Expansion sliding type steel frame of compressed air energy storage underground gas storage and design method thereof

Abstract

The present application relates to the field of compressed air energy storage, and more particularly to a compressed air energy storage underground gas storage expansion sliding steel frame and a design method thereof.The compressed air energy storage underground gas storage expansion sliding steel frame is formed by connecting a plurality of arc-shaped steel pipe segments, two adjacent steel pipe segments are a first steel pipe and a second steel pipe respectively, and the first steel pipe and the second steel pipe are connected by a steel frame joint.The present application provides a steel frame joint, an underground gas storage expandable sliding steel frame and a design method thereof.The underground gas storage expandable sliding steel frame can adapt to the large expansion deformation requirement of the soft surrounding rock gas storage, can reduce the damage of the supporting structure under the action of internal pressure, and can safely bear the surrounding rock pressure during the maintenance stage of the chamber.

Description

Technical Field

[0001] This invention relates to the field of compressed air energy storage. More specifically, this invention relates to an expansion sliding steel frame for an underground compressed air energy storage facility and its design method. Background Technology

[0002] Against the backdrop of a global energy transition towards cleaner energy sources, compressed air energy storage (CAES) technology has become a key technology supporting the large-scale consumption of renewable energy due to its advantages such as large scale, low cost, and long lifespan. As the core gas storage unit of a CAES system, underground gas storage facilities need to operate stably for extended periods under complex conditions including high-pressure gas, alternating circulating temperatures, and surrounding rock deformation. The reliability of their support structure directly affects operational safety. Underground gas storage facilities are generally located in surrounding rock with good geological conditions, where the elastic deformation capacity of the support structure can generally match the deformation of the surrounding rock, eliminating the need for telescopic supports. However, when geological conditions are poor, to fully utilize the strength of the surrounding rock to resist high gas pressure, the surrounding rock needs to undergo significant expansion deformation, and the corresponding support structure should also have a large expansion deformation capacity. Currently, tunnels in transportation and energy sectors experience large deformations in high-stress soft rock sections, which are generally addressed using retractable support structures, but these lack the ability to cope with expansion deformation.

[0003] Existing gas storage support structures generally suffer from two major technical defects: First, during high-pressure gas filling and discharging cycles, the support structure undergoes expansion and contraction due to changes in internal pressure. Since the steel frame joints lack expansion devices, the steel frame cannot adapt to large deformations when the surrounding rock conditions are poor or the surrounding local strata are weak. Second, if the surrounding rock and support structure are damaged during the gas storage stage, the large pressure from the surrounding rock acting on the damaged support structure during the cavern maintenance stage may cause the cavern to collapse. Summary of the Invention

[0004] The purpose of this invention is to provide a steel frame joint, an expandable sliding steel frame for underground gas storage, and its design method. The expandable sliding steel frame for underground gas storage can adapt to the large expansion deformation requirements of gas storage in soft surrounding rock, reduce the damage to the support structure under internal pressure, and safely withstand the surrounding rock pressure during the maintenance phase of the chamber.

[0005] To achieve these objectives and other advantages according to the present invention, an expansion sliding steel frame for an underground compressed air energy storage facility is provided, comprising multiple arc-shaped steel pipe segments connected in series, wherein two adjacent steel pipe segments are respectively a first steel pipe and a second steel pipe, and the first and second steel pipes are connected by a steel frame joint, the steel frame joint comprising:

[0006] A connecting seat is connected to one end of a second steel pipe. The connecting seat has a cavity, and a partition is provided in the cavity to divide the cavity into two independent sub-cavities along the axial direction of the second steel pipe. The connecting seat has a first annular groove corresponding to the first steel pipe, and the partition has a second annular groove corresponding to the first steel pipe. The first steel pipe passes through the first annular groove and the second annular groove in sequence and can slide relative to the connecting seat along its axial direction.

[0007] Multiple movable pin racks are evenly distributed circumferentially on the inner side of the portion of the first steel pipe located in the cavity. The movable pin racks are divided into two sections and are respectively disposed in the two sub-cavities.

