Variable-stiffness combined seismic isolation system for variable-mass column-supported vertical silo and application method of variable-stiffness combined seismic isolation system

Abstract

The invention discloses a variable mass column bearing type vertical silo variable stiffness combined seismic isolation system and an application method, and relates to the technical field of building seismic resistance. The system comprises a variable-stiffness shock insulation support module, an overload protection damper module and a cooperative control assembly. The rigidity self-adaption under small / medium / large deformation of the variable-rigidity support is realized through a double-hemming structure; the overload protection damper avoids overload damage by means of an overflow valve pressure relief mechanism; the cooperative control assembly dynamically adjusts parameters according to the material storage state. During application, low-rigidity shock insulation is achieved under the small-earthquake / empty-bin working condition, rigidity linear improvement is achieved under the medium-earthquake / half-bin working condition, high-rigidity limiting is achieved under the large-earthquake / full-bin working condition, and overload protection is triggered. The problems that a traditional shock insulation technology is poor in adaptability and unbalanced in energy consumption and safety are solved, the acceleration response of the granary and the displacement of the shock insulation layer can be remarkably reduced, the method is suitable for newly building and transforming the column type concrete vertical silo, and an anti-seismic guarantee is provided for grain safety.

Description

Technical Field

[0001] This invention belongs to the technical field of seismic isolation and resistance of buildings, specifically relating to a variable mass column-supported vertical silo variable stiffness combined seismic isolation system and its application method. Background Technology As a key infrastructure for grain storage and transportation, the seismic performance of grain silos is directly related to food security. Column-supported concrete silos have become the mainstream form of grain storage due to their advantages such as large capacity and small footprint. However, the "rigid at the top and flexible at the bottom" mechanical characteristics of this type of structure make it prone to serious problems such as shear failure of the supporting columns, tilting of the silo, and excessive dynamic lateral pressure of the stored material during earthquakes. Especially in earthquake-prone areas, traditional non-seismic-isolated grain silos have an extremely high risk of seismic damage.

[0002] Existing seismic isolation technologies for grain silos mostly employ traditional laminated rubber bearings or lead-core rubber bearings, which have inherent limitations that are difficult to overcome: (1) Significant adaptability issues: Traditional seismic isolation bearings have fixed stiffness, which cannot match the large fluctuations in mass of grain silos during the process of "empty-half-full"; in the empty state, the structural mass is small, and the fixed stiffness leads to a higher frequency of the seismic isolation system, which increases the efficiency of seismic energy transmission and significantly weakens the seismic isolation effect; in the full state, the structural mass increases significantly, the bearing deformation exceeds the safe range, which can easily cause the rubber layer to tear or the connection to fail, resulting in system collapse.

[0003] (2) Imbalance between energy dissipation mechanism and safety protection: Although ordinary viscous dampers can provide basic energy dissipation capacity, under rare earthquakes or near-fault pulse earthquakes, the output of the damper may rise sharply, exceeding the bearing limit of the connecting parts or support columns, leading to local structural damage and amplifying the risk of damage to the silo.

[0004] (3) Insufficient control capability of multi-level earthquake response: Under the action of multi-level earthquakes such as minor earthquakes, moderate earthquakes and major earthquakes, traditional combined seismic isolation systems are difficult to dynamically adjust stiffness and damping characteristics. Either the acceleration response is too large during minor earthquakes, or the displacement of the isolation layer is out of control during major earthquakes, which cannot meet the seismic resistance goal of "no damage during minor earthquakes, repairable during moderate earthquakes, and no collapse during major earthquakes".

[0005] Therefore, there is an urgent need for a combined seismic isolation scheme that can intelligently adapt to the changing mass conditions of grain silos, effectively cope with multi-level earthquakes, and integrate stiffness adaptive adjustment and damper overload protection functions to solve the above-mentioned structural defects. Summary of the Invention

[0006] To address the seismic requirements of variable-mass column-supported concrete silos under different storage conditions, and the problems of poor adaptability, energy consumption, and safety imbalance of traditional seismic isolation technologies, this invention provides a variable-stiffness combined seismic isolation system and application method for variable-mass column-supported silos. Through the coordinated work of variable-stiffness seismic isolation bearings and overload protection dampers, adaptive seismic isolation control under different mass conditions and multi-level earthquakes can be achieved, ensuring the structural safety of the grain silo and the safety of the stored materials.

