Underground structures with nonlinear inertial-compressive multi-stage self-resetting central columns under three-dimensional seismic motion

Abstract

This invention relates to an underground structure with a nonlinear inertial-capacitive multi-stage self-resetting central column under three-dimensional seismic motion. The structure includes a top plate, a bottom plate, side walls, multi-segmented self-resetting columns, and a nonlinear inertial-capacitive self-resetting friction damper. The top plate, bottom plate, and side walls form an underground space structure. Vertically segmented self-resetting columns are arranged between the top and bottom plates. A nonlinear inertial-capacitive self-resetting friction damper is vertically arranged on the outer side of the connection between each segment of the self-resetting column. This nonlinear inertial-capacitive self-resetting friction damper includes a shaft, a clamping plate, and a rotating block. The clamping plate holds the rotating block, which is sleeved on the shaft, which connects to the self-resetting column. Shape memory alloy stranded wire is wound around the outside of the clamping plate. Compared with existing technologies, this invention can achieve multi-stage swaying response, nonlinear inertial energy absorption-energy dissipation enhancement, and dual self-resetting functions in underground structures under multi-dimensional seismic loading, and is easy to implement modularly.

Description

Technical Field

[0001] This invention belongs to the field of seismic isolation and vibration reduction technology for underground structures, and relates to an underground structure with a nonlinear inertial-capacitive multi-stage self-resetting central column under three-dimensional seismic motion. Background Technology

[0002] With the development of society and economy, urban underground space has been continuously developed, resulting in underground space structures such as underground rail transit, underground commercial streets, and underground complexes. Underground space structures can achieve spatial complementarity and integrate urban functions, which has attracted increasing attention from urban planners and led to rapid development, with the number of developments and the scale of structures growing day by day.

[0003] Traditionally, it was believed that underground structures, embedded in the soil, possessed good seismic resistance due to the soil's constraint on structural deformation. However, investigations into actual earthquake damage have shown that underground structures can suffer severe damage under seismic forces. Furthermore, post-earthquake repair of underground structures is extremely difficult, especially for densely populated and complex structures, resulting in incalculable direct and indirect losses.

[0004] Currently, the energy-dissipating self-resetting column system used in underground space structures typically replaces the cast-in-place joint between the column base and top with a hinged connection. Dampers and prestressed steel strands are installed at the column ends to achieve energy dissipation by the dampers during earthquakes and self-resetting under the tension of the steel strands after an earthquake. However, this type of energy-dissipating self-resetting column system can only set a single swing threshold by adjusting the prestress of the steel strands. The self-resetting column can only sway under a preset level of earthquake action, triggering the energy dissipation behavior of the preset dampers, thus achieving the effect of energy dissipation and vibration reduction. At the epicenter, it can only rely on the swaying central column to absorb earthquake energy; after the earthquake, a comprehensive inspection and repair of the energy-dissipating self-resetting column is required, which is large in scale, costly, and difficult. Furthermore, energy-dissipating self-resetting columns arranged along the entire height of the underground space structure also present difficulties in transportation and assembly due to their excessive size.

[0005] Currently widely used energy-dissipating self-resetting column systems only provide effective seismic isolation for horizontal seismic components, offering almost no isolation effect for vertical seismic components. However, ground motions near faults sometimes exhibit strong vertical seismic components, with peak vertical accelerations often exceeding those of the horizontal components, demonstrating a significant vertical acceleration effect. Commonly used thick-layer rubber bearing isolation methods suffer from low bearing capacity and susceptibility to instability under shear deformation, and are not easily integrated with energy-dissipating self-resetting column systems. Therefore, there is an urgent need to develop a multi-dimensional seismic isolation device that is structurally and performanceably compatible with energy-dissipating self-resetting column systems.