[0008] Multiple fixed pin racks are provided, which correspond one-to-one with the number of movable pin racks. The fixed pin racks are divided into two sections and are respectively set in the two sub-cavities. The movable pin racks can mesh with the corresponding fixed pin racks on part of their sliding trajectory.

[0009] Two elastic rings are respectively disposed in the two sub-cavities. The elastic rings are sleeved on the steel pipe and slide against the side wall of the cavity.

[0010] Furthermore, in the aforementioned steel frame joint, the connecting seat includes:

[0011] Outerwear;

[0012] The inner sleeve is coaxially disposed inside the outer sleeve, forming the cavity between them. The partition is an annular plate and is connected to the outer sleeve and the inner sleeve respectively. The fixed pin rack is disposed on the outer side of the inner sleeve. The elastic ring slides against the inner side of the outer sleeve. The two ends of the outer sleeve and the inner sleeve are connected by a first connecting plate and a second connecting plate respectively. The first connecting plate is provided with the annular groove.

[0013] Furthermore, in the steel frame joint, the movable pin rack includes multiple rows of shear pins spaced apart along the axial direction of the first steel pipe, and each row of shear pins includes multiple shear pins spaced apart along the circumference of the first steel pipe.

[0014] Furthermore, in the steel frame joint, the number of movable pin racks provided on the first steel pipe is even, and two movable pin racks symmetrically arranged along the axial direction of the first steel pipe form a group, and the multiple rows of shear pins of two adjacent groups of movable pin racks are staggered along the radial direction of the first steel pipe.

[0015] Furthermore, in the aforementioned steel frame joint, a reinforcing mesh is provided inside the steel pipe segment, and the reinforcing mesh is welded to the corresponding steel pipe segment and the steel frame joint respectively.

[0016] The present invention also provides a design method for the expansion sliding steel frame of the above-mentioned underground compressed air energy storage facility, comprising the following steps:

[0017] S1. Obtain the parameters of the underground gas storage and the mechanical parameters of the surrounding rock. Using the stratigraphic structure method, simulate the gas filling and releasing cycle of the gas storage, calculate the deformation of the surrounding rock at different spatial locations around the gas storage to obtain the displacement range of the gas storage after the cycle stabilizes, as well as the plastic zone or damage zone of the surrounding rock formed by the cyclic load.

[0018] S2. Based on the plastic zone or damaged zone of the surrounding rock calculated in S1, calculate the surrounding rock pressure P acting on the support structure when the gas storage tank is under maintenance, that is, when the internal gas pressure is approximately zero.

[0019] S3. Based on the displacement range of the gas storage tank after cyclic stabilization calculated in S1, and combined with the functional requirements of the support structure and the material performance limits, determine the number of steel pipe segments n and the maximum allowable safe expansion. and the maximum allowable safe slippage ;

[0020] S4. Establish a mechanical model of the steel frame structure. Apply the surrounding rock pressure of the support structure calculated in S2 as an external load to the mechanical model of the steel frame structure. Calculate the internal forces acting on the joints of the steel frame under maintenance conditions. Considering the safety factor K and material strength parameters, determine the minimum shear bearing capacity that the steel frame joints must meet. ;

[0021] S5. Determine the allowable expansion amount of the steel frame joint. Design allowable slip and shear bearing capacity ,in , And based on the design allowable expansion amount Design allowable slip and shear bearing capacity Determine the number and size of the movable pin racks in the steel frame joint.

[0022] Furthermore, in the design method of the expandable sliding steel frame for the compressed air energy storage underground gas storage facility, step S3 determines the number of steel pipe segments n and the maximum allowable safe expansion amount. and the maximum allowable safe slippage Specifically:

[0023] S3.1. Based on the surrounding rock deformation at different spatial locations around the gas storage tank calculated in S1, determine the number of steel frame joints; simultaneously, divide the tunnel perimeter into equal blocks, determine the deformation of each block, and select the largest of these blocks as the maximum allowable safe expansion of the steel frame joints. ;

[0024] S3.2, Maximum permissible safe slippage The calculation method is as follows:

[0025] (1)

[0026] in, This represents the minimum displacement of the gas storage tank after the cycle stabilizes. This represents the maximum displacement of the gas storage tank after the cycle stabilizes. The safety factor for the expansion of the steel frame joint; To increase the safety factor for the total slip.