[0007] The first objective of this invention is to provide a variable-mass column-supported vertical silo variable-stiffness combined seismic isolation system, including variable-stiffness seismic isolation bearings, overload protection dampers, and collaborative control components. The variable stiffness seismic isolation bearing includes an upper end plate, a lower end plate, a sandwich steel plate, and a high-damping rubber layer. The upper end plate and the lower end plate are respectively connected to the bottom of the grain silo support column and the foundation. The sandwich steel plate has a double rolled edge structure, and the sandwich steel plate and the high-damping rubber layer are alternately stacked and vulcanized. The overload protection damper includes a cylinder, a piston rod, damping fluid, and an overflow valve. The two ends of the cylinder are hinged to the grain bin ring beam and the foundation, respectively. The overflow valve has a built-in preload spring. The inlet of the overflow valve is connected to the left cavity of the cylinder, and the outlet is connected to the right cavity of the cylinder to form a pressure relief circuit. The collaborative control component is used to dynamically adjust the rolled edge constraint degree of the variable stiffness seismic isolation bearing and the preload of the overload protection damper according to the storage status of the grain silo, so as to achieve adaptive control of stiffness and damping.

[0008] Preferably, the double-rolled edge structure is a combination of "right angle + rounded corner" structure, with a roll height of 1.5~2.0mm; when the shear strain ≤100%, the double-rolled edge structure has a weak constraint on the high-damping rubber layer; when the shear strain is between 100% and 250%, the double-rolled edge structure forms a linear constraint on the high-damping rubber layer; when the shear strain ≥250%, the double-rolled edge structure is fully engaged.

[0009] Preferably, the high-damping rubber layer has a hardness of 50±5 IRHD, a damping ratio of ≥15%, and a total thickness that satisfies the first shape factor. S 1≥15, Second shape factor S 2≥5.

[0010] Preferably, the variable stiffness seismic isolation bearings are evenly arranged circumferentially along the grain silo support columns; the overload protection dampers are symmetrically arranged radially along the grain silo, and the overload protection dampers and the variable stiffness seismic isolation bearings form a "rigid-flexible" collaborative system.

[0011] Preferably, the output force of the overload protection damper conforms to the formula: , Among them, the damping coefficient =20~50kN·s α / mm, To protect the relative displacement of the connecting components at both ends of the overload protection damper, The relative velocity of the damper is at The first derivative, derived from the first derivative, represents the velocity difference between the connecting components at both ends of the damper. This is a core kinematic parameter that determines the magnitude of the damping force; the more severe the structural vibration, the greater the impact. The larger the absolute value of the damper, the greater the change in the damping index. α =0.3~0.6.

[0012] Preferably, the damping fluid is silicone oil with a viscosity range of 500~1000 cSt; the pre-pressure of the overflow valve is adjustable, and the output protection value is [not specified]. F npro The value is 300~500kN.

[0013] Preferably, the parameter matching logic of the collaborative control component is as follows: when the chamber is empty, the pre-pressure of the overflow valve is adjusted to 300kN, and the flange spacing of the variable stiffness seismic isolation bearing is 3~5mm; when the chamber is full, the pre-pressure of the overflow valve is adjusted to 500kN, and the flange spacing of the variable stiffness seismic isolation bearing is 2~3mm.

[0014] Preferably, the upper and lower end plates are made of Q345 high-strength steel and are connected to the bottom of the grain silo support column and the foundation by bolts; the sandwich steel plate is made of Q460 steel.

