Method for judging stability of initial support of underground gas storage cavern of compressed air energy storage power station

Abstract

The application provides a kind of stability discrimination method of underground gas storage cavern initial support of compressed air energy storage power station, the method comprises: considering the expansion force and softening of hydrophilic surrounding rock of underground gas storage cavern, draw the response curve of surrounding rock in humidification process;Obtain the supporting parameters of underground gas storage cavern, calculate and draw the characteristic curve of supporting structure;The intersection point of the response curve of surrounding rock and the characteristic curve of supporting structure is determined, and the coordinate of the intersection point is obtained according to the coordinate of the intersection point, and the equilibrium supporting force of hydrophilic surrounding rock and supporting balance is obtained according to the coordinate of the intersection point;According to the safety factor of underground gas storage cavern, the stability of the cavern is judged according to the safety factor.The application fully considers the expansion force, softening and supporting force effect of surrounding rock in the relationship between surrounding rock and support, and uses safety factor as the stability index of underground gas storage cavern, which is suitable for the stability evaluation of underground cavern with complex surrounding rock characteristics, and the discrimination method is accurate and efficient.

Description

Technical Field

[0001] This invention relates to the field of engineering safety technology, specifically to a method for determining the stability of the initial support of the underground gas storage chamber of a compressed air storage power station and a device for determining the stability of the initial support of the underground gas storage chamber of a compressed air storage power station. Background Technology

[0002] Compressed air storage power stations are a new type of energy storage system with advantages such as fast dynamic response, high economic performance, and low environmental pollution. They can play a role in load balancing, strategic planning, and improving power supply quality. However, underground chamber projects such as underground gas storage facilities for compressed air storage power stations are often characterized by great depth and complex geological conditions. In particular, when the chamber passes through hydrophilic surrounding rock, it is prone to large deformation of the surrounding rock, failure of initial support, and even collapse, seriously affecting the quality and safety of the project.

[0003] Hydrophilic surrounding rocks contain a high amount of clay minerals such as montmorillonite and illite, resulting in low rock strength and high porosity. After excavation, the surrounding rock undergoes stress release and water immersion, causing not only volume expansion but also a decrease in strength with increasing water content, exhibiting typical softening characteristics. This leads to plastic extrusion of the surrounding rock into the tunnel or floor bulging, while simultaneously exerting expansion pressure on the tunnel structures, ultimately causing failure of the tunnel support structure and affecting tunnel stability. Initial support refers to the timely support implemented after tunnel excavation to control surrounding rock deformation and prevent collapse.

[0004] In related technologies, the initial support design of underground gas storage chambers mainly adopts the method of empirical analogy, which assumes that the error caused by factors is relatively large, and lacks a systematic, scientific method that can accurately and quantitatively determine the stability of the designed support. Summary of the Invention

[0005] To address the aforementioned technical problems, the first objective of this invention is to propose a method for determining the stability of the initial support of the underground gas storage chamber in a compressed air storage power station.

[0006] The second aspect of this invention is to provide a stability determination device for the initial support of the underground gas storage chamber of a compressed air energy storage power station.

[0007] The technical solution adopted in this invention is as follows:

[0008] A first aspect of the present invention provides a method for determining the stability of the initial support of an underground gas storage chamber in a compressed air storage power station, comprising the following steps: calculating the mathematical relationship between the radial displacement at the free face of the surrounding rock and the support force, based on the expansion force and softening properties of the hydrophilic surrounding rock of the underground gas storage chamber, and plotting the surrounding rock response curve during the humidification process; obtaining the support parameters of the underground gas storage chamber, calculating and plotting the support structure characteristic curve based on the support parameters; combining the surrounding rock response curve and the support structure characteristic curve to determine the coordinates of the intersection point of the surrounding rock response curve and the support structure characteristic curve, and obtaining the equilibrium support force when the hydrophilic surrounding rock and the support are in equilibrium based on the coordinates of the intersection point; calculating the safety factor of the underground gas storage chamber based on the equilibrium support force and the ultimate support force of the combined support structure; and determining the stability state of the underground gas storage chamber based on the safety factor.

