing a surrounding rock fissure water pressure evaluation system includes: establishing a magnitude relationship between the surrounding rock fissure water pressure monitored by a piezometer and the pressure in the pressure stabilization stage of an air tightness experiment, and a quantitative ratio of the head loss quantitative index FLF of the surrounding rock fissure water pressure monitored by a piezometer tending to a specified value, and establishing a corresponding relationship between the above magnitude relationship, the above quantitative ratio and the dynamic risk level of the surrounding rock fissure water pressure;

[0039] FLF=(H w -H c ) / (H w -H s ), where FLF is the friction loss coefficient, H w is the water head of the water curtain tunnel, H cH is the head of surrounding rock fissure water pressure converted based on the piezometer reading; s It is the vault water head of the oil storage cavern.

[0040] In some optional embodiments, determining the natural groundwater level dynamic risk level according to the natural groundwater level data in the third hydrological monitoring data and a pre-established natural groundwater level evaluation system includes:

[0041] Obtain the natural groundwater level data monitored by the piezometer installed in the pressure gauge hole, and establish a natural groundwater level evaluation system based on the natural groundwater level data;

[0042] Establishing a natural groundwater level evaluation system includes: establishing a first high-low relationship between the natural groundwater level monitored by the piezometer and the designed groundwater level, and establishing a corresponding relationship between the first high-low relationship, the leakage signs of surrounding oil and gas, and the dynamic risk level of the natural groundwater level;

[0043] The natural groundwater level conforms to the following formula: H l =P c ×100+H0≥H d , where H l is the natural groundwater level, which is the head value converted based on the piezometer reading, P c Osmometer reading, H0—Osmometer installation height, H d Design groundwater level.

[0044] In some optional embodiments, the hydraulic balance dynamic risk level is determined according to the hydraulic balance data in the third hydrological monitoring data and a pre-established hydraulic balance evaluation system, including:

[0045] Obtain the cavern drainage, water inflow and water replenishment of the water curtain system, use the cavern drainage and water replenishment of the water curtain system as hydraulic balance data, evaluate the hydraulic balance of the cavern based on the hydraulic balance data and establish a hydraulic balance evaluation system;

[0046] The establishment of a hydraulic balance evaluation system includes: establishing the correspondence between the drainage volume of the cavern, the excess ratio of the water replenishment volume of the water curtain system, and the excess ratio of the water inflow volume of the cavern and the dynamic risk level of the hydraulic balance.

[0047] In some optional embodiments, determining the groundwater quality dynamic risk level according to the groundwater quality data in the third hydrological monitoring data and a pre-established groundwater quality evaluation system includes:

[0048] Obtain groundwater quality data and establish a groundwater quality evaluation system based on the groundwater quality data;

[0049] Establishing a groundwater quality evaluation system includes: obtaining the degree of proximity between the physical, chemical, and bacterial indicators of groundwater quality and the corresponding indicators in the water quality monitoring report before the cavern operation, and establishing a corresponding relationship between the above-mentioned degree of proximity, changes in the color and odor of the water body, and the dynamic risk level of groundwater quality.

[0050] In some optional embodiments, the dynamic risk level of the water curtain water level is determined according to the water curtain water level data in the water curtain water supply system data and a pre-established water curtain water level evaluation system, including:

[0051] Obtain the water curtain water level data monitored by the piezometer installed in the pressure gauge hole, and establish a water curtain water level evaluation system based on the water curtain water level data;

[0052] Establishing a water curtain water level evaluation system includes: establishing a second high-low relationship between the water curtain water level height monitored by the piezometer and the designed water curtain water level height, and establishing a corresponding relationship between the second high-low relationship, changes in surrounding rock fissure water pressure, signs of surrounding oil and gas leakage and the dynamic risk level of the water curtain water level.

[0053] In a second aspect, an embodiment of the present invention provides a device for evaluating the safety of underground water seal caverns during their entire life cycle, comprising:

[0054] The data acquisition module is used to obtain hydrological monitoring information of underground water-sealed caverns and experimental data of water curtain systems during the construction period; to obtain and analyze hydrological information of underground water-sealed caverns and surrounding rock fissure water pressure before operation; and to obtain geological data of the entire life cycle of underground water-sealed caverns during operation;

[0055] The water seal safety evaluation module is used to analyze the evolution trend and distribution range of historical data based on hydrological monitoring information and water curtain system experimental data, and predict future potential risk areas based on the evolution trend of historical data; establish a risk identification and evaluation system for surrounding rock fissure water pressure; determine the water seal safety evaluation system based on the real-time monitoring geological data obtained by the data acquisition module and divide the dynamic risk level of the underground water seal cavern throughout its life cycle.

[0056] An embodiment of the present invention provides a computer storage medium, in which computer executable instructions are stored. When the computer executable instructions are executed by a processor, a method for evaluating the safety of water seals in underground water seal caverns throughout their life cycle is implemented.

[0057] An embodiment of the present invention provides a computer device, including: a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, a method for evaluating the water seal safety of an underground water seal cavern over its entire life cycle is implemented.

[0058] The beneficial effects of the above technical solution provided by the embodiment of the present invention include at least:

[0059] During the construction of the cavern, the first hydrological monitoring data and the water curtain system experimental data are monitored to predict potential risk areas. Before the operation of the cavern, based on the airtightness experiment on the potential risk area, the second hydrological monitoring data before the operation of the cavern is obtained. During the operation of the cavern, the third hydrological monitoring data and the water curtain water supply system data of the potential risk area are monitored. According to the data monitoring and analysis of the entire life cycle of the cavern construction, before operation and during operation, the risk level of the cavern is evaluated based on the pre-constructed water seal safety evaluation system. The above method uses a variety of technologies such as hydrological monitoring and evaluation, water curtain system test, air tightness test, cavern operation and maintenance, etc., deeply explores and utilizes the correlation between monitoring data in different life cycles, and is based on the water seal safety monitoring system of underground water-sealed caverns throughout the entire construction period and operation period. It effectively integrates various monitoring data, including natural groundwater level, water curtain water level, surrounding rock fissure water pressure data, hydraulic balance data, groundwater quality data and other monitoring data, identifies, divides and evaluates the risk level of the cavern, identifies the risk of the water seal cavern in time, obtains accurate and reliable evaluation results, and ensures the long-term, stable and safe operation of the underground water seal cavern. The above method has the advantages of full life cycle, strong pertinence, high reliability, convenient operation, low cost and wide application range. It solves the discontinuity and limitation problems of the water seal monitoring means used in the built caverns, and can appropriately adjust the parameter settings in the constructed water seal safety evaluation system according to the actual working conditions to achieve fine-tuning of the risk level. The proposed method has important application value for various underground projects and underground space projects such as underground water seal caverns.

[0060] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description, claims, and drawings.

[0061] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0063] Figure 1 Flow chart of a method for evaluating water seal safety of an underground water seal cavern in an embodiment of the present invention;

[0064] Figure 2 A statistical diagram of groundwater level data changes in an embodiment of the present invention;

[0065] Figure 3 is a graph showing changes in pore water pressure in an embodiment of the present invention;

[0066] Figure 4 A statistical diagram of water inflow in an embodiment of the present invention;

[0067] Figure 5 This is an example diagram of a structure schematic diagram for monitoring surrounding rock fissure water pressure in an embodiment of the present invention;

[0068] Figure 6 This is an example diagram of blockage around the water curtain system in an embodiment of the present invention;

[0069] Figure 7 This is an example diagram of a blockage around a cave chamber according to an embodiment of the present invention;

[0070] Figure 8 It is a structural diagram of a water seal safety evaluation device for an underground water seal cavern throughout its life cycle in an embodiment of the present invention. DETAILED DESCRIPTION

[0071] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0072] The water seal characteristics of underground oil reservoirs determine the complexity and difficulty of their monitoring technology. The inventors of the present application have found that currently, single data monitoring technology is usually used to monitor the water seal safety of underground water seal caverns. The monitoring data is not deeply mined and utilized, and the correlation between the data is not considered during the analysis. A safety monitoring and evaluation system with interrelated data has not been formed, resulting in poor accuracy of the monitoring results of the water seal safety of underground water seal caverns, failure to timely identify the risks of water seal caverns, and inability to effectively conduct risk assessment and safety control.