[0027] Furthermore, in the design method of the expanded sliding steel frame for the compressed air energy storage underground gas storage facility, the number and dimensions of the movable pin racks in the steel frame joint in step S5 are specifically as follows:

[0028] The sum of the shear cross-sectional areas of all movable pin racks on the steel pipe segment must satisfy the following formula (2):

[0029] (2)

[0030] in, This is the sum of the shear cross-sectional areas of all movable pin racks on the steel pipe segment; The shear yield strength of the material for the movable pin rack; This is the shear safety factor.

[0031] Furthermore, in the design method of the expanded sliding steel frame for the compressed air energy storage underground gas storage facility, the movable pin rack includes multiple shear pins, and the shear cross-section of the shear pin is square. The calculation method for the sum of the shear cross-sectional areas of all movable pin racks on the steel pipe segment is as follows:

[0032] (3)

[0033] Where m is the total number of shear pins on the steel pipe segment; h is the width of the shear pin; h is the height of the shear pin, and the maximum allowable safe expansion of the steel frame joint design determined in S3 is an integer multiple of h.

[0034] The beneficial effects of this invention are:

[0035] 1. The expandable sliding steel frame provided by this invention can expand within the displacement range from the initial state to the lower limit gas pressure of the gas storage, effectively supporting the surrounding rock and preventing the surrounding rock from loosening; it can freely slide within the displacement range corresponding to the upper and lower limit internal pressure of the gas storage, avoiding tensile damage to the steel frame during expansion and contraction; when the gas storage is in the venting or maintenance condition, the steel frame can remain in the expanded state, limiting the deformation and damage of the surrounding rock, and bearing the pressure of the surrounding rock to ensure the safety of the gas storage.

[0036] 2. The design method of the expandable sliding steel frame for underground gas storage of the present invention has a clear logic and well-defined steps, has good engineering applicability, and is easy for technicians to implement and promote.

[0037] Other advantages, objectives and features of the present invention will become apparent in part from the following description, and in part from those skilled in the art through study and practice of the invention. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of the steel frame joint in its initial state according to an embodiment of the present invention;

[0039] Figure 2 This is a schematic diagram of the steel frame joint in the expanded state in an embodiment of the present invention;

[0040] Figure 3 This is an unfolded view of the first steel pipe in an embodiment of the present invention;

[0041] Figure 4 This is an unfolded view of the first steel pipe in an embodiment of the present invention;

[0042] Figure 5 This is a schematic diagram of the expandable sliding steel frame of the underground gas storage facility described in this invention;

[0043] Figure 6 This is a schematic diagram of the underground gas storage facility described in this invention;

[0044] Figure 7 This is a design flowchart of the expandable sliding steel frame of the underground gas storage facility described in this invention.

[0045] The reference numerals in the attached figures are as follows:

[0046] 1. First steel pipe; 2. Second steel pipe; 3. Partition plate; 4. Sub-cavity; 5. Movable pin rack; 6. Fixed pin rack; 7. Elastic ring; 8. Outer sleeve; 9. Inner sleeve; 10. First connecting plate; 11. Second connecting plate connection; 12. Shear pin; 13. Steel pipe segment; 14. Steel frame joint; 15. Reinforcing mesh; 16. Sealing steel plate; 17. Slip layer; 18. Concrete support layer; 19. Surrounding rock; 20. Reinforcing mesh covering. Detailed Implementation

[0047] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the embodiments of this application, so that those skilled in the art can implement them based on the description. Obviously, the described embodiments are some embodiments of this application, but not all embodiments.

[0048] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0049] like Figures 1-4 As shown, an embodiment of the present invention provides a steel frame joint for connecting a first steel pipe 1 and a second steel pipe 2, comprising:

[0050] A connecting seat is connected to one end of the second steel pipe 2. The connecting seat has a cavity, and a partition 3 is provided in the cavity to divide the cavity into two independent sub-cavities 4 along the axial direction of the second steel pipe 2. The connecting seat has a first annular groove corresponding to the first steel pipe 1, and the partition 3 has a second annular groove corresponding to the first steel pipe 1. The first steel pipe 1 passes through the first annular groove and the second annular groove in sequence and can slide relative to the connecting seat along its axial direction. The second steel pipe 2 slides and fits against the inner walls of the first annular groove and the second annular groove to ensure a sealed connection between the second steel pipe 2 and the connecting seat.