[0006] Patent CN112727220A discloses a self-resetting enhanced seismic isolation column and its underground space structure system, comprising self-resetting enhanced seismic isolation column units, an underground space structure top slab, an underground space structure bottom slab, and underground space structure sidewalls; the underground space structure top slab, underground space structure bottom slab, and underground space structure sidewalls together form a multi-layer, multi-span structural system with a rectangular cross-section, and several self-resetting enhanced seismic isolation column units are arranged between the underground space structure top slab and the underground space structure bottom slab at each level; under the action of earthquakes and impact loads, the underground space structure top slab and the underground space structure bottom slab undergo horizontal relative deformation, which in turn causes horizontal deformation of the underground space structure sidewalls and movement of the self-resetting enhanced seismic isolation column units; the self-resetting enhanced seismic isolation column unit includes tension prestressed steel bars and a top self-resetting friction energy dissipation damper device, the self-resetting mechanism of the tension prestressed steel bars in the self-resetting enhanced seismic isolation column unit works in conjunction with the top self-resetting friction energy dissipation damper to amplify the deformation of the top friction damper of the self-resetting enhanced seismic isolation column and improve its energy dissipation capacity; and ensure the self-resetting performance of the structure under multi-level earthquakes. Although this patent uses self-resetting enhanced isolation column units to realize the energy dissipation capacity and self-resetting function of underground space structures, the self-resetting central column only has a single swing threshold, making it difficult to widely realize its structural function under multi-level seismic action; the self-resetting enhanced unit is based on the self-resetting control force of prestressed steel bars and does not have the characteristics of inertial energy absorption and energy dissipation enhancement, and cannot solve the problems of low energy absorption efficiency of the main self-resetting components of underground structures and low contribution of structural lateral force resistance; on the other hand, the damper device used can only realize frictional energy dissipation based on horizontal relative displacement, which has low energy dissipation efficiency and is difficult to solve the amplification effect of vertical seismic action on the dynamic response of underground structures.

[0007] Patent CN106121336A discloses a shape memory alloy stranded wire-ring spring assembled self-resetting damper, including an energy dissipator, an inner sleeve, an outer sleeve, a disk, and two or more shape memory alloy (SMA) stranded wires. The energy dissipator is a ring spring energy dissipator arranged inside the inner sleeve. The outer sleeve and the inner sleeve are staggered to keep the SMA stranded wires under tension. One end of the inner sleeve is fixedly connected to a central shaft, and one end of the outer sleeve is fixedly connected to a guide shaft. The central shaft and the guide shaft pass through the central hole of the disk. The two or more SMA stranded wires are arranged separately and evenly along the circumference of the disk and fixedly connected to the disk. Although this patent uses SMA stranded wires and a sleeve assembly to achieve the function of a self-resetting damper, it directly achieves frictional energy dissipation based on the relative translation of the two ends, lacking energy dissipation efficiency enhancement capabilities. Faced with small displacements of building structures under multi-level seismic action, it is difficult to fully utilize its self-resetting energy dissipation capability, limiting its applicable working scenarios. Summary of the Invention

[0008] The purpose of this invention is to overcome at least one of the defects of the existing technology and provide an underground structure with a nonlinear inertial-capacitive multi-level self-resetting central column under three-dimensional seismic motion. This invention can realize the multi-level swaying response, nonlinear inertial energy absorption-energy dissipation enhancement and dual self-resetting function of the underground structure under multi-dimensional seismic action, and is easy to implement modular installation and tough prefabricated assembly underground structure construction.

[0009] The objective of this invention can be achieved through the following technical solutions:

[0010] One of the technical solutions of the present invention is to provide an underground structure of a nonlinear inertial-capacitive multi-stage self-resetting central column under three-dimensional seismic motion. The structure includes a top plate, a bottom plate, side walls, a multi-segment opening and closing self-resetting column, and a nonlinear inertial-capacitive self-resetting friction damper. The top plate, bottom plate, and side walls constitute an underground space structure, and vertically segmented self-resetting columns are arranged between the top plate and the bottom plate.

[0011] A nonlinear inertial capacitive self-resetting friction damper is vertically arranged on the outer side of the connection of the self-resetting column of each segment. The nonlinear inertial capacitive self-resetting friction damper includes a shaft, a clamping plate and a rotating block. The rotating block is clamped in the clamping plate and sleeved on the shaft. The shaft is connected to the self-resetting column.

[0012] The clamp is wound with shape memory alloy (SMA) strands, and the clamp and the rotating block are engaged with each other by the radial force provided by the shape memory alloy strands; at the same time, the deformation capacity of the shape memory alloy strands provides space for the clamp to open and close radially, and provides restoring force for the clamp.

[0013] As a preferred technical solution, nonlinear inertial capacitive self-resetting friction dampers are arranged vertically and symmetrically on both sides of the connection of the self-resetting columns of each segment.

