Method and device for evaluating water sealing safety of whole life cycle of underground water-sealed storage

Abstract

The application discloses a kind of whole life cycle water seal safety evaluation method and device of underground water seal cavern, the method includes: during the construction of cavern, first hydrological monitoring data and water curtain system experimental data are obtained and analyzed, potential risk area is predicted;Before the operation of cavern, based on the air tightness experiment of potential risk area, obtain the second hydrological monitoring data before the operation of cavern and carry out analysis;During the operation of cavern, the third hydrological monitoring data and water curtain water supply system data of potential risk area are monitored, according to second hydrological monitoring, third hydrological monitoring data and water curtain water supply system data, based on the water seal safety evaluation system that is constructed in advance, the overall risk level of cavern is determined.Can the data of whole life cycle of cavern be monitored and the safety evaluation result is obtained by correlation analysis to data, the risk of water seal cavern is identified in time, and the accuracy and reliability of evaluation result are high, and it is convenient to operate, low in cost, provide important reference data for underground water seal engineering.

Description

Technical Field

[0001] This invention relates to the field of underground water-sealed cavern technology, and in particular to a method and apparatus for evaluating the safety of water seal throughout the entire life cycle of underground water-sealed caverns. Background Technology

[0002] Underground water-sealed oil caverns are characterized by their large scale, numerous excavation faces, frequent overlapping operations, and strict requirements for groundwater level control. Analysis of the construction and operation of existing caverns both domestically and internationally reveals that during construction, instability and collapse of the surrounding rock in structurally fractured areas, and a drop in groundwater levels exceeding warning levels, coupled with blasting operations in the main cavern exacerbating surrounding rock damage and creating dense water-conducting channels, all negatively impact the construction and operation of underground water-sealed caverns to varying degrees. This demonstrates that the realization of their function depends not only on the stability of the underground structure but also on the safety of the water seal. Risks exposed during the construction and operation of underground water-sealed oil caverns can often lead to serious consequences. Therefore, it is necessary to promptly identify water seal safety risks in underground water-sealed caverns and implement corresponding risk mitigation measures.

[0003] The water seal safety monitoring of existing underground water-sealed caverns mostly adopts single-item monitoring technology, such as analyzing each data point separately, including groundwater level, water inflow, and surrounding rock fissure water pressure, to achieve water seal safety monitoring. Summary of the Invention

[0004] The water-sealing characteristics of underground oil storage facilities dictate the complexity and difficulty of their monitoring technology. The inventors of this application have discovered that current methods typically employ single-data monitoring techniques to monitor the water-sealing safety of underground water-sealed caverns. These methods lack in-depth data mining and utilization, and the analysis of monitoring data does not consider the correlation between data points, failing to establish a comprehensive safety monitoring and evaluation system that links data together. This results in poor accuracy of monitoring results for the water-sealing safety of underground water-sealed caverns, hindering timely identification of risks and effective risk assessment and safety control. In short, existing technologies lack a systematic, full-lifecycle management technology framework, restricting the implementation of water-sealing safety monitoring for underground water-sealed caverns. Therefore, it is necessary to create a full-lifecycle water-sealing safety monitoring and risk assessment method to promptly identify and control risk sources, ensuring the safe construction of underground rock cavern storage facilities.

[0005] In view of the above problems, the present invention is proposed to provide a method and apparatus for full life cycle water seal safety evaluation of underground water-sealed caverns that overcomes or at least partially solves the above problems.

[0006] In a first aspect, embodiments of the present invention provide a method for evaluating the safety of water seals throughout the entire life cycle of underground water-sealed caverns, including:

[0007] During the construction of the cavern, first hydrological monitoring data and water curtain system experimental data were acquired, and the data evolution trend and data distribution range of the first hydrological monitoring data and water curtain system experimental data were analyzed. Based on the data evolution trend and data distribution range, potential risk areas were predicted.

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

[0009] During the operation of the cavern, third-party hydrological monitoring data and water curtain water supply system data are monitored for potential risk areas; third-party hydrological monitoring data includes natural groundwater level data, hydraulic balance data, and groundwater quality data;

[0010] Based on the second and third hydrological monitoring data and the water curtain water supply system data, and 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.

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

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

[0013] The first hydrological monitoring data includes at least one of the following: groundwater level and water quality data, atmospheric pressure and precipitation data, pore water pressure data, seepage point data and seepage point characteristics data, and construction water consumption and drainage data.

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

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

[0016] In some optional embodiments, based on airtightness tests on potentially risky areas, second hydrological monitoring data is obtained and analyzed before the cavern is put into operation, including:

[0017] An airtightness test was conducted on the potential risk area, and secondary hydrological monitoring data was collected during the airtightness test. The secondary hydrological monitoring data included groundwater level data and pressure data; the pressure data included the pressure of water in the surrounding rock fissures.

[0018] Analyze the groundwater level and pressure data.

[0019] In some optional embodiments, the method further includes: before conducting an airtightness test on a potentially risky area, determining whether the following experimental conditions are met; if so, then conducting the airtightness test:

[0020] The underground cavern has been completed and passed inspection.

[0021] The installation and commissioning of the vertical shaft have been completed and passed inspection.

[0022] The cave tanks inside the cave have been calibrated;

[0023] The groundwater level and pressure monitoring system has been installed, debugged, and is now recording data.

[0024] In some optional embodiments, the airtightness test includes a preparation phase, a pressurization phase, a pressure stabilization phase, and a detection and judgment phase:

[0025] During the preparation phase, water is injected into the construction tunnels, water curtain tunnels, and vertical shafts. Instruments with measurement range and accuracy technical requirements that meet the needs of airtightness test analysis and judgment are prepared and debugged. Monitoring instruments are started, including at least one of the following: groundwater level, water pressure, initial temperature inside the tunnel, and liquid level inside the tunnel.

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

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

[0028] During the testing and judgment phase, the monitoring index data of the cavern are measured and recorded at a preset frequency. Based on the temperature change data inside 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 of the test gas pressure inside the cavern are determined. The real-time change data at different times are compared with the initial pressure data of this phase. If the change is not greater than the preset allowable change, the airtightness of the cavern is determined to be qualified.

[0029] In some optional embodiments, based on second hydrological monitoring data, third hydrological monitoring data, and water curtain water supply system data, and based on a 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:

[0030] 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, the dynamic risk level of surrounding rock fissure water pressure is determined.

[0031] Based on the natural groundwater level data in the third hydrological monitoring data and the pre-established natural groundwater level evaluation system, the dynamic risk level of the natural groundwater level is determined.

[0032] Based on the hydraulic balance data in the third hydrological monitoring data and the pre-established hydraulic balance evaluation system, the dynamic risk level of hydraulic balance is determined.

[0033] Based on the groundwater quality data in the third hydrological monitoring data and the pre-established groundwater quality assessment system, the dynamic risk level of groundwater quality is determined.

[0034] Based on the water level data in the water curtain water supply system and the pre-established water curtain water level evaluation system, the dynamic risk level of the water curtain water level is determined.

[0035] The overall risk level of the cavern is obtained by weighting and comprehensively processing the dynamic risk levels of surrounding rock fissure water pressure, natural groundwater level, hydraulic balance, groundwater quality, and water curtain level.

[0036] In some optional embodiments, the dynamic risk level of the surrounding rock fissure water pressure is determined based on the surrounding rock fissure water pressure in the second hydrological monitoring data and a pre-established surrounding rock fissure water pressure evaluation system, including:

[0037] The pressure of the surrounding rock fissure water is obtained by monitoring the piezometer installed in the pressure gauge hole. The water potential change is determined based on the pressure of the surrounding rock fissure water. The correlation between the slurry spread and seepage in the underground water-sealed cavern is analyzed based on the water potential change. Based on the correlation between the slurry spread and seepage in the underground water-sealed cavern, an evaluation system for the surrounding rock fissure water pressure is established.