[0051] Multiple movable pin racks 5 are evenly distributed circumferentially on the inner side of the portion of the first steel pipe 1 located in the cavity. The movable pin racks 5 are divided into two sections and are respectively disposed in the two sub-cavities 4.

[0052] Multiple fixed pin racks 6 are provided, which correspond one-to-one with the number of movable pin racks 5. The fixed pin racks 6 are divided into two sections and are respectively set in the two sub-cavities 4. The movable pin racks 5 can mesh with the corresponding fixed pin racks 6 on part of their sliding trajectory.

[0053] Two elastic rings 7 are respectively disposed in the two sub-cavities 4. The elastic rings 7 are sleeved on the steel pipe and slide against the side wall of the cavity.

[0054] In this embodiment, such as Figure 1 and Figure 2As shown, in the two sub-cavities 4, multiple fixed pin racks 6 are provided along the axial direction of the first steel pipe 1. The fixed pin racks 6 cannot completely cover the sub-cavities 4 in the axial direction of the first steel pipe 1. When the first steel pipe 1 slides along its axial direction in the connecting seat, the movable pin rack 5 can engage with the corresponding fixed pin rack 6, or slide in the area of ​​the sub-cavities 4 that the fixed pin racks 6 cannot cover. The part of the sub-cavities 4 covered by the fixed pin racks 6 forms an expansion section, and the remaining part is a sliding section.

[0055] In the initial state, such as Figure 1 As shown, at this time, the movable pin rack 5 and the fixed pin rack 6 are engaged at the end furthest from the annular groove. Under the action of external force, when the first steel pipe 1 and the second steel pipe 2 move away from each other, as... Figure 2 As shown, in the expansion section, the first steel pipe 1 and the connecting seat undergo an opening-type misalignment. The fixed shear pin 12 on the connecting seat compresses the movable shear pin 12, causing radial deformation. The elastic ring 7 is compressed by the second steel pipe 2. The fixed shear pin 12 and the movable pin rack 5 can move relative to each other, releasing the fixation between the second steel pipe 2 and the connecting seat. After the fixed shear pin 12 passes, the movable shear pin 12 rebounds and interlocks with the fixed shear pin 12. Until the movable pin rack 5 separates from the fixed pin rack 6, it enters the sliding section, where the first steel pipe 1 can slide relative to the connecting seat.

[0056] Preferably, in another embodiment of the present invention, the connecting seat includes:

[0057] 8mm outer sleeve;

[0058] The inner sleeve 9 is coaxially disposed inside the outer sleeve 8, forming the cavity between them. The partition 3 is an annular plate and is connected to the outer sleeve 8 and the inner sleeve 9 respectively. The fixed pin rack 6 is disposed on the outside of the inner sleeve 9. The elastic ring 7 slides against the inner side of the outer sleeve 8. The two ends of the outer sleeve 8 and the inner sleeve 9 are connected by a first connecting plate 10 and a second connecting plate 11 respectively. The first connecting plate 10 is provided with the annular groove.

[0059] In this embodiment, the outer sleeve 8 and the inner sleeve 9 are coaxially arranged and together with the two connecting plates form a cavity. The partition 3 divides the cavity into two sub-cavities 4, and the two sub-cavities 4 are of equal height.

[0060] Preferably, as another embodiment of the present invention, the movable pin rack 5 includes multiple rows of shear pins 12 spaced apart along the axial direction of the first steel pipe 1, and each row of shear pins 12 includes multiple shear pins 12 spaced apart along the circumference of the first steel pipe 1.

[0061] In this embodiment, the movable pin rack is made of multiple shear pins 12, which are evenly distributed. For example... Figure 1and Figure 2 As shown, a hole is made in the first steel pipe 1, and the shear pin 12 is passed through the hole and welded to the first steel pipe 1. The hole will weaken the load-bearing capacity of the first steel pipe 1. Therefore, it is necessary to appropriately thicken the wall of the first steel pipe 1.

