Semi-active tuned mass damper based on intelligent material

Abstract

The invention provides a semi-active tuned mass damper based on an intelligent material. The semi-active tuned mass damper comprises a passive control part, an intelligent control part, a first-stage vibration reduction part, a second-stage vibration reduction part and a health monitoring part, and the intelligent control part controls the first-stage vibration reduction part, the second-stage vibration reduction part and the health monitoring part in a unified mode; according to the tuned mass damper, bidirectional vibration control of a building structure can be achieved, the vibration response of the tuned mass damper and a main structure is monitored in real time, and semi-active control over an intelligent material is started after data are collected and analyzed through a computer control system.

Description

Technical Field

[0001] The invention belongs to the technical fields of civil engineering and vibration control, and in particular relates to a semi-active tuned mass damper based on smart materials. Background Art

[0002] With the development of structural design and construction technology, building structures have become taller and more slender. However, high-rise buildings are very sensitive to the dynamic response under natural disasters due to their soft body, low natural frequency and damping ratio. Earthquakes are one of the most destructive and dangerous natural disasters. How to protect the safety of building structures under earthquakes has always been a research hotspot for scholars in the world's civil engineering community. With people's higher requirements for the safety of building structures, it is challenging and valuable to conduct research on intelligent disaster prevention and mitigation of structures under earthquakes.

[0003] Tuned Mass Damper (TMD) is a traditional structural vibration control device. A tuned mass damper is a single-degree-of-freedom vibration absorber composed of a mass unit, a stiffness unit, and a damping unit. It can adjust its natural frequency to be the same as a certain frequency that the structure needs to control. When the external excitation acts on the structure to cause horizontal vibration, the tuned mass damper controls the vibration of the structure by applying an inertial force in the opposite direction to the structure and consumes the vibration energy through the damping unit. However, the traditional passive tuned mass damper has the disadvantage of being sensitive to frequency tuning. When its frequency deviates from the structural frequency, its control effect will be significantly reduced. In order to improve the multi-hazard control effect of the tuned mass damper and make it have a certain degree of adaptability, it is very meaningful to study a semi-active tuned mass damper that can spontaneously change parameters to improve the energy dissipation and shock absorption effect.

[0004] Actual natural disasters are bidirectional inputs, while conventional tuned mass dampers can only control unidirectional structural vibrations. In order to control the bidirectional seismic response of the structure, one method is to arrange a tuned mass damper in both directions in the plane, but this will increase the amount of mechanical devices, increase economic investment, increase the space occupied by the building, and also bring a greater vertical load burden to the structure. In summary, in order to protect the safety of building structures under the action of bidirectional disasters, and to have the advantages of saving damper electromechanical devices and saving electricity, it is necessary to propose a bidirectional semi-active tuned mass damper for energy dissipation and shock absorption. Summary of the invention

[0005] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a semi-active tuned mass damper based on smart materials to improve the bidirectional energy dissipation and shock absorption performance.

[0006] The objective of the present invention is achieved through the following technical solutions:

[0007] A semi-active tuned mass damper based on smart materials, comprising: a mass block, a high-strength steel ball roller, a sliding frame, a lower connecting plate and a steel column bracket, wherein the lower connecting plate is connected to the floor of a building structure by welding or bolts, the sliding frame is placed on the lower connecting plate, a piezoelectric ceramic sliding surface is placed on the upper surface of the sliding frame, the bottom surface of the mass block is connected to the high-strength steel ball roller through a bearing, the high-strength steel ball roller is placed on the upper surface of the sliding frame and can roll freely in both directions, a magnetorheological elastomer spring is arranged between the mass block and the sliding frame, and the two ends of the magnetorheological elastomer spring are respectively connected to the mass block and the sliding frame. The steel column bracket is connected to the edge of the lower connecting plate by welding or bolts, the shape memory alloy spring passes through the electrorheological damper and the two ends of the shape memory alloy spring are respectively connected to the steel column bracket (7) and the sliding frame (4) by reserved fasteners, the three-dimensional vibration sensor I is adsorbed on the side of the steel column bracket to measure the X, Y, and Z three-dimensional vibration response of the steel column bracket, the three-dimensional vibration sensor II is adsorbed on the side of the mass block to measure the X, Y, and Z three-dimensional vibration response of the mass block, and the three-dimensional vibration sensor I and the three-dimensional vibration sensor II are respectively connected to the computer control system by wired or wireless transmission.