[0073] In order to solve the problem of underground water-sealed cavern water seal safety evaluation system that has not formed interrelated data in the prior art, an embodiment of the present invention provides a full life cycle safety evaluation method for underground water-sealed caverns, which can timely identify and control risk sources. The method has the advantages of full life cycle, strong pertinence, high reliability, convenient operation, low cost, and wide application range, and is of great significance to ensuring the safe construction and operation of underground rock cavern storage.

[0074] Example

[0075] The embodiment of the present invention provides a method for evaluating the water seal safety of an underground water seal cavern, the process of which is as follows: Figure 1 As shown, the following steps are included:

[0076] Step S101: During the cavern construction, first hydrological monitoring data and water curtain system experimental data are obtained, data evolution trends and data distribution ranges of the first hydrological monitoring data and water curtain system experimental data are analyzed, and potential risk areas are predicted based on the data evolution trends and data distribution ranges.

[0077] Step S102: Before the cavern is put into operation, based on the air tightness experiment of the potential risk area, the second hydrological monitoring data before the cavern is put into operation is obtained and analyzed, and the second hydrological monitoring data includes the surrounding rock fissure water pressure.

[0078] Step S103: During the operation of the cavern, the third hydrological monitoring data and the water curtain water supply system data of the potential risk area are monitored; the third hydrological monitoring data includes natural groundwater level data, hydraulic balance data and groundwater quality data.

[0079] Step S104: According to the second hydrological monitoring data, the third hydrological monitoring data and the water curtain water supply system data, based on the pre-constructed water seal safety evaluation system, determine the local dynamic risk level of different risk indicators in the potential risk area, and determine the overall risk level of the cavern based on the local dynamic risk level.

[0080] Preferably, in the above step S101, obtaining the first hydrological monitoring data and the water curtain system experimental data includes:

[0081] Collect the first hydrological monitoring data and water curtain system experimental data;

[0082] The first hydrological monitoring data includes at least one of groundwater level and water quality data, atmospheric pressure and precipitation data, pore water pressure data, seepage points in the cave and seepage point characteristic data, construction water consumption and drainage data;

[0083] The experimental data of the water curtain system includes at least one of the water supply data of the water curtain tunnel and the water curtain hole and the water injection quality data of the water curtain hole;

[0084] The water curtain system test includes at least one of the following: single-hole water pressure test, effectiveness test, and comprehensive hydraulic test.

[0085] This embodiment takes a project in the experimental reservoir area as an example to conduct real-time data monitoring of the entire life cycle of the underground water-sealed cavern. The first hydrological monitoring data during the construction period includes:

[0086] 1) Groundwater level and water quality

[0087] The monitoring network in the well-preserved existing exploration boreholes is used to monitor the groundwater level and water quality. Before construction, the location, bottom elevation, and completeness of each borehole must be reviewed to ensure that the data conversion can be achieved. If some boreholes are damaged, additional holes should be drilled nearby, and data conversion and borehole protection work should be carried out.

[0088] 2) Atmospheric pressure and precipitation

[0089] Measure local atmospheric pressure and precipitation, and conduct actual measurements on site in accordance with the specifications of the meteorological department.

[0090] 3) Pore water pressure

[0091] An underground pressure gauge hole is set in the water curtain borehole of the water curtain tunnel, and the pore water pressure is measured by the measuring instrument in the underground pressure gauge hole. The underground pressure gauge hole is divided into three types of boreholes: inclined, horizontal and vertical. 50 underground pressure gauge holes are initially arranged, among which: No. 1 to 30 are horizontal underground pressure gauge holes drilled from the water curtain tunnel, and the hole inclination angle is 2% downward; No. 31 to 40 are vertical underground pressure gauge holes drilled from the water curtain tunnel, and the hole bottom elevation is 10m below the bottom plate of the oil storage cavern; No. 41 to 50 are inclined underground pressure gauge holes drilled from the water curtain tunnel, and the inclination angle of the pressure gauge hole to the vertical plane is 30°, and the hole bottom elevation is 10m below the bottom plate of the oil storage cavern. The number of underground pressure gauge holes, the hole bottom elevation and the hole inclination angle can be appropriately adjusted according to the actual construction situation.

[0092] 4) Water seepage points and characteristic description data in the cave

[0093] Measure and record the amount of water seepage during and after the excavation of each oil storage cavern, connecting tunnel, shaft, construction tunnel and water curtain tunnel. Measure the corresponding mileage, water seepage amount and other information of each water seepage point every day, and complete the characteristic description data of the water seepage point in the underground cavern, such as monitoring the flow rate, source, conductivity, smell, color, etc. of the water seepage point.

[0094] 5) Construction water consumption and drainage volume

[0095] Measure and record the construction water consumption and drainage volume supplied from outside to each main unit of the underground project during the construction process.

[0096] The experimental data of the water curtain system in the embodiment of the present invention include:

[0097] 1) Water supply of water curtain tunnel and water curtain hole

[0098] During the construction process, the water supply from the outside to each water curtain tunnel and the water supply to the water curtain holes in the water curtain tunnel are separately measured and recorded. During the water curtain hole filling process, the water injection flow and injection pressure of each water curtain hole are measured and recorded.

[0099] 2) Water injection quality of water curtain holes

[0100] Water quality sampling and analysis of the water curtain supply pipeline is carried out regularly to evaluate the physical, chemical and bacterial characteristics of the water supply.

[0101] After collecting the first hydrological monitoring data and water curtain system experimental data, we focus on analyzing areas where the first hydrological monitoring data is abnormal or where regional precipitation funnels appear, and predict potential risk areas based on the data evolution trend and distribution range. Figure 2 This is the groundwater level data change diagram. Figure 2 The horizontal axis represents the date, the vertical axis represents the water level, and the curve in the figure represents the change of water level in each underground pressure gauge hole. Figure 2 As shown, the groundwater level is lower than the allowable water level during the construction period for a long time. The area within 200m of the borehole is a potential risk area. The allowable water level during the construction period is shown in Figure 2 As shown by the horizontal line at the middle water level elevation of 10m, this potential risk area should be marked and should be monitored and evaluated during the operation period. Figure 3 is the pore water pressure variation diagram, Figure 3 The horizontal axis in the middle represents the number of the water curtain hole, and the vertical axis represents the pore water pressure. The pore water pressure is monitored in three stages. The dark five-pointed star water curtain hole with a range of 200m below the theoretical value of pore water pressure in the effectiveness test is a risk area. This area should be marked and should be monitored and evaluated during the operation period. The dark five-pointed star refers to Figure 3 In the position of WC1-HB-6, WC1-HB-7, WC1-HB-18, WC1-HB-19, WC1-HB-23, WC1-HB-24, WC1-HB-39, WC1-HB-40, WC1-HB-47, WC1-HB-48, Figure 3 There are two straight lines in the figure. The upper straight line is the theoretical value of pore water pressure in stage 1, and the lower straight line is the theoretical value of pore water pressure in stage 2 / 3.

[0102] In the early stage of operation, the water inflow of each oil storage cavern should be measured separately. For the statistical chart of water inflow, please refer to Figure 4 As shown, Figure 4 The water inflow of several caverns over several days is recorded in the data. If the water inflow exceeds the standard, the oil storage cavern should be marked and should be monitored and evaluated during the operation period.

[0103] Preferably, in the above step S102, based on the air tightness experiment of the potential risk area, the second hydrological monitoring data before the cavern operation is obtained and analyzed, including:

[0104] Conduct airtightness tests on potential risk areas and collect the second hydrological monitoring data during the airtightness test. The second hydrological monitoring data includes groundwater level data and pressure data; the pressure data includes surrounding rock fissure water pressure;

[0105] Analyze groundwater level and pressure data.