[0062] Preferably, in another embodiment of the present invention, the number of movable pin racks 5 provided on the first steel pipe 1 is even, and two movable pin racks 5 arranged symmetrically along the axial direction of the first steel pipe 1 form a group, and the multiple rows of shear pins 12 of the two adjacent groups of movable pin racks 5 are arranged radially staggered along the first steel pipe 1.

[0063] In this embodiment, to ensure uniform force distribution when the first steel pipe is connected to the connecting seat, the movable pin racks 5 are arranged in pairs, with the two movable pin racks 5 in the same pair symmetrically arranged along the axial direction of the first steel pipe 1. The movable pin racks 5 are generally arranged in 2-4 groups. Figure 3 As shown, the movable pin racks 5 are configured in two groups, with a total of 42 shear pins 12. In the first group, the two movable pin racks 5 are spaced apart with four rows of shear pins 12, three pins per row. In the second group, the two movable pin racks 5 are spaced apart with three rows of shear pins 12, three pins per row. The multiple rows of shear pins 12 in the first and second groups are staggered. Figure 4 As shown, the movable pin racks 5 are configured in 3 groups, with a total of 54 shear pins 12. In the first group, the two movable pin racks 5 are arranged with 3 rows of shear pins 12 spaced apart, with 3 shear pins 12 in each row; in the second group, the two movable pin racks 5 are arranged with 3 rows of shear pins 12 spaced apart, with 3 shear pins 12 in each row; and in the third group, the two movable pin racks 5 are arranged with 3 rows of shear pins 12 spaced apart, with 3 shear pins 12 in each row. The multiple rows of shear pins 12 in the first, second, and third groups are staggered.

[0064] like Figures 5-6 As shown, the present invention also provides an expandable sliding steel frame for an underground gas storage facility, which is composed of multiple arc-shaped steel pipe segments 13 connected in series, and two adjacent steel pipe segments 13 are connected by a steel frame joint 14 as described in any of the above claims.

[0065] In this embodiment, although the steel pipe segment 13 is arc-shaped, its size is relatively large, and both ends can be treated as round pipes. A connecting seat is provided at one end of the steel pipe segment 13, and a movable pin rack 5 is provided at the other end. When two adjacent steel pipe segments 13 are connected in series, they serve as the first steel pipe 1 and the second steel pipe 2, respectively, and are connected by a steel frame joint 14. After the steel pipe segments are connected by the steel frame joint 14, the perimeter of the expandable steel frame can be adjusted within a certain range. Under high-pressure inflation conditions, it can effectively adapt to the circumferential expansion deformation of the support structure. Under conditions of venting and gas storage tank maintenance (without internal pressure), it can withstand the pressure generated by the surrounding rock in the damaged area. The connecting seat, movable pin rack 5, and fixed pin rack 6 can be made of materials with excellent fatigue resistance, which significantly improves the stability and reliability of the structure throughout its entire life cycle.

[0066] like Figure 6 As shown, the excavation section of the underground gas storage facility, from the inside out, consists of a sealing steel plate 16, a sliding layer 17, a concrete support layer 18, and surrounding rock 19. The expandable steel frame is located within the concrete support layer. Simultaneously, a reinforcing mesh 20 is overlapped at the steel pipe joints to ensure that the shotcrete on the concrete support layer does not fall off.

[0067] like Figure 7 As shown, the present invention also provides a design method for the expandable sliding steel frame of the above-mentioned underground gas storage facility, comprising the following steps:

[0068] S1. Obtain the parameters of the underground gas storage and the mechanical parameters of the surrounding rock. Using the stratigraphic structure method, simulate the gas filling and releasing cycle of the gas storage, calculate the deformation of the surrounding rock at different spatial locations around the gas storage to obtain the displacement range of the gas storage after the cycle stabilizes, as well as the plastic zone or damage zone of the surrounding rock formed by the cyclic load.

[0069] S2. Based on the plastic zone or damaged zone of the surrounding rock calculated in S1, calculate the surrounding rock pressure P acting on the support structure when the gas storage tank is under maintenance, that is, when the internal gas pressure is approximately zero.