[0008] The smart materials refer to the piezoelectric ceramic sliding surface, magnetorheological elastomer spring, electrorheological damper and shape memory alloy spring.

[0009] The mass block, high-strength steel ball roller, sliding frame and lower connecting plate form the passive control part of the semi-active tuned mass damper.

[0010] The three-way vibration sensor I, the three-way vibration sensor II and the computer control system form the intelligent control part of the semi-active tuned mass damper. The computer control system obtains the bidirectional optimal frequency and damping ratio of the semi-active tuned mass damper by analyzing and processing the sensing signals of the three-way vibration sensor I and the three-way vibration sensor II, and then starts the semi-active control of the intelligent material.

[0011] The piezoelectric ceramic sliding surface and the magnetorheological elastic spring form a first-stage vibration reduction part of the semi-active tuned mass damper. The piezoelectric ceramic sliding surface changes its own material properties under the drive of the computer control system to improve the vibration reduction performance of the damper. The magnetorheological elastic spring changes the amount of current and the magnetic field under the drive of the computer control system to adjust the frequency and damping ratio of the damper. In the first-stage vibration reduction part, the piezoelectric ceramic sliding surface is used to realize intelligent control of the mass block to improve its bidirectional energy dissipation and shock absorption performance in the plane, and the magnetorheological elastic spring is used as the stiffness and damping unit of the mass block. The computer control system can change the amount of current and the magnetic field of the magnetorheological elastic spring, thereby adjusting the frequency and damping ratio of the damper and improving its bidirectional vibration reduction effect.

[0012] The steel column support, the electrorheological damper and the shape memory alloy spring form the two-stage vibration reduction part of the semi-active tuned mass damper. The electrorheological damper changes the amount of current to change the damping ratio under the drive of the computer control system, and the shape memory alloy spring changes the amount of current to change the stiffness and damping ratio under the drive of the computer control system, thereby jointly adjusting the stiffness and damping ratio of the mass block and the sliding frame as a whole under large vibration in real time, so as to achieve the function of controlling the dynamic response of the structure, reducing the stroke and limit of the damper. In the two-stage vibration reduction part, the mass block will slide on the lower connecting plate together with the sliding frame, and the semi-active restoring force and damping force will be provided by the electrorheological damper and the shape memory alloy spring, which can reduce the stroke and limit of the damper while improving the vibration reduction effect.

[0013] The three-way vibration sensor I, the three-way vibration sensor II and the computer control system form the health monitoring part of the semi-active tuned mass damper. The real-time vibration signals of the semi-active tuned mass damper and the building structure are stored, transmitted and analyzed in real time by the health monitoring part to ensure the normal operation and safety of the building structure and the tuned mass device.

[0014] The steel column bracket, the electrorheological damper and the shape memory alloy spring each form a set of kits, and the semi-active tuned mass damper is provided with 4 to 8 sets of the kits, and each kit is evenly distributed and rotated around the sliding frame.

[0015] The three-axis sensor used may be an acceleration sensor, a velocity sensor or a displacement sensor.

[0016] The semi-active tuned mass damper based on smart materials proposed by the present invention adopts the above solution, and has the following beneficial effects:

[0017] First, the tuned mass damper of the present invention can simultaneously control the bidirectional vibration of a high-rise building in a plane, and has the advantages of saving building space, saving the amount of dampers, reducing concentrated loads on floors and saving costs.

[0018] Second, the tuned mass damper of the present invention can start sliding under relatively small wind vibrations, and changes the mechanical properties of the rolling surface through the piezoelectric ceramic sliding surface to change the frequency and damping ratio of the damper, and provides semi-active restoring force and damping force through the magnetorheological elastomer spring to improve its bidirectional energy dissipation and shock absorption performance.

[0019] Third, the tuned mass damper of the present invention has better bidirectional vibration control performance than the traditional tuned mass damper because it can adjust its own bidirectional frequency and damping ratio in real time.

[0020] Fourth, under large vibration, the tuned mass damper of the present invention can improve its control effect through the structural forms such as the electrorheological damper, the shape memory alloy spring, and the sliding frame sliding together, reduce the stroke of the mass block, and play a better limiting role.

