Shape memory alloy damper and high arch dam shock absorber

Abstract

The invention relates to the technical field of shock resistance and vibration reduction, in particular to a shape memory alloy damper and a high arch dam shock absorber. According to the shape memory alloy damper, the shape memory alloy wires in the shape memory alloy damper can be lengthened no matter the shape memory alloy damper is pulled or pressed, the utilization efficiency of the shape memory alloy wires is effectively improved, the shape memory alloy damper is applied to high arch dam damping, and the damping effect is greatly improved.

Description

Technical Field

[0001] The invention relates to the technical field of anti-seismic vibration reduction, in particular to a shape memory alloy damper and a high arch dam shock absorber. Background Art

[0002] Since the 20th century, people have invested a lot of energy in the anti-seismic and vibration reduction performance of buildings, and have achieved remarkable results. One of the most effective results is the "structural protection system". People have jumped out of the traditional concept of strengthening beams, columns, and walls to improve the ability to resist vibration, and combined with the dynamic performance of the structure, they have cleverly avoided or reduced the damage of earthquakes and wind. Foundation isolation, energy dissipation using dampers, energy dissipation systems, mass resonance damping systems on the roofs of high-rise buildings, and active control shock absorption systems have all entered engineering practice, and some of them have become indispensable protective measures to reduce vibration. Especially for earthquakes that are difficult to predict and multi-dimensional vibrations whose damage mechanisms are not very clear, the protection systems of these structures become even more important.

[0003] In recent years, dampers made of viscoelastic materials and viscous fluids have appeared. These dampers have a certain vibration reduction effect on structures. The characteristics of this type of damping are that the magnitude of its damping force is mainly related to the speed of structural vibration, but not to the amplitude of structural deformation, and in engineering applications, it is necessary to solve the characteristics of durability, anti-leakage or anti-corrosion.

[0004] An important property of shape memory alloys is pseudo-elasticity (also known as superelasticity), which means that under the action of external forces, shape memory alloys have a much greater deformation recovery ability than general metals, that is, the large strain generated during loading will recover with unloading. The shape memory alloy damper made using this property of shape memory alloys is characterized in that as the displacement increases, its vibration reduction and energy dissipation effect will also increase, thereby improving the seismic performance of the structure. On the other hand, shape memory alloys have good durability, good corrosion resistance, and a long service life. Existing shape memory alloy dampers are generally only allowed to be subjected to unidirectional deformation (usually tension), which restricts the utilization efficiency of shape memory alloys. Summary of the invention

[0005] Therefore, the technical problem to be solved by the present invention is to overcome the problem of restricted utilization efficiency of shape memory alloys in the prior art.

[0006] In order to solve the above technical problems, the present invention provides a shape memory alloy damper, comprising:

[0007] The fixed body is provided with a first groove with one end closed and the other end open to fit the sliding body, the closed end of the fixed body is provided with a first lug, and two first sliding grooves are provided on both sides of the left and right sides of the first groove;

[0008] The sliding body is placed in the first groove, a first portion of the sliding body close to the closed end of the fixed body is provided with a second groove, a second portion away from the closed end of the fixed body is provided with a second lug, and two second slide grooves with the same length as the first slide groove are provided on both sides of the left and right sides of the second groove;

[0009] The first connecting rod and the second connecting rod connected by winding a shape memory alloy wire are placed laterally on the first slide groove and the second slide groove, so that the first slide groove and the second slide groove on the fixed body and the sliding body remain aligned in pairs, and the shape memory alloy wire remains stretched and unstressed.

[0010] Preferably, after the first sliding grooves and the second sliding grooves on the fixed body and the sliding body are kept aligned in pairs, the sliding body is at a certain distance from the closed end of the fixed body.

[0011] Preferably, the first chute includes a first left sub-chute and a first right sub-chute, and the second chute includes a second left sub-chute and a second right sub-chute.

[0012] Preferably, when the fixed body remains stationary and the second lug is pulled:

[0013] The sliding body moves toward the side away from the closed end of the fixed body, the first connecting rod is constrained by the right limit piece on the first left sub-slot and remains stationary, the second connecting rod is constrained by the left limit piece on the second right sub-slot, and moves together with the sliding body in the direction away from the closed end of the fixed body, and the shape memory alloy wire is stretched.

