A torsional deformation and air compression based energy dissipation device and its design method

Abstract

A kind of energy dissipation device based on torsional deformation and air compression and its design method, to effectively improve the energy dissipation efficiency of energy dissipation device, make its yield platform more stable, and energy dissipation component cost is lower, more convenient to replace.The energy dissipation device includes upper rotating part, metal energy dissipation component and lower fixed part;Upper rotating part includes upper connecting plate, rotating plate and upper sleeve, the lower plate surface of upper connecting plate, the upper plate surface of rotating plate are fixedly connected with ball bearing respectively, the upper sleeve with external thread structure is welded and fixed on the lower plate surface of rotating plate;Metal energy dissipation component is installed between the central part of upper connecting plate and rotating plate, and its upper part and lower part are fixedly connected with upper connecting plate and rotating plate respectively;Lower fixed part is composed of lower sleeve and lower mounting plate, the lower sleeve with internal thread structure is welded and fixed on the upper plate surface of lower mounting plate, and the internal thread structure is matched with the external thread structure of upper sleeve, and the upper sleeve and lower sleeve form screw connection.

Description

Technical Field

[0001] This invention relates to energy dissipation and vibration reduction devices for civil engineering structures, and particularly to an energy dissipation device based on torsional deformation of a metal block and air compression, and its design method. Background Technology

[0002] The construction of mountain roads, especially in high-intensity earthquake-prone areas, often encounters adverse geological conditions such as high-altitude landslides due to earthquakes and subsequent secondary disasters. Protection against high-altitude landslides typically employs methods such as hazard removal, shotcreting with mesh reinforcement, and end-of-pipe protection. In high-altitude landslide areas where hazard removal or rock mass treatment is difficult, end-of-pipe protection is a more economical, effective, and convenient approach compared to hazard removal. Currently, the mainstream end-of-pipe protection methods include reinforced concrete rigid tunnels, open tunnels, and flexible tunnels. Lightweight steel structure tunnels, as a type of flexible tunnel, have been widely used in mountain road construction. This type of protection scheme is effective in protecting sections with few, small, but high-momentum scattered rockfalls, effectively enhancing the road's disaster resistance. Furthermore, these protection schemes are all prefabricated steel structures, characterized by convenient installation and rapid construction. During construction, there is minimal disruption to existing traffic, reducing the pressure on maintaining traffic flow and strengthening the resilience of disaster-prone mountain roads, thereby improving their overall toughness. Currently, this type of flexible tunnel has been widely used in numerous highway and national / provincial trunk road projects. To broaden the applicability of this type of tunnel and reduce the impact of the tunnel structure on the substructure or bridge substructure, metal energy dissipators are used. This component acts as a safeguard for the substructure, forming a multi-stage energy dissipation system together with the cable net, dissipating energy from impacts and falling rocks, and protecting the safety of vehicles and the road structure, thereby increasing the disaster prevention capabilities of the road sections in use.

[0003] Currently, the two existing designs for energy dissipators in tunnel structures present two problems. For the straight-tube type, the yield strength is too high, resulting in a large reaction force and unsatisfactory stress on the lower structure. For the bellows type, the collapse deformation of each waveform begins sequentially, leading to an unstable yield plateau. Although the energy dissipation efficiency is significantly improved compared to the straight-tube type, it is still not high. Torsion tests on round bars show that the torque-torsion angle curve of a solid metal round bar has a stable yield plateau and high energy dissipation efficiency. Based on this energy dissipation principle, a device is developed to convert the downward impact force of the tunnel arch frame into a torsional force on a circular metal block, and to utilize the compression of air within the device for comprehensive energy dissipation. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide an energy-consuming device based on torsional deformation and air compression, so as to effectively improve the energy consumption efficiency of the energy-consuming device, make its yielding platform more stable, and make the energy-consuming components cheaper and easier to replace.

