Underground water seal oil depot water seal performance evaluation method and system considering blasting vibration

Abstract

The invention provides an underground water seal oil depot water seal performance evaluation method and system considering blasting vibration, and the method comprises the steps: forming a model without blast holes in each excavation segment of a single footage based on blasting parameters and geological material parameters, and calculating blasting vibration simulation data through a solver; utilizing a post-processing system to extract a displacement time-history curve and a displacement boundary condition acting on the contour surface of the surrounding rock, and applying a simulated blasting load to the contour surface of the cavern to determine damage parameters of the surrounding rock; performing damage permeability measurement based on the surrounding rock sample, and determining rock sample damage variables by combining a dynamic impact test to form a damaged surrounding rock permeability coefficient relation table; and constructing a hydrogeological model of the surrounding rock of the underground water seal oil depot based on the hydrogeological parameters of the surrounding rock of the target depot area, and giving a permeability coefficient matched with the damage parameter to realize water seal performance evaluation. According to the scheme, the adverse effects of the integrity reduction and permeability coefficient increase of the surrounding rock of the cavern caused by circular blasting excavation on the water seal performance are fully considered, so that the evaluation result is more accurate and reasonable.

Description

Technical Field

[0001] The present invention relates to the technical field of reliability testing and evaluation, and in particular to a method and system for evaluating water seal performance of an underground water seal oil depot taking blasting vibration into consideration. Background Art

[0002] In the field of oil reserves, underground water-sealed oil depots have gradually become the preferred form of oil reserves in various countries due to their advantages of small footprint, high safety, short construction period, and large reserve volume. Most underground water-sealed oil depots are built in blocky rock areas such as magmatic rocks or metamorphic rocks with stable chemical composition and mainly crystalline rock masses. Unlined high side walls and large-span underground caverns are used as containers for storing oil products. Therefore, the stability of the cavern and the water sealing effect are the basis and key to the construction and safe operation of underground water-sealed oil depots.

[0003] Based on cost control and the constraints of traditional construction methods, drilling and blasting is still the main method for excavating underground water-sealed caverns. Although the energy released by the explosion of explosives can efficiently break the rock mass, it will inevitably disturb the retained rock mass. The excavation section of the underground water-sealed cavern is large, and the method of partial excavation is usually adopted. The construction method is relatively complex. During the reciprocating advancement of each excavation section, the surrounding rock of the cavern is frequently disturbed by the blasting load, the surrounding rock properties continue to deteriorate, and the cumulative damage effect is significant. Existing studies have shown that the cumulative damage of the surrounding rock of the cavern is related to both the single blasting action and the combined action of multiple blasting loads. Cumulative damage is a dynamic evolution process of rock damage under multiple blasting loads. Its internal mechanism and evolution law are very complex, and this process is usually accompanied by changes in the mechanical properties of the rock mass.

[0004] On the other hand, as a brittle material, rock itself has a large number of microcracks and micro-cracks defects. Therefore, under the action of blasting load, the cumulative damage process of the surrounding rock of the underground water-sealed oil depot cavern can be regarded as a process in which new microcracks are constantly generated inside the rock and old microcracks are constantly developing, connecting, and penetrating. This process has largely led to a decrease in the integrity of the cavern surrounding rock and an increase in the permeability coefficient, which in turn has an adverse effect on the stability and water-sealing performance of the cavern.

[0005] At present, there are two main numerical simulation methods for blasting excavation of underground structures. The first is to establish a model with blastholes, and use a suitable constitutive model and state equation to simulate the explosion process of explosives in the hole. The other is to establish a model without blastholes. According to the Saint-Venant principle, the explosion load is equivalent to a triangular load curve that changes with time and is applied to the equivalent action boundary to simulate the explosion process of explosives. However, when using numerical simulation methods to evaluate the water seal performance of underground water-sealed oil depots, the surrounding rock of the cavern is often equivalent to a uniform continuous medium, and the permeable rock mass is homogeneous and isotropic, which cannot consider the adverse effects of the increased permeability caused by the cumulative damage effect of the surrounding rock under cyclic blasting on the water seal performance of the cavern. When using a model with blastholes to calculate the cumulative damage of the surrounding rock of the cavern under cyclic blasting, due to factors such as the small size of the blastholes, the large number of distributions, and the complex distribution positions, it is very easy to cause problems such as modeling and meshing difficulties, which in turn leads to calculation difficulties or even inability to calculate. When the blasting load equivalent method is used to establish a non-blasthole model to calculate the cumulative damage of the surrounding rock, it is necessary to segment the model according to the detonator segments of the millisecond difference blasting. The large number of blasting footages in the excavation of the underground water-sealed oil depot caverns, the complex distribution of excavation segments under each footage, and the detonator segments in each excavation segment will also lead to problems such as difficulty in modeling and meshing, reducing the calculation efficiency.

[0006] The information disclosed in the background technology section of the present invention is only intended to deepen the understanding of the general background technology of the present invention, and should not be regarded as acknowledging or suggesting in any form that the information constitutes the prior art known to those skilled in the art. Summary of the invention

[0007] To solve the above problem, the present invention provides a method. In one embodiment, the method includes:

[0008] Blasting vibration simulation steps: Calculate the equivalent blasting load curve based on the construction parameters of the blasting plan, and form the corresponding non-blasthole model of each excavation section of the single footage in combination with the material parameters of the reservoir area geology. Calculate the blasting vibration simulation data of each excavation section through the solver;

[0009] Action displacement analysis step: based on the blasting vibration simulation data, using a post-processing system to extract the displacement time history curve of each excavation segment acting on the surrounding rock contour surface, and determine the displacement boundary conditions corresponding to each excavation segment;

[0010] Damage distribution determination steps: applying corresponding boundary conditions on the cavern contour surface to simulate blasting loads, and obtaining the damage variables of the surrounding rock at different positions around the underground water-sealed oil depot cavern under different working conditions under multi-footage cyclic blasting with different blasting schemes;

[0011] The surrounding rock sample preparation steps are as follows: drilling a hole in the formation range of the underground water-sealed oil depot to obtain a core section and processing it to form a surrounding rock sample that meets the set standards;

[0012] Damage permeability measurement steps: Based on the surrounding rock samples, physical and mechanical parameters are obtained through various types of tests, and the rock sample damage variables after the wave velocity test are determined in combination with the dynamic impact test. Based on the rock samples with different degrees of damage, the corresponding permeability coefficients are determined through tests, and the damaged surrounding rock permeability coefficient relationship table is recorded;

[0013] The hydrogeological model establishment step: determining the hydrogeological parameters of the surrounding rock of the target underground water-sealed oil reservoir based on the on-site geological data of the target reservoir area, and constructing the surrounding rock hydrogeological model of the current underground water-sealed oil reservoir according to the hydrogeological parameters;

[0014] Water seal performance evaluation step: determine the corresponding damage variable according to the current blasting plan and working conditions of the surrounding rock, assign a permeability coefficient matching the damage variable to the surrounding rock hydrogeological model, and determine the water seal performance evaluation result of the underground water seal oil depot based on the surrounding rock hydrogeological model after the permeability coefficient is assigned.

[0015] Preferably, in one embodiment, the blasting vibration simulation step includes: collecting and organizing the excavation and blasting plans of the underground water-sealed oil depot caverns, determining the construction parameters of each excavation and blasting plan, including the distribution of blastholes in each excavation section, charging radius and length, explosive density and detonation velocity, and the delay of each detonator section and single-section charging information when using millisecond differential blasting.

[0016] Furthermore, in one embodiment, in the displacement analysis step, the shape and peak characteristics of the displacement time-history curve of the excavation segment acting on the surrounding rock contour surface are analyzed, and representative nodes of a set scale and their corresponding point sets are selected, and the displacement time-history curve corresponding to the selected representative node is used as the displacement time-history curve of the excavation segment of the blasting scheme acting on the cavern contour surface.