[0106] Preferably, before conducting an airtightness test on a potential risk area, determine whether the following experimental conditions are met. If so, conduct an airtightness test:

[0107] The underground cavern has been completed and passed the acceptance inspection;

[0108] The shaft installation project and equipment commissioning have been completed and passed the acceptance inspection;

[0109] The cavern tanks in the caverns have been calibrated; the pump pits in the cavern tanks must also be calibrated;

[0110] The groundwater level and pressure monitoring system has been installed and commissioned, and data recording has begun.

[0111] The various hydrological monitoring data during the air tightness test are an important basis for the subsequent water seal safety evaluation, especially the monitoring data such as the fissure water pressure during the pressure stabilization stage. If the pressure change after correction during the air tightness test is not greater than the design allowable value, the cavern can be judged to be airtight. However, if the surrounding rock fissure water pressure value monitored by some pressure gauge holes is lower than the theoretical value calculated by the seepage field, the area should be marked as a leakage risk area during the operation period.

[0112] The airtightness test is carried out in different tanks, and can be carried out on multiple tanks or all tanks at the same time. The medium of the airtightness test is air or inert gas. The airtightness test pressure is 1.05 times the maximum tank design pressure.

[0113] Preferably, the air tightness test includes a preparation stage, a gas injection and pressure increase stage, a pressure stabilization stage and a detection and determination stage.

[0114] Preferably, during the preparation stage, water is injected into the construction tunnels, water curtain tunnels and shafts, instruments and equipment whose measuring range and accuracy technical requirements meet the needs of air tightness test analysis and judgment are prepared and debugged, and monitoring instruments are started, including at least one of the monitoring instruments for groundwater level, water pressure, initial temperature in the cavern and liquid level in the cavern.

[0115] In this embodiment, during the preparation stage, when water is injected into the construction tunnel, water curtain tunnel and vertical shaft, if water injection and cavern pressure testing are carried out simultaneously, the cavern top water level should be maintained at 102P+25m, where P is the cavern pressure in MPa. After water injection is completed, the water level should reach or exceed the designed groundwater level elevation during operation.

[0116] Preferably, during the gas injection and pressurization stage, the test gas is injected into the test cave tank at a preset gas pressurization rate, and the temperature and pressure of the injected gas are controlled, and the monitoring index data of the cave tank is measured and recorded at a preset frequency.

[0117] In this embodiment, during the gas injection and pressure-raising stage, the pressure-raising rate of gas injected into the test cavern should not exceed 30 kPa / d, and the temperature of the test gas injected into the cavern should be 2 to 3 °C lower than the stable temperature of the cavern during operation. When the test gas pressure in the cavern reaches the test pressure, the injection should be stopped immediately. The items and frequency of measurement and recording during the gas injection and pressure-raising stage should comply with the provisions of Table 1.

[0118] Table 1

[0119] Serial number Measurement record items Measurement recording frequency 1 Gas pressure in the tank Record once every 2 hours 2 Atmospheric pressure Record once every 2 hours 3 Compressed air injection temperature Record once every 2 hours 4 Test hole tank temperature Record once every 2 hours 5 Test the liquid level in the cave tank Record once every 2 hours 6 Test the liquid level in the pit tank pump Record once every 2 hours 7 Water level above shaft sealing plug Record 2 times a day 8 Groundwater monitoring hole water level Record 2 times a day 9 Surrounding rock fracture water pressure Record 4 times a day

[0120] Preferably, during the pressure stabilization stage, the difference between the gas pressure in the cavern and the preset test pressure is controlled to be no greater than a set pressure threshold. When the difference is greater than the set pressure threshold, the gas pressure in the cavern is adjusted by injecting gas, and the monitoring index data of the cavern is measured and recorded at a preset frequency.

[0121] After the gas injection and pressure-raising stage, the pressure-stabilizing stage begins. In this embodiment, when the temperature change of the gas in the cavern does not exceed ±0.1°C / d, the cavern temperature is considered to be stable; during the test gas pressure-stabilizing process in the cavern, the cavern gas pressure should be ensured to be the same as the test pressure value, and an appropriate amount of gas can be injected when the cavern gas pressure decreases. The surrounding rock fissure water pressure value during the air tightness test pressure-stabilizing stage is an important basic parameter for monitoring the surrounding rock fissure water pressure during the operation of the cavern, and it should be recorded in detail, carefully, and archived. The items and frequency of measurement records during the pressure-stabilizing stage should comply with the provisions of Table 2.

[0122] Table 2

[0123] Serial number Measurement record items Measurement recording frequency 1 Gas pressure in the tank Record once every hour 2 Atmospheric pressure Record once every hour 3 Volume of fissure water discharged from cavernous tank Real-time recording 4 Test hole tank temperature Record once every hour 5 Test the liquid level in the cave tank Record once every hour 6 Test the liquid level in the pit tank pump Record once every hour 7 Water level above shaft sealing plug Record 2 times a day 8 Water level at surface hydrological monitoring hole Record 2 times a day 9 Surrounding rock fracture water pressure Record 4 times a day

[0124] Preferably, during the detection and determination stage, the monitoring index data of the cavern are measured and recorded at a preset frequency, and the real-time change data of the test gas pressure in the cavern is determined based on the temperature change data in the cavern, the gas volume change data caused by the liquid level change in the pump pit, and the amount of air dissolved in the fissure water; the real-time change data at different times are compared with the initial pressure data of this stage. If the change is not greater than the preset allowable change, the air tightness of the cavern is determined to be qualified.

[0125] After the pressure stabilization stage, the detection and determination stage begins. In this embodiment, the duration of the detection and determination stage is not less than 100 hours. The items and frequency requirements of the measurement records in the detection and determination stage must comply with the provisions of Table 1 or Table 2. In this stage, the measured and recorded test gas pressure value in the cavern should be corrected according to the temperature change value in the cavern, the gas volume change value caused by the liquid level change in the pump pit, and the amount of air dissolved in the fissure water; when the corrected pressure value is compared with the initial pressure value of this stage and the change is not greater than the design allowable value, the air tightness of the cavern can be judged to be qualified.

[0126] The changes in gas pressure caused by temperature changes in the cave tank and liquid level changes in the pump pit can be calculated according to the ideal gas state equation.

[0127] When calculating the effect of gas dissolving into the water cushion on the gas pressure in the cavern, use Table 3 to calculate the amount of air dissolved in the water.

[0128] Table 3

[0129]

[0130] Preferably, in the above step S103, during the operation of the cavern, the third hydrological monitoring data and the water curtain water supply system data of the potential risk area are monitored; the third hydrological monitoring data includes natural groundwater level data, hydraulic balance data and groundwater quality data, including:

[0131] Monitor natural groundwater level data, including surface hydrological monitoring hole water level and vertical shaft water level; surface hydrological monitoring hole water level is monitored by placing piezometers in the hole, and vertical shaft water level is monitored by placing piezometers in the vertical shaft;

[0132] Monitor hydraulic balance data, evaluate the hydraulic balance of the reservoir area by measuring the drainage volume of the cavern and the water replenishment volume of the water curtain system; monitor the water replenishment and drainage volume of the cavern through flow meters installed in the water replenishment system of the underground water-sealed cavern construction tunnel and monitoring well, and the drainage system of the oil shaft;

[0133] Monitor groundwater quality data, obtain groundwater in the reservoir area and conduct groundwater quality analysis. Groundwater quality analysis is divided into physical analysis, chemical analysis and bacterial analysis to obtain groundwater quality data;

[0134] Monitor the water curtain water supply system data, which includes the water curtain water level data. The water curtain water level is monitored by placing a piezometer in the monitoring well.