[0005] The technical solution adopted by this invention to solve its technical problem is as follows:

[0006] This invention discloses an energy-consuming device based on torsional deformation and air compression, disposed between the main structure and the lower structure of a protective structure. The device comprises an upper rotating part, a metal energy-consuming component, and a lower fixed part. The upper rotating part includes an upper connecting plate, a rotating plate, and an upper sleeve. The lower surface of the upper connecting plate and the upper surface of the rotating plate are fixedly connected to ball bearings. The upper sleeve, having an external thread structure, is welded and fixed to the lower surface of the rotating plate. The metal energy-consuming component is installed between the upper connecting plate and the central portion of the rotating plate, with its upper and lower parts fixedly connected to the upper connecting plate and the rotating plate, respectively. The lower fixed part consists of a lower sleeve and a lower mounting plate. The lower sleeve, having an internal thread structure, is welded and fixed to the upper surface of the lower mounting plate. This internal thread structure is compatible with the external thread structure of the upper sleeve, and the upper and lower sleeves form a helical connection.

[0007] The main body of the metal energy-consuming component is an energy-consuming metal rod located between the lower surface of the upper connecting plate and the upper surface of the rotating plate. The axis of the energy-consuming metal rod coincides with the axis of the upper sleeve. The upper end of the energy-consuming metal rod is welded to the upper connecting plate to form an upper mounting part, and the lower end is welded to the upper rotating plate to form a lower mounting part.

[0008] The lower end of the upper sleeve is closed, and its central part protrudes downward to form an air chamber.

[0009] Another technical problem to be solved by the present invention is to provide a design method for the above-mentioned energy-consuming device based on torsional deformation and air compression.

[0010] The method includes the following steps:

[0011] S1. Based on the design requirements of the protective structure, determine the maximum working energy dissipation capacity E, the maximum working reaction force F, and the impact force F required to start the energy dissipation device. c The calculated diameter D of the energy-dissipating device is determined based on the dimensions of the upper connecting plate and the lower mounting plate. The height range and deformation stroke range of the energy-dissipating device are determined based on the clearance requirements required for the protective structure design and the size of the main structure. The preliminary energy-dissipating stroke h is then determined. c ;

[0012] S2. Based on the maximum working reaction force F and the impact force F required to start the energy-consuming device. c The diameter D1 of the energy-consuming metal rod and the engagement pitch P of the upper and lower sleeves are determined as follows:

[0013] The maximum working reaction force F consists of two parts: one is the reaction force F required to start the energy-consuming metal rod. h Secondly, the maximum reaction force F generated by the compression of the air spring inside the sleeve. q ,Right now:

[0014] F = F h +F q (1)

[0015] The reaction force F required to start the energy-consuming metal rod is as follows. h Calculate using the following formula:

[0016]

[0017] In the formula: D is the calculated diameter of the energy-consuming device, taken as the distance from the center of the thread tooth of the energy-consuming device to the center of the circle; T P The yield torque of the energy-consuming metal rod is given by formula... Calculate τ y K represents the shear yield strength of the energy-dissipating metal rod, D1 is the diameter of the energy-dissipating metal rod; h --Conversion factor, determined based on geometric relationships. Where k f Let θ be the friction coefficient between the upper rotating part and the lower fixed part, where θ is the angle between the meshing surface of the upper rotating part and the lower fixed part and the horizontal plane. It is obtained by calculating the geometric relationship between the diameter D and the pitch P from the energy-consuming device. The geometric relationship is P=πDtanθ;

[0018] The maximum reaction force F generated by the compression of the air spring inside the sleeve above q Calculate using the following formula:

[0019]

[0020] Where: V1 is the gas volume when the energy-consuming device completes its stroke; V2 is the initial gas volume of the energy-consuming device; γ is the gas adiabatic index, which is 1.4 for air; P2 is the initial gas pressure of the energy-consuming device; K q1 The reaction force deviation coefficient caused by gas leakage and heat dissipation inside the sleeve is obtained from the dynamic impact test;

[0021] When initially determining the dimensions, the upper rotating part is taken as the cylinder, and the calculated diameter D, height, and energy-consuming stroke h of the energy-consuming device are determined accordingly. c Determine the air compression ratio Adjust the diameter D1 of the energy-consuming metal rod, and perform trial calculations on the initially proposed dimensions using formulas (1) to (3) to ensure that the maximum working reaction force F calculated by formula (1) is not greater than the design requirements of the protective structure in the project, and the reaction force F required for the energy-consuming metal rod to dissipate energy calculated by formula (2) is also determined. h Not greater than the impact force F required to start the energy-consuming device c ;

[0022] S3. After initially determining the diameter D1 of the energy-consuming metal rod and the engagement pitch P of the upper and lower sleeves, calculate the maximum working energy consumption capacity E based on the initially determined dimensions.