[0015] The second objective of this invention is to provide an application method for a variable-mass column-supported vertical silo variable-stiffness combined seismic isolation system, including the following working conditions: Minor earthquake / empty silo condition: Peak ground acceleration (PGA) ≤ 0.07g, minimum silo mass; variable stiffness seismic isolation bearings are in a low stiffness stage, shear strain ≤ 100%, weakening the upward transmission of seismic energy; overload protection dampers dissipate energy using conventional viscous oscillation. Moderate earthquake / half-silo condition: Peak ground acceleration (PGA) = 0.07~0.2g, grain silo quality is moderate; shear strain of variable stiffness seismic isolation bearings is between 100% and 250%, double-rolled edge gradually constrained rubber layer, stiffness linearly increased by 30%~50%; overload protection damper output is close to... F npro ; Major earthquake / full silo condition: Peak ground acceleration (PGA) ≥ 0.2g, maximum silo mass; variable stiffness seismic isolation bearing shear strain ≥ 250%, double-layered fully engaged, stiffness increased by 80%~100%; overload protection damper triggers overload protection, output stabilizes at... F npro .

[0016] Preferably, the system is suitable for column-supported concrete silos with a height-to-diameter ratio of 1.3 to 2.7; under multi-level earthquakes, the silo top acceleration amplification factor is ≤1.8, the seismic isolation layer displacement is ≤150mm, the dynamic lateral pressure coefficient of the stored material is ≤1.8, the lateral pressure at the bottom of the silo wall is ≤200kPa, and the displacement angle of the supporting column is ≤1 / 550.

[0017] The beneficial effects of this invention are: (1) Excellent adaptability to variable mass: Through the double-rolled edge structure and the dynamic adjustment of the pre-pressure of the overflow valve, the stiffness and damping adaptive control under variable mass conditions such as empty chamber, half chamber, and full chamber are realized, which solves the defect of the traditional seismic isolation bearing that is "rigid to the end", and the seismic isolation efficiency is improved by 40%~60% compared with the traditional technology.

[0018] (2) Multi-level earthquake compatibility: low stiffness isolation during minor earthquakes, linear stiffness transition during moderate earthquakes, and high stiffness limit during major earthquakes. Combined with overload protection of dampers, it can effectively meet the seismic target of "no damage during minor earthquakes, repairable during moderate earthquakes, and no collapse during major earthquakes". The acceleration response of the warehouse roof is reduced by 50% to 70%, and the displacement of the isolation layer is controlled within 50% of the standard limit.

[0019] (3) Excellent safety and durability: The double-rolled edge structure of the variable stiffness support effectively avoids excessive deformation of the rubber layer, and the overload protection damper limits the maximum output, significantly reducing the risk of damage to the support column and connectors; the selection of high-damping rubber and high-strength steel improves the system durability, with a service life of ≥50 years.

[0020] (4) Strong engineering applicability: It adopts a modular design and can be directly applied to newly built grain warehouses. It can also be installed by modifying the existing grain warehouse foundation. The construction is simple and quick, and the engineering cost is reduced by 15% to 20% compared with traditional seismic isolation technology. It has a wide range of application value. Attached Figure Description

[0021] For ease of explanation, the present invention will be described in detail below with reference to specific embodiments and accompanying drawings.

[0022] Figure 1 This is a top view of the overall structure of the variable stiffness combined seismic isolation system of the present invention; Figure 2 This is a cross-sectional view of the variable stiffness seismic isolation bearing of the present invention; Figure 3 This is a schematic diagram of the overload protection damper of the present invention.

[0023] In the picture: 100 - Variable stiffness seismic isolation bearing; 110 - Upper end plate; 120 - Lower end plate; 130 - Sandwich steel plate; 140 - High damping rubber layer; 150 - Double rolled edge structure; 200 - Overload protection damper; 210 - Cylinder; 220 - Piston rod; 230 - Damping fluid; 240 - Overflow valve; 250 - Preload spring; 300 - Grain silo support column; 400 - Foundation. Detailed Implementation

[0024] The following are specific embodiments of the present invention described in conjunction with the accompanying drawings, further illustrating the technical solutions of the present invention. However, the present invention is not limited to these embodiments. Specific details, such as particular configurations and components, are provided in the following description merely to aid in a comprehensive understanding of the embodiments of the present invention. Therefore, those skilled in the art should understand that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present invention. Furthermore, for clarity and brevity, descriptions of known functions and structures have been omitted.

[0025] It should be noted that, unless otherwise specified, the embodiments and features described in this invention can be combined with each other.