[0135] Preferably, in the above step S104, according to the second hydrological monitoring data, the third hydrological monitoring data and the water curtain water supply system data, based on the pre-constructed water seal safety evaluation system, the local dynamic risk level of different risk indicators in the potential risk area is determined, and the overall risk level of the cavern is determined based on the local dynamic risk level, including:

[0136] Determine the dynamic risk level of surrounding rock fissure water pressure based on the surrounding rock fissure water pressure in the second hydrological monitoring data and the pre-established surrounding rock fissure water pressure evaluation system;

[0137] Determine the dynamic risk level of natural groundwater level based on the natural groundwater level data in the third hydrological monitoring data and the pre-established natural groundwater level evaluation system;

[0138] Determine the hydraulic balance dynamic risk level based on the hydraulic balance data in the third hydrological monitoring data and the pre-established hydraulic balance evaluation system;

[0139] Determine the dynamic risk level of groundwater quality based on the groundwater quality data in the third hydrological monitoring data and the pre-established groundwater quality evaluation system;

[0140] Determine the dynamic risk level of the water curtain water level based on the water curtain water level data in the water curtain water supply system data and the pre-established water curtain water level evaluation system;

[0141] The dynamic risk level of surrounding rock fissure water pressure, the dynamic risk level of natural groundwater level, the dynamic risk level of hydraulic balance, the dynamic risk level of groundwater quality and the dynamic risk level of water curtain water level are weighted and comprehensively processed to obtain the overall risk level of the cavern.

[0142] Preferably, the surrounding rock fissure water pressure dynamic risk level is determined according to the surrounding rock fissure water pressure in the second hydrological monitoring data and a pre-established surrounding rock fissure water pressure evaluation system, including:

[0143] Obtain the surrounding rock fissure water pressure monitored by the piezometer placed in the pressure gauge hole, determine the water potential change according to the surrounding rock fissure water pressure, analyze the correlation between the slurry diffusion and seepage of the underground water-sealed cavern according to the water potential change, and establish a surrounding rock fissure water pressure evaluation system according to the correlation between the slurry diffusion and seepage of the underground water-sealed cavern;

[0144] Establishing a surrounding rock fissure water pressure evaluation system includes: establishing a magnitude relationship between the surrounding rock fissure water pressure monitored by a piezometer and the pressure in the pressure stabilization stage of an air tightness experiment, and a quantitative ratio of the head loss quantitative index FLF of the surrounding rock fissure water pressure monitored by a piezometer tending to a specified value, and establishing a corresponding relationship between the above magnitude relationship, the above quantitative ratio and the dynamic risk level of the surrounding rock fissure water pressure;

[0145] FLF=(H w -H c ) / (H w -H s ), where FLF is the friction loss coefficient, H w is the water head of the water curtain tunnel, H c is the water head of surrounding rock fissure pressure converted based on the piezometer reading; Hs is the vault water head of the oil storage cavern.

[0146] The water pressure around the cavern affects the seepage field of the entire reservoir area. In this embodiment, a piezometer is placed in the pressure gauge hole before operation to monitor the water pressure in the surrounding rock fissures. By calculating the change in water potential, a semi-quantitative analysis of the correlation between slurry diffusion and seepage in the underground water-sealed cavern is performed. Figure 5This is a structural example diagram for monitoring the water pressure in the surrounding rock fissures. The arch shape in the figure is the cavern of the cavern. The piezometer is placed in the pressure gauge hole. The other parameters are in Figure 5 Winning bid.

[0147] If there is a blockage around the water curtain system, the water curtain system will not be able to supplement the surrounding rock cracks. The water pressure in the surrounding rock cracks between the water curtain system and the cavern will first drop sharply and then remain stable. c Approaching Hs, FLF tends to 1. Figure 6 This is an example of blockage around the water curtain system. w is the water head of the water curtain tunnel, H w The nearby shaded area is the area blocked around the water curtain system.

[0148] If there is a blockage around the cavern of the cavern, the fissure water supply around the cavern is insufficient, and the surrounding rock fissure water pressure between the water curtain system and the oil storage cavern is first stable and then begins to drop sharply near the oil storage cavern. c Approaching Hw, FLF tends to 0. Figure 7 This is an example of a blockage around a cavern. The shaded area around the cavern is the blocked area around the cavern.

[0149] During operation, when the piezometer reading in the pressure gauge hole is less than the surrounding rock fissure water pressure during the pressure stabilization stage of the air tightness experiment, the dynamic risk level of the surrounding rock fissure water pressure is marked.

[0150] Preferably, the natural groundwater level dynamic risk level is determined based on the natural groundwater level data in the third hydrological monitoring data and a pre-established natural groundwater level evaluation system, including:

[0151] Obtain the natural groundwater level data monitored by the piezometer installed in the pressure gauge hole, and establish a natural groundwater level evaluation system based on the natural groundwater level data;

[0152] Establishing a natural groundwater level evaluation system includes: establishing a first high-low relationship between the natural groundwater level monitored by the piezometer and the designed groundwater level, and establishing a corresponding relationship between the first high-low relationship, the leakage signs of surrounding oil and gas, and the dynamic risk level of the natural groundwater level;

[0153] The natural groundwater level conforms to the following formula: H l =P c ×100+H0≥H d , where H l is the natural groundwater level, which is the head value converted based on the piezometer reading, P c Osmometer reading, H0—Osmometer installation height, H d Design groundwater level.

[0154] The natural groundwater level includes the water level of the surface hydrological monitoring hole and the water level of the vertical shaft. The natural groundwater level in the reservoir area is affected by factors such as rainfall, atmospheric pressure, water potential, and reservoir boundary conditions. Surface hydrological monitoring is intended to check the hydrogeological environment required for the sealing of cavern storage products. If the overall water environment moves, it may affect the basis of the water seal design.

[0155] The water level of the surface hydrological monitoring hole is automatically monitored by placing a piezometer in the hole, and the water level of the vertical shaft is automatically monitored by placing a piezometer in the vertical shaft. In this embodiment, the piezometer is placed 10m-20m above the vertical shaft sealing plug, and the measurement accuracy is ±0.1%. The water level in the surface hydrological monitoring hole and the vertical shaft meet the following requirements: H l =P c ×100+H0≥H d The installation height and measurement accuracy of the piezometer can be adjusted according to actual conditions.

[0156] During operation, when the water level in a hydrogeological monitoring hole or a vertical shaft is lower than the designed groundwater level, check for signs of oil and gas leakage in the surrounding area and mark the dynamic risk level of the natural groundwater level.

[0157] Preferably, the hydraulic balance dynamic risk level is determined based on the hydraulic balance data in the third hydrological monitoring data and a pre-established hydraulic balance evaluation system, including:

[0158] Obtain the cavern drainage, water inflow and water replenishment of the water curtain system, use the cavern drainage and water replenishment of the water curtain system as hydraulic balance data, evaluate the hydraulic balance of the cavern based on the hydraulic balance data and establish a hydraulic balance evaluation system;

[0159] The establishment of a hydraulic balance evaluation system includes: establishing the correspondence between the drainage volume of the cavern, the excess ratio of the water replenishment volume of the water curtain system, and the excess ratio of the water inflow volume of the cavern and the dynamic risk level of the hydraulic balance.

[0160] In this embodiment, automatic monitoring of hydraulic balance is set during operation to monitor the hydraulic exchange between the cavern and the surrounding rock, measure the drainage volume of the cavern and the water replenishment volume of the water curtain system, and evaluate the hydraulic balance status of the reservoir area.

[0161] Underground water-sealed cavern projects usually have flow meters installed in the water replenishment systems of construction tunnels and monitoring wells, and the drainage systems of oil outlet shafts. Groundwater is replenished into the water curtain tunnels through the water replenishment systems of the construction tunnels and monitoring wells, and the water gushing into the caverns is pumped out through the drainage system of the oil outlet shaft to maintain the daily operation of the cavern.

[0162] The hydraulic balance of the cavern is evaluated by regularly collecting the water replenishment and water inflow data of the water curtain system. Based on the collected water replenishment and water inflow data, combined with the local annual average rainfall information, the annual average hydraulic fluctuation of the cavern is determined, providing a basis for the daily maintenance of the cavern.

[0163] In this embodiment, the total amount of water replenishment of the construction tunnel replenishment system and the total amount of drainage of the oil shaft are monitored once a day. Close attention should be paid to the load of the drainage equipment. When the drainage equipment cannot guarantee the timely discharge of the gushing water, it should be replaced with a pump with a larger drainage capacity or an additional pump should be installed, and the dynamic risk level of the hydraulic balance should be marked.