[0023] The maximum working energy dissipation capacity E consists of three parts, one of which is the rotational energy dissipation E provided by the rotation of the energy-dissipating metal rod. h Secondly, the frictional energy E generated by the friction between the upper rotating part and the lower fixed part. f Thirdly, the energy loss due to compression of air inside the sleeve, E q ,Right now:

[0024] E = E h +E f +E q (4)

[0025] in:

[0026]

[0027] In the formula: D1 is the diameter of the energy-consuming metal rod; τ y θ represents the shear yield strength of the energy-dissipating metal rod. p The energy-consuming angle is the angle between the upper rotating part and the lower fixed part when the energy-consuming metal rod begins to yield until the energy-consuming device completes its stroke.

[0028]

[0029] In the formula: P1 is the gas pressure when the energy-consuming device has completed its stroke, derived from the formula... Find K q2 The energy consumption deviation coefficient caused by factors such as gas leakage inside the cylinder is obtained from dynamic impact tests.

[0030] S4. Compare the maximum working energy consumption capacity E calculated in step S3 with the value required for the protective structure design. If the requirements are not met, adjust the volume compression ratio of the compressed gas in the cylinder first. The specific adjustment method is as follows:

[0031] Increase the solid part of the upper sleeve of the upper rotating part by adjusting the compressed volume of the gas at the end of the formation. Consider the safety of the upper sleeve wall thickness and whether the maximum working reaction force F exceeds the design limit. If it does not meet the requirements, the dimensions need to be re-determined and steps S2 to S4 are repeated until the design requirements are met.

[0032] S5. Verify the energy-consuming device with the determined size by dynamic impact test, and finalize the geometric and material parameters of the energy-consuming device.

[0033] The beneficial effects of this invention patent are mainly reflected in the following aspects:

[0034] 1. The energy-consuming device has a stable yielding platform, high energy consumption efficiency, and its energy-consuming components are inexpensive and easy to replace.

[0035] Second, it can be conveniently used in various flexible tunnel structures as a kind of protection for the substructure. Together with the net cable, it forms a multi-level energy dissipation system to dissipate energy from impacts and falling rocks and protect the safety of traffic and road structure, thereby increasing the disaster prevention capability of the road section and solving the safety problem of flexible tunnel structures under various structural load-bearing capacity limitations.

[0036] Third, it has a wide range of applications, and can be used in both new construction projects and the reinforcement and renovation of existing bridge piers. Attached Figure Description

[0037] This instruction manual includes the following ten figures:

[0038] Figure 1 This is a front view of an energy-consuming device based on torsional deformation and air compression according to the present invention;

[0039] Figure 2 This is a top view of an energy-consuming device based on torsional deformation and air compression according to the present invention;

[0040] Figure 3 This is a front view of a metal energy-consuming component in an energy-consuming device based on torsional deformation and air compression according to the present invention.

[0041] Figure 4 This is a top view of a metal energy-consuming component in an energy-consuming device based on torsional deformation and air compression according to the present invention.

[0042] Figure 5 This is a schematic diagram of the upper rotating part in an energy-consuming device based on torsional deformation and air compression according to the present invention.

[0043] Figure 6 It is along Figure 5 Sectional view of line AA in the middle;

[0044] Figure 7 This is a schematic diagram of the lower fixed part in an energy-consuming device based on torsional deformation and air compression according to the present invention.

[0045] Figure 8 This is a top view of the lower fixed part in an energy-consuming device based on torsional deformation and air compression according to the present invention;

[0046] Figure 9 This is a schematic diagram of the structure of an energy-consuming device based on torsional deformation and air compression in the installation state of the present invention;

[0047] Figure 10 This is a schematic diagram of the structure of an energy-consuming device based on torsional deformation and air compression under energy-consuming conditions according to the present invention.

[0048] The figure shows the names of the main components and their corresponding markings: upper connecting plate 11, ball bearing 12, rotating plate 13, upper sleeve 14, upper mounting hole 15, lower sleeve 21, lower mounting plate 22, lower mounting hole 23, energy-consuming metal rod 30, first upper polygonal boss 31, second upper polygonal boss 32, and lower polygonal boss 33. Detailed Implementation

[0049] The present invention will be further described below with reference to the accompanying drawings.