[0021] Fifth, the real-time vibration signals of the tuned mass damper and the main structure of the present invention are stored, transmitted and analyzed in real time by the health monitoring part to ensure the normal operation and safety of the main structure and the tuned mass damper. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic structural diagram of the semi-active tuned mass damper based on smart materials of the present invention.

[0023] Figure 2 It is a top view of a preferred embodiment of the semi-active tuned mass damper based on smart materials of the present invention.

[0024] Figure 3 It is a top view of another preferred embodiment of the semi-active tuned mass damper based on smart materials of the present invention.

[0025] Figure 4 This is a flow chart of the control algorithm of the semi-active tuned mass damper based on smart materials of the present invention.

[0026] Figure numerals: 1-mass block, 2-high-strength steel ball roller, 3-piezoelectric ceramic sliding surface, 4-sliding frame, 5-lower connecting plate, 6-magnetorheological elastomer spring, 7-steel column bracket, 8-electrorheological damper, 9-shape memory alloy spring, 10-computer control system, 11-three-way vibration sensor I and 12-three-way vibration sensor II. DETAILED DESCRIPTION

[0027] The present invention is further described below in conjunction with the accompanying drawings and embodiments, but the embodiments are not intended to limit the present invention. All similar structures and similar variations of the present invention should be included in the protection scope of the present invention.

[0028] The semi-active tuned mass damper based on smart materials of the present invention comprises: a passive control part, an intelligent control part, a first-stage vibration reduction part, a second-stage vibration reduction part and a health monitoring part, wherein the intelligent control part uniformly controls the first-stage vibration reduction part, the second-stage vibration reduction part and the health monitoring part.

[0029] Specifically include: mass block 1, high-strength steel ball roller 2, sliding frame 4, lower connecting plate 5 and steel column bracket 7, the lower connecting plate 5 is connected to the floor of the building structure by welding or bolts, the sliding frame 4 is placed on the lower connecting plate 5, the upper surface of the sliding frame 4 is placed with a piezoelectric ceramic sliding surface 3, the bottom surface of the mass block 1 is connected to the high-strength steel ball roller 2 through a bearing, the high-strength steel ball roller 2 is placed on the upper surface of the sliding frame 4 and can roll freely in both directions, the magnetorheological elastomer spring 6 is arranged between the mass block 1 and the sliding frame 4, and the two ends of the magnetorheological elastomer spring 6 are respectively clamped with the mass block 1 and the sliding frame 4, the steel column bracket 7 It is connected to the edge of the lower connecting plate 5 by welding or bolts, the shape memory alloy spring 9 passes through the electrorheological damper 8, and the two ends of the shape memory alloy spring 9 are respectively connected to the steel column bracket 7 and the sliding frame 4 through reserved fasteners, the three-way vibration sensor 11 is adsorbed on the side of the steel column bracket 7 to measure the X, Y, and Z three-way vibration response of the steel column bracket 7, the three-way vibration sensor 12 is adsorbed on the side of the mass block 1 to measure the X, Y, and Z three-way vibration response of the mass block 1, and the three-way vibration sensor 11 and the three-way vibration sensor 12 are respectively connected to the computer control system 10 through wired or wireless transmission.

[0030] The smart material described in the present invention refers to a piezoelectric ceramic sliding surface 3 , a magnetorheological elastomer spring 6 , an electrorheological damper 8 and a shape memory alloy spring 9 .

[0031] Among them, one steel column bracket 7, one electrorheological damper 8 and one shape memory alloy spring 9 each form a set of kits, and the semi-active tuned mass damper is provided with 4 to 8 sets of the kits, and each kit is evenly distributed and rotated around the sliding frame 4.

[0032] like Figure 2 In a preferred embodiment of the present invention, four sets of steel column brackets 7, electrorheological dampers 8 and shape memory alloy springs 9 are evenly distributed and rotated around the sliding frame 4. In each set of components, one end of the shape memory alloy spring 9 is connected to the steel column bracket 7 provided at a corner of the lower connecting plate 5, and the other end is connected to a corner farther away from the sliding frame 4. The four sets of components are connected in sequence, so as to be evenly distributed and rotated around the sliding frame 4.