[0164] Preferably, the groundwater quality dynamic risk level is determined based on the groundwater quality data in the third hydrological monitoring data and a pre-established groundwater quality evaluation system, including:

[0165] Obtain groundwater quality data and establish a groundwater quality evaluation system based on the groundwater quality data;

[0166] Establishing a groundwater quality evaluation system includes: obtaining the degree of proximity between the physical, chemical, and bacterial indicators of groundwater quality and the corresponding indicators in the water quality monitoring report before the cavern operation, and establishing a corresponding relationship between the above-mentioned degree of proximity, changes in the color and odor of the water body, and the dynamic risk level of groundwater quality.

[0167] During the operation period, the groundwater quality in the reservoir area is regularly monitored. The groundwater quality analysis includes physical, chemical and bacterial analysis. By analyzing the water quality, the impact of the storage products on the surrounding rock and groundwater is checked, and the groundwater resource environment is protected in accordance with environmental protection requirements. Water quality monitoring is aimed at ensuring that the groundwater quality of the entire reservoir area meets the requirements of being similar to and compatible with the original water quality in the reservoir area. The parameters of water quality monitoring are also used for hydrogeological analysis and corrosiveness evaluation.

[0168] The water quality monitoring of underground water-sealed caverns is different from that of sewage treatment. The evaluation is based on the undisturbed natural water quality before construction, and mainly analyzes the unstable factors that affect the stability of the caverns and the water seal environment.

[0169] In this embodiment, physical indicators affecting cavern stability and water seal environment are determined through physical analysis of groundwater quality, such as:

[0170] (1) Analyze the conductivity and water temperature of groundwater, which are physical indicators that can reflect the characteristics of groundwater;

[0171] (2) Analyze the suspended matter in groundwater. This physical indicator can reveal the amount of suspended particles in groundwater, such as mud, sand, and dust. If the suspended matter exceeds the standard, it will cause the blockage of surrounding rock cracks and destroy the water seal environment.

[0172] In addition to the above physical indicators, other physical indicators can also be analyzed.

[0173] Through chemical analysis of groundwater quality, chemical indicators that affect cavern stability and water seal environment are determined, such as:

[0174] (1) Analyze whether the anions and cations in groundwater are balanced. Anion-cation balance analysis is used to evaluate water quality and test quality. If anions and cations are unbalanced, the water quality test items should be reviewed, which may be due to large measurement errors of certain ions;

[0175] (2) Analyze COD. COD is the chemical oxygen demand, which can reflect the degree of groundwater pollution by reducing substances. This index is an important indicator for judging organic pollution in water bodies;

[0176] (3) Analyze the pH value. The pH value represents the negative logarithm of the hydrogen ion activity in water. Chemical changes in the groundwater environment and production processes will cause changes in the pH value.

[0177] In addition to the above chemical indicators, other chemical indicators can also be analyzed.

[0178] Through bacterial analysis of groundwater quality, bacterial indicators that affect cavern stability and water seal environment are determined, such as:

[0179] (1) Analyze the total amount of aerobic and anaerobic bacteria, which can corrode steel structures and pollute the groundwater environment;

[0180] (2) Analyze the content of sulfate-reducing bacteria. In the absence of oxygen or with very little oxygen, sulfate-reducing bacteria reduce sulfate to hydrogen sulfide, which corrodes steel structures;

[0181] (3) Analyze the content of slime-forming bacteria. Slime-forming bacteria grow and reproduce the fastest and are prone to synthesizing capsules and slime layers on the surface of cracks, blocking joints and cracks and destroying the water seal environment.

[0182] In addition to the above bacterial indicators, other bacterial indicators can also be analyzed.

[0183] The water quality analysis recommended in this embodiment includes physical analysis, chemical analysis and bacterial analysis. In addition, it also includes dissolved gas molecules to determine dissolved gas indicators that affect cavern stability and water seal environment, such as:

[0184] (1) Analyze the volume of dissolved gas. By analyzing the volume and relative content of dissolved gas in groundwater, review the water seal environment of the cavern to determine whether there is a possibility of leakage of stored products, and determine the degree of groundwater contamination and the duration of water contamination;

[0185] (2) Analyze the CO2 and O2 content in groundwater. The growth and death of bacteria and aquatic organisms in water will cause changes in the CO2 and O2 content in water. If the free CO2 content in water exceeds the equilibrium amount, it will react with CaCO3 in the rock to erode the rock and destroy the stability of the surrounding rock.

[0186] (3) Analyze the H2S content in groundwater. H2S in water is mainly produced by the action of reducing bacteria. When the water contains abundant sulfate and organic matter, the reducing bacteria can reduce sulfate and decompose organic protein to produce a large amount of hydrogen sulfide. This is more likely to occur when the water is lacking oxygen, thus polluting the groundwater environment.

[0187] In addition to the above dissolved gas indicators, other dissolved gas indicators can also be analyzed.

[0188] In this embodiment, the monitoring and evaluation of groundwater quality in the reservoir area should refer to the water quality test report before construction or in the initial stage of operation, analyze the relative content ratio of various indicators, and meet the local groundwater standards and environmental protection requirements, for example:

[0189] Among the physical indicators, the total amount of suspended matter is less than 10 mg / L;

[0190] Among the chemical indicators, the hydrocarbon content is less than 10ppm; the pH is between 6.5 and 8.5;

[0191] Among the bacterial indicators, the total amount of aerobic bacteria is less than 1000 / ml; the total amount of anaerobic bacteria is less than 1000 / ml; the content of sulfate-reducing bacteria is 0 / ml; and the content of mucus-forming bacteria is 0 / ml.

[0192] If the groundwater quality analysis does not meet the requirements, the dynamic risk level of the groundwater quality involved in the specific indicators needs to be marked.

[0193] Preferably, the dynamic risk level of the water curtain water level is determined according to the water curtain water level data in the water curtain water supply system data and the pre-established water curtain water level evaluation system, including:

[0194] Obtain the water curtain water level data monitored by the piezometer installed in the pressure gauge hole, and establish a water curtain water level evaluation system based on the water curtain water level data;

[0195] Establishing a water curtain water level evaluation system includes: establishing a second high-low relationship between the water curtain water level height monitored by the piezometer and the designed water curtain water level height, and establishing a corresponding relationship between the second high-low relationship, changes in surrounding rock fissure water pressure, signs of surrounding oil and gas leakage and the dynamic risk level of the water curtain water level.

[0196] During the operation, a control system is set up to realize the real-time linkage between the water curtain water supply system and the water level measuring device of the monitoring well, automatically detect the water curtain water level, and automatically control the water replenishment function.

[0197] The water potential in the water curtain tunnel should be kept constant by controlling the water replenishment mechanism in the construction tunnel. The water level in the water curtain tunnel should be automatically monitored by placing a piezometer in the monitoring well. In this embodiment, the piezometer is placed 5m-10m above the top plate of the water curtain tunnel, and the measurement accuracy is ±0.1%. The water level in the water curtain tunnel should meet the formula H=P c ×100+H0≥H d The requirements are met, H is the head value of the water level in the water curtain tunnel converted based on the osmometer reading, and the water level in the water curtain tunnel is used as the water curtain water level. The osmometer installation height and measurement accuracy can be adjusted according to actual conditions.

[0198] The water curtain water supply system and the water level measurement device of the monitoring well have the function of automatically starting and stopping water replenishment, and also provide the function of manual control. In special cases, water replenishment can be manually operated. The device transmits the water level monitoring signal to the integrated control room, which operates the water supply start-up action. The water supply start-up action includes automatic or manual modes, both of which are operated by the integrated control room.

[0199] When the groundwater level in the monitoring well is lower than the designed water curtain level during the operation period, the water curtain water supply system is started to replenish water to the construction tunnel. At the same time, the reservoir area and surrounding groundwater environment should be checked for signs of oil and gas leakage, the cause of the drop in the water curtain tunnel water level should be found, measures should be taken to correct it, and the dynamic risk level of the water curtain water level should be marked.