[0017] In a preferred embodiment, in an embodiment, the damage distribution determination step includes the following operations:

[0018] The steps of building the overall model of the surrounding rock are as follows: the overall cavern model is built by combining the physical and mechanical parameters of the surrounding rock and the shape and size data of the underground water-sealed oil depot cavern. The corresponding material equation is used to describe the constitutive relationship of the model and set the parameters of the material equation. In addition, the non-reflecting boundary condition is applied;

[0019] Sequence correction step: determine the excavation sequence of each section of each footage of the cavern, and correct the time coordinates in the displacement time history curve of each representative point in different excavation sections under each footage in the blasting plan according to the excavation sequence;

[0020] Displacement application step: The displacement time history curves at the representative points in different excavation segments under different footages after correction are applied as displacement boundary conditions to the cavern model of the footage of the corresponding excavation segment, as a stage calculation model, and the stage calculation model is updated according to the excavation sequence and the solver until the required excavation footage is met, and the calculation model of the last stage is saved as the target calculation model;

[0021] Damage distribution analysis step: import the solution file of the target calculation model into the post-processing software to obtain the damage variables of the surrounding rock at different positions around the cavern under the blasting conditions corresponding to multiple blasting footage cycles.

[0022] Furthermore, in one embodiment, in the damage permeability measurement step, the physical and mechanical parameters of the surrounding rock sample are obtained by the following operations:

[0023] Determine the physical parameter values ​​of the prepared surrounding rock samples based on wave velocity test and density test;

[0024] The rock mechanical parameters of the prepared surrounding rock specimens were determined based on uniaxial compression test, Brazilian splitting test and triaxial compression test.

[0025] Optionally, in one embodiment, in the damage permeability measurement step, the process of determining the rock sample damage variable after the wave velocity test in combination with the dynamic impact test includes:

[0026] Based on the physical and mechanical parameters, surrounding rock samples whose parameter similarity meets the set requirements are selected as impact test rock samples, different dynamic impact tests are carried out on these rock samples, and the longitudinal wave velocity of the rock samples after impact is measured, and the damage variable data of the impact test rock samples are determined according to the change of the longitudinal wave velocity of the rock samples before and after impact;

[0027] Among them, the test parameters of the dynamic impact test are set according to the damage variables corresponding to multi-footprint cyclic blasting in different blasting schemes.

[0028] In a preferred embodiment, in the water sealing performance evaluation step, based on the surrounding rock hydrogeological model, the surrounding rocks at different positions and at different depths from the cavern contour surface are assigned corresponding permeability coefficients according to their corresponding damage variable values ​​with reference to the damaged surrounding rock permeability coefficient relationship table.

[0029] Based on other aspects of the method described in any one or more of the above embodiments, the present invention further provides a storage medium storing program codes that can implement the method described in any one or more of the above embodiments.

[0030] Based on the application aspects of the method described in any one or more of the above embodiments, the present invention also provides a water seal performance evaluation system for underground water seal oil reservoirs taking into account blasting vibration, and the system executes the method described in any one or more of the above embodiments.

[0031] Compared with the closest prior art, the present invention also has the following beneficial effects:

[0032] The present invention provides a method for evaluating the water seal performance of an underground water seal oil depot taking into account the effect of blasting vibration. The method forms a corresponding single footage and each excavation segment without blasthole models based on blasting construction parameters, and calculates blasting vibration simulation data through a solver; a displacement time history curve acting on the surrounding rock contour surface is extracted by a post-processing system to determine the displacement boundary conditions; a simulated blasting load is applied to the cavern contour surface to calculate the damage parameters of the surrounding rock under different blasting conditions; there is no need to establish a large number of blasthole and explosive models with complex distribution, thus avoiding the difficulties in modeling and meshing, ensuring that the simulation can proceed smoothly, and simulating the blasting load by directly applying boundary conditions on the cavern contour surface, thus avoiding the complex process of cutting the model according to the detonator segment used in each footage and excavation segment in the conventional non-blasthole model, thereby significantly improving the calculation efficiency;

[0033] Then, based on the damaged permeability measurement of the surrounding rock samples, the rock sample damage variables after the wave velocity test are determined in combination with the dynamic impact test to form a damaged surrounding rock permeability coefficient relationship table; based on the hydrogeological parameters of the surrounding rock of the target reservoir area, the surrounding rock hydrogeological model of the current oil storage reservoir is constructed, and the permeability coefficient matching the damage parameters is assigned, based on which the water seal performance evaluation is realized. The adoption of this scheme overcomes the problem of insufficient accuracy of the water seal performance evaluation data of the existing oil storage reservoir technology. For different construction methods of segmented blasting excavation of the cavern, the adverse effects of the reduced integrity of the cavern surrounding rock and the increased permeability coefficient caused by cyclic blasting excavation on the water seal performance are fully considered, and the three-dimensional geological hydrological model is refined based on the permeability coefficient matching the surrounding rock damage distribution parameters corresponding to the blasting scheme, so that the evaluation results are more accurate and reasonable.

[0034] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0036] Figure 1It is a flow chart of a method for evaluating water seal performance of an underground water seal oil reservoir taking into account blasting vibration provided by an embodiment of the present invention;

[0037] Figure 2 It is a schematic diagram of the implementation principle of the water seal performance evaluation of the underground water seal oil reservoir considering blasting vibration provided by an embodiment of the present invention;

[0038] Figure 3 (a) is an example diagram of a pilot tunnel excavation model in the upper layer of the main cavern of an underground water-seal oil depot according to the water-seal performance evaluation method of the underground water-seal oil depot considering blasting vibration provided by an embodiment of the present invention;

[0039] Figure 3 (b) is an example diagram of a model of an underground water-seal oil depot with no blastholes in the upper layer of the main cavern of the underground water-seal oil depot according to the water-seal performance evaluation method of the underground water-seal oil depot considering blasting vibration provided by an embodiment of the present invention;

[0040] Figure 4 It is a schematic diagram of a triangle curve of equivalent blasting loads at each detonator section in blasting excavation of an upper middle guide hole in a water seal performance evaluation method for an underground water seal oil depot considering blasting vibration provided by an embodiment of the present invention;

[0041] Figure 5 (a) Figure 5 (b) Figure 5 (c) are schematic diagrams of cavern models of three excavation depths in a method for evaluating water seal performance of an underground water seal oil depot considering blasting vibration provided by an embodiment of the present invention;

[0042] Figure 6 It is a schematic diagram of a three-dimensional hydrogeological calculation model of an underground water seal oil reservoir in a water seal performance evaluation method of an underground water seal oil reservoir taking into account blasting vibration provided in an embodiment of the present invention;

[0043] Figure 7 It is a structural schematic diagram of a water seal performance evaluation system for an underground water seal oil depot taking blasting vibration into consideration provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0044] The following will describe the implementation methods of the present invention in detail in conjunction with the accompanying drawings and embodiments, so that the implementers of the present invention can fully understand how the present invention applies technical means to solve technical problems and achieve the implementation process of technical effects and implement the present invention specifically according to the above implementation process. It should be noted that as long as there is no conflict, the various embodiments and various features of the embodiments in the present invention can be combined with each other, and the technical solutions formed are all within the protection scope of the present invention.

[0045] Although the flowcharts describe the operations as sequential processes, many of the operations may be performed in parallel, concurrently, or simultaneously. The order of the operations may be rearranged. A process may be terminated when its operations are completed, but may also have additional steps not included in the accompanying drawings. A process may correspond to a method, function, procedure, subroutine, subprogram, etc.

[0046] Computer devices include user devices and network devices. Among them, user devices or clients include but are not limited to computers, smart phones, PDAs, etc.; network devices include but are not limited to a single network server, a server group consisting of multiple network servers, or a cloud composed of a large number of computers or network servers based on cloud computing. Computer devices can be operated alone to implement the present invention, or they can be connected to the network and implement the present invention through interactive operations with other computer devices in the network. The network where the computer device is located includes but is not limited to the Internet, wide area network, metropolitan area network, local area network, VPN network, etc.