[0009] The stability determination method for the initial support of the underground gas storage chamber of the compressed air storage power station proposed in this invention may also have the following additional technical features:

[0010] According to one embodiment of the present invention, the mathematical relationship between the radial displacement of the free face of the surrounding rock and the support force is specifically calculated according to the following formula:

[0011] ;

[0012] ;

[0013] In the formula, R0 is the radius of the chamber, P0 is the ground stress, and P s For support force, R P This is the area of ​​plastic deformation of the surrounding rock. It is the radial displacement at the free face of the surrounding rock. It is the cohesion of the surrounding rock. It is the internal friction angle of the surrounding rock. It is the elastic modulus of the surrounding rock. It is the Poisson's ratio of the surrounding rock. It is the radial stress at the elastic-plastic interface of the surrounding rock. P0 is the swelling force of the surrounding rock, and P0 is the in-situ stress.

[0014] in, ;

[0015] ;

[0016] ;

[0017] ;

[0018] In the formula, The expansion force is The water content of the surrounding rock at that time and These are the initial water content and the final saturated water content of the surrounding rock, respectively. The final water content of the surrounding rock The corresponding expansion force, , , and These are the first to fourth coefficients, respectively.

[0019] According to one embodiment of the present invention, calculating and plotting the characteristic curve of the support structure based on the support parameters specifically includes: calculating the support force of each support unit in the combined support structure of the surrounding rock according to the characteristic equation of the support unit of the surrounding rock, wherein the support force of the support unit includes: the maximum support force of shotcrete and the maximum support force of anchor bolts; obtaining the ultimate support force and ultimate deformation of the combined support structure based on the support force of each support unit; obtaining the overall stiffness of the combined support structure based on the ultimate support force and ultimate deformation of the combined support structure; calculating the displacement of the free surface at the support starting position; and plotting the characteristic curve of the support structure based on the ultimate support force, the overall stiffness, and the displacement of the free surface at the support starting position.

[0020] According to one embodiment of the present invention, the safety factor of the underground gas storage chamber is specifically calculated according to the following formula: ;in, The safety factor is... The ultimate support force, This refers to the balancing support force.

[0021] According to one embodiment of the present invention, determining the stable state of the underground gas storage chamber based on the safety factor specifically includes: determining whether the safety factor is greater than 1; if the safety factor is greater than 1, then determining that the underground gas storage chamber is in a stable state; if the safety factor is less than or equal to 1, then determining that the underground gas storage chamber is in an unstable state.

[0022] A second aspect of the present invention provides a stability determination device for the initial support of an underground gas storage chamber in a compressed air storage power station, comprising: a first drawing module, which is used to calculate the mathematical relationship between the radial displacement at the free face of the surrounding rock and the support force by combining the expansion force and softening property of the hydrophilic surrounding rock of the underground gas storage chamber, and to draw the response curve of the surrounding rock during the humidification process; and a second drawing module, which is used to obtain the support parameters of the underground gas storage chamber, and to calculate and draw the characteristic curve of the support structure based on the support parameters. The system includes: an acquisition module, which combines the surrounding rock response curve with the support structure characteristic curve to determine the coordinates of the intersection point of the surrounding rock response curve and the support structure characteristic curve, and obtains the equilibrium support force when the hydrophilic surrounding rock and the support are in equilibrium based on the coordinates of the intersection point; a calculation module, which calculates the safety factor of the underground gas storage chamber based on the equilibrium support force and the ultimate support force of the combined support structure; and a judgment module, which judges the stability state of the underground gas storage chamber based on the safety factor.

[0023] The stability determination device for the initial support of the underground gas storage chamber of the compressed air storage power station described above in this invention also has the following additional technical features:

[0024] According to one embodiment of the present invention, the first drawing module specifically calculates the mathematical relationship between the radial displacement of the free face of the surrounding rock and the support force based on the following formula:

[0025] ;

[0026] ;

[0027] In the formula, R0 is the radius of the chamber, P0 is the ground stress, and P s For support force, R P This is the area of ​​plastic deformation of the surrounding rock. It is the radial displacement at the free face of the surrounding rock. It is the cohesion of the surrounding rock. It is the internal friction angle of the surrounding rock. It is the elastic modulus of the surrounding rock. It is the Poisson's ratio of the surrounding rock. It is the radial stress at the elastic-plastic interface of the surrounding rock. P0 is the swelling force of the surrounding rock, and P0 is the in-situ stress.