[0038] The establishment of a surrounding rock fissure water pressure evaluation system includes: establishing the relationship between the surrounding rock fissure water pressure monitored by the piezometer and the pressure during the pressure stabilization stage of the airtightness test, as well as the proportion of the number of times the head loss quantitative index (FLF) of the surrounding rock fissure water pressure monitored by the piezometer tends to a specified value, and establishing the correspondence between the above relationship, the above proportion 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 For the water head of the water curtain tunnel, H cH is the hydraulic head calculated based on piezometer readings of the surrounding rock fissure water pressure; s The water head at the vault of the oil storage cavern.

[0040] In some optional embodiments, the dynamic risk level of the natural groundwater 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:

[0041] Natural groundwater level data were obtained by monitoring the piezometer installed in the pressure gauge hole, and a natural groundwater level evaluation system was established based on the natural groundwater level data.

[0042] Establishing a natural groundwater level evaluation system includes: establishing the primary high-low relationship between the natural groundwater level obtained from piezometer monitoring and the design groundwater level, as well as establishing the correspondence between the above primary high-low relationship, signs of leakage 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 H l The natural groundwater level is the head value calculated based on piezometer readings, P. c Piezometer reading, H0—Piercing height of the piezometer, H d To design the groundwater level.

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

[0045] Obtain the cavern's drainage volume, inflow volume, and water replenishment volume of the water curtain system. Use the cavern's drainage volume and water replenishment volume of the water curtain system as hydraulic balance data. Evaluate the hydraulic balance status of the cavern based on the hydraulic balance data and establish a hydraulic balance evaluation system.

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

[0047] In some optional embodiments, the dynamic risk level of groundwater quality is determined based on groundwater quality data from third-party hydrological monitoring data and a pre-established groundwater quality assessment system, including:

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

[0049] Establishing a groundwater quality assessment system includes: obtaining the physical, chemical, and bacterial indicators of groundwater and comparing them with the corresponding indicators in the water quality monitoring report before the cavern's operation; and establishing the correspondence between the above-mentioned similarity, 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 level is determined based on the water curtain level data in the water curtain supply system data and a pre-established water curtain level evaluation system, including:

[0051] The water level data of the water curtain is obtained by the piezometer installed in the pressure gauge hole, and a water curtain water level evaluation system is established based on the water curtain water level data;

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

[0053] Secondly, embodiments of the present invention provide a device for evaluating the safety of water seals throughout the entire life cycle of underground water-sealed caverns, comprising:

[0054] The data acquisition module is used to acquire hydrological monitoring information and experimental data of the water curtain system of the underground water-sealed cavern during the construction period; to acquire and analyze hydrological information and surrounding rock fissure water pressure of the underground water-sealed cavern before operation; and to acquire geological data of the underground water-sealed cavern throughout its entire life cycle 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 experimental data of the water curtain system, and predict potential risk areas in the future based on the evolution trend of historical data; establish a risk identification and evaluation system for water pressure in surrounding rock fissures; and determine the water seal safety evaluation system and classify the dynamic risk level of the underground water-sealed cavern throughout its entire life cycle based on the real-time monitoring geological data obtained by the data acquisition module.

[0056] This invention provides a computer storage medium storing computer-executable instructions. When these computer-executable instructions are executed by a processor, a method for evaluating the safety of water-sealed underground water-sealed caverns throughout their entire life cycle is implemented.

[0057] This 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, it implements a method for evaluating the safety of water-sealed underground caverns throughout their entire life cycle.

[0058] The beneficial effects of the above-described technical solutions provided in the embodiments of the present invention include at least the following:

[0059] During the construction of the cavern, the first hydrological monitoring data and the experimental data of the water curtain system are monitored to predict potential risk areas. Before the cavern is put into operation, the second hydrological monitoring data is obtained based on the airtightness test of the potential risk areas. During the operation of the cavern, the third hydrological monitoring data and the water curtain water supply system data of the potential risk areas are monitored. Based on the data monitoring and analysis of the entire life cycle of the cavern, including construction, pre-operation and operation, the risk level of the cavern is evaluated based on the pre-constructed water seal safety evaluation system. The aforementioned method utilizes multiple technologies, including hydrological monitoring and evaluation, water curtain system testing, airtightness testing, and cavern operation and maintenance, to deeply explore and utilize the correlations of monitoring data across different lifecycles. Based on a water seal safety monitoring system for underground water-sealed caverns that spans the entire construction and operation phases, it effectively integrates various monitoring data, including natural groundwater level, water curtain level, surrounding rock fissure water pressure data, hydraulic balance data, and groundwater quality data. This allows for the identification, classification, and evaluation of the cavern's risk level, enabling timely identification of risks and obtaining accurate and reliable evaluation results, thus ensuring the long-term, stable, and safe operation of underground water-sealed caverns. This method boasts advantages such as a full lifecycle approach, strong targeting, high reliability, ease of operation, low cost, and wide applicability. It addresses the discontinuity and limitations of existing water seal monitoring methods used in caverns, allowing for appropriate adjustment of parameter settings in the constructed water seal safety evaluation system based on actual working conditions, enabling fine-tuning of risk levels. This method has significant application value for various underground engineering and underground space projects, including underground water-sealed caverns.

[0060] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the written description, claims, and drawings.

[0061] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0062] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0063] Figure 1 This is a flowchart of the water seal safety evaluation method for underground water-sealed caverns in an embodiment of the present invention;

[0064] Figure 2 This is a statistical chart of groundwater level changes in an embodiment of the present invention;

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

[0066] Figure 4 This is a statistical chart of water inflow in an embodiment of the present invention;

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

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

[0069] Figure 7 This is an example diagram illustrating a blockage around the cavern in an embodiment of the present invention;

[0070] Figure 8 This is a structural diagram of the underground water-sealed cavern full life cycle water seal safety evaluation device in an embodiment of the present invention. Detailed Implementation

[0071] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0072] The water-sealing characteristics of underground oil storage facilities determine the complexity and difficulty of their monitoring technology. The inventors of this application have found that current methods typically use single-data monitoring to monitor the water-sealing safety of underground water-sealed caverns. The monitoring data is not deeply mined and utilized, and the correlation between data is not considered during analysis. A safety monitoring and evaluation system with interconnected data has not been formed, resulting in poor accuracy of the monitoring results for the water-sealing safety of underground water-sealed caverns. It is impossible to identify the risks of water-sealed caverns in a timely manner, and it is impossible to effectively conduct risk assessment and safety control.

[0073] To address the problem of the lack of a data-linked safety evaluation system for underground water-sealed caverns in existing technologies, this invention provides a full life-cycle safety evaluation method for underground water-sealed caverns. This method can promptly identify and control risk sources. It has advantages such as being applicable to the entire life cycle, highly targeted, highly reliable, easy to operate, low in cost, and widely applicable, and is of great significance for ensuring the safe construction and operation of underground cavern storage facilities.

[0074] Example

[0075] This invention provides a method for evaluating the safety of water seals in underground water-sealed caverns, the process of which is as follows: Figure 1 As shown, it includes the following steps:

[0076] Step S101: During the construction of the cavern, acquire the first hydrological monitoring data and the experimental data of the water curtain system, analyze the data evolution trend and data distribution range of the first hydrological monitoring data and the experimental data of the water curtain system, and predict potential risk areas based on the data evolution trend and data distribution range.