[0014] Preferably, when the fixed body remains stationary, the shape memory alloy wire is stretched to generate a restoring force so that the second connecting rod is subjected to the tension of the shape memory alloy wire:

[0015] The first connecting rod is constrained by the right limit piece on the first left sub-slide groove and remains stationary. The left limit piece on the second right sub-slide groove is acted upon by the thrust of the second connecting rod, driving the sliding body to move toward the closed end of the fixed body, and the shape memory alloy wire returns to its initial state.

[0016] Preferably, when the fixed body remains stationary and the second lug is pressed:

[0017] The sliding body moves toward the side close to the closed end of the fixed body, and the first connecting rod is constrained by the right limit piece on the second left sub-slide groove. As the sliding body moves toward the direction close to the closed end of the fixed body, the shape memory alloy wire is stretched, and the second connecting rod is constrained by the left limit piece on the first right sub-slide groove and remains stationary.

[0018] Preferably, when the fixed body remains stationary, the shape memory alloy wire generates a restoring force after being compressed so that the first connecting rod is subjected to the tension of the shape memory alloy wire:

[0019] The second connecting rod is constrained by the left limit piece on the first right sub-slide groove and remains stationary. The right limit piece on the second left sub-slide groove is acted upon by the thrust of the first connecting rod, driving the sliding body to move in a direction away from the closed end of the fixed body, and the shape memory alloy wire returns to its initial state.

[0020] Preferably, the shape memory alloy damper further includes a temperature adjustment unit, and the temperature adjustment unit includes:

[0021] power supply;

[0022] a thermistor connected in parallel with the power supply;

[0023] a variable resistor connected in parallel with the power supply, wherein the resistance value of the variable resistor is set to the resistance value of the thermistor at the optimum temperature of the shape memory alloy;

[0024] A cooling branch includes a fan connected in series with the cathode of the first diode;

[0025] A heating branch circuit includes a heating resistor wire connected in series with the anode of the second diode;

[0026] The temperature-lowering branch and the temperature-increasing branch are connected in parallel between the thermistor and the variable resistor.

[0027] Preferably, the working process of the temperature regulating unit includes:

[0028] When the ambient temperature is the optimum temperature, the resistance of the branch where the variable resistor is located is the same as that of the branch where the thermistor is located, no current flows through the fan and the heating resistor, and the fan and the heating resistor do not work;

[0029] When the ambient temperature is higher than the optimum temperature, the resistance values ​​of the branch where the variable resistor is located and the branch where the thermistor is located differ, the current is connected to the cooling branch, and the fan starts to work to cool the environment until the ambient temperature reaches the optimum temperature;

[0030] When the ambient temperature is lower than the optimum temperature, there is a difference in the resistance value between the branch where the variable resistor is located and the branch where the thermistor is located. The current is connected to the heating branch, and the heating resistor starts to work to heat the environment until the ambient temperature reaches the optimum temperature.

[0031] The present invention also provides a high arch dam shock absorber, comprising the shape memory alloy damper as described above.

[0032] The above technical solution of the present invention has the following advantages compared with the prior art:

[0033] The shape memory alloy damper described in the present invention allows the internal shape memory alloy wire to be elongated regardless of whether it is under tension or compression, thereby effectively improving the utilization efficiency of the shape memory alloy wire. Applying it to high arch dam shock absorption greatly improves the shock absorption performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to make the content of the present invention more clearly understood, the present invention is further described in detail below according to specific embodiments of the present invention in conjunction with the accompanying drawings, wherein:

[0035] Figure 1 It is a structural schematic diagram of a shape memory alloy damper provided by the present invention;

[0036] Figure 2 is a structural schematic diagram of a shape memory alloy damper provided by an embodiment of the present invention;

[0037] Figure 3 It is a schematic diagram of the application of the shape memory alloy damper provided by the present invention to high arch dam shock absorption. DETAILED DESCRIPTION

[0038] The core of the present invention is to provide a shape memory alloy damper and a high arch dam shock absorber, which effectively improves the utilization efficiency of shape memory alloy wire and applies it to high arch dam shock absorption, greatly improving the shock absorption efficiency.