[0028] in, ;

[0029] ;

[0030] ;

[0031] ;

[0032] In the formula, The expansion force is The water content of the surrounding rock at that time and These are the initial water content and the final saturated water content of the surrounding rock, respectively. The final water content of the surrounding rock The corresponding expansion force, , , and These are the first to fourth coefficients, respectively.

[0033] According to one embodiment of the present invention, the second drawing module is specifically used for: calculating the support force of each support unit of the surrounding rock composite support structure based on the characteristic equation of the support unit of the surrounding rock, wherein the support force of the support unit includes: the maximum support force of shotcrete and the maximum support force of anchor bolts; obtaining the ultimate support force and ultimate deformation of the composite support structure based on the support force of each support unit; obtaining the overall stiffness of the composite support structure based on the ultimate support force and ultimate deformation of the composite support structure; calculating the displacement of the free surface at the support starting position; and drawing the characteristic curve of the support structure based on the ultimate support force, the overall stiffness, and the displacement of the free surface at the support starting position.

[0034] According to one embodiment of the present invention, the calculation module specifically calculates the safety factor of the underground gas storage chamber according to the following formula: ;in, The safety factor is... The ultimate support force, This refers to the balancing support force.

[0035] According to one embodiment of the present invention, the judgment module is specifically used to: determine whether the safety factor is greater than 1; if the safety factor is greater than 1, then determine that the underground gas storage chamber is in a stable state; if the safety factor is less than or equal to 1, then determine that the underground gas storage chamber is in an unstable state.

[0036] The beneficial effects of this invention are:

[0037] This invention fully considers the swelling force, softening force, and support effect of the surrounding rock in the relationship between surrounding rock and support, and uses the safety factor as the stability index of underground gas storage chambers. It is applicable to the stability evaluation of underground chambers with complex surrounding rock characteristics, and the discrimination method is accurate and efficient. Attached Figure Description

[0038] Figure 1 This is a flowchart of a method for determining the stability of the initial support of the underground gas storage chamber of a compressed air storage power station according to an embodiment of the present invention;

[0039] Figure 2 This is a schematic diagram of the surrounding rock response curve and the support structure characteristic curve according to an embodiment of the present invention;

[0040] Figure 3 This is a flowchart of a stability determination method for the initial support of the underground gas storage chamber of a compressed air storage power station according to another embodiment of the present invention;

[0041] Figure 4 This is a block diagram of a stability determination device for the initial support of the underground gas storage chamber of a compressed air storage power station according to an embodiment of the present invention. Detailed Implementation

[0042] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0043] Figure 1 This is a flowchart illustrating a method for determining the stability of the initial support of the underground gas storage chamber in a compressed air storage power station according to an embodiment of the present invention. Figure 1 As shown, the method includes the following steps:

[0044] S1. Based on the expansion force and softening property of the hydrophilic surrounding rock in the underground gas storage chamber, calculate the mathematical relationship between the radial displacement and the support force at the free face of the surrounding rock, and plot the response curve of the surrounding rock during the humidification process.

[0045] Specifically, based on the theories of elasticity and plasticity, and according to the deformation of the surrounding rock, the surrounding rock of the chamber is divided into a plastic zone and an elastic zone. In the analytical solution of the elastic-plastic relationship of a circular axisymmetric chamber, an expansion force is introduced. Establish a formula for solving the displacement of the hydrophilic surrounding rock chamber, and obtain the mathematical relationship between the radial displacement of its free face and the support force, that is, the response curve of the hydrophilic surrounding rock chamber, as shown in equations (1)-(3).