[0033] like Figure 3 In another preferred embodiment of the present invention shown, eight sets of steel column brackets 7, electrorheological dampers 8 and shape memory alloy springs 9 are evenly distributed and rotated around the sliding frame 4. In addition to being arranged at the four corners of the lower connecting plate 5, the steel column bracket 7 is also arranged in the middle between two corners; accordingly, fasteners are also reserved in the middle of the two corners of the sliding frame 4. If one end of the shape memory alloy spring 9 is connected to the steel column bracket 7 at the corner, the other end is connected to the middle of the sliding frame 4; accordingly, if one end of the shape memory alloy spring 9 is connected to the steel column bracket 7 between the two corners, the other end is connected to a corner farther away from the sliding frame 4. The eight sets of kits are connected in sequence, so as to be evenly distributed and rotated around the sliding frame 4.

[0034] The three-way vibration sensor 11 and the three-way vibration sensor 12 used may be an acceleration sensor, a velocity sensor or a displacement sensor.

[0035] Passive control part

[0036] The passive control part includes: a mass block 1, a high-strength steel ball roller 2, a sliding frame 4 and a lower connecting plate 5. The mass block 1 can smoothly roll in both directions in a plane through the high-strength steel ball roller 2 to achieve bidirectional vibration control of the building structure.

[0037] Intelligent control part

[0038] The intelligent control part includes: a computer control system 10, a three-way vibration sensor 11 and a three-way vibration sensor 12. The computer control system 10 can monitor the vibration response of the tuned mass damper and the building structure in real time. By analyzing and processing the sensor signals of the three-way vibration sensor 11 and the three-way vibration sensor 12, the phase angle of the sensor signal is solved in real time, and the derivative and the upper and lower limits of the window control are calculated, and the instantaneous optimal frequency is generally 0.1-1.0Hz; the computer control system 10 calculates the optimal damping ratio by integrating the algorithm based on the minimum amplitude of the acceleration vibration of the building structure as the optimization target, which is generally 0-12%. Then, the semi-active control part is fed back respectively, the semi-active control of the intelligent material is started, and the stiffness and damping are adjusted in real time respectively. The specific method for the computer control system to process and calculate the collected data does not belong to the technical problem to be solved by the present invention, and belongs to the prior art known to those skilled in the art, and will not be repeated here.

[0039] First stage vibration reduction part

[0040] The first-stage vibration reduction part includes: a piezoelectric ceramic sliding surface 3 and a magnetorheological elastic body spring 6. The piezoelectric ceramic sliding surface 3 changes its own material properties under the drive of the computer control system 10 to improve the vibration reduction performance of the damper, and the magnetorheological elastic body spring 6 changes the amount of current and the magnetic field under the drive of the computer control system 10 to adjust the frequency and damping ratio of the damper. In the first-stage vibration reduction part, the piezoelectric ceramic sliding surface 3 is used to realize the intelligent control of the mass block 1 to improve its bidirectional energy dissipation and shock absorption performance in the plane, and the magnetorheological elastic body spring 6 is used as the stiffness and damping unit of the mass block 1. The computer control system 10 can change the amount of current and the magnetic field of the magnetorheological elastic body spring 6, thereby adjusting the frequency and damping ratio of the damper and improving its bidirectional vibration reduction effect.

[0041] Second stage vibration reduction

[0042] The second-stage vibration reduction part includes: a steel column bracket 7, an electrorheological damper 8 and a shape memory alloy spring 9. The electrorheological damper 8 changes the amount of current to change the damping ratio under the drive of the computer control system 10, and the shape memory alloy spring 9 changes the amount of current to change the stiffness and damping ratio under the drive of the computer control system 10, thereby jointly adjusting the stiffness and damping ratio of the mass block 1 and the sliding frame 4 as a whole under large vibration in real time, so as to achieve the function of controlling the dynamic response of the structure, reducing the stroke and limit of the damper. In the second-stage vibration reduction part, the mass block 1 will slide on the lower connecting plate 5 together with the sliding frame 4, and the electrorheological damper 8 and the shape memory alloy spring 9 will jointly provide semi-active restoring force and damping force, which can reduce the stroke and limit of the damper while improving the vibration reduction effect.

[0043] Health monitoring part

[0044] The health monitoring part includes: a computer control system 10, a three-way vibration sensor 11 and a three-way vibration sensor 12. The real-time vibration signals of the semi-active tuned mass damper and the building structure are stored, transmitted and analyzed in real time by the health monitoring part to ensure the normal operation and safety of the building structure and the tuned mass damper.