[0070] S3. Based on the displacement range of the gas storage tank after cyclic stabilization calculated in S1, and combined with the functional requirements of the support structure and the material performance limits, determine the number n of steel pipe segments 13 and the maximum allowable safe expansion. and the maximum allowable safe slippage Specifically:

[0071] S3.1. Based on the surrounding rock deformation at different spatial locations around the gas storage tank calculated in S1, determine the number of steel frame joints 14; simultaneously, divide the tunnel perimeter into equal blocks, determine the deformation of each block, and select the largest one as the maximum allowable safe expansion of the steel frame joint 14. ;

[0072] S3.2, Maximum permissible safe slippage The calculation method is as follows:

[0073] (1)

[0074] in, This represents the minimum displacement of the gas storage tank after the cycle stabilizes. This represents the maximum displacement of the gas storage tank after the cycle stabilizes. The safety factor for the expansion of steel frame joint 14; To increase the safety factor for the total slip.

[0075] S4. Establish a mechanical model of the steel frame structure. Apply the surrounding rock pressure of the support structure calculated in S2 as an external load to the mechanical model of the steel frame structure. Calculate the internal forces acting on the steel frame joint 14 under maintenance conditions. The internal forces are the shear force components perpendicular to the joint contact surface that the steel frame joint 14 needs to transmit. Considering the safety factor K and material strength parameters, determine the minimum shear bearing capacity that the steel frame joint 14 must satisfy. ;

[0076] S5. Determine the allowable expansion amount of the steel frame joint 14. Design allowable slip and shear bearing capacity ,in , And based on the design allowable expansion amount Design allowable slip and shear bearing capacity The quantity and dimensions of the movable pin rack 5 in the steel frame joint 14 are determined as follows:

[0077] The sum of the shear cross-sectional areas of all movable pin racks 5 on steel pipe segment 13 needs to satisfy the following formula (2):

[0078] (2)

[0079] in, The sum of the shear cross-sectional areas of all movable pin racks 5 on the steel pipe segment 13; The shear yield strength of the material for the movable pin rack 5; This is the shear safety factor.

[0080] Furthermore, in the design method of the expandable sliding steel frame of the underground gas storage facility, the movable pin rack 5 includes multiple shear pins 12, and the shear section of the shear pin 12 is square. The calculation method for the sum of the shear cross-sectional areas of all movable pin racks 5 on the steel pipe segment 13 is as follows:

[0081] (3)

[0082] Where m is the total number of shear pins 12 on steel pipe segment 13; h is the width of the shear pin 12; h is the height of the shear pin 12, and the maximum allowable safe expansion of the steel frame joint 14 determined in S3 is an integer multiple of h.

[0083] This invention also provides a design method for an expandable steel frame for an underground gas storage facility, comprising the following steps:

[0084] S1. Obtaining underground gas storage parameters and surrounding rock mechanical parameters: The gas storage chamber is a tunnel type, 18m in diameter, with a maximum operating internal pressure of 16MPa, a burial depth of 215m, and Class III surrounding rock. The structure consists of a 15cm concrete support layer, a 5cm mortar slip layer, and a 10mm steel plate sealing layer. The steel plate is Q420, and the joint structure uses high-strength spring steel (65Mn). The physical and mechanical parameters of the surrounding rock are: elastic modulus 8GPa, friction angle 50°, cohesion 1.5MPa, and density 2650kg / m³. 3 ;

[0085] Using the stratigraphic structure method, a numerical calculation model of the cross-section of the gas storage chamber was established. The maximum displacement of the surrounding rock of the gas storage under the above conditions was calculated to be 3.78 cm, and the maximum circumferential strain of the sealing layer steel plate was obtained to be 4.2‰.

[0086] S2. Based on the plastic zone or damaged zone of the surrounding rock calculated in S1, calculate the surrounding rock pressure P acting on the support structure when the gas storage tank is under maintenance, that is, when the internal gas pressure is approximately zero.