[0039] In order to enable those skilled in the art to better understand the scheme of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0040] Please refer to Figure 1 , Figure 1 This is a structural schematic diagram of a shape memory alloy damper provided by the present invention; the specific structure includes:

[0041] The fixed body 1 is provided with a first groove with one end closed and the other end open to fit the sliding body, the closed end of the fixed body is provided with a first lug 12, and two first sliding grooves 11 are provided on both sides of the left and right sides of the first groove;

[0042] The sliding body 2 is placed in the first groove, the first part of the sliding body close to the closed end of the fixed body is provided with a second groove, the second part away from the closed end of the fixed body is provided with a second lug 22, and the left and right sides of the second groove are provided with two second slide grooves 21 with the same length as the first slide groove;

[0043] The first connecting rod 31 and the second connecting rod 32 connected by winding the shape memory alloy wire 33 are placed horizontally on the first slide groove and the second slide groove, so that the first slide groove and the second slide groove on the fixed body and the sliding body remain aligned in pairs, and the shape memory alloy wire remains stretched and unstressed.

[0044] Based on the above embodiments, after the first sliding grooves and the second sliding grooves on the fixed body and the sliding body are kept aligned in pairs, the sliding body is at a certain distance from the closed end of the fixed body.

[0045] Based on the above embodiment, the first chute includes a first left sub-chute 11a and a first right sub-chute 11b, and the second chute includes a second left sub-chute 21a and a second right sub-chute 21b.

[0046] Based on the above embodiments, assuming that the fixed body remains stationary, when the second lug is pulled:

[0047] The sliding body moves toward the side away from the closed end of the fixed body, the first connecting rod is constrained by the right limit piece on the first left sub-slot and remains stationary, the second connecting rod is constrained by the left limit piece on the second right sub-slot, and moves together with the sliding body in the direction away from the closed end of the fixed body, and the shape memory alloy wire is stretched.

[0048] The shape memory alloy wire generates a restoring force after being stretched, so that the second connecting rod is subjected to the tension of the shape memory alloy wire:

[0049] The first connecting rod is constrained by the right limit piece on the first left sub-slide groove and remains stationary. The left limit piece on the second right sub-slide groove is acted upon by the thrust of the second connecting rod, driving the sliding body to move toward the closed end of the fixed body, and the shape memory alloy wire returns to its initial state.

[0050] Based on the above embodiment, assuming that the fixed body remains stationary, when the fixed body remains stationary and the second lug is pressed:

[0051] The sliding body moves toward the side close to the closed end of the fixed body, and the first connecting rod is constrained by the right limit piece on the second left sub-slide groove. As the sliding body moves toward the direction close to the closed end of the fixed body, the shape memory alloy wire is stretched, and the second connecting rod is constrained by the left limit piece on the first right sub-slide groove and remains stationary.

[0052] The shape memory alloy wire generates a restoring force after being compressed, so that the first connecting rod is subjected to the tension of the shape memory alloy wire:

[0053] The second connecting rod is constrained by the left limit piece on the first right sub-slide groove and remains stationary. The right limit piece on the second left sub-slide groove is acted upon by the thrust of the first connecting rod, driving the sliding body to move in a direction away from the closed end of the fixed body, and the shape memory alloy wire returns to its initial state.

[0054] The shape memory alloy damper provided by the present invention has a shape memory alloy wire that will be elongated under tension and compression, which effectively improves the utilization efficiency of the shape memory alloy. After the shape memory alloy wire is elongated, a force (i.e., a restoring force) will be generated to restore the shape memory alloy damper as a whole to its initial state. During the elongation and recovery of the shape memory alloy wire, due to the pseudo-elasticity of the shape memory alloy material, its stress-strain curve is not linear, and the stress-strain curves of the loading and unloading processes do not completely overlap, which will generate energy consumption, thereby enabling the controlled structure to achieve the effect of vibration reduction and energy dissipation.

[0055] Based on the above embodiments, for shape memory alloys, when the external temperature fluctuates, its vibration reduction performance is easily affected. Figure 2 The present invention adds a temperature adjustment unit to the shape memory alloy damper, which is used to adjust the temperature of the environment in which the shape memory alloy wire is located, so that the shape memory alloy wire can exert the maximum vibration reduction performance. The temperature adjustment unit includes a power supply, a thermistor, a variable resistor, a fan, a heating resistor, a first diode and a second diode. The thermistor and the variable resistor are respectively connected in parallel with the power supply, the fan is connected in series with the negative electrode of the first diode to form a cooling branch, the heating resistor is connected in series with the positive electrode of the second diode to form a heating branch, the cooling branch and the heating branch are connected in parallel between the thermistor and the variable resistor, and the resistance value of the variable resistor is the resistance value of the thermistor at the optimum temperature of the shape memory alloy.