[0014] As a preferred technical solution, the shape memory alloy stranded wire includes nickel-titanium-based shape memory alloy (Ni-TiSMA) stranded wire, copper-based shape memory alloy (Cu SMA) stranded wire, or iron-based shape memory alloy (Fe SMA) stranded wire.

[0015] Furthermore, the clamping plate is provided with internal threads, the rotating block is provided with external threads, the rotating block is vertically non-uniform in diameter, the clamping plate and the rotating block are matched by threads, so that the rotating block rotates along the threads inside the clamping plate, and the clamping plate undergoes radial displacement.

[0016] As a preferred technical solution, the non-uniform diameter rotating blocks are symmetrically installed.

[0017] Furthermore, the clamping plate is provided with a non-internal thread contact surface, and the rotating block is provided with a non-external thread contact surface. The mutual matching of the non-threaded contact surfaces between the clamping plate and the rotating block is the initial state.

[0018] Furthermore, a connecting rod is provided on the self-resetting column, and the shaft is hinged to the connecting rod through a hinged connector.

[0019] As a preferred technical solution, the hinged connector includes two steel rods and a set of hinge bolts.

[0020] Furthermore, a flywheel is fitted on the outside of the clamping plate on the shaft, and the flywheel rotates together with the rotating block.

[0021] As a preferred technical solution, flywheels are symmetrically fitted on both sides of the clamping plate on the shaft.

[0022] Furthermore, the self-resetting columns of each segment are connected in series with prestressed steel strands and connected to the top and bottom slabs.

[0023] Furthermore, the prestressed steel strand is fixed to the contact surface of the self-resetting column by a fastener.

[0024] As a preferred technical solution, the fixing component includes a steel bearing plate, a fixing clamp, and an adjusting bolt. The function of the steel bearing plate is to transmit the tension of the prestressed steel strand to the column section. The function of the fixing clamp is to fix the prestressed steel strand. The function of the adjusting bolt is to adjust the prestress value of the prestressed steel strand.

[0025] Furthermore, the prestressed steel strands require different prestress levels in each segment of the self-resetting column according to the starting swing sequence of the self-resetting column. The nonlinear inertial capacitive self-resetting friction damper is equipped with different self-resetting and energy dissipation capabilities in each segment of the self-resetting column according to the vibration reduction and energy dissipation requirements, thereby realizing the segmented starting swing of the self-resetting column.

[0026] As a preferred technical solution, the prestress values ​​of the prestressed steel strands of the self-resetting columns in each segment are set sequentially from small to large according to the swing sequence of the self-resetting columns. When a horizontal ground motion occurs, single-segment swing, two-segment swing, three-segment swing, and multi-segment swing can be achieved according to the ground motion magnitude. This not only realizes the energy dissipation of swing under ground motion, but also achieves graded response under different ground motion intensities.

[0027] Furthermore, by adjusting the roughness of the threaded contact surface between the clamping plate and the rotating block, as well as the material properties of the shape memory alloy strand, the action threshold of the nonlinear inertial capacitive self-resetting friction damper is adjusted; it is matched with the prestress value of the prestressed steel strand to achieve dual energy consumption enhancement and multi-level self-resetting restoring force working in synergy.

[0028] Furthermore, the top and bottom of the self-resetting column are provided with reinforcement members, the purpose of which is to reduce damage to the top and bottom of the self-resetting column during the swinging process.

[0029] As a preferred technical solution, the reinforcing member is selected from one or more of steel plates and high-grade concrete.

[0030] One of the technical solutions of the present invention is to provide a nonlinear inertial-capacitive multi-stage self-resetting method under three-dimensional seismic motion. This method uses the underground structure of the aforementioned nonlinear inertial-capacitive multi-stage self-resetting column under three-dimensional seismic motion for multi-stage self-resetting, and includes the following steps:

[0031] When the underground space structure is subjected to earthquake vibration, the top plate and the bottom plate undergo relative deformation, which in turn causes the self-resetting column to sway.

[0032] The prestressed steel strands of the series segmented self-resetting column and the nonlinear inertial capacitive self-resetting friction dampers installed on both sides of the connection of the self-resetting column provide energy dissipation and restoring force for the self-resetting column.

[0033] The relative deformation of the external structure acts on the nonlinear inertial capacitive self-resetting friction damper through the hinged connector and shaft. The rotation of the rotating block along the thread causes the clamping plate to undergo radial displacement and the flywheel to rotate. At this time, part of the energy is dissipated through the inertial capacitive friction energy dissipation effect.