[0026] like Figures 1-3 As shown, this embodiment provides a variable mass column-supported vertical silo variable stiffness combined seismic isolation system, including a variable stiffness seismic isolation bearing 100, an overload protection damper 200, and a collaborative control component. The specific structure and connection relationship are as follows. The variable stiffness seismic isolation bearing 100 includes an upper end plate 110, a lower end plate 120, a sandwich steel plate 130, and a high-damping rubber layer 140. The upper end plate 110 and the lower end plate 120 are connected to the bottom of the grain silo support column 300 and the foundation 400, respectively. The sandwich steel plate 130 has a double-rolled edge structure 150, and the sandwich steel plate 130 and the high-damping rubber layer 140 are alternately stacked and vulcanized. Further, the upper end plate 110 and the lower end plate 120 are made of Q345 high-strength steel and are connected to the bottom of the grain silo support column 300 and the foundation 400 by bolts; the sandwich steel plate 130 is made of Q460 steel; the double-rolled edge structure 150 is a combination of "right angle + rounded corner" structure, with a roll height of 1.5~2.0mm; the hardness of the high-damping rubber layer 140 is 50±5IRHD, the damping ratio is ≥15%, and the total thickness of the high-damping rubber layer meets the first shape factor requirement. S 1≥15, Second shape factor S 2≥5.

[0027] When under minor earthquakes / empty chamber conditions, the shear strain is ≤100%, and the double-rolled edge structure 150 provides weak constraint on the high-damping rubber layer 140. The variable stiffness isolation bearing 100 maintains low stiffness to ensure isolation efficiency. When under moderate earthquakes / half-chamber conditions, the shear strain is between 100% and 250%. The double-rolled edge structure 150 forms a linear constraint on the high-damping rubber layer 140, gradually compressing the rubber layer. The stiffness of the variable stiffness isolation bearing 100 increases linearly, balancing the requirements for isolation and lateral displacement resistance. When under major earthquakes / full chamber conditions, the shear strain is ≥250%. The double-rolled edge structure 150 is fully engaged, and the variable stiffness isolation bearing 100 enters a high stiffness stage, limiting the displacement of the isolation layer and preventing bearing tearing.

[0028] The overload protection damper 200 includes a cylinder 210, a piston rod 220, a high-viscosity damping fluid 230, and an overflow valve 240. The cylinder 210 is hinged at both ends to the grain silo ring beam and the foundation 400, respectively. The high-viscosity damping fluid 230 is silicone oil with a viscosity range of 500~1000 cSt. The overflow valve 240 has a built-in preload spring 250 with adjustable preload and output protection value. F npro The pressure is 300~500kN; the inlet of the overflow valve 240 is connected to the left cavity of the cylinder 210, and the outlet is connected to the right cavity of the cylinder 210 to form a pressure relief circuit. During a normal earthquake (damping force < design protection value)... F npro The damping fluid 230 generates viscous damping through the piston gap, and the output force of the overload protection damper conforms to the formula: Among them, the damping coefficient =20~50kN·s α / mm, To protect the relative displacement of the connecting components at both ends of the overload protection damper, The relative velocity of the damper is at The first derivative, derived from the first derivative, represents the velocity difference between the connecting components at both ends of the damper. This is a core kinematic parameter that determines the magnitude of the damping force; the more severe the structural vibration, the greater the impact. The larger the absolute value of the damping force, the greater the change in the damping output. The damping index α = 0.3~0.6. In rare earthquakes (damping force ≥ 0.6), F npro When the pressure is released, the overflow valve 240 opens against the preload of the preload spring 250, and the damping fluid 230 flows through the pressure relief channel, stabilizing the output at a certain level. F npro This is to prevent overload damage to the overload protection damper 200 and connecting parts.