[0047] The terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments. Unless the context clearly indicates otherwise, the singular forms "one", "one" and "item" used herein are also intended to include plural numbers. It should also be understood that the terms "include" and / or "comprise" used herein specify the existence of stated features, integers, steps, operations, units and / or components, without excluding the existence or addition of one or more other features, integers, steps, operations, units, components and / or combinations thereof.

[0048] Oil reserves are an important part of national security strategy. Underground water-sealed oil depots have gradually become the preferred form of oil reserves in various countries due to their advantages of small footprint, high safety, short construction period, and large reserves. Underground water-sealed oil depots are mostly built in blocky rock areas such as magmatic rocks or metamorphic rocks with stable chemical composition and mainly crystalline rock masses. Unlined high side walls and large-span underground caverns are used as containers for storing oil products. Therefore, the stability of the cavern and the water sealing effect are the basis and key to the construction and safe operation of underground water-sealed oil depots.

[0049] Based on cost control and the constraints of traditional construction methods, drilling and blasting is still the main method for excavating underground water-sealed caverns. Although the energy released by the explosion of explosives can efficiently break the rock mass, it will inevitably disturb the retained rock mass. The excavation section of the underground water-sealed cavern is large, and the method of partial excavation is usually adopted. The construction method is relatively complex. During the reciprocating advancement of each excavation section, the surrounding rock of the cavern is frequently disturbed by the blasting load, the surrounding rock properties continue to deteriorate, and the cumulative damage effect is significant. Existing studies have shown that the cumulative damage of the surrounding rock of the cavern is related to both the single blasting action and the combined action of multiple blasting loads. Cumulative damage is a dynamic evolution process of rock damage under multiple blasting loads. Its internal mechanism and evolution law are very complex, and this process is usually accompanied by changes in the mechanical properties of the rock mass.

[0050] On the other hand, as a brittle material, rock itself has a large number of microcracks and micro-cracks defects. Therefore, under the action of blasting load, the cumulative damage process of the surrounding rock of the underground water-sealed oil depot cavern can be regarded as a process in which new microcracks are constantly generated inside the rock and old microcracks are constantly developing, connecting, and penetrating. This process has largely led to a decrease in the integrity of the cavern surrounding rock and an increase in the permeability coefficient, which in turn has an adverse effect on the stability and water-sealing performance of the cavern.

[0051] At present, there are two main numerical simulation methods for blasting excavation of underground structures. The first is to establish a model with blastholes and use a suitable constitutive model and state equation to simulate the explosion process of explosives in the hole. The other is to establish a model without blastholes and, according to the Saint-Venant principle, apply the explosion load to a triangular load curve that varies with time on the equivalent action boundary to simulate the explosion process of explosives.

[0052] 1) When using numerical simulation methods to evaluate the water seal performance of underground water-seal oil reservoirs, the surrounding rock of the cavern is often regarded as a uniform continuous medium, and the permeable rock mass is homogeneous and isotropic. It is impossible to consider the adverse effects of increased permeability caused by the cumulative damage effect of the surrounding rock under cyclic blasting on the water seal performance of the cavern.

[0053] 2) When using the blasthole model to calculate the cumulative damage of the cavern surrounding rock under cyclic blasting, due to factors such as the small size of the blastholes, the large number of distribution, and the complex distribution location, it is very easy to cause problems such as modeling and meshing difficulties, which in turn leads to calculation difficulties or even inability to calculate.

[0054] 3) When the blasting load equivalent method is used to establish a non-blasthole model to calculate the cumulative damage of the surrounding rock, the model needs to be segmented according to the detonator segment of the millisecond difference blasting. The large number of blasting footages for excavation of underground water-sealed oil depot caverns, the complex distribution of excavation segments under each footage, and the detonator segment in each excavation segment will also lead to problems such as difficulty in modeling and meshing, reducing the calculation efficiency.

[0055] The excavation of underground water-sealed oil depot caverns is usually carried out by segmented blasting, which has the characteristics of dense blasthole distribution and large blasting footage, resulting in limitations of the above two methods in simulating the excavation process of underground water-sealed oil depot caverns. Moreover, in the process of evaluating underground water-sealed oil depots, the damage to the surrounding rock of the cavern caused by blasting vibration, the increase in permeability coefficient, the impact on the change of groundwater level within the reservoir area and the amount of water inflow in the cavern are rarely considered, and accurate simulation analysis results cannot be obtained.

[0056] In order to solve the above problems, the present invention provides a water seal performance evaluation method for an underground water seal oil depot considering blasting vibration. The method considers the cumulative damage effect factor of the surrounding rock under cyclic blasting vibration, and for the construction method of segmented blasting excavation of the cavern, fully introduces the adverse factors of reduced surrounding rock integrity and increased permeability caused by cyclic blasting, and numerically simulates the damage of the surrounding rock of the cavern of the underground water seal oil depot according to the operating characteristics of the cyclic blasting construction method, including numerical simulation of blasting vibration of each excavation segment under a single footage, extraction of displacement time history curves of each excavation segment acting on the cavern contour surface, and calculation of the damage distribution of the surrounding rock of the cavern, thereby giving the hydrogeological model of the surrounding rock of the cavern of the underground water seal oil depot with permeability parameters matching its damage distribution, so as to realize accurate evaluation of the water seal performance during or after blasting construction.

[0057] Next, the detailed process of the method of the embodiment of the present invention is described in detail based on the accompanying drawings. The steps shown in the flowchart of the accompanying drawings can be executed in a computer system including a set of computer executable instructions. Although the logical order of each step is shown in the flowchart, in some cases, the steps shown or described can be executed in a different order than here.

[0058] Embodiment 1

[0059] Figure 1 The schematic diagram of the process of the water seal performance evaluation method of the underground water seal oil reservoir considering blasting vibration provided by the first embodiment of the present invention is shown. Figure 1 It can be seen that the method includes the following steps.

[0060] Blasting vibration simulation steps: Calculate the equivalent blasting load curve based on the construction parameters of the blasting plan, and form the corresponding non-blasthole model of each excavation section of the single footage in combination with the material parameters of the reservoir area geology. Calculate the blasting vibration simulation data of each excavation section through the solver;

[0061] Action displacement analysis step: based on the blasting vibration simulation data, using a post-processing system to extract the displacement time history curve of each excavation segment acting on the surrounding rock contour surface, and determine the displacement boundary conditions corresponding to each excavation segment;

[0062] Damage distribution determination steps: Apply corresponding boundary conditions on the cavern contour surface to simulate blasting loads, and obtain the damage variables of the surrounding rock at different positions around the underground water-sealed oil depot cavern under different working conditions under multi-footage cyclic blasting with different blasting schemes;

[0063] The surrounding rock sample preparation steps are as follows: drilling a hole in the formation range of the underground water-sealed oil depot to obtain a core section and processing it to form a surrounding rock sample that meets the set standards;

[0064] Damage permeability measurement steps: physical and mechanical parameters are obtained through various types of tests based on surrounding rock samples, and the damage variables of rock samples after wave velocity test are determined in combination with dynamic impact tests. The corresponding permeability coefficients are determined through tests based on rock samples with different degrees of damage, and the damaged surrounding rock permeability coefficient relationship table is recorded. The test parameters of the dynamic impact test are set according to the damage variables corresponding to multi-footage cyclic blasting in different blasting schemes.

[0065] The hydrogeological model establishment step: determining the hydrogeological parameters of the surrounding rock of the target underground water-sealed oil depot based on the on-site geological data of the target reservoir area, and constructing the surrounding rock hydrogeological model of the current underground water-sealed oil depot according to the physical and mechanical parameters;

[0066] Water seal performance evaluation steps: determine the corresponding damage variables according to the current blasting plan and working conditions of the surrounding rock, assign a permeability coefficient matching the damage variables to the surrounding rock hydrogeological model, and evaluate the water seal performance of the underground water seal oil reservoir based on the groundwater level distribution, cavern water inflow and vertical hydraulic gradient data in the reservoir area.