[0087] S3. Based on the deformation of the surrounding rock at key locations under inflation and deflation conditions calculated in S1, and considering the functional requirements of the support structure and the material performance limits, four steel frame joints 14 and four steel pipe segments 13 are set. The maximum deformation is determined at the arch crown by segmentation. At this point, the deformation at the arch crown is taken as the maximum deformation, and the maximum allowable safe expansion is designed. =4cm, designed to allow maximum safe slippage =2cm;

[0088] S4, the strength safety factor of steel frame joint 14 is 1.5. Based on the obtained surrounding rock pressure acting on the support structure, a steel pipe load structure model is established to calculate the internal forces acting on the steel pipe, and then the minimum shear bearing capacity that steel frame joint 14 must satisfy is determined. ;

[0089] S5, to meet the allowable expansion δ specified in S3 and the minimum bearing capacity F specified in S4. vminTo achieve the target, the number of shear pins 12 in the steel frame joint 14 is determined to be 42 using equations (2) and (3). The shear cross-section of the shear pin 12 is square, with dimensions (width × height) of 1.0cm × 1.2cm. The distribution of the 42 shear pins 12 is as follows: Figure 3 As shown. Based on the joint internal forces and the steel pipe material properties, the wall thickness t of the steel pipe that meets the strength and deformation requirements is calculated to be 12 mm.

[0090] The above design method has clear logic and well-defined steps, and has good engineering applicability, making it easy for technical personnel to implement and promote its application efficiently.

[0091] Furthermore, although the operations of the method of this application are described in a specific order in the accompanying drawings, this does not require or imply that these operations must be performed in that specific order, or that all the operations shown must be performed to achieve the desired result. Additionally or alternatively, certain steps may be omitted, multiple steps may be combined into one step, and / or one step may be broken down into multiple steps.

[0092] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application and are not intended to limit it. Although this application has been described in detail with reference to the embodiments, those skilled in the art should understand that modifications or equivalent substitutions to the technical solutions of this application do not depart from the spirit and scope of the technical solutions of this application, and should all be covered within the scope of the claims of this application.

Claims

1. A compressed air energy storage underground gas storage cavern expanded slip-style steel frame, characterized in that, It is composed of multiple arc-shaped steel pipe segments connected in series. Two adjacent steel pipe segments are designated as a first steel pipe and a second steel pipe, respectively. The first and second steel pipes are connected by a steel frame joint, which includes: A connecting seat is connected to one end of a second steel pipe. The connecting seat has a cavity, and a partition is provided in the cavity to divide the cavity into two independent sub-cavities along the axial direction of the second steel pipe. The connecting seat has a first annular groove corresponding to the first steel pipe, and the partition has a second annular groove corresponding to the first steel pipe. The first steel pipe passes through the first annular groove and the second annular groove in sequence and can slide relative to the connecting seat along its axial direction. Multiple movable pin racks are evenly distributed circumferentially on the inner side of the portion of the first steel pipe located in the cavity. The movable pin racks are divided into two sections and are respectively disposed in the two sub-cavities. Multiple fixed pin racks are provided, which correspond one-to-one with the number of movable pin racks. The fixed pin racks are divided into two sections and are respectively set in the two sub-cavities. The movable pin racks can mesh with the corresponding fixed pin racks on part of their sliding trajectory. Two elastic rings are respectively disposed in the two sub-cavities. The elastic rings are sleeved on the steel pipe and slide against the side wall of the cavity.

2. The dilatational sliding steel arch of compressed air energy storage underground gas storage according to claim 1, characterized in that, The connector includes: Outerwear; The inner sleeve is coaxially disposed inside the outer sleeve, forming the cavity between them. The partition is an annular plate and is connected to the outer sleeve and the inner sleeve respectively. The fixed pin rack is disposed on the outer side of the inner sleeve. The elastic ring slides against the inner side of the outer sleeve. The two ends of the outer sleeve and the inner sleeve are connected by a first connecting plate and a second connecting plate respectively. The first connecting plate is provided with the annular groove.

3. The dilatational sliding steel arch of compressed air energy storage underground gas storage according to claim 2, characterized in that, The movable pin rack includes multiple rows of shear pins spaced apart along the axial direction of the first steel pipe, and each row of shear pins includes multiple shear pins spaced apart along the circumference of the first steel pipe.