[0034] After the excitation of the external structure ends, the shape memory alloy strands on the outer side of the clamping plate provide radial restoring force and also allow the clamping plate to undergo radial opening and closing motion under the action of the rotating block. The restoring force pushes the rotating block to return to the initial state along the thread. In this process, the restoring force acts on the self-resetting column through the hinged connector and the shaft, pushing the self-resetting column to return to its original position and reducing its residual displacement.

[0035] When a horizontal seismic action occurs on an underground space structure, the segmented self-resetting column begins to sway. Firstly, the swaying causes tensile deformation of the prestressed steel strands, providing primary restoring force and damping energy dissipation for the self-resetting column. Secondly, the swaying causes vertical displacement of the bottom surface of the self-resetting column, which drives the movement of the rotating block in the nonlinear inertial capacitive self-resetting friction damper. The relative movement between the rotating block and the clamping plate, as well as the rotation of the flywheel, realizes amplified inertial energy absorption and enhanced frictional energy dissipation based on the inertial capacitive element. At the same time, the threaded design of the contact surface between the rotating block and the clamping plate and the shape memory alloy strands on the outside of the clamping plate provide secondary restoring force for the self-resetting column.

[0036] When vertical seismic action is applied to underground space structures, the compression and tension between the segmented self-resetting columns in the vertical distance provide vertical displacement for the nonlinear inertial capacitive self-resetting friction damper, which drives the rotating block and the clamping plate to generate amplified inertial energy absorption and enhanced frictional energy dissipation based on the inertial capacitive element. At the same time, the thread design of the contact surface between the rotating block and the clamping plate and the shape memory alloy stranded wire on the outside of the clamping plate provide additional vertical restoring force for the self-resetting column.

[0037] When the underground space structure is subjected to multidimensional seismic activity, the structure will simultaneously protect the safety of the underground space structure in the two ways mentioned above: by dissipating energy and by providing restoring force.

[0038] Compared with the prior art, the present invention has the following beneficial effects:

[0039] (1) This invention realizes the segmented response, enhanced energy absorption-energy dissipation and multi-level self-resetting of the inertial capacity enhanced energy dissipation self-resetting column and underground space system under multi-level earthquake action. By using steel strands with different prestress values ​​set according to the earthquake magnitude and nonlinear inertial capacity self-resetting friction dampers, the segmented swing of the inertial capacity enhanced self-resetting energy dissipation self-resetting column and the double self-resetting and enhanced inertial energy absorption-energy dissipation in each segment are realized. It overcomes the shortcomings of existing underground space structures where energy dissipation self-resetting columns are difficult to play a role in small and medium earthquakes, the self-resetting mechanism is insufficient under large earthquakes, the mechanism is simple and the redundancy is low.

[0040] (2) In the longitudinal direction, the central column is segmented and connected to each other by prestressed steel strands to form a segmented self-resetting central column. The prestress value of the steel strands can provide the self-resetting force of the central column. Furthermore, by adjusting the prestress value of the steel strands of each segment of the central column, the multi-level swaying function and the first self-resetting function of the central column are realized, thereby improving the swaying energy consumption response capability of the central column.

[0041] (3) In this invention, nonlinear inertial capacitive self-resetting friction dampers are arranged vertically on both sides of the contact surface of each column. The relative displacement between the self-resetting columns causes the rotating block of the nonlinear inertial capacitive self-resetting friction damper to rotate along the thread and the clamp to open. The rotating block drives the flywheel to rotate, which can generate a significant nonlinear inertial capacitive coefficient and inertial control energy absorption effect. At the same time, the shape memory alloy strands arranged around the outside of the nonlinear inertial capacitive self-resetting friction damper can provide additional self-resetting force and composite damping effect. It realizes the energy absorption-dissipation enhancement and second self-resetting function under multidimensional seismic action. The vertical inertial control and energy dissipation enhancement effect in the nonlinear inertial capacitive self-resetting friction damper can specifically alleviate the response amplification problem of underground structures under vertical seismic action.