[0056] For shape memory alloys of different materials, the temperature range in which they exhibit superelasticity is also different. For the common TiNi shape memory alloy, the optimum temperature is usually between 18 and 35 degrees Celsius. The resistance value of the variable resistor 43 in the temperature adjustment unit 4 is set to the resistance value of the thermistor 42 at the optimum temperature. At this time, when the ambient temperature is the optimum temperature, the resistance value of the variable resistor 43 is the same as the resistance value of the thermistor 42. Therefore, the branch where the variable resistor 43 is located is the same as the branch where the thermistor 42 is located ( Figure 2The resistance values ​​of the upper and lower branches are the same, and no current flows through the fan 44 and the heating resistor 45, and the fan 44 and the heating resistor 45 do not work. When the ambient temperature is higher than the optimum temperature, the resistance values ​​of the branch where the variable resistor 43 is located and the branch where the thermistor 42 is located differ, and the current flows from the lower side to the upper side. At this time, due to the presence of the diode, the cooling branch is connected, and the heating branch is not connected. The fan 44 starts to work to cool the environment until the ambient temperature reaches the optimum temperature, and the cooling branch and the heating branch are not connected; when the ambient temperature is lower than the optimum temperature, the current flows from the upper side to the lower side. At this time, the cooling branch is not connected, and the heating branch is connected. The heating resistor 45 starts to work to heat the environment until the ambient temperature reaches the optimum temperature, and the heating branch and the cooling branch are not connected.

[0057] For high arch dams, structural joints must be set perpendicular to the dam axis from the foundation to the dam top during construction to reduce the temperature stress of the concrete, adapt to the uneven deformation of the foundation, and meet the requirements of concrete pouring capacity and temperature control. Under strong earthquakes, the transverse joints in the concrete arch dam will open, close, and move relative to each other along the joint interface, which will have a great impact on the stress size and distribution of the dam body.

[0058] At present, the treatment measures for the transverse joints of arch dams include adding beam-oriented steel bars, which are complex to construct and have poor effects. There are also methods such as configuring viscous dampers, but the effect of shock absorption and energy dissipation cannot be improved with the increase of the transverse joint opening.

[0059] Therefore, based on the above embodiments, the present invention also provides a high arch dam shock absorber, including the above-mentioned shape memory alloy damper, such as Figure 3 As shown:

[0060] When the dam body is subjected to earthquake action, the first reserved compartment 61 and the second reserved compartment 62 will undergo relative displacement as the transverse joint 5 opens and closes. Figure 3 At this time, the shape memory alloy damper 7 is stretched or compressed, and the shape memory alloy wire 733 inside it is stretched. As the displacement of the transverse joint 5 from the original position increases, the deformation of the shape memory alloy wire 733 also increases, and the shock absorption and energy dissipation effect of the shape memory alloy damper 7 is enhanced, which can greatly reduce the impact of the earthquake on the dam body.

[0061] The present invention uses shape memory alloy to make a shape memory alloy damper, so that no matter it is under tension or compression, the internal shape memory alloy wire will be elongated, thereby improving the utilization efficiency of the shape memory alloy wire; we apply it to the high arch dam structure to achieve earthquake resistance and vibration reduction. As the displacement increases, the effect of vibration reduction and energy dissipation will also increase, thereby improving the earthquake resistance of the structure. Shape memory alloy has good durability, good corrosion resistance, and a long service life, but when the external temperature fluctuates, it is easy to affect its vibration reduction performance. Therefore, we also add a temperature control adjustment unit to the shape memory alloy damper to adjust the temperature of the environment in which the shape memory alloy wire is located, so that the shape memory alloy wire can play the maximum vibration reduction effect.

[0062] Obviously, the above embodiments are merely examples for the purpose of clear explanation and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the present invention.