[0050] Reference Figures 1 to 8 This invention discloses an energy-consuming device based on torsional deformation and air compression, disposed between the main structure and the lower structure of a protective structure. The energy-consuming device includes an upper rotating part, a metal energy-consuming component, and a lower fixed part. The upper rotating part includes an upper connecting plate 11, a rotating plate 13, and an upper sleeve 14. The lower surface of the upper connecting plate 11 and the upper surface of the rotating plate 13 are respectively fixedly connected to ball bearings 12. The upper sleeve 14, having an external thread structure, is welded and fixed to the lower surface of the rotating plate 13. The metal energy-consuming component is installed between the central portion of the upper connecting plate 11 and the rotating plate 13, with its upper and lower parts respectively fixedly connected to the upper connecting plate 11 and the rotating plate 13. The lower fixed part consists of a lower sleeve 21 and a lower mounting plate 22. The lower sleeve 21, having an internal thread structure, is welded and fixed to the upper surface of the lower mounting plate 22. This internal thread structure is compatible with the external thread structure of the upper sleeve 14, and the upper sleeve 14 and the lower sleeve 21 form a helical connection.

[0051] When the tunnel is subjected to the impact of falling rocks, the main structure of the tunnel transmits the impact force to the energy dissipation device. The upper rotating part tends to rotate under the action of the downward impact force. When the impact force is greater than the force required to cause the metal energy dissipation component to torsionally yield, the energy dissipation device starts to work and generates energy dissipation. The energy dissipation of the energy dissipation device mainly comes from the deformation energy dissipation of the metal energy dissipation component, the friction energy dissipation generated by the thread engagement, and the energy dissipation of the compressed air inside the sleeve.

[0052] Reference Figure 3 and Figure 4 The main body of the metal energy-consuming component is an energy-consuming metal rod 30 located between the lower surface of the upper connecting plate 11 and the upper surface of the rotating plate 13. The axis of the energy-consuming metal rod 30 coincides with the axis of the upper sleeve 14. The upper end of the energy-consuming metal rod 30 is welded to the upper connecting plate 11 to form an upper mounting part, and the lower end is welded to the upper rotating plate 13 to form a lower mounting part. That is, the metal energy-consuming component adopts a replaceable design. After one energy-consuming deformation, the metal energy-consuming component can be removed and the energy-consuming device reset. Then, a new metal energy-consuming component can be inserted to restore the energy-consuming device to its initial energy-consuming capacity.

[0053] Reference Figure 5 The lower end of the upper sleeve 14 is closed, and its central portion protrudes downward to form an air chamber 15. (Refer to...) Figure 10 The volume of the gas chamber is the gas volume 15V1 when the energy-consuming device completes its stroke.

[0054] Reference Figure 3 and Figure 5 The upper mounting part is composed of a first upper polygonal boss 31 and a second upper polygonal boss 32 stacked together. The size of the second upper polygonal boss 32, which is located on top, is larger than the size of the first upper polygonal boss 31. A double-layer polygonal mounting hole adapted to it is opened in the center of the upper connecting plate 11. The lower mounting part is a lower polygonal boss 33. The size of the lower polygonal boss 33 is equal to or smaller than the size of the first upper polygonal boss 31. A polygonal mounting hole adapted to it is opened in the center of the rotating plate 13.

[0055] Reference Figure 6 The upper connecting plate 11 has longitudinally and laterally spaced upper mounting holes 15 for connecting with the main protective structure. (Refer to...) Figure 8 The lower mounting plate 22 has longitudinally and laterally spaced lower mounting holes 23 for connecting with the lower protective structure.

[0056] This invention effectively improves the energy consumption efficiency of energy-consuming devices, making their yield plateau more stable. Taking an energy-consuming device with a maximum reaction force of 600kN as an example for comparison, the existing bellows-type metal energy-consuming device (height 350mm, diameter 270mm, waveform R25, thickness 5mm) has a maximum reaction force of approximately 600kN and a maximum energy consumption of approximately 100kJ. After adopting this energy-consuming device (height 350mm, diameter 300mm, energy-consuming block diameter 97mm, energy-consuming stroke 200mm, upper and lower interlocking thread pitch 300mm), under the condition of ensuring good airtightness, the maximum energy consumption can reach 180kJ according to theoretical formulas, increasing energy consumption by 80%. Furthermore, only the energy-consuming metal rod is damaged after energy consumption; the energy-consuming metal component can be replaced, the device reset, and the energy-consuming device can continue to be used.