[0042] (4) This invention utilizes the swaying deformation of the segmented self-resetting column to enhance the vibration reduction and energy dissipation efficiency of the underground space system under horizontal and vertical multidimensional earthquakes by setting nonlinear inertial capacitive self-resetting friction dampers with different self-resetting and energy dissipation capabilities on both sides of the connection of each segment of the self-resetting column. The setting of nonlinear inertial capacitive self-resetting friction dampers can effectively meet the vibration reduction and energy dissipation requirements caused by the inertial action of the upper covering soil in the vertical earthquake action of the underground space structure. It can also coordinately control the horizontal deformation of the column in the underground space structure, constrain the sidewall of the underground space structure with the help of multi-segment self-resetting stiffness, and reduce its lateral deformation, thereby further improving the stability of the self-resetting underground space structure system.

[0043] (5) This invention realizes multiple toughness mechanisms of inertial capacity enhanced energy dissipation self-resetting column and underground space system through prestressed steel strand and nonlinear inertial capacitive self-resetting friction damper; it can limit the swing amplitude of self-resetting column while providing energy dissipation, and reduce the residual deformation of structure after the earthquake.

[0044] (6) This invention proposes a nonlinear inertial-capacitive damping design scheme for underground space structures in response to three-dimensional seismic motion. It achieves the effect of composite self-resetting and superimposed energy dissipation of underground structures. It features a segmented design, simple structure, and small size of a single self-resetting column, making it suitable for use as a prefabricated component. It is easy to implement modular installation and tough prefabricated assembly underground structure construction. It is also convenient to replace and repair the failed self-resetting column segment in the event of structural damage after a major earthquake. It can be applied to key seismic parts such as columns in underground structures, and can effectively improve the overall seismic performance of the structure. Attached Figure Description

[0045] Figure 1 This is a front view cross-sectional schematic diagram of the underground structure of the nonlinear inertial-compressive multi-stage self-resetting central column under three-dimensional seismic motion in an embodiment of the present invention.

[0046] Figure 2 This is a schematic diagram of the front cross-sectional structure of the top of the self-resetting column in an embodiment of the present invention;

[0047] Figure 3 This is a schematic diagram of the front cross-sectional structure of the self-resetting column in an embodiment of the present invention;

[0048] Figure 4 This is a schematic diagram of the front cross-sectional structure of the self-resetting column base in an embodiment of the present invention;

[0049] Figure 5 This is a side view cross-sectional schematic diagram of the underground structure of the nonlinear inertial-compressive multi-stage self-resetting central column under three-dimensional seismic motion in an embodiment of the present invention.

[0050] Figure 6 This is a schematic diagram of the side cross-sectional structure of the self-resetting column in an embodiment of the present invention;

[0051] Figure 7 This is a front view cross-sectional schematic diagram of the nonlinear inertial capacitive self-resetting friction damper in an embodiment of the present invention;

[0052] Figure 8 This is a top view of the cross-sectional structure of the nonlinear inertial capacitive self-resetting friction damper in an embodiment of the present invention.

[0053] Explanation of markings in the diagram:

[0054] 1—Top plate, 2—Bottom plate, 3—Side wall, 4—Self-resetting column, 5—Nonlinear inertial capacitive self-resetting friction damper, 6—Fixed component, 7—Prestressed steel strand, 8—Reinforcing component, 9—Hinged connector, 10—Shaft, 11—Flywheel, 12—Clamping plate, 13—Rotating block, 14—Shape memory alloy strand. Detailed Implementation

[0055] The present invention will now be described in detail with reference to specific embodiments. These embodiments are based on the technical solution of the present invention and provide detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments.

[0056] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., 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 invention and for 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 invention. Furthermore, the terms "first," "second," "third," etc., used to describe a common object only indicate different instances of the same object, and do not imply that the objects described in this way must be in a given order, whether temporally, spatially, sequentially, or in any other way.

[0057] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0058] Example:

[0059] A subsurface structure with a nonlinear inertial-compression type multi-stage self-resetting central column under three-dimensional seismic motion, such as... Figure 1As shown, it includes a top plate 1, a bottom plate 2, side walls 3, a multi-segment self-resetting column 4, and a nonlinear inertial capacitive self-resetting friction damper 5. The top plate 1, bottom plate 2, and side walls 3 form a rectangular cross-section of the underground space structure. Vertically segmented self-resetting columns 4 are arranged between the top plate 1 and the bottom plate 2.