[0045] The above description is only a description of the preferred embodiments of the present invention, and is not intended to limit the scope of the present invention. Any changes or modifications made by any person skilled in the art based on the above disclosed technical contents shall be regarded as equivalent effective embodiments and shall fall within the scope of protection of the technical solution of the present invention.

Claims

1. A semi-active tuned mass damper based on smart materials, characterized in that: include: A mass block (1), a high-strength steel ball roller (2), a sliding frame (4), a lower connecting plate (5) and a steel column bracket (7), wherein the lower connecting plate (5) is connected to the floor of a building structure by welding or bolts, the sliding frame (4) is placed on the lower connecting plate (5), a piezoelectric ceramic sliding surface (3) is placed on the upper surface of the sliding frame (4), the bottom surface of the mass block (1) is connected to the high-strength steel ball roller (2) via a bearing, the high-strength steel ball roller (2) is placed on the upper surface of the sliding frame (4) and can roll freely in both directions, a magnetorheological elastomer spring (6) is arranged between the mass block (1) and the sliding frame (4), and the two ends of the magnetorheological elastomer spring (6) are respectively clamped to the mass block (1) and the sliding frame (4), and the The steel column bracket (7) is connected to the edge of the lower connecting plate (5) by welding or bolts, the shape memory alloy spring (9) passes through the electrorheological damper (8) and the two ends of the shape memory alloy spring (9) are respectively connected to the steel column bracket (7) and the sliding frame (4) by reserved fasteners, the three-dimensional vibration sensor I (11) is adsorbed on the side of the steel column bracket (7) to measure the X, Y, and Z three-dimensional vibration response of the steel column bracket (7), the three-dimensional vibration sensor II (12) is adsorbed on the side of the mass block (1) to measure the X, Y, and Z three-dimensional vibration response of the mass block (1), and the three-dimensional vibration sensor I (11) and the three-dimensional vibration sensor II (12) are respectively connected to the computer control system (10) by wired or wireless transmission; in: The mass block (1), the high-strength steel ball roller (2), the sliding frame (4) and the lower connecting plate (5) form a passive control part of the semi-active tuned mass damper; The three-way vibration sensor I (11), the three-way vibration sensor II (12) and the computer control system (10) form an intelligent control part of the semi-active tuned mass damper, and the computer control system (10) obtains the bidirectional optimal frequency and damping ratio of the semi-active tuned mass damper by analyzing and processing the sensing signals of the three-way vibration sensor I (11) and the three-way vibration sensor II (12); The piezoelectric ceramic sliding surface (3) and the magnetorheological elastic body spring (6) form a first-stage vibration reduction part of the semi-active tuned mass damper. The piezoelectric ceramic sliding surface (3) changes its own material properties under the drive of the computer control system (10) to improve the vibration reduction performance of the damper. The magnetorheological elastic body spring (6) changes the amount of current and the magnetic field under the drive of the computer control system (10) to adjust the frequency and damping ratio of the damper. The steel column support (7), the electrorheological damper (8) and the shape memory alloy spring (9) form a two-stage vibration reduction part of the semi-active tuned mass damper. The electrorheological damper (8) changes the amount of current flow to change the damping ratio under the drive of the computer control system (10). The shape memory alloy spring (9) changes the amount of current flow to change the stiffness and damping ratio under the drive of the computer control system (10). Thus, the stiffness and damping ratio of the mass block (1) and the sliding frame (4) as a whole are jointly adjusted in real time under large vibration, so as to achieve the effect of controlling the dynamic response of the structure, reducing the stroke of the damper and limiting the position. The three-way vibration sensor I (11), the three-way vibration sensor II (12) and the computer control system (10) form a health monitoring part of the semi-active tuned mass damper, and the real-time vibration signals of the semi-active tuned mass damper and the building structure are stored, transmitted and analyzed in real time by the health monitoring part.

2. The semi-active tuned mass damper according to claim 1, characterized in that: The steel column support (7), the electrorheological damper (8) and the shape memory alloy spring (9) each form a set of components, and the semi-active tuned mass damper is provided with 4 to 8 sets of the components, and each component is evenly distributed and rotated around the sliding frame (4).

3. The semi-active tuned mass damper according to claim 1, characterized in that: The three-way vibration sensor I (11) and the three-way vibration sensor II (12) are acceleration sensors, velocity sensors or displacement sensors.

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