[0057] The present invention discloses a design method for an energy-consuming device based on torsional deformation and air compression, comprising the following steps:

[0058] S1. Based on the design requirements of the protective structure, determine the maximum working energy dissipation capacity E, the maximum working reaction force F, and the impact force F required to start the energy dissipation device. c The calculated diameter D of the energy-consuming device is determined based on the dimensions of the upper connecting plate (11) and the lower mounting plate (22). The height range and deformation stroke range of the energy-consuming device are determined based on the clearance requirements required for the protective structure design and the size of the main structure. Then, the energy-consuming stroke h is initially determined. c ;

[0059] S2. Based on the maximum working reaction force F and the impact force F required to start the energy-consuming device. cThe diameter D1 of the energy-consuming metal rod, the engagement pitch P of the upper sleeve (14) and the lower sleeve (21) are determined as follows:

[0060] The maximum working reaction force F consists of two parts: one is the reaction force F required to start the energy-consuming metal rod. h Secondly, the maximum reaction force F generated by the compression of the air spring inside the sleeve. q ,Right now:

[0061] F = F h +F q (4)

[0062] The reaction force F required to start the energy-consuming metal rod is as follows. h Calculate using the following formula:

[0063]

[0064] In the formula: D is the calculated diameter of the energy-consuming device, taken as the distance from the center of the thread tooth of the energy-consuming device to the center of the circle; T P The yield torque of the energy-consuming metal rod is given by formula... Calculate τ y K represents the shear yield strength of the energy-dissipating metal rod, D1 is the diameter of the energy-dissipating metal rod; h --Conversion factor, determined based on geometric relationships. Where k f Let θ be the friction coefficient between the upper rotating part and the lower fixed part, where θ is the angle between the meshing surface of the upper rotating part and the lower fixed part and the horizontal plane. It is obtained by calculating the geometric relationship between the diameter D and the pitch P from the energy-consuming device. The geometric relationship is P=πDtanθ;

[0065] The maximum reaction force F generated by the compression of the air spring inside the sleeve above q Calculate using the following formula:

[0066]

[0067] Where: V1 is the gas volume when the energy-consuming device completes its stroke; V2 is the initial gas volume of the energy-consuming device; γ is the gas adiabatic index, which is 1.4 for air; P2 is the initial gas pressure of the energy-consuming device; K q1 The reaction force deviation coefficient caused by gas leakage and heat dissipation inside the sleeve is obtained from the dynamic impact test;

[0068] When initially determining the dimensions, the upper rotating part is taken as the cylinder, and the calculated diameter D, height, and energy-consuming stroke h of the energy-consuming device are determined accordingly. c Determine the air compression ratio Adjust the diameter D1 of the energy-consuming metal rod, and perform trial calculations on the initially proposed dimensions using formulas (1) to (3) to ensure that the maximum working reaction force F calculated by formula (1) is not greater than the design requirements of the protective structure in the project, and the reaction force F required for the energy-consuming metal rod to dissipate energy calculated by formula (2) is also determined. h Not greater than the impact force F required to start the energy-consuming device c ;

[0069] S3. After initially determining the diameter D1 of the energy-consuming metal rod, the engagement pitch P of the upper sleeve (14) and the lower sleeve (21), calculate the maximum working energy consumption capacity E based on the initially determined dimensions.

[0070] The maximum working energy dissipation capacity E consists of three parts, one of which is the rotational energy dissipation E provided by the rotation of the energy-dissipating metal rod. h Secondly, the frictional energy E generated by the friction between the upper rotating part and the lower fixed part. f Thirdly, the energy loss due to compression of air inside the sleeve, E q ,Right now:

[0071] E = E h +E f +E q (4)

[0072] in:

[0073]

[0074] In the formula: D1 is the diameter of the energy-consuming metal rod; τ y θ represents the shear yield strength of the energy-dissipating metal rod. p The energy-consuming angle is the angle between the upper rotating part and the lower fixed part when the energy-consuming metal rod begins to yield until the energy-consuming device completes its stroke.