[0200] Preferably, the dynamic risk level of surrounding rock fissure water pressure, the dynamic risk level of natural groundwater level, the dynamic risk level of hydraulic balance, the dynamic risk level of groundwater quality and the dynamic risk level of water curtain water level are weighted and comprehensively processed to obtain the overall risk level of the cavern.

[0201] Dynamic risk classification and risk warning can be achieved based on the real-time monitored second hydrological monitoring data, third hydrological monitoring data and water curtain water supply system data, providing a direct basis for the safety evaluation and risk decision-making of underground water-sealed caverns.

[0202] The comprehensive safety evaluation table for the entire life cycle of the underground water-sealed cavern water seal is detailed in Table 4. According to the records in Table 4, the dynamic risk level of various data can be timely located and the causes can be analyzed in a targeted manner during the entire life cycle of the cavern operation, and corresponding measures can be taken to correct them in a timely manner to ensure the safe operation of the cavern.

[0203] Table 4

[0204]

[0205]

[0206]

[0207] The table lists the local risks corresponding to each evaluation index. The risk level of the entire underground water-sealed cavern reservoir is divided as follows:

[0208] A total score of 80-100 points means that the entire reservoir area is in a risk-free state;

[0209] A total score of 60-80 points means that the entire reservoir area is in a low-risk state;

[0210] A total score of 40-60 points means that the entire reservoir area is at medium risk;

[0211] A total score of 0-40 points means that the entire reservoir area is in a high-risk state.

[0212] The causes of both local and overall risks should be analyzed in a targeted manner, and measures should be taken to correct them to ensure the safe operation of the cavern.

[0213] The evaluation content, proportion distribution, evaluation criteria and scores, ratings and local risk levels in Table 4 above can be adjusted appropriately according to actual construction conditions.

[0214] In this embodiment, when the osmotic pressure reading in the pressure gauge hole is less than the surrounding rock fissure water pressure in the air tightness test pressure stabilization stage during operation, the dynamic risk level of the surrounding rock fissure water pressure is marked. The measures usually taken for the dynamic risk level are:

[0215] ① Analyze the groundwater quality in the monitoring well to see if there is a large number of bacteria that have blocked the joints and fissures. If so, carry out corresponding sterilization treatment, and analyze the water quality of the water curtain water supply and surface water quality monitoring holes;

[0216] ② Check whether the elevations of surrounding hydrogeological monitoring holes, monitoring wells and other hydrogeological holes are higher than the designed groundwater level and the designed water curtain level.

[0217] When the water level elevation of the surrounding hydrogeological monitoring holes and monitoring wells is higher than the designed groundwater level, the integrity of the water curtain system and the water quality of the water supply should be checked, and the oil and gas leakage detection should be carried out in the piezometer area and the nearby surface. If any problem is found, it should be dealt with immediately, and the groundwater level around the piezometer should be restored at the same time;

[0218] When the water level elevation of the surrounding hydrogeological monitoring holes and monitoring wells is lower than the designed groundwater level and the designed water curtain water level, the water curtain water supply system should be started in time to replenish water and restore the groundwater level to above the designed groundwater level.

[0219] ③ Check whether the water level in the shaft is higher than the designed groundwater level.

[0220] If the water level in the shaft is lower than the designed groundwater level, the shaft sealing plug should be tested for oil and gas leakage. If any problem is found, it should be dealt with immediately. At the same time, artificial water injection should be carried out in the shaft to restore the groundwater level to above the designed groundwater level.

[0221] In this embodiment, during operation, when the water level in a hydrogeological monitoring hole or a vertical shaft is lower than the designed groundwater level, check for signs of oil and gas leakage in the surrounding area and mark the dynamic risk level of the natural groundwater level. The measures usually taken for the dynamic risk level are:

[0222] ① Check whether there are any human activities that damage the hydrogeological environment around the reservoir area, such as drilling wells, construction excavation, etc. If so, the operation supervisor should immediately prohibit such activities and carry out relevant water environment restoration and management work;

[0223] ② Check whether the water level elevations of surrounding hydrogeological monitoring holes and monitoring wells are higher than the designed groundwater level and the designed water curtain water level.

[0224] When the water level elevation of the surrounding hydrogeological monitoring holes and monitoring wells is higher than the designed groundwater level, the integrity of the water curtain system and the water quality of the hole should be checked, and the hole and the nearby surface should be tested for oil and gas leakage. If any problems are found, they should be dealt with immediately, and the groundwater level of the hole and the surrounding area should be restored;

[0225] When the water level elevation of the surrounding hydrogeological monitoring holes is lower than the designed groundwater level, the water curtain water supply system is promptly started to replenish water and restore the groundwater level to above the designed groundwater level.

[0226] ③ Check whether the water level in the shaft is higher than the designed groundwater level.

[0227] If the water level in the surrounding shafts is lower than the designed groundwater level, the shafts and surrounding areas should be inspected for oil and gas leakage. If any problems are found, they should be dealt with immediately. At the same time, artificial water injection should be carried out in the shafts to restore the groundwater level to above the designed groundwater level.

[0228] When special circumstances occur during operation and the designed groundwater level cannot be guaranteed, emergency measures such as opening the water curtain water supply system and temporary water injection should be adopted to restore the water level or reduce the operating pressure in the cave tank.

[0229] In any extreme case, the groundwater level should be ensured not to be lower than the minimum allowable groundwater level during the operation period.

[0230] In this embodiment, if the groundwater quality analysis does not meet the requirements during operation, it is necessary to mark the dynamic risk level of the groundwater quality involved in the specific indicators. For the specific indicators that do not meet the requirements, the measures usually taken are:

[0231] The proliferation of microorganisms in the groundwater environment will cause a sharp drop in oxygen concentration, the death of aquatic organisms, and changes in the CO2 and O2 content in the water. For example, the proliferation of anaerobic microorganisms will cause the groundwater to turn black and smelly through the products produced by anaerobic respiration. In order to prevent the occurrence of hypoxia and black and smelly water bodies caused by the proliferation of bacteria, O2 should be added to the water and organic pollutants should be consumed through the proliferation of bacteria in the water to purify the water.

[0232] If the total amount of suspended matter in the water is greater than 10 mg / l, water filtration measures are required;

[0233] If the bacterial microorganisms in the water exceed the standard, sodium hypochlorite or fungicide should be used for sterilization. Physical, chemical and sterilization methods should be used, such as adding drugs to monitoring wells, to avoid polluting the surrounding groundwater environment. At the same time, local groundwater standards and environmental protection requirements should be followed.

[0234] As for the risks arising from other indicators, we can avoid them according to the implementation of the construction situation to ensure the safe operation of the tunnel, which are not listed here one by one.

[0235] Based on the same inventive concept, the embodiment of the present invention also provides a device for evaluating the safety of underground water seal caverns throughout their life cycle. The device can be arranged in a device having a computer instruction processing function. The structure of the device is as follows: Figure 8 As shown, the package

[0236] The data acquisition module 11 is used to obtain the hydrological monitoring information of the underground water-sealed cavern and the experimental data of the water curtain system during the construction period; to obtain and analyze the hydrological information of the underground water-sealed cavern and the surrounding rock fissure water pressure before operation; and to obtain the geological data of the entire life cycle of the underground water-sealed cavern during operation;

[0237] The water seal safety evaluation module 12 is used to analyze the evolution trend and distribution range of historical data based on the hydrological monitoring information and the experimental data of the water curtain system, and predict the potential risk areas in the future based on the evolution trend of historical data; establish a risk identification and evaluation system for surrounding rock fissure water pressure; determine the water seal safety evaluation system based on the real-time monitoring geological data obtained by the data acquisition module and divide the dynamic risk level of the underground water seal cavern throughout its life cycle.

[0238] Regarding the underground water seal cavern full life cycle water seal safety evaluation device in the above-mentioned embodiment, the specific manner in which each module performs operations has been described in detail in the embodiment of the method and will not be elaborated here.