[0046] (1);

[0047] (2);

[0048] In the formula, R0 is the radius of the chamber, P0 is the ground stress, and P s For support force, R P This is the area of ​​plastic deformation of the surrounding rock. It is the radial displacement at the free face of the surrounding rock. It is the cohesion of the surrounding rock. It is the internal friction angle of the surrounding rock. It is the elastic modulus of the surrounding rock. It is the Poisson's ratio of the surrounding rock. It is the radial stress at the elastic-plastic interface of the surrounding rock. P0 is the swelling force of the surrounding rock, and P0 is the in-situ stress. It can be measured by methods such as hydraulic fracturing and stress relief. When there is no measured data of in-situ stress, the in-situ stress can be temporarily replaced by the self-weight stress.

[0049] ; (3)

[0050] Existing studies have shown that during the process of wetting from a natural state to a saturated state, there is a significant linear relationship between the water content of the surrounding rock and the swelling force, as shown in the following equation (4):

[0051] (4);

[0052] In the formula, The expansion force is The water content of the surrounding rock at that time and These are the initial water content and the final saturated water content of the surrounding rock, respectively. The final water content of the surrounding rock The corresponding expansion force.

[0053] In fact, during the moistening process of hydrophilic surrounding rock, it not only exhibits expansion characteristics, but also has typical softening characteristics. Its cohesion and internal friction angle gradually decrease with the increase of water content. This attenuation relationship is shown in equations (5) and (6).

[0054] (5);

[0055] (6);

[0056] In the formula, , , and These are the first to fourth coefficients, which are fitted in advance using experimental data.

[0057] Substituting equations (4), (5), and (6) into equations (1), (2), and (3), we can obtain the response curve of the surrounding rock during the humidification process, as follows: Figure 2 The curve L1 in the figure is shown. The surrounding rock response curve during the humidification process is a function of the displacement of the surrounding rock with the water content and support parameters, and can describe the influence of the humidification process on the displacement of the surrounding rock.

[0058] In other words, the mathematical relationship between the radial displacement of the free face of the surrounding rock and the support force can be calculated according to formulas (1)-(6), so as to draw the response curve of the surrounding rock during the humidification process.

[0059] S2, obtain the support parameters of the underground gas storage chamber, and calculate and draw the characteristic curve of the support structure based on the support parameters.

[0060] Furthermore, according to one embodiment of the present invention, such as Figure 3 As shown, the characteristic curves of the support structure are calculated and plotted based on the support parameters, specifically including:

[0061] S21. Calculate the support force of each support unit in the combined support structure of the surrounding rock according to the characteristic equation of the support unit of the surrounding rock. The support force of the support unit includes: the maximum support force of shotcrete and the maximum support force of anchor bolts.

[0062] Specifically, the maximum support force of shotcrete It can be obtained according to the following formula (7):

[0063] (7)

[0064] In the formula, This refers to the shear strength of concrete, which is generally 20% to 43% of its compressive strength. It refers to the thickness of the sprayed concrete layer; The shear failure angle of shotcrete is generally taken as 30°; It is the internal friction angle of the surrounding rock.

[0065] Maximum support force of anchor bolts It can be obtained according to the following formulas (8)-(11):

[0066] (8);

[0067] (9);

[0068] (10);

[0069] (11);

[0070] In the formula, R0 is the radius of the chamber. The length of the anchor bolt. The average circumferential spacing of the anchor bolts. The average spacing along the axial direction of the chamber. It is the internal friction angle of the surrounding rock. This refers to the final failure load in the anchor pull-out test. The maximum dip angle of the rock slip line. For rock shear failure angle, The thickness of the rock-bearing arch.

[0071] S22, obtain the ultimate support force and ultimate deformation of the combined support structure based on the support force of each support unit.