[0060] like Figures 2 to 5 As shown, the top and bottom of the self-resetting column 4 are provided with reinforcement members 8. The reinforcement members 8 can be made of steel plate, high-strength concrete or composite material. In this embodiment, steel plate is selected. The purpose of the reinforcement members 8 is to reduce the damage to the top and bottom of the self-resetting column 4 during the swinging process.

[0061] Each segment of the self-resetting column 4 is connected in series with prestressed steel strands 7 and connected to the top plate 1 and the bottom plate 2.

[0062] The prestressed steel strand 7 is fixed to the contact surface of the self-resetting column 4 by the fastener 6. The fastener 6 includes a steel bearing plate, a fixing clamp and an adjusting bolt. The function of the steel bearing plate is to transmit the tension of the prestressed steel strand 7 to the column section. The function of the fixing clamp is to fix the prestressed steel strand 7. The function of the adjusting bolt is to adjust the prestress value of the prestressed steel strand 7.

[0063] In this embodiment, the self-resetting column 4 is provided with three segments, and four prestressed steel strands 7 are embedded in the self-resetting column 4. Two of them are connected to the middle self-resetting column 4, the lower self-resetting column 4 and the base plate 2, and the other two are connected to the middle self-resetting column 4, the upper self-resetting column 4 and the top plate 1.

[0064] Nonlinear capacitive self-resetting friction dampers 5 are vertically arranged on the outer side of the connection of the self-resetting column 4 of each segment. In this embodiment, two nonlinear capacitive self-resetting friction dampers 5 are vertically parallel and symmetrically arranged on both sides of the connection of the self-resetting column 4 of each segment.

[0065] like Figures 6 to 8 As shown, the nonlinear inertial capacitive self-resetting friction damper 5 includes a shaft 10, a clamping plate 12, and a rotating block 13. The rotating block 13 is held in the clamping plate 12. In this embodiment, four quarter-circle clamping plates 12 clamp two rotating blocks 13 in the middle. The rotating block 13 is sleeved on the shaft 10. The shaft 10 is connected to the self-resetting column 4.

[0066] The clamping plate 12 is provided with internal threads, and the rotating block 13 is provided with external threads. The rotating block 13 has a vertical non-equal diameter. In this embodiment, the two non-equal diameter rotating blocks 13 are symmetrically installed. The clamping plate 12 and the rotating block 13 are matched by threads, so that the rotating block 13 rotates along the threads inside the clamping plate 12, and the clamping plate 12 undergoes radial displacement.

[0067] The clamping plate 12 is provided with a non-internal thread contact surface, and the rotating block 13 is provided with a non-external thread contact surface. The mutual matching of the non-threaded contact surfaces between the clamping plate 12 and the rotating block 13 is the initial state.

[0068] A connecting rod is provided on the self-resetting column 4, and the shaft 10 is hinged to the connecting rod through the hinged connector 9;

[0069] The hinged connector 9 includes two steel rods and a set of hinge bolts;

[0070] A flywheel 11 is fitted on the outside of the clamping plate 12 on the shaft 10. In this embodiment, two flywheels 11 are symmetrically fitted on both sides of the clamping plate 12 on the shaft 10. The flywheels 11 rotate together with the rotating block 13.

[0071] The clamping plate 12 is wrapped with shape memory alloy (SMA) stranded wire 14. The shape memory alloy stranded wire 14 can be nickel-titanium-based shape memory alloy (Ni-Ti SMA) stranded wire, copper-based shape memory alloy (Cu SMA) stranded wire, or iron-based shape memory alloy (FeSMA) stranded wire. In this embodiment, nickel-titanium-based shape memory alloy stranded wire is selected. The clamping plate 12 and the rotating block 13 are engaged with each other by the radial force provided by the shape memory alloy stranded wire 14. At the same time, the deformation capacity of the shape memory alloy stranded wire 14 provides space for the clamping plate 12 to open and close radially and provides restoring force for the clamping plate 12.

[0072] A nonlinear inertial-capacitive multi-stage self-resetting method for three-dimensional seismic motion is proposed, which utilizes the underground structure of the aforementioned nonlinear inertial-capacitive multi-stage self-resetting column for three-dimensional seismic motion to perform multi-stage self-resetting. The specific steps are as follows:

[0073] When the underground space structure is subjected to earthquake, the top plate 1 and the bottom plate 2 undergo relative deformation, which in turn causes the self-resetting column 4 to sway.