[0239] The above method and device of this embodiment monitors the first hydrological monitoring data and the water curtain system experimental data to predict the potential risk area during the cavern construction; before the cavern is put into operation, based on the airtightness experiment of the potential risk area, the second hydrological monitoring data before the cavern is put into operation is obtained; during the operation of the cavern, the third hydrological monitoring data and the water curtain water supply system data of the potential risk area are monitored; according to the data monitoring and analysis of the whole life cycle of the cavern construction, before operation and during operation, the risk level of the cavern is evaluated based on the pre-built water seal safety evaluation system. The data monitoring during the construction period is the basis for the data monitoring and evaluation during the operation period, and the data monitoring during the operation period is the continuation of the data monitoring during the construction period of the cavern. The above method effectively integrates various monitoring data during the whole life cycle of the cavern, and uses multiple monitoring data such as natural groundwater level, water curtain water level, surrounding rock fissure water pressure, hydraulic balance, groundwater quality, etc. to create a safety risk identification and evaluation system for underground water seal caverns, deeply mine and utilize various monitoring data, and timely identify the risks of water seal caverns according to the correlation between the data, so as to ensure the long-term, stable and safe operation of underground water seal caverns. The discontinuity and limitation of the water seal monitoring methods used in the existing caverns are solved. At the same time, the parameter settings, evaluation standards and scores can be appropriately adjusted according to the actual working conditions to achieve fine-tuning of the risk level. The proposed method has important application value for various underground projects and underground space projects such as underground water seal caverns.

[0240] An embodiment of the present invention also provides a computer storage medium, in which computer executable instructions are stored. When the computer executable instructions are executed by a processor, a method for evaluating the safety of underground water seal caverns during their entire life cycle can be implemented.

[0241] An embodiment of the present invention also provides a computer device, including: a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, a method for evaluating the water seal safety of an underground water seal cavern over its entire life cycle is implemented.

[0242] Unless otherwise specifically stated, terms such as processing, computing, calculating, determining, displaying, etc. may refer to the actions and / or processes of one or more processing or computing systems, or similar devices, which operate and convert data represented as physical (e.g., electronic) quantities within registers or memories of a processing system into other data similarly represented as physical quantities within memories, registers, or other such information storage, transmission, or display devices of the processing system. Information and signals may be represented using any of a variety of different techniques and methods. For example, data, instructions, commands, information, signals, bits, symbols, and chips mentioned throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, light fields or particles, or any combination thereof.

[0243] It should be understood that the specific order or hierarchy of steps in the disclosed process is an example of an exemplary method. Based on design preferences, it should be understood that the specific order or hierarchy of steps in the process can be rearranged without departing from the scope of protection of the present disclosure. The attached method claims present the elements of the various steps in an exemplary order and are not intended to be limited to the specific order or hierarchy described.

[0244] In the above detailed description, various features are grouped together in a single embodiment to simplify the disclosure. This method of disclosure should not be interpreted as reflecting an intention that the embodiments of the claimed subject matter require more features than are clearly stated in each claim. On the contrary, as reflected in the appended claims, the invention is in a state of having less than all the features of the disclosed individual embodiments. Therefore, the appended claims are hereby expressly incorporated into the detailed description, with each claim standing on its own as a separate preferred embodiment of the invention.

[0245] Those skilled in the art will also appreciate that the various illustrative logic blocks, modules, circuits, and algorithmic steps described in conjunction with the embodiments herein can all be implemented as electronic hardware, computer software, or a combination thereof. In order to clearly illustrate the interchangeability between hardware and software, various illustrative components, blocks, modules, circuits, and steps are generally described above around their functions. Whether such functions are implemented as hardware or software depends on specific applications and the design constraints imposed on the entire system. A skilled person can implement the described functions in an alternative manner for each specific application, but such implementation decisions should not be interpreted as departing from the scope of protection of the present disclosure.

[0246] The steps of the method or algorithm described in conjunction with the embodiments herein may be directly embodied as hardware, a software module executed by a processor, or a combination thereof. The software module may be located in a RAM memory, a flash memory, a ROM memory, an EPROM memory, an EEPROM memory, a register, a hard disk, a mobile disk, a CD-ROM, or any other form of storage medium well known in the art. An exemplary storage medium is connected to the processor so that the processor can read information from the storage medium and can write information to the storage medium. Of course, the storage medium may also be an integral part of the processor. The processor and the storage medium may be located in an ASIC. The ASIC may be located in a user terminal. Of course, the processor and the storage medium may also be present in a user terminal as discrete components.

[0247] For software implementation, the techniques described in this application can be implemented with modules (e.g., procedures, functions, etc.) that perform the functions described in this application. These software codes can be stored in a memory unit and executed by a processor. The memory unit can be implemented within the processor or outside the processor. In the latter case, it is coupled to the processor in a communication manner via various means, which are well known in the art.

[0248] The above description includes examples of one or more embodiments. Of course, it is impossible to describe all possible combinations of components or methods for the purpose of describing the above embodiments, but it should be recognized by those skilled in the art that the various embodiments may be further combined and arranged. Therefore, the embodiments described herein are intended to cover all such changes, modifications and variations that fall within the scope of protection of the appended claims. In addition, with respect to the term "comprising" used in the specification or claims, the word is covered in a manner similar to the term "including", just as "including," is explained as a transitional word in the claims. In addition, any term "or" used in the specification of the claims is intended to mean "non-exclusive or".

Claims

1. A method for evaluating the safety of underground water seal caverns during their entire life cycle, characterized in that: include: During the cavern construction, the first hydrological monitoring data and the water curtain system experimental data are obtained, the data evolution trend and data distribution range of the first hydrological monitoring data and the water curtain system experimental data are analyzed, and the potential risk area is predicted according to the data evolution trend and data distribution range; Before the cavern is put into operation, based on the air tightness experiment of the potential risk area, the second hydrological monitoring data before the cavern is put into operation is obtained and analyzed, wherein the second hydrological monitoring data includes the surrounding rock fissure water pressure; During the operation of the cavern, monitor the third hydrological monitoring data and water curtain water supply system data of the potential risk areas; The third hydrological monitoring data includes natural groundwater level data, hydraulic balance data and groundwater quality data; According to the second hydrological monitoring data, the third hydrological monitoring data and the water curtain water supply system data, based on the pre-constructed water seal safety evaluation system, the local dynamic risk levels of different risk indicators in the potential risk area are determined, and the overall risk level of the cavern is determined based on the local dynamic risk levels.

2. The method according to claim 1, characterized in that The obtaining of the first hydrological monitoring data and the water curtain system experimental data includes: Collect the first hydrological monitoring data and water curtain system experimental data; The first hydrological monitoring data includes at least one of groundwater level and water quality data, atmospheric pressure and precipitation data, pore water pressure data, seepage points in the cave and seepage point characteristic data, construction water consumption and drainage data; The water curtain system experimental data includes at least one of the water supply data of the water curtain tunnel and the water curtain hole and the water injection quality data of the water curtain hole; The water curtain system experiment includes at least one of a single-hole water pressure test, an effectiveness test, and a comprehensive hydraulic test.

3. The method according to claim 1, characterized in that Based on the airtightness experiment of the potential risk area, the second hydrological monitoring data before the cavern operation is obtained and analyzed, including: Conducting an airtightness test on the potential risk area and collecting second hydrological monitoring data during the airtightness test, wherein the second hydrological monitoring data includes groundwater level data and pressure data; the pressure data includes surrounding rock fissure water pressure; The groundwater level data and pressure data are analyzed.

4. The method according to claim 1, characterized in that Also includes: Before conducting an airtightness test on a potential risk area, determine whether the following test conditions are met. If so, conduct an airtightness test: The underground cavern has been completed and passed the acceptance inspection; The shaft installation project and equipment commissioning have been completed and passed the acceptance inspection; The cavern tanks in the cavern have been calibrated; The groundwater level and pressure monitoring system has been installed and commissioned, and data recording has begun.