[0072] Specifically, without considering the coordinated deformation characteristics between supports, the maximum support forces of each support unit in the composite support structure are added together to obtain the ultimate support force of the composite support structure. for:

[0073] (12);

[0074] The shotcrete in each unit has the highest stiffness, thus allowing the smallest deformation. Therefore, the ultimate deformation of the composite support structure is... This represents the ultimate deformation of concrete, namely:

[0075] (13);

[0076] In the formula, This refers to the maximum deformation of shotcrete. It can be based on the stiffness of the shotcrete. and the maximum support force of shotcrete The results are as follows: (14) and (15):

[0077] (14);

[0078] (15);

[0079] In the formula, , These are the elastic modulus and Poisson's ratio of shotcrete, respectively. It refers to the thickness of the sprayed concrete layer.

[0080] S23, obtain the overall stiffness of the composite support structure based on the ultimate support force and ultimate deformation of the composite support structure.

[0081] Specifically, given that the stability of the chamber structure depends on the absence of damage to its individual support units, i.e., if the ultimate deformation of the combined support structure during the secondary stress release process of the surrounding rock does not exceed the ultimate deformation of the concrete... The support structure is stable. Therefore, the ultimate support force of its combined support structure is obtained. Rather than extreme deformation The relationship is:

[0082] (16);

[0083] In the formula, To represent the overall stiffness of the combined support structure, the slope (support force / displacement) of the characteristic curve of the support structure is expressed in the relationship between the surrounding rock and the support. It is affected by the diversity of support structure materials and their mutual coupling effects.

[0084] S24, calculate the displacement of the free surface at the starting position of the support.

[0085] Specifically, the distance L between the starting position of the support and the working face of the surrounding rock and the radial displacement of the free face at the starting position. The relationship between them, namely the radial displacement of the unsupported section of the tunnel along the excavation direction, is expressed mathematically as follows:

[0086] (17);

[0087] In the formula, This represents the maximum radial displacement of the free face under the condition that the surrounding rock does not collapse.

[0088] S25. Draw the characteristic curve of the support structure based on the ultimate support force, overall stiffness, and displacement of the free surface at the initial support position.

[0089] like Figure 2 As shown, combined with ultimate support force Overall stiffness (i.e., the slope of the characteristic curve of the support structure) and the displacement of the free surface at the starting position of the support. This allows you to plot the characteristic curves of the support structure. The characteristic curves of the support structure can be referenced as follows: Figure 2 The curve L2 is shown in the figure. Figure 2 L in the figure represents the distance between the starting position of the support and the working face of the surrounding rock.

[0090] S3, combine the surrounding rock response curve and the support structure characteristic curve, determine the coordinates of the intersection point of the surrounding rock response curve and the support structure characteristic curve, and obtain the balanced support force when the hydrophilic surrounding rock and the support are in equilibrium based on the coordinates of the intersection point.

[0091] Specifically, by combining the surrounding rock response curve and the support structure characteristic curve, the coordinates of the intersection point of the two curves are determined. , This refers to the displacement of the free face and the support force (balanced support force) when the hydrophilic surrounding rock and the support are in equilibrium.

[0092] S4. Calculate the safety factor of the underground gas storage chamber based on the balanced support force and the ultimate support force of the combined support structure.

[0093] Furthermore, according to one embodiment of the present invention, the safety factor of the underground gas storage chamber can be calculated according to the following formula:

[0094] (18);

[0095] in, For safety reasons, For ultimate support force, To balance the support force.

[0096] S5, determine the stability of the underground gas storage chamber based on the safety factor.

[0097] Furthermore, according to one embodiment of the present invention, determining the stable state of the underground gas storage chamber based on the safety factor specifically includes: determining whether the safety factor is greater than 1; if the safety factor is greater than 1, then determining that the underground gas storage chamber is in a stable state; if the safety factor is less than or equal to 1, then determining that the underground gas storage chamber is in an unstable state.

[0098] If the underground gas storage chamber is determined to be in an unstable state, it indicates that the support design is unreasonable and the safety factor needs to be adjusted.

[0099] In summary, the stability assessment method for the initial support of the underground gas storage chamber of the compressed air storage power station according to the embodiments of the present invention fully considers the expansion force, softening effect and support force of the surrounding rock in the relationship between the surrounding rock and the support. It can also quantitatively consider the influence of the support effects of concrete, anchor bolts and their combinations on the stability of the hydrophilic surrounding rock chamber, and uses the safety factor as the stability index of the underground gas storage chamber. It is suitable for the stability evaluation of underground chambers with complex surrounding rock characteristics, and the assessment method is accurate and efficient.