[0077] Step S102: Before the operation of the cavern, based on the airtightness test of the potential risk area, the second hydrological monitoring data before the operation of the cavern is obtained and analyzed. The second hydrological monitoring data includes the water pressure in the surrounding rock fissures.

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

[0079] Step S104: Based on the second hydrological monitoring data, the third hydrological monitoring data, and the water curtain water supply system data, and 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 step S101 above, obtaining the first hydrological monitoring data and the water curtain system experimental data includes:

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

[0082] The first hydrological monitoring data includes at least one of the following: groundwater level and water quality data, atmospheric pressure and precipitation data, pore water pressure data, seepage point data and seepage point characteristics data, and construction water consumption and drainage data.

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

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

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

[0086] 1) Groundwater level and water quality

[0087] Utilize the existing monitoring network in well-preserved exploration boreholes to monitor groundwater levels and water quality. Before construction, verify the location, bottom elevation, and integrity of each borehole to ensure data conversion is feasible. If some boreholes are damaged, drill additional boreholes nearby and perform data conversion and borehole opening protection.

[0088] 2) Atmospheric pressure and precipitation

[0089] Measure local atmospheric pressure and precipitation, and conduct actual measurements in the site area in accordance with the meteorological department's regulations.

[0090] 3) Pore water pressure

[0091] Underground pressure gauge boreholes are installed in the water curtain boreholes of the water curtain tunnel. The pore water pressure is measured using instruments in these boreholes. The underground pressure gauge boreholes are divided into three types: inclined, horizontal, and vertical. Initially, 50 underground pressure gauge boreholes were installed. Specifically: boreholes numbered 1-30 are horizontal underground pressure gauge boreholes drilled from the water curtain tunnel, with a downward inclination angle of 2%; boreholes numbered 31-40 are vertical underground pressure gauge boreholes drilled from the water curtain tunnel, with the bottom elevation 10m below the floor of the oil storage chamber; boreholes numbered 41-50 are inclined underground pressure gauge boreholes drilled from the water curtain tunnel, with an inclination angle of 30° to the vertical plane, and the bottom elevation 10m below the floor of the oil storage chamber. The number of underground pressure gauge boreholes, their bottom elevations, and their inclination angles can be adjusted appropriately based on actual construction conditions.

[0092] 4) Data describing seepage points and characteristics within the tunnel

[0093] Measuring and recording the seepage volume during and after the excavation of each oil storage cavern, connecting roadway, shaft, construction roadway, and water curtain roadway. Daily measurements of the corresponding mileage and seepage volume at each seepage point, and completion of characteristic descriptions of seepage points within underground caverns, such as monitoring the flow rate, source, conductivity, odor, and color of the seepage points.

[0094] 5) Construction water consumption and drainage volume

[0095] Measuring and recording the amount of construction water and drainage supplied from the outside to each main unit of the underground project during the construction process.

[0096] Experimental data of the water curtain system in this embodiment of the invention include:

[0097] 1) Water supply from water curtain tunnels and water curtain orifices

[0098] 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 measured and recorded separately during the construction process. During the water injection process of the water curtain holes, the water injection flow rate and water injection pressure of each water curtain hole are measured and recorded.

[0099] 2) Water injection quality of the water curtain hole

[0100] Water quality samples are taken and analyzed regularly from the water curtain supply pipeline to evaluate the physical, chemical, and bacterial characteristics of the water supply.

[0101] After collecting primary hydrological monitoring data and water curtain system experimental data, we focus on analyzing areas where the primary hydrological monitoring data is abnormal or where regional precipitation funnels appear. Based on the data evolution trend and distribution range, we predict potential risk areas. Figure 2 This is a graph showing changes in groundwater levels. Figure 2 The horizontal axis represents the date, and the vertical axis represents the water level elevation. The curves in the graph represent the water level changes in the underground pressure gauge orifices. See also Figure 2 As shown, the area within 200m of the borehole where the groundwater level has been consistently lower than the allowable water level during construction is considered a potential risk zone. The allowable water level during construction is shown in [reference needed]. Figure 2 The horizontal line at the 10m mid-water level indicates the location of this potential risk area, which should be marked and closely monitored and evaluated during the operational period. Figure 3 This is a graph showing the changes in pore water pressure. Figure 3 The horizontal axis represents the water curtain hole number, and the vertical axis represents the pore water pressure. Pore water pressure is monitored in three stages. During the effectiveness test, the area within 200m of the dark-colored pentagram water curtain hole with pressure lower than the theoretical value is considered a risk zone. This area should be marked and closely monitored and evaluated during the operational period. (See the dark-colored pentagram for details.) 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 diagram. The upper line represents the theoretical value of pore water pressure in stage 1, and the lower line represents the theoretical value of pore water pressure in stage 2 / 3.

[0102] During the initial operation phase, the water inflow of each oil storage chamber should be measured separately. See the water inflow statistics chart below. Figure 4 As shown, Figure 4 The data records the water inflow of several caverns over several days. Calculations show that if the water inflow exceeds the standard, the oil storage cavern should be marked and should be closely monitored and evaluated during the operation period.

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

[0104] An airtightness test was conducted on the potential risk area, and secondary hydrological monitoring data was collected during the airtightness test. The secondary hydrological monitoring data included groundwater level data and pressure data; the pressure data included the pressure of water in the surrounding rock fissures.

[0105] Analyze the groundwater level and pressure data.

[0106] Preferably, before conducting an airtightness test on a potentially risky area, it should be determined whether the following test conditions are met; if so, the airtightness test should then be conducted:

[0107] The underground cavern has been completed and passed inspection.

[0108] The installation and commissioning of the vertical shaft have been completed and passed inspection.

[0109] The underground tanks inside the cavern have been calibrated; the pump pits inside the underground tanks also need to be calibrated.

[0110] The groundwater level and pressure monitoring system has been installed, debugged, and is now recording data.

[0111] The hydrological monitoring data during the airtightness 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 phase. If the pressure change after correction during the airtightness test is not greater than the design allowable value, the airtightness of the cavern / tank can be judged as qualified. However, if the fissure water pressure values ​​of the surrounding rock monitored by some pressure gauge holes are lower than the theoretical values ​​calculated by the seepage field, the area should be marked as a leakage risk zone during the operation period.

[0112] The airtightness test is conducted in separate tanks, or multiple tanks or all tanks simultaneously. The medium used for the airtightness test is air or an inert gas. The test pressure is 1.05 times the maximum design pressure of the tank.

[0113] Preferably, the airtightness test includes a preparation stage, an air injection and pressurization stage, a pressure stabilization stage, and a detection and judgment stage.

[0114] Preferably, in the preparation stage, water is injected into the construction tunnel, water curtain tunnel and vertical shaft; instruments with measurement range and accuracy technical requirements that meet the needs of airtightness test analysis and judgment are prepared and debugged; and monitoring instruments are started. The monitoring instruments include at least one of the following: groundwater level, water pressure, initial temperature inside the tunnel, and liquid level inside the tunnel.

[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 pressurization are carried out simultaneously, the water level at the top of the cavern should be maintained at 102P+25m, where P is the cavern pressure in MPa. After the water injection is completed, the water level should reach or exceed the design groundwater level elevation during operation.