4. The compressed air energy storage underground gas storage cavern expanded slip-style steel arch of claim 3, wherein, The number of movable pin racks on the first steel pipe is even, and two movable pin racks arranged symmetrically along the axial direction of the first steel pipe form a group. The multiple rows of shear pins of two adjacent groups of movable pin racks are arranged alternately along the radial direction of the first steel pipe.

5. The dilatational sliding steel arch of compressed air energy storage underground gas storage according to claim 1, characterized in that, The steel pipe segment is equipped with a reinforcing mesh, which is welded to the corresponding steel pipe segment and steel frame joint.

6. A method of designing a compressed air energy storage underground gas storage cavern expanded slip-style steel arch according to any one of claims 1-5, characterized in that, Includes the following steps: S1. Obtain the parameters of the underground gas storage and the mechanical parameters of the surrounding rock. Using the stratigraphic structure method, simulate the gas filling and releasing cycle of the gas storage, calculate the deformation of the surrounding rock at different spatial locations around the gas storage to obtain the displacement range of the gas storage after the cycle stabilizes, as well as the plastic zone or damage zone of the surrounding rock formed by the cyclic load. S2. Based on the plastic zone or damaged zone of the surrounding rock calculated in S1, calculate the surrounding rock pressure P acting on the support structure when the gas storage tank is under maintenance, that is, when the internal gas pressure is approximately zero. S3. Based on the displacement range of the gas storage tank after cyclic stabilization calculated in S1, and combined with the functional requirements of the support structure and the material performance limits, determine the number of steel pipe segments n and the maximum allowable safe expansion. and the maximum allowable safe slippage ; S4, a steel frame structure mechanics model is established, the surrounding rock pressure of the support structure calculated in S2 is applied as an external load on the steel frame structure mechanics model, the internal force acting on the steel frame joint position under the maintenance working condition is calculated, and the minimum shear bearing capacity required by the steel frame joint is determined by considering the safety factor K and the material strength parameters ; S5, determining a design allowable expansion of the steel frame joint , a design allowable slip , and a shear capacity wherein , ; and the design allowable expansion , the design allowable slip , and the shear capacity , the number and size of the movable pin racks in the steel frame joint are determined.

7. The design method of the expanded slip-type steel arch of compressed air energy storage underground gas storage according to claim 6, characterized in that, S3 determines the number of steel pipe segments n and the maximum allowable safe expansion. and the maximum allowable safe slippage Specifically: S3.

1. Based on the surrounding rock deformation at different spatial locations around the gas storage tank calculated in S1, determine the number of steel frame joints; simultaneously, divide the tunnel perimeter into equal blocks, determine the deformation of each block, and select the largest of these blocks as the maximum allowable safe expansion of the steel frame joints. ; S3.2, Design for maximum allowable safety slip The calculation method is as follows: （1） in, This represents the minimum displacement of the gas storage tank after the cycle stabilizes. This represents the maximum displacement of the gas storage tank after the cycle stabilizes. The safety factor for the expansion of the steel frame joint; To increase the safety factor for the total slip.

8. The design method of the expanded slip-type steel arch of compressed air energy storage underground gas storage according to claim 6, characterized in that, The quantity and dimensions of the movable pin racks in the steel frame joint design in S5 are as follows: The sum of the shear cross-sectional areas of all movable pin racks on the steel pipe segment must satisfy the following formula (2): （2） wherein, is the sum of the shear cross-sectional area of all the movable pin racks on the steel pipe section; is the shear yield strength of the movable pin rack material; is the shear safety factor.

9. The design method of the expanded slip-type steel arch of compressed air energy storage underground gas storage according to claim 8, characterized in that, A movable pin rack consists of multiple shear pins, each with a square shear cross-section. The method for calculating the sum of the shear cross-sectional areas of all movable pin racks on a steel pipe segment is as follows: （3） where m is the total number of shear pins on the steel pipe section; where w is the width of the shear pin; h is the height of the shear pin, and the maximum safe expansion allowed for the design of the steel frame joint determined in S3 is an integer multiple of h.

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