[0100] Corresponding to the aforementioned method for determining the stability of the initial support of the underground gas storage chamber in a compressed air storage power station, this invention also proposes a device for determining the stability of the initial support of the underground gas storage chamber in a compressed air storage power station. Since the device embodiments of this invention correspond to the aforementioned method embodiments, details not disclosed in the device embodiments can be referred to in the aforementioned method embodiments, and will not be repeated here.

[0101] Figure 4 This is a block diagram of a stability determination device for the initial support of the underground gas storage chamber of a compressed air storage power station according to an embodiment of the present invention. Figure 4 As shown, the device includes: a first drawing module 1, a second drawing module 2, an acquisition module 3, a calculation module 4, and a judgment module 5.

[0102] The system comprises the following modules: First, the plotting module 1, which calculates the mathematical relationship between the radial displacement of the free face of the surrounding rock and the support force by combining the expansion force and softening properties of the hydrophilic surrounding rock in the underground gas storage chamber, and plots the surrounding rock response curve during the humidification process; Second, the plotting module 2, which obtains the support parameters of the underground gas storage chamber, calculates and plots the support structure characteristic curve based on the support parameters; Acquisition module 3, which combines the surrounding rock response curve and the support structure characteristic curve, determines the coordinates of the intersection point of the surrounding rock response curve and the support structure characteristic curve, and obtains the equilibrium support force when the hydrophilic surrounding rock and the support are in equilibrium based on the coordinates of the intersection point; Calculation module 4, which calculates the safety factor of the underground gas storage chamber based on the equilibrium support force and the ultimate support force of the combined support structure; and Judgment module 5, which judges the stability state of the underground gas storage chamber based on the safety factor.

[0103] According to one embodiment of the present invention, the first drawing module 1 specifically calculates the mathematical relationship between the radial displacement of the free face of the surrounding rock and the support force based on the following formula:

[0104] ;

[0105] ;

[0106] In the formula, R0 is the radius of the chamber, P0 is the ground stress, and P s For support force, R P This is the area of ​​plastic deformation of the surrounding rock. It is the radial displacement at the free face of the surrounding rock. It is the cohesion of the surrounding rock. It is the internal friction angle of the surrounding rock. It is the elastic modulus of the surrounding rock. It is the Poisson's ratio of the surrounding rock. It is the radial stress at the elastic-plastic interface of the surrounding rock. P0 is the swelling force of the surrounding rock, and P0 is the in-situ stress.

[0107] in, ;

[0108] ;

[0109] ;

[0110] ;

[0111] In the formula, The expansion force is The water content of the surrounding rock at that time and These are the initial water content and the final saturated water content of the surrounding rock, respectively. The final water content of the surrounding rock The corresponding expansion force, , , and These are the first to fourth coefficients, respectively.

[0112] According to one embodiment of the present invention, the second drawing module 2 is specifically used for: calculating the support force of each support unit of the surrounding rock composite support structure based on the characteristic equation of the support unit of the surrounding rock, wherein the support force of the support unit includes: the maximum support force of shotcrete and the maximum support force of anchor bolts; obtaining the ultimate support force and ultimate deformation of the composite support structure based on the support force of each support unit; obtaining the overall stiffness of the composite support structure based on the ultimate support force and ultimate deformation of the composite support structure; calculating the displacement of the free surface at the support starting position; and drawing the characteristic curve of the support structure based on the ultimate support force, overall stiffness, and displacement of the free surface at the support starting position.

[0113] According to one embodiment of the present invention, the calculation module 4 specifically calculates the safety factor of the underground gas storage chamber according to the following formula: ;in, For safety reasons, For ultimate support force, To balance the support force.

[0114] According to one embodiment of the present invention, the judgment module 5 is specifically used to: determine whether the safety factor is greater than 1; if the safety factor is greater than 1, then determine that the underground gas storage chamber is in a stable state; if the safety factor is less than or equal to 1, then determine that the underground gas storage chamber is in an unstable state.