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

[0117] In this embodiment, during the gas injection and pressurization stage, the pressurization rate of the gas injected into the test chamber should not exceed 30 kPa / d, and the temperature of the test gas injected into the chamber should be 2-3°C lower than the stable operating temperature of the chamber. Injection should be stopped immediately when the test gas pressure inside the chamber reaches the test pressure. The items and frequencies of measurements recorded during the gas injection and pressurization stage should comply with the provisions of Table 1.

[0118] Table 1

[0119] Serial Number Measurement Record Items Measurement recording frequency 1 Gas pressure inside the cavern Record once every 2 hours. 2 Atmospheric pressure Record once every 2 hours. 3 Compressed air injection temperature Record once every 2 hours. 4 Temperature inside the test chamber Record once every 2 hours. 5 Liquid level in the test tank Record once every 2 hours. 6 Liquid level in the test tank pump pit Record once every 2 hours. 7 Water level above the shaft seal plug Record twice a day 8 Groundwater monitoring well water level Record twice a day 9 Rock fissure water pressure Record 4 times a day

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

[0121] After the gas injection and pressurization phase, the pressure stabilization phase begins. In this embodiment, the cavern temperature is considered stable when the temperature change inside the cavern does not exceed ±0.1℃ / d. During the pressure stabilization process of the test gas inside the cavern, the gas pressure inside the cavern should be kept the same as the test pressure. When the gas pressure inside the cavern decreases, an appropriate amount of gas can be injected. The surrounding rock fissure water pressure value during the pressure stabilization phase of the airtightness test is an important basic parameter for monitoring the surrounding rock fissure water pressure during the cavern's operation and should be recorded, preserved, and archived in detail. The items and frequency of measurement records during the pressure stabilization phase should comply with the provisions of Table 2.

[0122] Table 2

[0123] Serial Number Measurement Record Items Measurement recording frequency 1 Gas pressure inside the cavern Record once every 1 hour 2 Atmospheric pressure Record once every 1 hour 3 The volume of fissure water discharged from the cavity. Real-time recording 4 Temperature inside the test chamber Record once every 1 hour 5 Liquid level in the test tank Record once every 1 hour 6 Liquid level in the test tank pump pit Record once every 1 hour 7 Water level above the shaft seal plug Record twice a day 8 Surface hydrological monitoring well water level Record twice a day 9 Rock fissure water pressure Record 4 times a day

[0124] Preferably, in the detection and judgment stage, the monitoring index data of the cavern are measured and recorded at a preset frequency. Based on the temperature change data inside 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 of the test gas pressure inside the cavern are determined. 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 airtightness of the cavern is determined to be qualified.

[0125] After the pressure stabilization phase, the testing and judgment phase begins. In this embodiment, the testing and judgment phase lasts for no less than 100 hours. The items and frequencies of measurement records during the testing and judgment phase must comply with the requirements of Table 1 or Table 2. During this phase, the measured test gas pressure values ​​inside the cavern should be corrected based on the temperature changes inside the cavern, the gas volume changes caused by the liquid level changes in the pump pit, and the amount of air dissolved in the fissure water. If the corrected pressure value is compared with the initial pressure value of this phase, and the change is not greater than the design allowable value, the cavern's airtightness can be determined to be qualified.

[0126] The gas pressure changes caused by temperature changes inside the tank and liquid level changes in the pump pit can be calculated using the ideal gas law.

[0127] When calculating the impact of gas dissolved in the water cushion layer on the gas pressure of the tunnel tank, the amount of air dissolved in the water is calculated using Table 3.

[0128] Table 3

[0129]

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

[0131] Monitoring data on natural groundwater levels, including surface hydrological monitoring well levels and shaft levels; the surface hydrological monitoring well levels are monitored by installing piezometers inside the wells, and the shaft levels are monitored by installing piezometers in the shafts.

[0132] Monitor hydraulic balance data, assess the hydraulic balance of the reservoir area by measuring the drainage volume of the underground water-sealed cavern and the water replenishment volume of the water curtain system; monitor the water replenishment and drainage volume of the underground water-sealed cavern by installing flow meters in the water replenishment system of the underground water-sealed cavern construction roadway and monitoring well, and the drainage system of the oil production shaft.

[0133] Monitoring groundwater quality data, acquiring groundwater in the reservoir area and conducting groundwater quality analysis, which includes physical analysis, chemical analysis and bacterial analysis, to obtain groundwater quality data;

[0134] The data of the water curtain water supply system is monitored, including water curtain water level data, which is monitored by installing a piezometer in the monitoring well.

[0135] Preferably, in step S104 above, based on the second hydrological monitoring data, the third hydrological monitoring data, and the water curtain water supply system data, and based on a 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] 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, the dynamic risk level of surrounding rock fissure water pressure is determined.

[0137] Based on the natural groundwater level data in the third hydrological monitoring data and the pre-established natural groundwater level evaluation system, the dynamic risk level of the natural groundwater level is determined.

[0138] Based on the hydraulic balance data in the third hydrological monitoring data and the pre-established hydraulic balance evaluation system, the dynamic risk level of hydraulic balance is determined.

[0139] Based on the groundwater quality data in the third hydrological monitoring data and the pre-established groundwater quality assessment system, the dynamic risk level of groundwater quality is determined.

[0140] Based on the water level data in the water curtain water supply system and the pre-established water curtain water level evaluation system, the dynamic risk level of the water curtain water level is determined.

[0141] The overall risk level of the cavern is obtained by weighting and comprehensively processing the dynamic risk levels of surrounding rock fissure water pressure, natural groundwater level, hydraulic balance, groundwater quality, and water curtain level.

[0142] Preferably, 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, the dynamic risk level of the surrounding rock fissure water pressure is determined, including:

[0143] The surrounding rock fissure water pressure is obtained by monitoring the piezometer installed in the pressure gauge hole. The water potential change is determined based on the surrounding rock fissure water pressure. The correlation between slurry spread and seepage in the underground water-sealed cavern is analyzed based on the water potential change. Based on the correlation between slurry spread and seepage in the underground water-sealed cavern, an evaluation system for surrounding rock fissure water pressure is established.

[0144] The establishment of a surrounding rock fissure water pressure evaluation system includes: establishing the relationship between the surrounding rock fissure water pressure monitored by the piezometer and the pressure during the pressure stabilization stage of the airtightness test, as well as the proportion of the number of times the head loss quantitative index (FLF) of the surrounding rock fissure water pressure monitored by the piezometer tends to a specified value, and establishing the correspondence between the above relationship, the above proportion 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 For the water head of the water curtain tunnel, H c Hs is the hydraulic head of the surrounding rock fissure water pressure calculated based on piezometer readings; Hs is the hydraulic head of the vault 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 installed in the pressure gauge hole to monitor the water pressure in the surrounding rock fissures before operation. By calculating the changes in water potential, a semi-quantitative analysis of the correlation between the spread of slurry and seepage in the underground water-sealed cavern is carried out. Figure 5This is a structural example diagram for monitoring fissure water pressure in surrounding rock. The arch shape in the diagram represents a cavern, and the piezometer is installed in the pressure gauge orifice. Other parameters are already shown. Figure 5 The bid was successful.

[0147] If there is blockage around the water curtain system, the water curtain system will not adequately replenish the surrounding rock fissures. The water pressure in the surrounding rock fissures between the water curtain system and the cavern will initially decrease sharply and then stabilize. c As Hs approaches, FLF approaches 1. Figure 6 This diagram illustrates an example of blockage around a water curtain system. w For the water head of the water curtain tunnel, H w The nearby shaded area is a blockage around the water curtain system.