5. The method according to claim 4, characterized in that The air tightness test includes a preparation stage, a gas injection and pressure increase stage, a pressure stabilization stage, and a detection and determination stage: In the preparation stage, water is injected into the construction tunnel, water curtain tunnel and shaft, instruments and equipment whose measuring range and accuracy technical requirements meet the needs of air tightness test analysis and determination are prepared and debugged, and monitoring instruments are started, which include at least one of groundwater level, water pressure, initial temperature in the cave tank and liquid level monitoring instruments in the cave tank; During the gas injection and pressure-increasing stage, the test gas is injected into the test cave tank at a preset gas pressure-increasing rate, and the temperature and pressure of the injected gas are controlled, and the monitoring index data of the cave tank is measured and recorded at a preset frequency; During the pressure stabilization stage, the difference between the gas pressure in the cavern and the preset test pressure is controlled to be no greater than the set pressure threshold. When the difference is greater than the set pressure threshold, the gas pressure in the cavern is adjusted by injecting gas, and the monitoring index data of the cavern is measured and recorded at a preset frequency; During the detection and judgment stage, the monitoring index data of the cavern is measured and recorded at a preset frequency, and the real-time change data of the test gas pressure in the cavern is determined based on the temperature change data in the cavern, the gas volume change data caused by the liquid level change in the pump pit, and the amount of air dissolved in the fissure water; the real-time change data at different times are compared with the initial pressure data of this stage. If the change is not greater than the preset allowable change, the air tightness of the cavern is determined to be qualified.

6. The method according to claim 1, characterized in that The method of determining the local dynamic risk level of different risk indicators in the potential risk area based on the second hydrological monitoring data, the third hydrological monitoring data and the water curtain water supply system data based on the pre-built water seal safety evaluation system, and determining the overall risk level of the cavern based on the local dynamic risk level, includes: Determine the dynamic risk level of surrounding rock fissure water pressure based on the surrounding rock fissure water pressure in the second hydrological monitoring data and the pre-established surrounding rock fissure water pressure evaluation system; Determine the dynamic risk level of natural groundwater level based on the natural groundwater level data in the third hydrological monitoring data and the pre-established natural groundwater level evaluation system; Determine the hydraulic balance dynamic risk level based on the hydraulic balance data in the third hydrological monitoring data and the pre-established hydraulic balance evaluation system; Determine the dynamic risk level of groundwater quality based on the groundwater quality data in the third hydrological monitoring data and the pre-established groundwater quality evaluation system; Determine the dynamic risk level of the water curtain water level based on the water curtain water level data in the water curtain water supply system data and the pre-established water curtain water level evaluation system; The dynamic risk level of surrounding rock fissure water pressure, the dynamic risk level of natural groundwater level, the dynamic risk level of hydraulic balance, the dynamic risk level of groundwater quality and the dynamic risk level of water curtain water level are weighted and comprehensively processed to obtain the overall risk level of the cavern.

7. The method according to claim 6, characterized in that Determining the dynamic risk level of surrounding rock fissure water pressure according to the surrounding rock fissure water pressure in the second hydrological monitoring data and a pre-established surrounding rock fissure water pressure evaluation system includes: Obtaining the surrounding rock fissure water pressure monitored by the piezometer installed in the pressure gauge hole, determining the water potential change according to the surrounding rock fissure water pressure, analyzing the correlation between the slurry spreading and seepage in the underground water-sealed cavern according to the water potential change, and establishing a surrounding rock fissure water pressure evaluation system according to the correlation between the slurry spreading and seepage in the underground water-sealed cavern; The establishment of the surrounding rock fissure water pressure evaluation system includes: establishing the magnitude relationship between the surrounding rock fissure water pressure monitored by the piezometer and the pressure in the pressure stabilization stage of the air tightness experiment, and the quantitative ratio of the head loss quantitative index FLF of the surrounding rock fissure water pressure monitored by the piezometer tending to a specified value, and establishing the corresponding relationship between the magnitude relationship, the quantitative ratio and the dynamic risk level of the surrounding rock fissure water pressure; The FLF=(H w -H c ) / (H w -H s ), where FLF is the friction loss coefficient, H w is the water head of the water curtain tunnel, H c H is the head of surrounding rock fissure water pressure converted based on the piezometer reading; s It is the vault water head of the oil storage cavern.

8. The method according to claim 6, characterized in that Determining the natural groundwater level dynamic risk level according to the natural groundwater level data in the third hydrological monitoring data and the pre-established natural groundwater level evaluation system includes: Obtaining natural groundwater level data monitored by a piezometer installed in the pressure gauge hole, and establishing a natural groundwater level evaluation system based on the natural groundwater level data; The establishment of the natural groundwater level evaluation system includes: establishing a first high-low relationship between the natural groundwater level monitored by the piezometer and the designed groundwater level, and establishing a corresponding relationship between the first high-low relationship, the leakage signs of surrounding oil and gas, and the dynamic risk level of the natural groundwater level; The natural groundwater level meets the following formula: H l =P c ×100+H0≥H d , where H l is the natural groundwater level, which is the water head value converted based on the piezometer reading, P c Osmometer reading, H0—Osmometer installation height, H d Design groundwater level.

9. The method according to claim 6, characterized in that Determining the hydraulic balance dynamic risk level according to the hydraulic balance data in the third hydrological monitoring data and the pre-established hydraulic balance evaluation system includes: Obtain the cavern drainage, water inflow and water replenishment of the water curtain system, use the cavern drainage and water replenishment of the water curtain system as hydraulic balance data, evaluate the hydraulic balance of the cavern based on the hydraulic balance data and establish a hydraulic balance evaluation system; The establishment of the hydraulic balance evaluation system includes: establishing the corresponding relationship between the drainage volume of the cavern, the excess ratio of the water replenishment volume of the water curtain system, and the excess ratio of the water inflow volume of the cavern and the dynamic risk level of the hydraulic balance.

10. The method according to claim 6, characterized in that Based on the groundwater quality data in the third hydrological monitoring data and the pre-established groundwater quality evaluation system, the groundwater quality dynamic risk level is determined, including: Obtain groundwater quality data and establish a groundwater quality evaluation system based on the groundwater quality data; The establishment of the groundwater quality evaluation system includes: obtaining the degree of proximity between the physical indicators, chemical indicators, and bacterial indicators of groundwater quality and the corresponding indicators in the water quality monitoring report before the operation of the cavern, and establishing a corresponding relationship between the degree of proximity, changes in the color and odor of the water body, and the dynamic risk level of groundwater quality.

11. The method according to claim 6, characterized in that According to the water curtain water level data in the water curtain water supply system data and the pre-established water curtain water level evaluation system, the dynamic risk level of the water curtain water level is determined, including: Acquire water curtain water level data monitored by a piezometer installed in the pressure gauge hole, and establish a water curtain water level evaluation system according to the water curtain water level data; The establishment of the water curtain water level evaluation system includes: establishing a second high-low relationship between the water curtain water level height monitored by the piezometer and the designed water curtain water level height, and establishing a corresponding relationship between the second high-low relationship, changes in surrounding rock fissure water pressure, signs of surrounding oil and gas leakage and the dynamic risk level of the water curtain water level.

12. A device for evaluating the safety of underground water seal caverns during their entire life cycle, characterized in that: include: The data acquisition module is used to obtain hydrological monitoring information of underground water-sealed caverns and experimental data of water curtain systems during the construction period; to obtain and analyze hydrological information of underground water-sealed caverns and surrounding rock fissure water pressure before operation; and to obtain geological data of the entire life cycle of underground water-sealed caverns during operation; The water seal safety evaluation module is used to analyze the evolution trend and distribution range of historical data based on hydrological monitoring information and water curtain system experimental data, and predict future potential risk areas based on the evolution trend of the historical data; establish a risk identification and evaluation system for surrounding rock fissure water pressure; determine the water seal safety evaluation system based on the real-time monitored geological data obtained by the data acquisition module and divide the dynamic risk level of the underground water seal cavern throughout its life cycle.

13. A computer storage medium, characterized in that: The computer storage medium stores computer executable instructions, which, when executed by the processor, implement the method for evaluating the water seal safety of an underground water seal cavern throughout its life cycle as described in any one of claims 1-11.

14. A computer device, characterized in that: include: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor, when executing the program, implements the method for evaluating the safety of underground water seals in the entire life cycle of water seal caverns as described in any one of claims 1 to 11.

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