[0115] In summary, the stability discrimination device for the initial support of the underground gas storage chamber of the compressed gas storage power station according to the embodiments of the present invention fully considers the expansion force, softening force and support effect of the surrounding rock in the relationship between the surrounding rock and the support, and uses the safety factor as the stability index of the underground gas storage chamber. It is suitable for the stability evaluation of underground chambers with complex surrounding rock characteristics, and the discrimination method is accurate and efficient.

[0116] In the description of this invention, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. "A plurality of" means two or more, unless otherwise explicitly specified.

[0117] In this specification, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, those skilled in the art can combine and integrate the different embodiments or examples and features described in this specification without contradiction. Furthermore, those skilled in the art can combine and integrate the different embodiments or examples described herein, as well as the features of the different embodiments or examples, without contradiction.

[0118] Any process or method description in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or more executable instructions for implementing custom logic functions or processes, and the scope of preferred embodiments of the invention includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the functions involved, as should be understood by those skilled in the art to which embodiments of the invention pertain.

[0119] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include: an electrical connection having one or more wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Alternatively, the computer-readable medium may be paper or other suitable media on which the program can be printed, since the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in a computer memory.

[0120] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware as in another embodiment, it can be implemented using any of the following techniques known in the art, or a combination thereof: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0121] Those skilled in the art will understand that all or part of the steps of the methods in the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, the program includes one or a combination of the steps of the method embodiments.

[0122] Furthermore, the functional units in the various embodiments of the present invention can be integrated into a processing module, or each unit can exist physically separately, or two or more units can be integrated into a module. The integrated module can be implemented in hardware or as a software functional module. If the integrated module is implemented as a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium.

[0123] The storage medium mentioned above can be a read-only memory, a disk, or an optical disk, etc. Although embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

[0124] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for judging the stability of initial support of a cavern of a compressed air energy storage underground gas storage, characterized by, The method comprises the following steps: The mathematical relationship between the radial displacement of the free surface of the surrounding rock and the supporting force is calculated in combination with the swelling force and softening property of the hydrophilic surrounding rock of the underground gas storage cavern, and a surrounding rock response curve in the humidification process is drawn; Supporting parameters of the underground gas storage cavern are obtained, and a supporting structure characteristic curve is calculated and drawn according to the supporting parameters; The coordinates of the intersection point of the surrounding rock response curve and the supporting structure characteristic curve are determined, and the balanced supporting force when the hydrophilic surrounding rock and the support are balanced is obtained according to the coordinates of the intersection point; The safety factor of the underground gas storage cavern is calculated according to the balanced supporting force and the limit supporting force of the combined supporting structure; The stability state of the underground gas storage cavern is judged according to the safety factor; The mathematical relationship between the radial displacement of the free surface of the surrounding rock and the supporting force is calculated according to the following formula: ； ； wherein R0 is the chamber radius, P0 is the ground stress, P s is the support force, R P is the plastic deformation zone of the surrounding rock, is the radial displacement at the free surface of the surrounding rock, is the cohesion of the surrounding rock, is the internal friction angle of the surrounding rock, is the elastic modulus of the surrounding rock, is the Poisson's ratio of the surrounding rock, is the radial stress at the elastic-plastic boundary of the surrounding rock, is the swelling pressure of the surrounding rock; wherein ; ； ； ； wherein, is the swelling force for the water content of the surrounding rock, and are the initial water content of the surrounding rock and the final water content of the saturated surrounding rock, respectively, is the final water content of the surrounding rock the corresponding swelling force, , , and are the first to fourth coefficients, respectively.

2. The method according to claim 1, wherein the method is characterized by: The supporting structure characteristic curve is calculated and drawn according to the supporting parameters, specifically including: The supporting force of each supporting unit in the combined supporting structure of the surrounding rock is calculated according to the supporting unit characteristic equation of the surrounding rock, including the maximum supporting force of the shotcrete and the maximum supporting force of the anchor rod; The limit supporting force and the limit deformation of the combined supporting structure are obtained according to the supporting force of each supporting unit; The overall stiffness of the combined supporting structure is obtained according to the limit supporting force and the limit deformation of the combined supporting structure; The free surface displacement at the supporting starting position is calculated; The supporting structure characteristic curve is drawn according to the limit supporting force, the overall stiffness and the free surface displacement at the supporting starting position.