[0148] If there is blockage around the cavern, the fissure water supply around the cavern will be insufficient. The fissure water pressure in the surrounding rock between the water curtain system and the oil storage cavern will initially remain stable, but will then begin to drop sharply near the oil storage cavern. c As Hw approaches, FLF approaches 0. Figure 7 This is an example diagram showing a blockage around a cavern. The shaded area around the cavern represents the blockage area.

[0149] During operation, when the pressure count in the pressure gauge orifice is less than the surrounding rock fissure water pressure during the pressure stabilization phase of the airtightness test, the dynamic risk level of the surrounding rock fissure water pressure is marked.

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

[0151] Natural groundwater level data were obtained by monitoring the piezometer installed in the pressure gauge hole, and a natural groundwater level evaluation system was established based on the natural groundwater level data.

[0152] Establishing a natural groundwater level evaluation system includes: establishing the primary high-low relationship between the natural groundwater level obtained from piezometer monitoring and the design groundwater level, as well as establishing the correspondence between the above primary high-low relationship, signs of leakage 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 H l The natural groundwater level is the head value calculated based on piezometer readings, P. c Piezometer reading, H0—Piercing height of the piezometer, H d To design the groundwater level.

[0154] Natural groundwater levels include surface hydrological monitoring well water levels and vertical well water levels. The natural groundwater level in a reservoir area is affected by factors such as rainfall, atmospheric pressure, water potential, and reservoir boundary conditions. Surface hydrological monitoring aims to check the hydrogeological environment required for sealing stored goods in underground storage facilities; if the overall water environment changes, it may affect the foundation of the water seal design.

[0155] The water level in surface hydrological monitoring wells is automatically monitored by installing piezometers inside the wells, and the water level in vertical wells is automatically monitored by installing piezometers in the vertical wells. In this embodiment, the piezometers are installed 10m-20m above the sealing plug of the vertical well, with a measurement accuracy of ±0.1%. The water levels in the surface hydrological monitoring wells and the vertical wells 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 the actual situation.

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

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

[0158] Obtain the cavern's drainage volume, inflow volume, and water replenishment volume of the water curtain system. Use the cavern's drainage volume and water replenishment volume of the water curtain system as hydraulic balance data. Evaluate the hydraulic balance status of the cavern based on the hydraulic balance data and establish a hydraulic balance evaluation system.

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

[0160] In this embodiment, automatic monitoring of hydraulic balance is set up 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 assess the hydraulic balance status of the reservoir area.

[0161] Groundwater-sealed cavern projects typically have flow meters installed in the water supply systems of the construction tunnels and monitoring wells, as well as the drainage systems of the oil production shafts. The water supply systems of the construction tunnels and monitoring wells replenish groundwater into the water curtain tunnels, while the drainage systems of the oil production shafts pump out the inflow of water into the cavern to maintain its daily operation.

[0162] By regularly collecting data on the water supply and inflow of the water curtain system, the hydraulic balance of the cave is evaluated. Based on the collected data on water supply and inflow, combined with local average annual rainfall information, the average annual hydraulic fluctuations of the cave are determined, providing a basis for the daily maintenance of the cave.

[0163] In this embodiment, the total water replenishment of the construction roadway water replenishment system and the total drainage of the oil well are monitored once a day. The load of the drainage equipment should be closely monitored. When the drainage equipment cannot guarantee timely drainage of the gushing water, it should be replaced with a water pump with a larger drainage capacity or an additional water pump should be provided. At the same time, the dynamic risk level of hydraulic balance should be marked.

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

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

[0166] Establishing a groundwater quality assessment system includes: obtaining the physical, chemical, and bacterial indicators of groundwater and comparing them with the corresponding indicators in the water quality monitoring report before the cavern's operation; and establishing the correspondence between the above-mentioned similarity, changes in the color and odor of the water body, and the dynamic risk level of groundwater quality.

[0167] During operation, groundwater quality in the reservoir area is monitored regularly. Groundwater analysis includes physical, chemical, and bacterial analyses. By analyzing water quality, the impact of the stored products on the surrounding rock and groundwater is examined, ensuring the protection of groundwater resources and compliance with environmental protection requirements. Water quality monitoring aims to ensure that the groundwater quality throughout the reservoir area meets the requirements of being similar to and compatible with the original water quality in the reservoir area. The parameters from the water quality monitoring are also used for hydrogeological analysis and corrosivity assessment.

[0168] Water quality monitoring in underground water-sealed caverns differs from that in wastewater treatment. The evaluation is based on the undisturbed natural water quality before construction, and mainly analyzes the unstable factors affecting the stability of the cavern and the water-sealed environment.

[0169] In this embodiment, physical analysis of groundwater quality is used to determine physical indicators affecting the stability of the cavern and the water-sealing environment, such as:

[0170] (1) Analyze the conductivity and temperature of groundwater, as these physical indicators 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 silt and dust. If the suspended matter exceeds the standard, it will cause the surrounding rock fissures to be blocked and the water seal environment to be destroyed.

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

[0173] Chemical analysis of groundwater was used to identify chemical indicators affecting cavern stability and the water-sealed environment, such as:

[0174] (1) Analyze whether the anions and cations in the groundwater are in balance. Anion and cation balance analysis is used to evaluate water quality and test quality. If the anions and cations are out of balance, the water quality test items should be checked, which may be due to the large measurement error of some ions.

[0175] (2) Analyze COD. COD, or chemical oxygen demand, reflects the degree of groundwater pollution by reducing substances. This indicator 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] Bacterial analysis of groundwater was used to identify bacterial indicators that affect cavern stability and the water-sealed environment, such as:

[0179] (1) Analyze the total amount of aerobic and anaerobic bacteria. Aerobic and anaerobic bacteria will corrode steel structures and pollute the groundwater environment.

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

[0181] (3) Analyze the content of slime-forming bacteria. Slime-forming bacteria grow and reproduce the fastest. They easily synthesize capsules and slime layers on the surface of fissures, which block joint fissures and destroy the water seal environment.

[0182] In addition to the bacterial indicators mentioned above, 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 includes dissolved gas molecules to identify dissolved gas indicators that affect cavern stability and the water seal environment, such as:

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

[0185] (2) Analyze the CO2 and O2 content in groundwater. The reproduction and death of bacteria and aquatic organisms in the water will cause changes in the CO2 and O2 content in the water. When the free CO2 content in the 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 a type of reducing bacteria. When the water contains abundant sulfate and organic matter, the reducing bacteria can reduce sulfate and decompose organic proteins to produce a large amount of hydrogen sulfide. This is especially likely to occur when the water body is hypoxic, thus polluting the groundwater environment.

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

[0188] In this embodiment, the groundwater quality monitoring and evaluation of the reservoir area should refer to the water quality testing reports from the early stages of construction or operation, analyze the relative content ratios of various indicators, and simultaneously meet local groundwater standards and environmental protection requirements, for example:

[0189] In terms of physical indicators, the total suspended solids are less than 10 mg / L;

[0190] In terms of chemical indicators, the content of hydrocarbons is less than 10 ppm; the pH is between 6.5 and 8.5.