Claims

1. A shape memory alloy damper, characterized in that: include: The fixed body is provided with a first groove with one end closed and the other end open to fit the sliding body, the closed end of the fixed body is provided with a first lug, and two first sliding grooves are provided on both sides of the left and right sides of the first groove; The sliding body is placed in the first groove, a first portion of the sliding body close to the closed end of the fixed body is provided with a second groove, a second portion away from the closed end of the fixed body is provided with a second lug, and two second slide grooves with the same length as the first slide groove are provided on both sides of the left and right sides of the second groove; The first connecting rod and the second connecting rod connected by winding a shape memory alloy wire are placed laterally on the first slide groove and the second slide groove, so that the first slide groove and the second slide groove on the fixed body and the sliding body remain aligned in pairs, and the shape memory alloy wire remains stretched and unstressed.

2. The shape memory alloy damper according to claim 1, characterized in that: After the first sliding grooves and the second sliding grooves on the fixed body and the sliding body are kept aligned in pairs, the sliding body is at a certain distance from the closed end of the fixed body.

3. The shape memory alloy damper according to claim 2, characterized in that: The first chute includes a first left sub-chute and a first right sub-chute, and the second chute includes a second left sub-chute and a second right sub-chute.

4. The shape memory alloy damper according to claim 3, characterized in that: When the fixed body remains stationary and the second lug is under tension: The sliding body moves toward the side away from the closed end of the fixed body, the first connecting rod is constrained by the right limit piece on the first left sub-slot and remains stationary, the second connecting rod is constrained by the left limit piece on the second right sub-slot, and moves together with the sliding body in the direction away from the closed end of the fixed body, and the shape memory alloy wire is stretched.

5. The shape memory alloy damper according to claim 4, characterized in that: When the fixed body remains stationary, the shape memory alloy wire is stretched to generate a restoring force so that the second connecting rod is subjected to the tension of the shape memory alloy wire: The first connecting rod is constrained by the right limit piece on the first left sub-slide groove and remains stationary. The left limit piece on the second right sub-slide groove is acted upon by the thrust of the second connecting rod, driving the sliding body to move toward the closed end of the fixed body, and the shape memory alloy wire returns to its initial state.

6. The shape memory alloy damper according to claim 3, characterized in that: When the fixed body remains stationary and the second lug is pressed: The sliding body moves toward the side close to the closed end of the fixed body, and the first connecting rod is constrained by the right limit piece on the second left sub-slide groove. As the sliding body moves toward the direction close to the closed end of the fixed body, the shape memory alloy wire is stretched, and the second connecting rod is constrained by the left limit piece on the first right sub-slide groove and remains stationary.

7. The shape memory alloy damper according to claim 6, characterized in that: When the fixed body remains stationary, the shape memory alloy wire generates a restoring force after being compressed, so that the first connecting rod is subjected to the tension of the shape memory alloy wire: The second connecting rod is constrained by the left limit piece on the first right sub-slide groove and remains stationary. The right limit piece on the second left sub-slide groove is acted upon by the thrust of the first connecting rod, driving the sliding body to move in a direction away from the closed end of the fixed body, and the shape memory alloy wire returns to its initial state.

8. The shape memory alloy damper according to claim 1, characterized in that: It also includes a temperature adjustment unit, which includes: power supply; a thermistor connected in parallel with the power supply; a variable resistor connected in parallel with the power supply, wherein the resistance value of the variable resistor is set to the resistance value of the thermistor at the optimum temperature of the shape memory alloy; A cooling branch includes a fan connected in series with the cathode of the first diode; A heating branch circuit includes a heating resistor wire connected in series with the anode of the second diode; The temperature-lowering branch and the temperature-increasing branch are connected in parallel between the thermistor and the variable resistor.

9. The shape memory alloy damper according to claim 8, characterized in that: The working process of the temperature regulating unit includes: When the ambient temperature is the optimum temperature, the resistance of the branch where the variable resistor is located is the same as that of the branch where the thermistor is located, no current flows through the fan and the heating resistor, and the fan and the heating resistor do not work; When the ambient temperature is higher than the optimum temperature, the resistance values ​​of the branch where the variable resistor is located and the branch where the thermistor is located differ, the current is connected to the cooling branch, and the fan starts to work to cool the environment until the ambient temperature reaches the optimum temperature; When the ambient temperature is lower than the optimum temperature, there is a difference in the resistance value between the branch where the variable resistor is located and the branch where the thermistor is located. The current is connected to the heating branch, and the heating resistor starts to work to heat the environment until the ambient temperature reaches the optimum temperature.

10. A high arch dam shock absorber, comprising the shape memory alloy damper according to claims 1-9.

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