3. The method according to claim 1, wherein the method is characterized by: The safety factor of the underground gas storage cavern is calculated according to the following formula: ； wherein, is the safety factor, is the limit support force, is the equilibrium support force.

4. The method according to claim 1, wherein the method is characterized by: The stability state of the underground gas storage cavern is judged according to the safety factor, specifically including: It is judged whether the safety factor is greater than 1; If the safety factor is greater than 1, it is judged that the underground gas storage cavern is in a stable state; If the safety factor is less than or equal to 1, it is judged that the underground gas storage cavern is in an unstable state.

5. A device for determining the stability of initial support of a cavern of a compressed air energy storage underground gas storage, characterized in that, It comprises: A first drawing module is used to calculate the mathematical relationship between the radial displacement of the free surface of the surrounding rock and the supporting force in combination with the swelling force and softening property of the hydrophilic surrounding rock of the underground gas storage cavern, and to draw a surrounding rock response curve in the humidification process; A second drawing module is used to obtain the supporting parameters of the underground gas storage cavern, and to calculate and draw a supporting structure characteristic curve according to the supporting parameters; An obtaining module is used to determine the coordinates of the intersection point of the surrounding rock response curve and the supporting structure characteristic curve, and to obtain the balanced supporting force when the hydrophilic surrounding rock and the support are balanced according to the coordinates of the intersection point; A calculation module is used to calculate the safety factor of the underground gas storage cavern according to the balanced supporting force and the limit supporting force of the combined supporting structure; A judgment module is used to judge the stability state of the underground gas storage cavern according to the safety factor; The first drawing module calculates the mathematical relationship between the radial displacement of the free surface of the surrounding rock and the supporting force according to the following formula: ； ； wherein R0 is the chamber radius, P0 is the ground stress, P s is the support force, R P is the plastic deformation zone of the surrounding rock, is the radial displacement at the free surface of the surrounding rock, is the cohesion of the surrounding rock, is the internal friction angle of the surrounding rock, is the elastic modulus of the surrounding rock, is the Poisson's ratio of the surrounding rock, is the radial stress at the elastic-plastic interface of the surrounding rock, is the swelling pressure of the surrounding rock; wherein ; ； ； ； In the formula, is the expansion force when the water content of the surrounding rock is , and are the initial water content of the surrounding rock and the final water content of the saturated surrounding rock, respectively, is the final water content of the surrounding rock is the corresponding expansion force, , , and are the first to fourth coefficients, respectively.

6. The apparatus according to claim 5, wherein the apparatus is characterized by: The second drawing module is specifically used for: calculating support forces of each support unit of the combined support structure of the surrounding rock according to a support unit characteristic equation of the surrounding rock, the support forces of each support unit including maximum support forces of shotcrete and maximum support forces of anchor rods; obtaining a limit support force and a limit deformation of the combined support structure according to the support forces of each support unit; obtaining an overall rigidity of the combined support structure according to the limit support force and the limit deformation of the combined support structure; calculating a displacement of a free surface at a support starting position; drawing a support structure characteristic curve according to the limit support force, the overall rigidity and the displacement of the free surface at the support starting position.

7. The apparatus according to claim 5, wherein the apparatus is characterized by: The calculation module specifically calculates the safety factor of the underground gas storage cavern according to the following formula: ； wherein, is the safety factor, is the limit support force, is the balance support force.

8. The apparatus according to claim 5, wherein the apparatus is characterized by: The judgment module is specifically used for: judging whether the safety factor is greater than 1; if the safety factor is greater than 1, judging that the underground gas storage cavern is in a stable state; if the safety factor is less than or equal to 1, judging that the underground gas storage cavern is in a non-stable state.

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