[0067] In a preferred embodiment, in the blasting vibration simulation step, the excavation and blasting plans of the underground water-sealed oil depot caverns are first collected and sorted, and the construction parameters of each excavation and blasting plan are determined, and then the equivalent blasting load curve and the boundary of the equivalent blasting load are calculated according to the construction parameters. The construction parameters include the distribution of blastholes in each excavation segment, the charging radius and length, the density and detonation velocity of explosives, the delay of each detonator segment when using millisecond differential blasting, and the single-segment charging amount information.

[0068] On the other hand, the material parameters of the reservoir area geology are determined based on the physical and mechanical parameters of the reservoir area geological site. In a preferred embodiment, the physical and mechanical parameters of the reservoir area geological site are determined based on the engineering geological data collected in advance at the underground water-sealed oil depot site. The physical and mechanical parameters include the rock elastic modulus, Poisson's ratio and cohesion of the cavern surrounding rock.

[0069] In actual application, in the blasting vibration simulation step, the process of forming a non-blasthole model of each excavation segment of a single footage based on the construction parameters of the blasting plan includes:

[0070] According to the physical and mechanical parameters, the matching material equation is determined to describe the constitutive relationship of the surrounding rock of the underground water-sealed oil depot, and the parameters of the material equation are set to determine the constitutive material parameters of the surrounding rock of the current underground water-sealed oil depot;

[0071] The calculated equivalent blasting load curve matching the construction parameters of the blasting scheme is applied to the corresponding equivalent action boundary to obtain a blasthole-free model of the surrounding rock of the underground water-sealed oil depot corresponding to the blasting scheme.

[0072] In practical application, appropriate material equations are used to describe the constitutive relationship of the cavern surrounding rock for the underground water-sealed oil depot surrounding rock, and the parameters of the material equations are set. According to the calculated boundary of the equivalent blasting load, the equivalent blasting load curve of each excavation segment calculated in the above operation is applied to the corresponding equivalent action boundary, and a non-reflection boundary condition is applied to the model.

[0073] Further, in an optional embodiment, in the blasting vibration simulation step, the blasting vibration simulation data of each excavation segment is calculated according to the following operations:

[0074] After setting the no-blasthole model of the surrounding rock of the underground water-sealed oil depot according to the setting requirements of the LS-DYNA software solver, the no-blasthole model of each segmented blasting excavation is submitted to the LS-DYNA software solver for calculation, and the corresponding solution log file is obtained as the blasting vibration simulation data result corresponding to the current no-blasthole model.

[0075] Take the blasting excavation of the upper middle pilot hole and the upper layer expansion excavation of the main cavern of an underground water-sealed oil depot as an example.

[0076] Figure 3 (a) Figure 3 (b) are the models of the upper middle pilot hole excavation and blasting and the upper expansion without blastholes of the main cavern of an underground water-sealed oil depot. As shown in the figure, the model is 40m long, 9m wide and 50m high. The excavated cavern is the main cavern of the underground water-sealed oil depot, 30m high and 20m wide, and the excavation footage of one blasting is 3m.

[0077] The on-site engineering geological data of the reservoir area were collected and sorted out to determine the physical and mechanical parameters of the surrounding rock of the main cavern of the underground water-sealed oil depot, including the density, elastic modulus, Poisson's ratio, cohesion, compressive and tensile strength of the rock. According to the physical and mechanical properties of the surrounding rock, the HJC constitutive model relationship was selected as the material model.

[0078] According to the blasting plan for the main cavern of the underground water-sealed oil depot, the millisecond differential blasting is used for blasting the upper middle guide hole. According to the detonator segment, there are 12 sections of equivalent blasting load and its corresponding equivalent action boundary.

[0079] The upper excavation adopts millisecond differential blasting, and there are 9 sections of equivalent blasting load and its corresponding equivalent action boundary according to the detonator section.

[0080] Figure 4 The equivalent blasting load triangle curve of each detonator section of the blasting excavation of the upper middle pilot hole of the main cavern has an action delay of 0 milliseconds, and the subsequent nth section blasting load curve delay is 10n milliseconds; the action delay of each section of the upper expansion excavation is the same. The blasting excavation of the upper middle pilot hole of the main cavern and the upper expansion excavation without blastholes are submitted to the LS-DYNA solver for calculation.

[0081] Next, the action displacement analysis step is performed, and the displacement time history curve of each excavation segment acting on the surrounding rock contour surface is extracted by using a post-processing system based on the blasting vibration simulation data, and the displacement boundary conditions corresponding to each excavation segment are determined;

[0082] In actual application, the post-processing software LS-Prepost is used to extract the displacement time-history curves of each excavation segment on the surrounding rock contour surface; specifically, the d3plot file in the solution file of each segmented blasting excavation model is imported into LS-Prepost, and the displacement time-history curves X-displacement, Y-displacement, and Z-displacement of the nodes on the cavern contour surface in the X, Y, and Z directions in each blasting excavation segment model are viewed through the History function.

[0083] Based on this, for the displacement time-history curve of the excavation segment acting on the surrounding rock contour surface, the shape and peak characteristics of the curve are analyzed, and the representative nodes and their corresponding point sets of the set scale are selected. The displacement time-history curve corresponding to the selected representative node is used as the displacement time-history curve of the excavation segment acting on the cavern contour surface of the blasting scheme;

[0084] In actual application, several representative nodes are selected by checking and comparing the shapes and peak characteristics of the displacement time-history curves of each node on the cavern contour surface in each blasting excavation segmented model in the X, Y, and Z directions; if the shapes and peak characteristics of the displacement time-history curves in the X, Y, and Z directions at the representative node should be the same as or very different from those of the surrounding nodes, meeting the set requirements, the representative point and the surrounding points are regarded as a point set, and the representative points are not repeated in the same point set and between different point sets.

[0085] The displacement time-history curves in the X, Y, and Z directions at each representative node are extracted and saved as the displacement time-history curves of each excavation segment acting on the cavern contour surface.

[0086] Taking the blasting excavation of the upper pilot tunnel and the upper excavation of an underground water-sealed oil depot as an example, the displacement time history curves of each excavation segment acting on the cavern contour surface are extracted.

[0087] Use the post-processing software LS-Prepost of LS-DYNA software to import the d3plot files in the solution files of the upper middle pilot tunnel blasting excavation model and the upper expansion excavation model into LS-Prepost respectively, and use the History function to view the displacement time history curves X-displacement, Y-displacement, and Z-displacement of the nodes on the X, Y, and Z directions of the cavern contour surface in the upper middle pilot tunnel blasting excavation model and the upper expansion excavation model.

[0088] The shapes and peak characteristics of the displacement time-history curves in the X, Y, and Z directions of each node on the cavern contour surface in the upper middle pilot tunnel blasting excavation model and the upper expansion excavation model were checked and compared respectively, and 120 representative nodes and their corresponding point sets were selected respectively. The displacement time-history curves in the X, Y, and Z directions at the representative nodes were extracted and saved as the displacement time-history curves of the upper middle pilot tunnel blasting excavation and the upper expansion excavation on the cavern contour surface.

[0089] Furthermore, the damage distribution determination step is performed: the corresponding boundary conditions are applied on the cavern contour surface to simulate the blasting load, and the damage variables of the surrounding rock at different positions around the underground water-sealed oil depot cavern under the action of multi-footage cyclic blasting in different blasting schemes are obtained;

[0090] In an optional embodiment, the damage distribution determining step includes:

[0091] Steps for constructing the overall cavern surrounding rock model: Combine the physical and mechanical parameters of the surrounding rock and the shape and size data of the underground water-sealed oil depot cavern to construct the overall cavern model of the underground water-sealed oil depot under different excavation footages, use the corresponding material equation to describe the constitutive relationship of the model and set the parameters of the material equation, and also apply the non-reflecting boundary condition;

[0092] Sequence correction step: determine the excavation sequence of each section of each footage of the cavern, and correct the time coordinates of each point in the X, Y, and Z directions at each representative point in different excavation sections under each footage in the displacement time history curve of the blasting scheme according to the excavation sequence;

[0093] Displacement application step: The displacement time history curves at the representative points in different excavation segments under different footages after correction are applied as displacement boundary conditions to the cavern model of the footage of the corresponding excavation segment, as a stage calculation model, and the stage calculation model is updated according to the blasting plan, excavation sequence and solver until the required excavation footage is met. This displacement application is ended, and the calculation model of the last stage is saved as the target calculation model;

[0094] Damage distribution analysis step: import the solution file of the target calculation model into the post-processing software, calculate and analyze the damage variables of the cavern surrounding rock under multiple blasting footage cycle blasting corresponding to the required excavation footage requirements.