[0075]

[0076] In the formula: P1 is the gas pressure when the energy-consuming device has completed its stroke, derived from the formula... Find K q2 The energy consumption deviation coefficient caused by factors such as gas leakage inside the cylinder is obtained from dynamic impact tests.

[0077] S4. Compare the maximum working energy consumption capacity E calculated in step S3 with the value required for the protective structure design. If the requirements are not met, adjust the volume compression ratio of the compressed gas in the cylinder first. The specific adjustment method is as follows:

[0078] Increase the solid part of the upper sleeve of the upper rotating part by adjusting the compressed volume of the gas at the end of the formation. Consider the safety of the upper sleeve wall thickness and whether the maximum working reaction force F exceeds the design limit. If it does not meet the requirements, the dimensions need to be re-determined and steps S2 to S4 are repeated until the design requirements are met.

[0079] S5. Verify the energy-consuming device with the determined size by dynamic impact test, and finalize the geometric and material parameters of the energy-consuming device.

Claims

1. A twist deformation and air compression based energy dissipation device provided between a main structure and a lower structure of a protective structure, characterized in that: The energy dissipation device comprises an upper rotating part, a metal energy dissipation component and a lower fixing part; the upper rotating part comprises an upper connecting plate (11), a rotating plate (13) and an upper sleeve (14), the lower plate surface of the upper connecting plate (11) and the upper plate surface of the rotating plate (13) are fixedly connected with a ball bearing (12) respectively, and the upper sleeve (14) with an external thread structure is welded and fixed on the lower plate surface of the rotating plate (13); the metal energy dissipation component is installed between the central parts of the upper connecting plate (11) and the rotating plate (13), and the upper part and the lower part thereof are fixedly connected with the upper connecting plate (11) and the rotating plate (13) respectively; the lower fixing part is composed of a lower sleeve (21) and a lower mounting plate (22), the lower sleeve (21) with an internal thread structure is welded and fixed on the upper plate surface of the lower mounting plate (22), and the internal thread structure is matched with the external thread structure of the upper sleeve (14), and the upper sleeve (14) and the lower sleeve (21) are screw-connected; the main body of the metal energy dissipation component is an energy dissipation metal rod (30) located between the lower plate surface of the upper connecting plate (11) and the upper plate surface of the rotating plate (13), and the axis of the energy dissipation metal rod (30) is coincided with the axis of the upper sleeve (14); the upper end of the energy dissipation metal rod (30) is welded to form an upper mounting part inserted with the upper connecting plate (11), and the lower end is welded to form a lower mounting part inserted with the upper rotating plate (13); the lower end of the upper sleeve (14) is closed, and the central part thereof is protruded downward to form an air chamber (15).

2. A twist deformation and air compression based energy dissipation device as claimed in claim 1, wherein: the first upper polygonal boss (31) and the second upper polygonal boss (32) of the upper mounting part are stacked, the size of the second upper polygonal boss (32) located on the upper side is greater than the size of the first upper polygonal boss (31), and a double-layer polygonal mounting hole matched with the first upper polygonal boss (31) is formed in the central part of the upper connecting plate (11); the lower mounting part is a lower polygonal boss (33), and the size of the lower polygonal boss (33) is equal to or less than the size of the first upper polygonal boss (31), and a polygonal mounting hole matched with the lower polygonal boss (33) is formed in the central part of the rotating plate (13).

3. A twist deformation and air compression based energy dissipation device as claimed in claim 1, wherein: the upper mounting holes (15) for connecting with the main body structure of the protective structure are arranged on the plate surface of the upper connecting plate (11) in longitudinal and transverse directions; and the lower mounting holes (23) for connecting with the lower structure of the protective structure are arranged on the plate surface of the lower mounting plate (22) in longitudinal and transverse directions.