[0191] Among the bacterial indicators, the total number of aerobic bacteria was less than 1000 CFU / ml; the total number of anaerobic bacteria was less than 1000 CFU / ml; the content of sulfate-reducing bacteria was 0 CFU / ml; and the content of mucus-forming bacteria was 0 CFU / 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, based on the water curtain level data in the water curtain supply system data and the pre-established water curtain level evaluation system, the dynamic risk level of the water curtain level is determined, including:

[0194] The water level data of the water curtain is obtained by the piezometer installed in the pressure gauge hole, and a water curtain water level evaluation system is established based on the water curtain water level data;

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

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

[0197] The water level in the water curtain tunnel should be kept constant by controlling the water replenishment mechanism within the construction tunnel. The water level in the water curtain tunnel should be automatically monitored by installing piezometers in monitoring wells. In this embodiment, the piezometers are installed 5-10 meters above the roof of the water curtain tunnel, with a measurement accuracy of ±0.1%. The water level in the water curtain tunnel should conform to the formula H = P. c ×100+H0≥H d The requirement is that H is the head value of the water level in the water curtain tunnel calculated based on the piezometer reading, and the water level in the water curtain tunnel is taken as the water curtain level. The installation height and measurement accuracy of the piezometer can be adjusted according to the actual situation.

[0198] The water curtain water supply system and monitoring well water level measurement device have automatic start and stop water supply functions, and also provide manual control functions, allowing for manual water supply in special circumstances. The device transmits water level monitoring signals to the integrated control room, which then operates the water supply start action. The water supply start action can be automatic or manual, both operated by the integrated control room.

[0199] If the groundwater level in the monitoring well is lower than the designed water curtain level during operation, the water curtain water supply system should be activated to replenish water to the construction roadway. At the same time, the groundwater environment in the reservoir area and surrounding areas should be checked for signs of oil and gas leaks. The cause of the drop in the water curtain roadway should be identified, corrective measures should be taken, and the dynamic risk level of the water curtain level should be marked.

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

[0201] Based on real-time monitoring data from the second and third hydrological monitoring systems and the water curtain supply system, dynamic risk classification and early warning can be achieved, providing direct evidence for the safety assessment and risk decision-making of underground water-sealed caverns.

[0202] The comprehensive safety evaluation table for the entire life cycle of underground water-sealed caverns is detailed in Table 4. According to Table 4, the dynamic risk level of various data can be located in a timely manner throughout the entire life cycle of cavern operation, and the causes can be analyzed in a targeted manner. Corresponding measures can be taken to correct the risks 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 indicator. The risk level classification of the entire underground water-sealed cavern reservoir area is as follows:

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

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

[0210] A total score of 40-60 indicates that the entire reservoir area is in a medium-risk state;

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

[0212] Both local and overall risks should be analyzed specifically to identify their causes, and corrective measures should be taken to ensure the safe operation of the cavern.

[0213] The evaluation content, proportion allocation, evaluation criteria and scores, rating, and local risk level in Table 4 above can be adjusted appropriately according to the actual construction situation.

[0214] In this embodiment, during operation, when the pressure count value in the pressure gauge orifice is less than the surrounding rock fissure water pressure during the pressure stabilization phase of the airtightness test, the dynamic risk level of the surrounding rock fissure water pressure is marked. The measures typically taken for this dynamic risk level include:

[0215] ① Conduct water quality analysis on the groundwater in the monitoring well to determine if there is a large amount of bacteria that may be causing blockage of joints and fissures. If so, carry out appropriate sterilization treatment and conduct water quality analysis on the water curtain supply and surface water quality monitoring wells.

[0216] ② Check whether the elevation of the surrounding hydrogeological monitoring boreholes, monitoring wells and other hydrogeological boreholes is higher than the design groundwater level and the design water curtain level.

[0217] When the water level of the surrounding hydrogeological monitoring boreholes and wells is higher than the design groundwater level, the integrity of the water curtain system and the quality of the water supply should be checked, and oil and gas leak detection should be carried out in the piezometer area and the nearby surface. If any problems are found, they should be dealt with immediately, and the groundwater level around the piezometer should be restored.

[0218] When the water level of the surrounding hydrogeological monitoring boreholes and wells is lower than the design groundwater level or the design water curtain level, the water curtain water supply system should be activated in a timely manner to replenish water and restore the groundwater level to above the design 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 design groundwater level, an oil and gas leak test should be performed on the shaft's sealing plug. If a problem is found, it should be dealt with immediately. At the same time, the shaft should be manually injected with water to restore the groundwater level to above the design groundwater level.

[0221] In this embodiment, during operation, when the water level in a hydrogeological monitoring well or a vertical shaft is lower than the designed groundwater level, signs of oil and gas leaks in the surrounding area are checked, and the dynamic risk level of the natural groundwater level is marked. The measures typically taken for this dynamic risk level include:

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

[0223] ② Check whether the water level of the surrounding hydrogeological monitoring boreholes and monitoring wells is higher than the design groundwater level and the design water curtain level.

[0224] When the water level of the surrounding hydrogeological monitoring boreholes and wells is higher than the design groundwater level, the integrity of the water curtain system and the water quality of the borehole should be checked, and oil and gas leak detection should be carried out on the borehole and the nearby surface. If any problems are found, they should be dealt with immediately, and the groundwater level of the borehole and the surrounding area should be restored.

[0225] When the water level in the surrounding hydrogeological monitoring wells is lower than the designed groundwater level, the water curtain water supply system should be activated in a timely manner to replenish the 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 design groundwater level, conduct oil and gas leak detection on the shafts and surrounding areas. If any problems are found, they should be dealt with immediately. At the same time, the shafts should be manually injected with water to restore the groundwater level to above the design groundwater level.

[0228] If special circumstances arise during operation that prevent the guarantee of the designed groundwater level, emergency measures such as activating the water curtain water supply system and temporary water injection should be taken to restore the water level, or the operating pressure inside the tunnel should be reduced.

[0229] Under any extreme circumstances, the groundwater level should be guaranteed 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 related to the specific indicators. For specific indicators that do not meet the requirements, the following measures are typically taken:

[0231] The proliferation of microorganisms in groundwater environments can lead to a sharp drop in oxygen concentration, the death of aquatic organisms, and changes in CO2 and O2 levels. For example, the proliferation of anaerobic microorganisms, through their anaerobic respiration, produces byproducts that cause groundwater to turn black and smelly. To prevent oxygen depletion and blackening / smelling of the water caused by excessive bacterial growth, O2 should be introduced into the water. The bacteria in the water will then consume organic pollutants and purify the water.

[0232] If the total suspended solids in the water are greater than 10 mg / L, water filtration measures are required.

[0233] If the water contains excessive levels of bacteria and microorganisms, sodium hypochlorite or bactericides should be used for sterilization. Physical and chemical methods, such as adding chemicals into monitoring wells, should be used to treat the water to avoid polluting the surrounding groundwater environment. At the same time, local groundwater standards and environmental protection requirements should be followed.

[0234] Risks arising from other indicators can be mitigated based on the implementation of construction to ensure the safe operation of the cavern; these will not be listed here.

[0235] Based on the same inventive concept, this invention also provides a device for evaluating the safety of underground water-sealed caverns throughout their entire life cycle. This device can be installed in equipment with computer instruction processing capabilities, and its structure is as follows: Figure 8 As shown, package

[0236] Data acquisition module 11 is used to acquire hydrological monitoring information and water curtain system experimental data of the underground water-sealed cavern during the construction period; acquire and analyze hydrological information and surrounding rock fissure water pressure of the underground water-sealed cavern before operation; and acquire geological data of the underground water-sealed cavern throughout its entire life cycle 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 hydrological monitoring information and experimental data of the water curtain system, predict potential risk areas in the future based on the evolution trend of historical data, establish a risk identification and evaluation system for water pressure in surrounding rock fissures, and determine the water seal safety evaluation system and classify the dynamic risk level of the underground water-sealed cavern throughout its entire life cycle based on the real-time monitoring geological data obtained by the data acquisition module.

[0238] Regarding the underground water-sealed cavern full life cycle water seal safety evaluation device in the above embodiments, the specific operation methods of each module have been described in detail in the embodiments of the relevant method, and will not be elaborated here.