[0095] In actual application, in an optional embodiment, the damage variables of the surrounding rock of the underground water-sealed oil depot under different working conditions under multi-footage cyclic blasting in different blasting schemes are calculated according to the following logic:

[0096] Step 1: Establish a cavern model under different excavation depths according to the shape and size of the cavern, use appropriate material equations to describe the constitutive relationship of the cavern surrounding rock and set the parameters of the material equations. Apply non-reflecting boundary conditions to the model.

[0097] Step 2: Determine the excavation sequence of each section of each footage of the cavern, and correct the time coordinates of each point in the displacement time history curve in the X, Y, and Z directions at each representative point in each excavation section under each footage.

[0098] Step 3: Apply the displacement time history curves in the X, Y, and Z directions at the representative points in each excavation segment under each footage after correction to the cavern model of the footage where the excavation segment is located through the keyword *BOUNDARY_PRESCRIBED_MOTION_SET as the displacement boundary conditions, and save them as new calculation models respectively.

[0099] Step 4: Submit the calculation model of the first excavation segment in the first footage to the LS-DYNA software for solution and calculation. Use the *STRESS_INITIALIZATION keyword to take the stress state of the cavern surrounding rock after the excavation blasting of the first excavation segment in the first footage as the initial state of the cavern surrounding rock stress when the second segment of the first footage is excavated. Submit the calculation model of the second excavation segment in the first footage to the LS-DYNA software for restart calculation. And so on, until the simulation of all excavation segments in all footages is completed.

[0100] Step 5: Import the d3plot file in the solution file of the last section of excavation and blasting model into the post-processing software LS-Prepost to obtain the damage variables of the surrounding rock at different positions around the cavern under multiple blasting footage cycles.

[0101] Take the blasting excavation of the lower and upper middle pilot tunnels and the upper expansion excavation of the three adjacent excavation advances of the main cavern as an example.

[0102] like Figure 5 As shown in the figure, the main cavern model of the first three footages of the underground water-sealed oil depot excavation is established according to the shape and size of the cavern, and the HJC material equation is used to describe the constitutive relationship of the surrounding rock of the main cavern and set the parameters of the material equation. Non-reflecting boundary conditions are applied to the three models.

[0103] The calculation termination time of the pilot hole blasting excavation model in the upper layer of the first footage is taken as the starting time of the upper layer excavation of the first footage, and the time coordinates of each point in the displacement time history curve in the X, Y and Z directions at each representative point in the upper layer excavation of the first footage are corrected.

[0104] The calculation termination time of the upper excavation model of the first footage is used as the start time of the blasting excavation of the pilot hole in the upper layer of the second footage, and the time coordinates of each point in the displacement time history curve in the X, Y, and Z directions at each representative point in the blasting excavation of the pilot hole in the upper layer of the second footage are corrected. The same is true for the subsequent operations.

[0105] The displacement time history curves in the X, Y and Z directions at each representative point of the blasting excavation of the pilot tunnel in the upper layer of the first footage are applied to the cavern contour surface in the main cavern model of the first footage through the keyword *BOUNDARY_PRESCRIBED_MOTION_SET and saved as a new calculation model.

[0106] Apply the modified displacement time history curves in the X, Y, and Z directions at each representative point of the upper excavation of the first footage to the cavern contour surface of the main cavern model of the first footage through the keyword *BOUNDARY_PRESCRIBED_MOTION_SET and save it as a new calculation model.

[0107] The calculation model of blasting excavation of the upper pilot hole in the first footage is submitted to the LS-DYNA software solver for calculation, and the corresponding solution log file is obtained.

[0108] Use the *STRESS_INITIALIZATION keyword to inherit the stress state of the main cavern surrounding rock after the excavation and blasting of the upper pilot tunnel of the first footage to the main cavern surrounding rock in the first footage upper excavation calculation model as its initial state.

[0109] Submit the d3dump file in the solution file of the first footage upper layer excavation calculation model and the first footage upper layer middle pilot hole blasting excavation calculation model to the LS-DYNA software restart solver for calculation, and obtain the corresponding solution log file.

[0110] Use the *STRESS_INITIALIZATION keyword to inherit the stress state of the main cavern surrounding rock after the first footage upper layer excavation to the main cavern surrounding rock in the second footage upper layer pilot tunnel blasting excavation calculation model as its initial state.

[0111] Submit the d3dump file in the solution file of the second footage upper pilot hole blasting excavation calculation model and the first footage upper excavation calculation model to the LS-DYNA software to restart the solver for calculation and obtain the corresponding solution log file. The subsequent calculation process is analogous until all excavation segment simulations of all footages are completed.

[0112] The d3plot file in the solution file of the upper excavation in the third section of excavation footage is imported into LS-Prepost to obtain the damage variables of the surrounding rock at different positions around the main cavern under the action of cyclic blasting in the three-section footage.

[0113] The surrounding rock sample preparation steps are as follows: drilling a hole in the formation range of the underground water-sealed oil depot to obtain a core section and processing it to form a surrounding rock sample that meets the set standards;

[0114] In an optional embodiment, in the surrounding rock sample preparation step, for an underground water-sealed oil depot with evaluation requirements, a drill core is obtained within the depot area, and a core section whose depth is close to that of the surrounding rock cavern of the underground water-sealed oil depot and meets the set requirements and whose integrity meets the set requirements is selected from the core, and further processed into a standard rock sample;

[0115] In actual application, the rock sample can be finely processed according to the "Standard for Engineering Rock Test Methods" so that the rock sample diameter, rock sample height, flatness error at both ends, maximum deviation perpendicular to the rock sample axis and diameter error position at the rock sample height are within the set standard range.

[0116] Take an underground water-sealed oil depot as an example, the elevation of its main cavern is -60m. Among the cores drilled in the reservoir area, relatively complete core columns with an elevation of -60m were selected, and the rock samples were finely processed according to the "Standard for Engineering Rock Test Methods" to make the rock samples 50mm in diameter and 100mm in height, with a flatness error of no more than 0.02mm at both ends, a maximum deviation perpendicular to the axis of the rock sample of no more than 0.25°, and a diameter error of no more than 0.3mm in height.

[0117] Furthermore, a damaged permeability measurement step is performed, physical and mechanical parameters are obtained through various types of tests based on surrounding rock samples, and the damage variables of rock samples after wave velocity test are determined in combination with dynamic impact tests. The corresponding permeability coefficients are determined through tests based on rock samples with different degrees of damage, and the records are formed into a damaged surrounding rock permeability coefficient relationship table.

[0118] Preferably, in one embodiment, in the damage permeability measurement step, the physical and mechanical parameters of the surrounding rock sample are obtained by the following operations:

[0119] Determine the physical parameter values ​​of the prepared surrounding rock samples based on wave velocity test and density test;

[0120] The rock mechanical parameters of the prepared surrounding rock specimens were determined based on uniaxial compression test, Brazilian splitting test and triaxial compression test.

[0121] The physical parameters include at least the height, diameter, mass, density, and longitudinal wave velocity data of the rock sample; and the mechanical parameters include at least the uniaxial compressive strength and uniaxial tensile strength data of the rock sample.

[0122] Based on the above embodiments, the prepared rock samples are subjected to mechanical measurement of physical parameters, including height, diameter, mass, density, longitudinal wave velocity, uniaxial compressive strength and tensile strength of the rock samples.