[0074] The prestressed steel strands 7 of the series segmented self-resetting column 4 and the nonlinear inertial capacitive self-resetting friction dampers 5 installed on both sides of the connection of the self-resetting column 4 provide energy dissipation and restoring force for the self-resetting column 4.

[0075] The prestressed steel strand 7 is set with different prestresses in each segment of the self-resetting column 4 according to the swing sequence of the self-resetting column 4. The nonlinear inertial capacitive self-resetting friction damper 5 is set with different self-resetting and energy dissipation capabilities in each segment of the self-resetting column 4 according to the vibration reduction and energy dissipation requirements, thus realizing the segmented swing of the self-resetting column 4.

[0076] In this embodiment, the prestress values ​​of the prestressed steel strands 7 of each segment of the self-resetting column 4 are set sequentially from small to large according to the swing sequence of the self-resetting column 4. When the horizontal ground motion is applied, single-segment swing, two-segment swing, three-segment swing, etc. are realized according to the ground motion magnitude. This not only realizes the swing energy dissipation under the ground motion, but also realizes the graded response under different ground motion intensities.

[0077] The relative deformation of the external structure acts on the nonlinear inertial capacitive self-resetting friction damper 5 through the hinged connector 9 and the shaft 10. The rotation of the rotating block 13 along the thread causes the clamping plate 12 to undergo radial displacement and the flywheel 11 to rotate. At this time, part of the energy is dissipated through the inertial capacitive friction energy dissipation effect.

[0078] After the excitation of the external structure ends, the shape memory alloy strand 14 on the outside of the clamp 12 provides radial restoring force and also allows the clamp 12 to undergo radial opening and closing motion under the action of the rotating block 13. The restoring force pushes the rotating block 13 to return to the initial state along the thread. In this process, the restoring force acts on the self-resetting column 4 through the hinged connector 9 and the shaft 10, pushing the self-resetting column 4 to return to its original position and reducing its residual displacement.

[0079] By adjusting the roughness of the threaded contact surface between the clamping plate 12 and the rotating block 13, as well as the material properties of the shape memory alloy strand 14, the action threshold of the nonlinear inertial capacitive self-resetting friction damper 5 can be adjusted; it matches the prestress value of the prestressed steel strand 7, achieving dual energy consumption enhancement and multi-level self-resetting restoring force working in synergy.

[0080] When a horizontal seismic action is applied to an underground space structure, the segmented self-resetting column 4 begins to sway. Firstly, the swaying causes the prestressed steel strands 7 to undergo tensile deformation, providing the self-resetting column 4 with primary restoring force and damping energy dissipation. Secondly, the swaying causes vertical displacement of the bottom surface of the self-resetting column 4, which drives the movement of the rotating block 13 in the nonlinear inertial capacitive self-resetting friction damper 5. The relative movement between the rotating block 13 and the clamping plate 12, as well as the rotation of the flywheel 11, realizes the amplified inertial energy absorption and enhanced frictional energy dissipation based on the inertial capacitive element. At the same time, the thread design of the contact surface between the rotating block 13 and the clamping plate 12 and the shape memory alloy strands 14 on the outside of the clamping plate 12 provide the self-resetting column 4 with secondary restoring force.

[0081] When vertical seismic action is applied to underground space structures, the compression and tension between the segmented self-resetting columns 4 in the vertical distance can provide vertical displacement for the nonlinear inertial capacitive self-resetting friction damper 5, causing the rotating block 13 and the clamping plate 12 to generate amplified inertial energy absorption and enhanced frictional energy dissipation based on the inertial capacitive element. At the same time, the thread design of the contact surface between the rotating block 13 and the clamping plate 12 and the shape memory alloy stranded wire 14 on the outside of the clamping plate 12 provide additional vertical restoring force for the self-resetting column 4.

[0082] When the underground space structure is subjected to multidimensional seismic motion, the underground structure of the nonlinear inertial-capacitive multi-level self-resetting central column under the above-mentioned three-dimensional seismic motion will protect the safety of the underground space structure in the two forms of energy dissipation and restoring force mentioned above.