[0239] The method and apparatus described in this embodiment predict potential risk areas by monitoring first hydrological monitoring data and water curtain system experimental data during cavern construction; before cavern operation, second hydrological monitoring data is obtained based on airtightness tests of potential risk areas; and during cavern operation, third hydrological monitoring data and water curtain water supply system data are monitored for potential risk areas. Based on data monitoring and analysis throughout the entire lifecycle of the cavern (construction, pre-operation, and operation), and a pre-constructed water seal safety evaluation system, the risk level of the cavern is evaluated. Construction-period data monitoring forms the basis for operational-period data monitoring and evaluation, and operational-period data monitoring is a continuation of construction-period data monitoring. This method effectively integrates various monitoring data throughout the cavern's entire lifecycle, using multiple monitoring data such as natural groundwater level, water curtain level, surrounding rock fissure water pressure, hydraulic balance, and groundwater quality to create a safety risk identification and evaluation system for underground water-sealed caverns. It deeply mines and utilizes various monitoring data, and based on the correlation between data, promptly identifies risks in water-sealed caverns, ensuring the long-term, stable, and safe operation of underground water-sealed caverns. This method addresses the discontinuity and limitations of existing water seal monitoring methods used in underground caverns. Furthermore, it allows for adjustments to parameter settings, evaluation criteria, and scores based on actual working conditions, enabling fine-tuning of risk levels. This proposed method has significant application value for various underground engineering and underground space projects, including underground water-sealed caverns.

[0240] This invention also provides a computer storage medium storing computer-executable instructions, which, when executed by a processor, enable a method for evaluating the safety of water-sealed underground water-sealed caverns throughout their entire life cycle.

[0241] This 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, it implements a method for evaluating the safety of water seals throughout the entire life cycle of underground water-sealed caverns.

[0242] Unless otherwise specifically stated, terms such as processing, calculation, operation, determination, display, etc., may refer to the actions and / or processes of one or more processing or computing systems or similar devices that represent the manipulation and conversion of data representing physical (e.g., electronic) quantities within the registers or memory of the processing system into other data similarly representing physical quantities within the memory, registers, or other such information storage, transmission, or display devices of the processing system. Information and signals can 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 can be represented by voltage, current, 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 may be rearranged without departing from the scope of this disclosure. The appended method claims provide elements of various steps in an exemplary order and are not intended to limit the scope to the specific order or hierarchy described.

[0244] In the detailed description above, various features are combined together in a single embodiment to simplify this disclosure. This approach to disclosure should not be construed as reflecting an intention that embodiments of the claimed subject matter require more features than are explicitly stated in each claim. Rather, as reflected in the appended claims, the invention is presented with fewer features than all of the features in a single disclosed embodiment. Therefore, the appended claims are hereby explicitly incorporated into the detailed description, with each claim representing a separate preferred embodiment of the invention.

[0245] Those skilled in the art will also understand that the various illustrative logic blocks, modules, circuits, and algorithm steps described in conjunction with the embodiments herein can be implemented as electronic hardware, computer software, or a combination thereof. To clearly illustrate the interchangeability between hardware and software, the various illustrative components, blocks, modules, circuits, and steps described above are generally described in terms of their functionality. Whether such functionality is implemented as hardware or software depends on the specific application and the design constraints imposed on the overall system. Those skilled in the art can implement the described functionality in alternative ways for each specific application; however, such implementation decisions should not be construed as departing from the scope of this disclosure.

[0246] The steps of the methods or algorithms described in conjunction with the embodiments herein can be directly embodied in hardware, software modules executed by a processor, or a combination thereof. The software modules can reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disks, removable disks, CD-ROMs, or any other form of storage medium well known in the art. An exemplary storage medium is connected to the processor, enabling the processor to read information from and write information to the storage medium. Of course, the storage medium can also be a component of the processor. The processor and storage medium can reside in an ASIC. The ASIC can reside in a user terminal. Alternatively, the processor and storage medium can exist as discrete components in the user terminal.

[0247] For software implementation, the techniques described in this application can be implemented using modules (e.g., procedures, functions, etc.) that perform the functions described in this application. This software code can be stored in memory units and executed by a processor. The memory units can be implemented within the processor or outside the processor; in the latter case, they are communicatively coupled to the processor via various means, as is well known in the art.

[0248] The foregoing description includes examples of one or more embodiments. It is certainly impossible to describe all possible combinations of components or methods in order to describe the above embodiments, but those skilled in the art will recognize that further combinations and arrangements of the various embodiments are possible. Therefore, the embodiments described herein are intended to cover all such changes, modifications, and variations that fall within the scope of the appended claims. Furthermore, the term "comprising" as used in the specification or claims is interpreted in a manner similar to the term "including," as interpreted when used as a conjunction in the claims. Additionally, the use of any term "or" in the specification of the claims is intended to mean "non-exclusive or."

Claims

1. A method for evaluating the safety of water seals throughout the entire life cycle of underground water-sealed caverns, characterized in that, include: During the construction of the cavern, first hydrological monitoring data and water curtain system experimental data are acquired, the data evolution trend and data distribution range 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 trend and data distribution range. Before the operation of the cavern, based on the airtightness test of the potential risk area, the second hydrological monitoring data before the operation of the cavern is obtained and analyzed. The second hydrological monitoring data includes the water pressure in the surrounding rock fissures. During the operation of the cavern, third-party hydrological monitoring data and water curtain water supply system data are monitored for potential risk areas; the third-party hydrological monitoring data includes natural groundwater level data, hydraulic balance data, and groundwater quality data; Based on the second and third hydrological monitoring data and the water curtain supply system data, and using a pre-constructed water seal safety evaluation system, the local dynamic risk levels of different risk indicators in the potential risk area are determined. Based on these local dynamic risk levels, the overall risk level of the cavern is then determined, specifically including: 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, the dynamic risk level of surrounding rock fissure water pressure is determined. Based on the natural groundwater level data in the third hydrological monitoring data and the pre-established natural groundwater level evaluation system, the dynamic risk level of the natural groundwater level is determined. Based on the hydraulic balance data in the third hydrological monitoring data and the pre-established hydraulic balance evaluation system, the dynamic risk level of hydraulic balance is determined. Based on the groundwater quality data in the third hydrological monitoring data and the pre-established groundwater quality assessment system, the dynamic risk level of groundwater quality is determined. Based on the water level data in the water curtain water supply system and the pre-established water curtain water level evaluation system, the dynamic risk level of the water curtain water level is determined. The overall risk level of the cavern is obtained by weighting and comprehensively processing the dynamic risk levels of surrounding rock fissure water pressure, natural groundwater level, hydraulic balance, groundwater quality, and water curtain level.

2. The method as described in claim 1, characterized in that, The acquisition of the first hydrological monitoring data and the water curtain system experimental data includes: Collect primary hydrological monitoring data and experimental data from the water curtain system; The first hydrological monitoring data includes at least one of the following: groundwater level and water quality data, atmospheric pressure and precipitation data, pore water pressure data, seepage points and seepage point characteristics data in the tunnel, and construction water consumption and drainage data. The experimental data of the water curtain system includes at least one of the following: water supply data of the water curtain tunnel and water curtain orifice, and water injection quality data of the water curtain orifice. The water curtain system experiment includes at least one of the following: single-hole pressure water test, effectiveness test, and comprehensive hydraulic test.