4. The design method of the energy dissipation device based on torsional deformation and air compression according to any one of claims 1 to 3, comprising the following steps: S1. According to the design requirements of the protective structure, determine the maximum working energy dissipation capacity E, the maximum working counterforce F and the impact force F required to start the energy dissipation device c ; Determine the calculation diameter D of the energy dissipation device according to the size of the upper connecting plate (11) and the lower mounting plate (22), determine the height range and deformation stroke range of the energy dissipation device according to the required clearance requirements and the size of the main structure required by the protective structure design, and then preliminarily determine the energy dissipation stroke h c ; S2, according to the maximum working reaction force F and the impact force F required to start the energy dissipation device c The diameter D1 of the energy dissipation metal rod, the engagement pitch P of the upper sleeve (14) and the lower sleeve (21) are determined as follows: The maximum working reaction force F is composed of two parts, one is the reaction force F required by the energy dissipation of the energy dissipation metal rod during starting h , and the other is the maximum reaction force F generated by the compression of the air spring in the sleeve q , that is: F = F h + F q (1) The above starting energy consumption metal rod energy consumption required counter force F h Is calculated as follows: In the formula, D is the calculated diameter of the energy dissipation device, and is the distance from the center of the threaded tooth of the energy dissipation device to the center of the circle; T P is the yield torque of the energy dissipation metal rod, and is calculated according to the formula τ y is the shear yield strength of the energy dissipation metal rod, D1 is the diameter of the energy dissipation metal rod; K h is a conversion coefficient, and is taken as k f is the friction coefficient between the upper rotating part and the lower fixed part, wherein θ is the included angle between the occlusal surface of the upper rotating part and the lower fixed part and the horizontal plane, and is obtained from the geometric relationship of the calculated diameter D and the pitch P of the energy dissipation device, and the geometric relationship is P = πDtanθ. The maximum reaction force F generated by compression of the air spring in the sleeve above q is calculated by the following equation: where: V1 is the gas volume when the energy-consuming device travels to the end; V2 is the gas volume at the initial state of the energy-consuming device; γ is the adiabatic index of the gas, and is 1.4 for air; P2 is the initial gas pressure of the energy-consuming device; K q1 is the bias coefficient of the counterforce caused by the gas leakage and heat dissipation in the sleeve, and is obtained from the dynamic impact test; The upper rotating part is taken as the cylinder in the initial size, and the diameter D, height and stroke h of the energy dissipation device are calculated c The air compression ratio is determined The diameter D1 of the energy dissipation metal rod is adjusted, and the initially proposed size is calculated by formulas (1)-(3) to make the maximum working reaction force F calculated by formula (1) not greater than the design requirement of the protective structure in engineering, and the reaction force F required for energy dissipation of the energy dissipation metal rod calculated by formula (2) h The impact force F required for starting the energy dissipation device is not greater than c ; S3, after the diameter D1 of the energy dissipation metal rod, the engagement pitch P of the upper sleeve (14) and the lower sleeve (21) are initially determined, the maximum working energy dissipation capacity E is calculated according to the initially determined sizes; The maximum working energy consumption capacity E is composed of three parts, one is the rotation energy consumption E provided by the rotation of the energy consumption metal rod h , the second is the friction energy consumption E generated by the friction between the upper rotating part and the lower fixed part f , and the third is the compression energy consumption E generated by the compression of the air in the sleeve q , that is: E = E h + E f + E q (4) wherein: wherein: D1 is the diameter of the energy dissipation metal rod; τ y is the shear yield strength of the energy dissipation metal rod; θ p is the rotation angle of the energy dissipation metal rod, taken as the angle between the upper rotating part and the lower fixed part from the beginning of the yield of the energy dissipation metal rod to the end of the stroke of the energy dissipation device. P1 is the gas pressure when the energy consumption device is at the end of its stroke, and is calculated by the formula K q2 K is the energy consumption deviation coefficient due to gas leakage in the cylinder, and is obtained from the dynamic impact test. S4, comparing the maximum working energy consumption capacity E calculated in step S3 with the value required by the design of the protective structure, and if the requirement is not met, adjusting the compression ratio of the cylinder volume of the compressed gas in advance The specific adjustment method is as follows: the solid part of the upper sleeve of the upper rotating part is increased, the compression volume of the gas at the end of the adjustment is realized, the safety of the wall thickness of the upper sleeve and whether the maximum working reaction force F exceeds the design limit value are considered, if the requirements are not met, the sizes need to be re-determined, and the steps S2 to S4 are repeated until the design requirements are met. S5, the size of the energy consumption device is verified by dynamic impact test, and the geometric parameters and material parameters of the energy consumption device are determined.

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