[0083] This invention significantly reduces the dynamic response of underground spatial structure systems under external excitation while achieving a graded response mechanism for small, medium, and large earthquakes. On the one hand, it enhances the practical value of inertial-capacity-enhanced self-resetting energy-dissipating self-resetting columns; on the other hand, it reduces the prefabrication and installation costs of these columns, and also facilitates post-earthquake component replacement and repair. Furthermore, the friction damper of the segmented inertial-capacity-enhanced self-resetting energy-dissipating self-resetting column achieves frictional energy dissipation and self-resetting under multidimensional seismic motion, enabling underground spatial structure systems to possess energy dissipation and self-resetting capabilities under multidimensional seismic motion, thus demonstrating significant potential for widespread application.

[0084] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.

Claims

1. An underground structure with a nonlinear inertial-compression type multi-stage self-resetting central column under three-dimensional seismic motion, characterized in that, The structure includes a top plate (1), a bottom plate (2), side walls (3), a multi-segment self-resetting column (4) and a nonlinear inertial capacitive self-resetting friction damper (5). The top plate (1), bottom plate (2) and side walls (3) constitute an underground space structure. Vertically segmented self-resetting columns (4) are arranged between the top plate (1) and the bottom plate (2). A nonlinear inertial capacitive self-resetting friction damper (5) is vertically arranged on the outside of the connection of the self-resetting column (4) of each segment. The nonlinear inertial capacitive self-resetting friction damper (5) includes a shaft (10), a clamping plate (12) and a rotating block (13). The clamping plate (12) holds the rotating block (13), which is sleeved on the shaft (10). The shaft (10) is connected to the self-resetting column (4). The clamp (12) is wrapped with shape memory alloy stranded wire (14). The clamping plate (12) is provided with an internal thread, and the rotating block (13) is provided with an external thread. The rotating block (13) is not of equal diameter in the vertical direction. The clamping plate (12) and the rotating block (13) are matched by threads, so that the rotating block (13) rotates along the thread inside the clamping plate (12), and the clamping plate (12) undergoes radial displacement. A connecting rod is provided on the self-resetting column (4), and the shaft (10) is hinged to the connecting rod through the hinged connector (9).

2. The underground structure of a nonlinear inertial-compression type multi-stage self-resetting central column under three-dimensional seismic motion according to claim 1, characterized in that, The clamping plate (12) is provided with a non-internal thread contact surface, and the rotating block (13) is provided with a non-external thread contact surface. The mutual matching of the non-threaded contact surfaces between the clamping plate (12) and the rotating block (13) is taken as the initial state.

3. The underground structure of a nonlinear inertial-compressive multi-stage self-resetting central column under three-dimensional seismic motion according to claim 1, characterized in that, A flywheel (11) is fitted on the outside of the clamping plate (12) on the shaft (10), and the flywheel (11) rotates together with the rotating block (13).

4. The underground structure of a nonlinear inertial-compression type multi-stage self-resetting central column under three-dimensional seismic motion according to claim 1, characterized in that, The self-resetting columns (4) of each segment are connected in series by prestressed steel strands (7) and connected to the top plate (1) and the bottom plate (2).

5. The underground structure of a nonlinear inertial-compressive multi-stage self-resetting central column under three-dimensional seismic motion according to claim 4, characterized in that, The prestressed steel strand (7) is fixed to the contact surface of the self-resetting column (4) by a fastener (6).

6. The underground structure of a nonlinear inertial-compressive multi-stage self-resetting central column under three-dimensional seismic motion according to claim 4, characterized in that, The prestressed steel strand (7) is required to set different prestresses on the self-resetting column (4) of each segment according to the swing sequence of the self-resetting column (4). The nonlinear inertial capacitive self-resetting friction damper (5) is set with different self-resetting and energy dissipation capabilities on the self-resetting column (4) of each segment according to the vibration reduction and energy dissipation requirements, so as to realize the segmented swing of the self-resetting column (4).

7. The underground structure of a nonlinear inertial-compressive multi-stage self-resetting central column under three-dimensional seismic motion according to claim 6, characterized in that, By adjusting the roughness of the threaded contact surface between the clamping plate (12) and the rotating block (13) and the material properties of the shape memory alloy strand (14), the action threshold of the nonlinear inertial capacitive self-resetting friction damper (5) is adjusted; it matches the prestress value of the prestressed steel strand (7) to achieve dual energy consumption enhancement and multi-level self-resetting restoring force working together.

8. The underground structure of a nonlinear inertial-compression type multi-stage self-resetting central column under three-dimensional seismic motion according to claim 1, characterized in that, The self-resetting column (4) is provided with reinforcement parts (8) at the top and bottom of the column.

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