3. The method as described in claim 1, characterized in that, The process of obtaining and analyzing second-stage hydrological monitoring data before the operation of the cavern, based on airtightness tests of potential risk areas, includes: An airtightness test was conducted on the potential risk area, and second hydrological monitoring data was collected during the airtightness test. The second hydrological monitoring data included groundwater level data and pressure data; the pressure data included the surrounding rock fissure water pressure. The groundwater level and pressure data were analyzed.

4. The method as described in claim 1, characterized in that, Also includes: Before conducting an airtightness test on a potentially risky area, determine whether the following test conditions are met. If so, then proceed with the airtightness test: The underground cavern has been completed and passed inspection. The installation and commissioning of the vertical shaft have been completed and passed inspection. The cave tanks inside the cave have been calibrated; The groundwater level and pressure monitoring system has been installed, debugged, and is now recording data.

5. The method as described in claim 4, characterized in that, The airtightness test includes a preparation stage, an air injection and pressurization stage, a pressure stabilization stage, and a detection and judgment stage. During the preparation phase, water is injected into the construction tunnel, water curtain tunnel and vertical shaft. Instruments with measurement range and accuracy technical requirements that meet the needs of airtightness test analysis and judgment are prepared and debugged. Monitoring instruments are started. The monitoring instruments include at least one of the following: groundwater level, water pressure, initial temperature inside the tunnel, and liquid level inside the tunnel. During the gas injection and pressurization stage, test gas is injected into the test chamber at a preset gas pressurization rate, and the temperature and pressure of the injected gas are controlled. The monitoring index data of the chamber are measured and recorded at a preset frequency. During the pressure stabilization phase, the difference between the gas pressure inside the cavern and the preset test pressure is controlled to be no greater than a set pressure threshold. If the difference is greater than the set pressure threshold, the gas pressure inside the cavern is adjusted by injecting gas, and the monitoring index data of the cavern are measured and recorded at a preset frequency. During the detection and judgment phase, the monitoring index data of the cavern are measured and recorded at a preset frequency. Based on the temperature change data inside 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 of the test gas pressure inside the cavern are determined. The real-time change data at different times are compared with the initial pressure data of this phase. If the change is not greater than the preset allowable change, the airtightness of the cavern is determined to be qualified.

6. The method as described in claim 1, characterized in that, The determination of 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 includes: The surrounding rock fissure water pressure is obtained by monitoring the piezometer installed in the pressure gauge hole. The water potential change is determined based on the surrounding rock fissure water pressure. The correlation between the slurry spread and seepage in the underground water-sealed cavern is analyzed based on the water potential change. Based on the correlation between the slurry spread and seepage in the underground water-sealed cavern, an evaluation system for the surrounding rock fissure water pressure is established. The establishment of the surrounding rock fissure water pressure evaluation system includes: establishing the relationship between the surrounding rock fissure water pressure monitored by the piezometer and the pressure during the pressure stabilization stage of the airtightness test, as well as the proportion of the number of times the head loss quantitative index FLF of the surrounding rock fissure water pressure monitored by the piezometer tends to a specified value, and establishing the correspondence between the magnitude relationship, the proportion of the number 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 For the water head of the water curtain tunnel, H c H is the hydraulic head calculated based on piezometer readings of the surrounding rock fissure water pressure; s The water head at the vault of the oil storage cavern.

7. The method as described in claim 4, characterized in that, The determination of the dynamic risk level of natural groundwater level based on natural groundwater level data from the third hydrological monitoring data and a pre-established natural groundwater level evaluation system includes: Natural groundwater level data are obtained by monitoring the piezometer installed in the pressure gauge hole, and a natural groundwater level evaluation system is established based on the natural groundwater level data. The establishment of the natural groundwater level evaluation system includes: establishing the first high-low relationship between the natural groundwater level obtained by the piezometer monitoring and the design groundwater level, and establishing the correspondence 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 conforms to the following formula: H l =P c ×100+H0≥H d H l The natural groundwater level is the head value calculated based on piezometer readings, P. c Piezometer reading, H0—Piercing height of the piezometer, H d To design the groundwater level.

8. The method as described in claim 1, characterized in that, The determination of the dynamic risk level of hydraulic balance based on the hydraulic balance data in the third hydrological monitoring data and the pre-established hydraulic balance evaluation system includes: Obtain the cavern's drainage volume, inflow volume, and water replenishment volume of the water curtain system. Use the cavern's drainage volume and water replenishment volume of the water curtain system as hydraulic balance data. Evaluate the hydraulic balance status 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 correspondence between the excess proportion of the cavern's drainage volume, the excess proportion of the water curtain system's replenishment volume, and the excess proportion of the cavern's inflow volume and the dynamic risk level of the hydraulic balance.

9. The method as described in claim 1, characterized in that, Based on groundwater quality data from the third hydrological monitoring data and a pre-established groundwater quality assessment system, the dynamic risk level of groundwater quality 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 physical, chemical, and bacterial indicators of groundwater and their similarity to the corresponding indicators in the water quality monitoring report before the operation of the cavern, and establishing the correspondence between the similarity, the changes in the color and odor of the water body, and the dynamic risk level of groundwater quality.

10. The method as described in claim 1, characterized in that, Based on the water curtain level data from the water curtain supply system and the pre-established water curtain level evaluation system, the dynamic risk level of the water curtain level is determined, including: The water level data of the water curtain is obtained by monitoring the piezometer installed in the pressure gauge hole, and a water curtain water level evaluation system is established based on the water curtain water level data; The establishment of the water curtain level evaluation system includes: establishing a second high-low relationship between the water curtain level height monitored by the piezometer and the designed water curtain level height, and establishing the correspondence between the second high-low relationship, the change of water pressure in the surrounding rock fissures, the leakage signs of surrounding oil and gas, and the dynamic risk level of the water curtain level.

11. A device for evaluating the safety of water-sealed underground caverns throughout their entire life cycle, characterized in that, include: The data acquisition module is used to acquire the first hydrological monitoring data and water curtain system experimental data during the construction period; Acquire and analyze the second hydrological monitoring data before operation; monitor the third hydrological monitoring data and water curtain water supply system data in potential risk areas during operation; The water seal safety evaluation module is used to analyze the data evolution trend and data distribution range of the first hydrological monitoring data and the water curtain system experimental data, and predict potential risk areas based on the data evolution trend and data distribution range; And based on the second hydrological monitoring data, the third hydrological monitoring data, and the water curtain water supply system data, and based on a 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, specifically for: 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, the dynamic risk level of surrounding rock fissure water pressure is determined. Based on the natural groundwater level data in the third hydrological monitoring data and the pre-established natural groundwater level evaluation system, the dynamic risk level of the natural groundwater level is determined. Based on the hydraulic balance data in the third hydrological monitoring data and the pre-established hydraulic balance evaluation system, the dynamic risk level of hydraulic balance is determined. Based on the groundwater quality data in the third hydrological monitoring data and the pre-established groundwater quality assessment system, the dynamic risk level of groundwater quality is determined. Based on the water level data in the water curtain water supply system and the pre-established water curtain water level evaluation system, the dynamic risk level of the water curtain water level is determined. The overall risk level of the cavern is obtained by weighting and comprehensively processing the dynamic risk levels of surrounding rock fissure water pressure, natural groundwater level, hydraulic balance, groundwater quality, and water curtain level.

12. A computer storage medium, characterized in that, The computer storage medium stores computer-executable instructions, which, when executed by a processor, implement the full life-cycle water seal safety evaluation method for underground water-sealed caverns as described in any one of claims 1-10.

13. 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 full life-cycle water seal safety evaluation method for underground water-sealed caverns as described in any one of claims 1-10.

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