[0123] Further, in an optional embodiment, in the damage permeability measurement step, the process of determining the rock sample damage variable after the wave velocity test in combination with the dynamic impact test includes:

[0124] Based on the physical and mechanical parameters, surrounding rock samples whose parameter similarity meets the set requirements are selected as impact test rock samples. Dynamic impact tests with different velocity gradients and different impact times are carried out on these rock samples, and the longitudinal wave velocity of the rock samples after impact is measured. According to the change of the longitudinal wave velocity of the rock samples before and after the impact, the damage variable data of the impact test rock samples are determined.

[0125] In practical applications, by selecting several rock samples with the same or similar physical parameters, dynamic impact tests with different velocity gradients and different impact times are carried out, the longitudinal wave velocity of the rock samples after impact is tested, the longitudinal wave velocity of the rock samples before and after impact is compared, and the damage variables of the rock samples are determined.

[0126] In order to ensure that the damage distribution corresponding to different blasting schemes and different penetration conditions can clearly define the corresponding permeability, in this operation, the test parameters of the dynamic impact test are set according to the damage variables of the cavern surrounding rock under multiple blasting penetrations and cyclic blasting under different blasting schemes, including the impact test velocity gradient and different impact times.

[0127] Preferably, in one embodiment, in the damage permeability measurement step, the corresponding permeability coefficient is determined according to the following operation:

[0128] For surrounding rock samples with different damage variables after dynamic impact test, seepage characteristics test of rock samples was carried out by applying different gradients of osmotic pressure difference according to the set test parameters. The seepage characteristics of rock samples with different damage variables under different osmotic pressure conditions were determined according to the test results.

[0129] In practical applications, experimental studies on the seepage characteristics of rock samples with different damage variables are carried out; different gradients of osmotic pressure differences are applied to study the seepage characteristics of rock samples with different damage variables under different osmotic pressure conditions.

[0130] Furthermore, the permeability coefficients measured for rock samples with different damage variables are compared to obtain the corresponding relationship between the damage variable and the permeability coefficient of the rock sample. In practical applications, the corresponding permeability pressure difference and damage variable data can be associated and stored based on the determined seepage characteristics of the rock sample to form a damaged surrounding rock permeability coefficient relationship table for subsequent use. In practical applications, the data in the damaged surrounding rock permeability coefficient relationship table can be set to be distributed in partitions with the rock sample damage variable data as the index.

[0131] In an optional embodiment, several rock samples with the same or similar physical parameters can be selected to carry out single dynamic impact tests with velocity gradients of 4m / s, 5m / s, 6m / s, 7m / s, and 8m / s and cyclic dynamic impact tests (5 impacts) with velocity gradients of 4m / s, 6m / s, and 8m / s.

[0132] The longitudinal wave velocity of the damaged rock samples under different impact velocities and impact times was tested, and the longitudinal wave velocity of the rock samples before and after the impact was compared to determine the damage variables of the rock samples.

[0133] Conduct experimental research on the seepage characteristics of rock samples with different damage variables. Apply osmotic pressure differences of 0.2MPa, 0.4MPa and 0.6MPa respectively to study the seepage characteristics of rock samples with different damage variables under different osmotic pressure conditions.

[0134] The permeability coefficients measured for rock samples with different damage variables are compared to obtain the corresponding relationship between the damage variables and permeability coefficients of rock samples.

[0135] At present, when using numerical simulation methods to evaluate the water seal performance of underground water seal oil depots, most of the rocks around the cavern are equivalent to uniform continuous media, and the permeable rock mass is homogeneous. The present invention determines the evolution law of the permeability coefficient of the cavern surrounding rock under different degrees of dynamic damage through indoor experiments, and calculates the damage variables of the surrounding rock at different positions around the cavern under the action of cyclic blasting excavation through numerical simulation. Based on the test results and the conclusions of numerical simulation, the permeability coefficient is reasonably determined according to the degree of damage of different parts of the cavern surrounding rock. Based on this embodiment, the subsequent water seal evaluation can fully consider the adverse effects of the reduced integrity of the cavern surrounding rock and the increased permeability coefficient caused by cyclic blasting excavation on the water seal performance, making the evaluation results more accurate and reasonable.

[0136] After clarifying the damage distribution law of the surrounding rock of the underground water-seal oil depot under multiple blasting footages and cyclic blasting in different blasting schemes and its relationship with the permeability coefficient, a water seal performance evaluation is carried out based on the surrounding rock of the underground water-seal oil depot on site in the reservoir area with evaluation needs. Furthermore, the hydrogeological model establishment steps are performed: the hydrogeological parameters of the surrounding rock of the target underground water-seal oil depot are determined based on the on-site geological data of the target reservoir area, and a surrounding rock hydrogeological model of the current underground water-seal oil depot is constructed according to the hydrogeological parameters.

[0137] In an optional embodiment, a three-dimensional hydrogeological numerical calculation model of an underground water-sealed oil reservoir is established, such as Figure 6 shown.

[0138] Furthermore, a water seal performance evaluation step is implemented based on the surrounding rock hydrogeological model. The corresponding damage variables are determined according to the current blasting plan and working conditions of the surrounding rock. The surrounding rock hydrogeological model is assigned a permeability coefficient matching the damage variables. The water seal performance of the underground water seal oil reservoir is evaluated in combination with the groundwater level distribution, cavern water inflow and vertical hydraulic gradient data in the reservoir area.

[0139] In actual application, combined with the damage distribution of cavern surrounding rock under blasting vibration and the corresponding relationship between rock damage variables and permeability coefficient, based on the three-dimensional hydrogeological numerical calculation model, the surrounding rock at different positions and different depths from the cavern contour surface is assigned corresponding permeability coefficients according to its corresponding damage variable value and referring to the relationship between the damage variable and the permeability coefficient. Then, numerical simulation software is used to analyze the groundwater level distribution near the underground water-seal oil depot, the cavern water inflow and the vertical hydraulic gradient above the oil depot, and the water sealing performance of the underground water-seal oil depot is evaluated. Specifically, the numerical simulation software COMSOL Multiphysics can be used to analyze the groundwater level distribution near the underground water-seal oil depot, the cavern water inflow and the vertical hydraulic gradient above the oil depot, and the water sealing performance of the underground water-seal oil depot is evaluated.

[0140] By using the embodiment of the present invention, the cumulative damage effect of blasting vibration has an increasing effect on the permeability coefficient of the surrounding rock. According to the previous numerical simulation results of blasting vibration, the distribution range of surrounding rocks with different damage degrees can be obtained. Based on this, in the three-dimensional hydrogeological model, the permeability coefficients of surrounding rocks at different positions and at different depths from the cavern contour surface are set according to the size of their damage. Compared with the surrounding rock permeability coefficient being the same everywhere under a single uniform medium, the surrounding rock permeability coefficient in this method is not a constant, which will affect the calculation results of parameters such as water level distribution and water inflow, and further affect the water seal evaluation results; for example, an increase in the permeability coefficient will lead to an increase in water inflow, which will have an adverse effect on the water seal performance.

[0141] The embodiment of the present invention provides a method for evaluating the water seal performance of an underground water seal oil depot taking into account blasting vibration; a permeability coefficient is reasonably assigned according to the degree of damage to the surrounding rock of the cavern at different parts; and the water seal performance of the underground water seal oil depot is evaluated based on the groundwater level distribution near the underground water seal oil depot, the water inflow of the cavern and the vertical hydraulic gradient above the oil depot.

[0142] In the process of realizing the water seal performance evaluation of an underground water seal oil depot, an embodiment of the present invention provides an experimental method for determining the evolution law of the permeability coefficient of the surrounding rock of the underground water seal oil depot cavern under different degrees of dynamic damage. Samples with different degrees of dynamic damage are obtained through a dynamic impact test, and the sample damage variable is determined by the longitudinal wave velocity of the sample before and after the impact. The permeability coefficient of the samples with different degrees of dynamic damage is determined through a triaxial seepage test. Combined with the test results, the evolution law of the permeability coefficient of the cavern surrounding rock under different degrees of dynamic damage can be determined.