[0029] Furthermore, the variable stiffness seismic isolation bearings 100 are uniformly arranged circumferentially along the grain silo support columns 300, so that the seismic energy is evenly distributed circumferentially, avoiding the torsional effect caused by asymmetrical arrangement. For example, each support column can be equipped with 4 variable stiffness seismic isolation bearings 100, with a total of 16 to 24, ensuring that the system covers the foundation interface of grain silos of different sizes. The overload protection dampers 200 are symmetrically arranged radially along the grain silo, such as 2 per radial direction, with a total of 4 to 8, so that the damping network density matches the stiffness distribution of the isolation layer. The overload protection dampers 200 and the variable stiffness seismic isolation bearings 100 form a "rigid-flexible" synergistic system. In the small deformation stage, the bearings provide flexible seismic isolation to weaken the transmission of seismic energy, and the dampers dissipate the vibration energy synchronously. In the large deformation stage, the displacement is limited by the preset overload protection mechanism, and together they achieve dynamic matching of stiffness and damping from empty to full silo conditions, thereby solving the problem of uneven load transmission.

[0030] The collaborative control component dynamically adjusts the rolled edge constraint of the variable stiffness seismic isolation bearing 100 and the preload of the overload protection damper 200 according to the storage status of the grain silo, achieving adaptive control of stiffness and damping. The parameter matching logic of the collaborative control component is dynamically adjusted based on the height-to-diameter ratio of the grain silo (H / D = 1.3~2.7) and the storage status. In the empty silo state, the preload of the overflow valve 240 is adjusted to... F npro =300kN, the flange spacing of the variable stiffness seismic isolation bearing 100 is 3~5mm, prioritizing seismic isolation efficiency; in full load condition, the preload of the overflow valve 240 is adjusted to F npro =500kN, the flange spacing of the variable stiffness seismic isolation bearing 100 is 2~3mm, which enhances stiffness and overload protection.

[0031] Specifically, the collaborative control component automatically adjusts the pre-pressure of the overflow valve 240 and the flange spacing by monitoring the grain storage status in real time. In an empty silo, the system sets the pre-pressure of the overflow valve 240 to a low value of 300kN, allowing the overload protection damper 200 to effectively dissipate seismic energy without triggering overload protection under minor earthquakes. Simultaneously, the flange spacing is increased to 3-5mm, weakening the constraint of the double-flange structure 150 on the high-damping rubber layer 140, maintaining a low support stiffness, and thus mitigating seismic response. In a full silo, the system increases the pre-pressure of the overflow valve 240 to 500kN, ensuring the overload protection damper 200 provides stable output during major earthquakes and controlling the displacement of the isolation layer. At the same time, the flange spacing is reduced to 2-3mm, allowing the double-flange structure 150 to fully engage, significantly improving support stiffness and preventing excessive deformation. This parameter matching logic enables the system to adapt to varying mass conditions and optimize seismic isolation performance.

[0032] This embodiment also provides an application method for the above-mentioned variable stiffness combined seismic isolation system. This system is suitable for column-supported concrete silos with a height-to-diameter ratio of 1.3 to 2.7, including the following working conditions: Minor earthquake / empty silo condition: Peak ground acceleration (PGA) ≤ 0.07g, minimum silo mass; variable stiffness isolation bearing 100 is in low stiffness stage, shear strain ≤ 100%, weakening the upward transmission of seismic energy; overload protection damper 200 did not trigger overload, and vibration reduction was assisted by viscous energy dissipation, silo top acceleration amplification factor ≤ 1.2, and isolation layer displacement ≤ 50mm.

[0033] Moderate earthquake / half-silo condition: Peak ground acceleration (PGA) = 0.07~0.2g, grain silo quality is moderate; variable stiffness seismic isolation bearing 100 has shear strain between 100% and 250%, double-rolled edge construction 150 gradually constrains the rubber layer, linearly increasing stiffness by 30%~50%; overload protection damper 200 output is close to... F npro The dynamic lateral pressure coefficient of the storage material is ≤1.8 (the standard limit is 2.0), and the displacement angle of the support column is ≤1 / 550.

[0034] Major earthquake / full silo condition: Peak ground acceleration (PGA) ≥ 0.2g, maximum silo mass; variable stiffness seismic isolation bearings with shear strain ≥ 250%, double-rolled edge construction with complete interlocking, stiffness increased by 80%~100%, limiting isolation layer displacement ≤ 150mm (standard limit 270mm); overload protection damper 200 triggers overload protection, output stabilizes at... F npro The bottom lateral pressure of the silo wall should be ≤200kPa to prevent the silo body from cracking.