[0143] In addition, an embodiment of the present invention also provides a numerical simulation method for the surrounding rock damage of an underground water-sealed oil depot cavern under cyclic blasting, establishing a non-blasthole model of each excavation segment under a single footage; extracting the displacement boundary conditions of each excavation segment acting on the cavern contour surface under a single footage; establishing a cavern model; and simulating the blasting load by applying corresponding boundary conditions on the cavern contour surface to calculate the damage variables of the surrounding rock at different positions of the cavern under multi-footage cyclic blasting.

[0144] When the technical means of the embodiment of the present invention are used to realize the numerical simulation of the surrounding rock damage of the underground water-sealed oil depot cavern, the following advantages are possessed: first, compared with the numerical simulation method of establishing a blasthole model, the present method does not need to establish a large number of blastholes and explosive models with complex distribution, avoiding the difficulties in modeling and meshing, and ensuring that the simulation can proceed smoothly; secondly, compared with the method of using the blasting load equivalent method to establish a non-blasthole model, the present method only establishes a non-blasthole model of each excavation segment under a single footage to extract the boundary conditions of each excavation segment acting on the cavern contour surface, and simulates the blasting load by directly applying the boundary conditions on the cavern contour surface in the subsequent multi-footage cyclic blasting excavation process, avoiding the conventional non-blasthole model according to the complex process of cutting the model according to the detonator segment used under each footage and excavation segment, greatly improving the calculation efficiency. In addition, when the present invention realizes the evaluation of the water seal performance of the oil depot, the permeability coefficient matching the surrounding rock damage variable corresponding to the blasting scheme is used to perform a refined correction of the three-dimensional geological and hydrological model, so that the evaluation result of the water seal performance is more realistic and more accurate.

[0145] For the above-mentioned method embodiments, for the sake of simplicity, they are all described as a series of action combinations, but those skilled in the art should know that the present invention is not limited by the order of the actions described, because according to the present invention, some steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also know that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily required by the present invention.

[0146] It should be pointed out that in other embodiments of the present invention, the method can also obtain a new method for evaluating the water seal performance of a sealing cavern reservoir by combining one or several of the above embodiments, so as to achieve performance optimization and application improvement of underground water seal oil depots.

[0147] It should be noted that, based on the method in any one or more of the above-mentioned embodiments of the present invention, the present invention also provides a storage medium, on which is stored a program code that can implement the method as described in any one or more of the above-mentioned embodiments, and when the code is executed by the operating system, it can implement the water seal performance evaluation method of the sealing cavern reservoir based on the cumulative damage effect of blasting as described above.

[0148] Embodiment 2

[0149] The method is described in detail in the embodiments disclosed in the above invention. The method of the invention can be implemented by various devices or systems. Therefore, based on other aspects of the method described in any one or more embodiments, the present invention also provides a water seal performance evaluation system for underground water seal oil reservoir considering blasting vibration. The system is used to execute a water seal performance evaluation method for underground water seal oil reservoir considering blasting vibration described in any one or more embodiments. Specific embodiments are given below for detailed description.

[0150] Specifically, Figure 7 FIG. 4 is a schematic diagram showing a structure of a water seal performance evaluation system for an underground water seal oil reservoir taking into account blasting vibration provided in an embodiment of the present invention. Figure 7 As shown, the system includes:

[0151] The blasting vibration simulation module is configured to calculate the equivalent blasting load curve based on the construction parameters of the blasting plan, and to form a corresponding non-blasthole model of each excavation section of a single footage in combination with the material parameters of the reservoir area geology, and to obtain the blasting vibration simulation data of each excavation section through the solver calculation;

[0152] An action displacement analysis module is configured to extract the displacement time history curve of each excavation segment acting on the surrounding rock contour surface by using a post-processing system based on the blasting vibration simulation data, and determine the displacement boundary conditions corresponding to each excavation segment;

[0153] The damage distribution determination module is configured to apply corresponding boundary conditions on the cavern contour surface to simulate the blasting load, and obtain the damage variables of the surrounding rock at different positions around the underground water-sealed oil depot cavern under different working conditions under different blasting schemes and multi-footage cyclic blasting;

[0154] A surrounding rock sample preparation module, which is configured to drill holes in the formation range of the underground water-sealed oil reservoir to obtain core sections and process them to form surrounding rock samples that meet set standards;

[0155] The damaged permeability measurement module is configured to obtain physical and mechanical parameters based on surrounding rock samples through various types of tests, determine the rock sample damage variables after the wave velocity test in combination with the dynamic impact test, determine the corresponding permeability coefficient through tests based on rock samples with different degrees of damage, and record and form a relationship table of damaged surrounding rock permeability coefficients;

[0156] A hydrogeological model building module, which is configured to determine the hydrogeological parameters of the surrounding rock of the target underground water-sealed oil reservoir based on the on-site geological data of the target reservoir area, and to construct a surrounding rock hydrogeological model of the current underground water-sealed oil reservoir according to the physical and mechanical parameters;

[0157] The water seal performance evaluation module is configured to determine the corresponding damage variables according to the current blasting plan and working conditions of the surrounding rock, assign a permeability coefficient matching the damage variables to the surrounding rock hydrogeological model, and determine the water seal performance evaluation result of the underground water seal oil depot based on the surrounding rock hydrogeological model after the permeability coefficient is assigned.

[0158] In a preferred embodiment, the blasting vibration simulation module is configured as follows:

[0159] Collect and organize the excavation and blasting plans for underground water-sealed oil depot caverns, and determine the construction parameters of each excavation and blasting plan, including the distribution of blastholes in each excavation section, charging radius and length, explosive density and detonation velocity, and the delay of each detonator section and single-section charging information when using millisecond differential blasting.

[0160] Further, in an optional embodiment, the blasting vibration simulation module is configured to form a non-blasthole model of each excavation segment of a single footage based on the construction parameters of the blasting scheme according to the following operations:

[0161] According to the physical and mechanical parameters, the matching material equation is determined to describe the constitutive relationship of the surrounding rock of the underground water-sealed oil depot, and the parameters of the material equation are set to determine the material parameters of the surrounding rock of the current underground water-sealed oil depot;

[0162] The calculated equivalent blasting load curve that matches the construction parameters of the blasting scheme is applied to the corresponding equivalent action boundary to obtain a blasthole-free model of the corresponding blasting scheme.

[0163] Optionally, in one embodiment, the blasting vibration simulation module calculates the blasting vibration simulation data of each excavation segment according to the following operations:

[0164] After setting the no-blasthole model of the surrounding rock of the underground water-sealed oil depot cavern according to the setting requirements of the LS-DYNA software solver, the no-blasthole model of each segmented blasting excavation is submitted to the LS-DYNA software solver for calculation, and the corresponding solution log file is obtained as the blasting vibration simulation data result corresponding to the current no-blasthole model.

[0165] Furthermore, the action displacement analysis module is configured as follows: for the displacement time-history curve of the excavation segment acting on the surrounding rock contour surface, analyze the shape and peak characteristics of the curve, select representative nodes of a set scale and their corresponding point sets, and use the displacement time-history curve corresponding to the selected representative node as the displacement time-history curve of the excavation segment acting on the cavern contour surface of the blasting scheme.

[0166] Preferably, in one embodiment, the damage distribution determination module includes:

[0167] The surrounding rock overall model building unit is configured to build an overall cavern model by combining the physical and mechanical parameters of the surrounding rock and the shape and size data of the underground water-sealed oil depot cavern, using the corresponding material equation to describe the constitutive relationship of the model and setting the parameters of the material equation, and also applying a non-reflecting boundary condition;

[0168] A sequence correction unit is configured to determine the excavation sequence of each segment of each footage of the cavern, and to correct the time coordinates in the displacement time history curve of each representative point in different excavation segments under each footage in the blasting scheme according to the excavation sequence;

[0169] A displacement applying unit is configured to apply the displacement time history curves at the representative points in different excavation segments under different footages as displacement boundary conditions to the cavern model of the footage of the corresponding excavation segment, as a stage calculation model, and update the stage calculation model according to the excavation sequence combined with the solver until the required excavation footage is reached, and save the calculation model of the last stage as the target calculation model;

[0170] The damage distribution analysis module is configured to import the solution file of the target calculation model into the post-processing software to obtain the damage variables of the surrounding rock at different positions around the cavern under the blasting conditions corresponding to multiple blasting footage cycles.

[0171] Furthermore, in one embodiment, the damage permeability measurement module obtains the physical and mechanical parameters of the surrounding rock sample by the following operations:

[0172] Determine the physical parameter values ​​of the prepared surrounding rock samples based on wave velocity test and density test;

[0173] The rock mechanical parameters of the prepared surrounding rock specimens were determined based on uniaxial compression test, Brazilian splitting test and triaxial compression test.

[0174] In a preferred embodiment, the damage permeability measurement module is configured to determine the rock sample damage variable after the wave velocity test in combination with the dynamic impact test according to the following operations:

[0175] Based on the physical and mechanical parameters, surrounding rock samples whose parameter similarity meets the set requirements are selected as impact test rock samples, different dynamic impact tests are carried out on these rock samples, and the longitudinal wave velocity of the rock samples after impact is measured, and the damage variable data of the impact test rock samples are determined according to the change of the longitudinal wave velocity of the rock samples before and after impact;

[0176] Among them, the test parameters of the dynamic impact test are set according to the damage variables corresponding to multi-footprint cyclic blasting in different blasting schemes.

[0177] In the underground water seal oil reservoir water seal performance evaluation system considering blasting vibration provided by the embodiment of the present invention, each module or unit structure can be operated independently or in combination according to actual test setting requirements and data calculation requirements to achieve corresponding technical effects.

[0178] It should be understood that the embodiments disclosed in the present invention are not limited to the specific structures, processing steps or materials disclosed herein, but should be extended to equivalent substitutions of these features understood by ordinary technicians in the relevant field. It should also be understood that the terms used herein are only used for the purpose of describing specific embodiments and are not meant to be limiting.

[0179] The "one embodiment" mentioned in the specification means that a particular feature, structure or characteristic described in conjunction with the embodiment is included in at least one embodiment of the present invention. Therefore, the phrase "one embodiment" appearing in various places throughout the specification does not necessarily refer to the same embodiment.

[0180] Although the embodiments disclosed in the present invention are as above, the above contents are only embodiments adopted for facilitating the understanding of the present invention and are not intended to limit the present invention. Any technician in the technical field to which the present invention belongs can make any modifications and changes in the form and details of the implementation without departing from the spirit and scope disclosed in the present invention, but the patent protection scope of the present invention shall still be subject to the scope defined in the attached claims.

Claims

1. A method for evaluating the water seal performance of an underground water seal oil reservoir considering blasting vibration, characterized in that: The method comprises: Blasting vibration simulation steps: Calculate the equivalent blasting load curve based on the construction parameters of the blasting plan, and form the corresponding non-blasthole model of each excavation section of the single footage in combination with the material parameters of the reservoir area geology. Calculate the blasting vibration simulation data of each excavation section through the solver; Action displacement analysis step: based on the blasting vibration simulation data, using a post-processing system to extract the displacement time history curve of each excavation segment acting on the surrounding rock contour surface, and determine the displacement boundary conditions corresponding to each excavation segment; Damage distribution determination steps: Apply corresponding boundary conditions on the cavern contour surface to simulate blasting loads, and obtain damage variables at different locations around the surrounding rock of the underground water-sealed oil depot under multi-footage cyclic blasting of different blasting schemes; The surrounding rock sample preparation steps are as follows: drilling a hole in the formation range of the underground water-sealed oil depot to obtain a core section and processing it to form a surrounding rock sample that meets the set standards; Damage permeability measurement steps: Based on the surrounding rock samples, physical and mechanical parameters are obtained through various types of tests, and the rock sample damage variables after the wave velocity test are determined in combination with the dynamic impact test. Based on the rock samples with different degrees of damage, the corresponding permeability coefficients are determined through tests, and the damaged surrounding rock permeability coefficient relationship table is recorded; The hydrogeological model establishment step: determining the hydrogeological parameters of the surrounding rock of the target underground water-sealed oil reservoir based on the on-site geological data of the target reservoir area, and constructing the surrounding rock hydrogeological model of the current underground water-sealed oil reservoir according to the hydrogeological parameters; Water seal performance evaluation step: determine the corresponding damage variable according to the current blasting plan and working conditions of the surrounding rock, assign a permeability coefficient matching the damage variable to the surrounding rock hydrogeological model, and determine the water seal performance evaluation result of the underground water seal oil depot based on the surrounding rock hydrogeological model after the permeability coefficient is assigned.

2. The method according to claim 1, characterized in that The blasting vibration simulation step includes: collecting and arranging the excavation and blasting plans of the underground water-sealed oil depot caverns, and determining the construction parameters of each excavation and blasting plan, including the distribution of blastholes in each excavation section, the charging radius and length, the density and detonation velocity of explosives, and the delay of each detonator section and the single-section charging amount information when using millisecond differential blasting.

3. The method according to claim 1, characterized in that In the action displacement analysis step, the shape and peak characteristics of the displacement time-history curve of the excavation segment acting on the surrounding rock contour surface are analyzed, and the representative nodes and their corresponding point sets of the set scale are selected. The displacement time-history curve corresponding to the selected representative node is used as the displacement time-history curve of the excavation segment acting on the cavern contour surface of the blasting scheme.

4. The method according to claim 1, characterized in that: The damage distribution determination step includes the following operations: The steps of building the overall model of the surrounding rock are as follows: the overall cavern model is built by combining the physical and mechanical parameters of the surrounding rock and the shape and size data of the underground water-sealed oil depot cavern. The corresponding material equation is used to describe the constitutive relationship of the model and set the parameters of the material equation. In addition, the non-reflecting boundary condition is applied; Sequence correction step: determine the excavation sequence of each section of each footage of the cavern, and correct the time coordinates in the displacement time history curve of each representative point in different excavation sections under each footage in the blasting plan according to the excavation sequence; Displacement application step: The displacement time history curves at the representative points in different excavation segments under different footages after correction are applied as displacement boundary conditions to the cavern model of the footage of the corresponding excavation segment, as a stage calculation model, and the stage calculation model is updated according to the excavation sequence and the solver until the required excavation footage is met, and the calculation model of the last stage is saved as the target calculation model; Damage distribution analysis step: import the solution file of the target calculation model into the post-processing software to obtain the damage variables of the surrounding rock at different positions around the cavern under the blasting conditions corresponding to multiple blasting footage cycles.

5. The method according to claim 1, characterized in that In the damage permeability measurement step, the physical and mechanical parameters of the surrounding rock sample are obtained by the following operations: Determine the physical parameter values ​​of the prepared surrounding rock samples based on wave velocity test and density test; The rock mechanical parameters of the prepared surrounding rock specimens were determined based on uniaxial compression test, Brazilian splitting test and triaxial compression test.

6. The method according to claim 1, characterized in that In the damage permeability measurement step, the process of determining the rock sample damage variable after the wave velocity test in combination with the dynamic impact test includes: Based on the physical and mechanical parameters, surrounding rock samples whose parameter similarity meets the set requirements are selected as impact test rock samples, different dynamic impact tests are carried out on these rock samples, and the longitudinal wave velocity of the rock samples after impact is measured, and the damage variable data of the impact test rock samples are determined according to the change of the longitudinal wave velocity of the rock samples before and after impact; Among them, the test parameters of the dynamic impact test are set according to the damage variables corresponding to multi-footprint cyclic blasting in different blasting schemes.

7. The method according to claim 1, characterized in that In the water sealing performance evaluation step, based on the surrounding rock hydrogeological model and with reference to the damaged surrounding rock permeability coefficient relationship table, the surrounding rocks at different positions and at different depths from the cavern contour surface are assigned corresponding permeability coefficients according to their corresponding damage variable values.

8. A storage medium, characterized in that: The storage medium stores program codes that can implement the method as claimed in any one of claims 1 to 7.

9. A water seal performance evaluation system for underground water seal oil reservoir considering blasting vibration, characterized in that: The system executes the method according to any one of claims 1 to 7.

Images