[0035] Specifically, this technical solution ensures that the aforementioned variable stiffness combined seismic isolation system can effectively coordinate seismic response control and structural safety requirements in grain silos of specific sizes by limiting the range of geometric parameters of the silo and setting performance index thresholds under multi-level earthquakes. The height-to-diameter ratio limit of 1.3~2.7 matches the dynamic adjustment capability of the silo stiffness with that of the variable stiffness seismic isolation bearings, avoiding reduced isolation efficiency due to an excessively small height-to-diameter ratio or overall instability due to an excessively large ratio, thus ensuring the system's stable operation during changes in silo mass from empty to full. An acceleration amplification factor of ≤1.2 at the silo top effectively suppresses the upward transmission of high-frequency vibrations during minor earthquakes, while limiting the acceleration response amplitude under moderate to large earthquakes. The requirement of isolation layer displacement ≤150mm ensures the continuity of the system's seismic isolation function under large earthquakes. The indices of a dynamic lateral pressure coefficient of ≤1.8 and a lateral pressure at the bottom of the silo wall ≤200kPa limit the amplitude of lateral pressure changes, preventing structural damage to the grain silo during dynamic changes in silo mass. Controlling the displacement angle of the support column to ≤1 / 550 can effectively coordinate the deformation capacity and load-bearing requirements of the support column, and avoid shear failure during earthquakes.

[0036] This method is based on the dual changes in earthquake intensity and storage conditions, driving the variable stiffness seismic isolation bearing 100 to achieve step-wise adaptive adjustment of stiffness within the shear strain range. At the same time, the automatic pressure relief function of the overflow valve 240 ensures that the overload protection damper 200 outputs stably under extreme conditions. This effectively solves the problem of insufficient adaptability of traditional seismic isolation technology in variable mass grain silos due to fixed stiffness, and avoids local structural damage caused by the damper output exceeding the limit under rare earthquakes. Ultimately, it achieves the seismic resistance goal of "no damage in small earthquakes, repairable in moderate earthquakes, and no collapse in large earthquakes" under multi-level earthquake action.

[0037] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0038] In the description of this application, it should be understood that the terms "upper" and "lower" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

Claims

1. A variable-mass column-supported vertical silo variable-stiffness combined seismic isolation system, characterized in that, include: Variable stiffness seismic isolation bearing (100), overload protection damper (200), and coordinated control components; The variable stiffness seismic isolation bearing (100) includes an upper end plate (110), a lower end plate (120), a sandwich steel plate (130), and a high-damping rubber layer (140). The upper end plate (110) and the lower end plate (120) are respectively connected to the bottom of the grain storage support column (300) and the foundation (400). The sandwich steel plate (130) is provided with a double rolled edge structure (150) at its edge, and the sandwich steel plate (130) and the high-damping rubber layer (140) are alternately stacked and vulcanized. The overload protection damper (200) includes a cylinder (210), a piston rod (220), a damping fluid (230), and an overflow valve (240). The two ends of the cylinder (210) are respectively hinged to the grain bin ring beam and the foundation (400). The overflow valve (240) has a built-in preload spring (250). The inlet of the overflow valve (240) is connected to the left cavity of the cylinder (210), and the outlet is connected to the right cavity of the cylinder (210) to form a pressure relief circuit. The collaborative control component is used to dynamically adjust the degree of edge restraint of the variable stiffness seismic isolation bearing (100) and the preload of the overload protection damper (200) according to the storage status of the grain silo, so as to realize the adaptive control of stiffness and damping.

2. The variable mass column-supported vertical silo variable stiffness combined seismic isolation system according to claim 1, characterized in that, The double-rolled edge structure (150) is a combination of "right angle + rounded corner" structure, and the rolled edge height is 1.5~2.0mm; When the shear strain is ≤100%, the double-rolled edge structure (150) has a weak constraint on the high-damping rubber layer (140); when the shear strain is between 100% and 250%, the double-rolled edge structure (150) forms a linear constraint on the high-damping rubber layer (140); when the shear strain is ≥250%, the double-rolled edge structure (150) is fully engaged.

3. The variable mass column-supported vertical silo variable stiffness combined seismic isolation system according to claim 1, characterized in that, The high-damping rubber layer (140) has a hardness of 50±5 IRHD, a damping ratio of ≥15%, and a total thickness that satisfies the first shape factor. S 1≥15, Second shape factor S 2≥5.

4. The variable mass column-supported vertical silo variable stiffness combined seismic isolation system according to claim 1, characterized in that, The variable stiffness seismic isolation bearing (100) is uniformly arranged around the grain storage support column (300); the overload protection damper (200) is symmetrically arranged radially around the grain storage, and the overload protection damper (200) and the variable stiffness seismic isolation bearing (100) form a "rigid-flexible" collaborative system.

5. A variable-mass column-supported vertical silo variable-stiffness combined seismic isolation system according to claim 1, characterized in that, The output force of the overload protection damper (200) conforms to the formula: ， Among them, the damping coefficient =20~50kN·s α / mm, To protect the relative displacement of the connecting components at both ends of the overload protection damper, The relative velocity of the damper is at The first derivative, derived from the first derivative, represents the velocity difference between the connecting components at both ends of the damper. This is a core kinematic parameter that determines the magnitude of the damping force; the more severe the structural vibration, the greater the impact. The larger the absolute value of the damper, the greater the change in the damping index. =0.3~0.

6.

6. A variable-mass column-supported vertical silo variable-stiffness combined seismic isolation system according to claim 1, characterized in that, The damping fluid (230) is silicone oil with a viscosity range of 500~1000 cSt; the pre-pressure of the overflow valve (240) is adjustable, and the output protection value is [not specified]. F npro The value is 300~500kN.

7. A variable-mass column-supported vertical silo variable-stiffness combined seismic isolation system according to claim 1, characterized in that, The parameter matching logic of the collaborative control component is as follows: when the chamber is empty, the pre-pressure of the overflow valve (240) is adjusted to 300kN, and the edge spacing of the variable stiffness seismic isolation support (100) is 3~5mm; when the chamber is full, the pre-pressure of the overflow valve (240) is adjusted to 500kN, and the edge spacing of the variable stiffness seismic isolation support (100) is 2~3mm.

8. A variable-mass column-supported vertical silo variable-stiffness combined seismic isolation system according to claim 1, characterized in that, The upper end plate (110) and lower end plate (120) are made of Q345 high-strength steel and are connected to the bottom of the grain silo support column (300) and the foundation (400) by bolts; the sandwich steel plate (130) is made of Q460 steel.

9. An application method of the variable stiffness combined seismic isolation system as described in any one of claims 1 to 8, characterized in that, Including the following working conditions: Small earthquake / empty warehouse condition: peak ground acceleration PGA ≤ 0.07g, minimum mass of grain warehouse; variable stiffness isolation bearing (100) is in low stiffness stage, shear strain ≤ 100%, weakening the upward transmission of seismic energy; Overload protection damper (200) conventional viscous energy dissipation; Moderate earthquake / half-silo condition: Peak ground acceleration (PGA) = 0.07~0.2g, grain silo quality is moderate; variable stiffness isolation bearing (100) shear strain is between 100% and 250%, double rolled edge gradually constrains the rubber layer, stiffness linearly increases by 30%~50%; overload protection damper (200) output is close to the output protection value. F npro ; Major earthquake / full silo condition: Peak ground acceleration (PGA) ≥ 0.2g, maximum silo mass; variable stiffness isolation bearing (100) shear strain ≥ 250%, double rolled edges fully engaged, stiffness increased by 80%~100%; overload protection damper (200) triggers overload protection, output stabilizes at the output protection value. F npro .

10. The application method of a variable-mass column-supported vertical silo variable-stiffness combined seismic isolation system according to claim 9, characterized in that, The system is suitable for column-supported concrete silos with a height-to-diameter ratio of 1.3 to 2.

7. Under multi-level earthquakes, the silo top acceleration amplification factor is ≤1.8, the seismic isolation layer displacement is ≤150mm, the dynamic lateral pressure coefficient of the stored material is ≤1.8, the lateral pressure at the bottom of the silo wall is ≤200kPa, and the displacement angle of the supporting column is ≤1 / 550.

Images