论文标题:一种新型形状记忆合金超弹性阻尼器的理论与试验研究
Theoretic and Experimental Study of a New Type of Shape Memory Alloy Damper
论文作者 肖尔田
论文导师 韩玉林,论文学位 硕士,论文专业 工程力学
论文单位 东南大学,点击次数 106,论文页数 56页File Size1236k
2004-03-01论文网 http://www.lw23.com/lunwen_497822252/ 形状记忆合金; 结构控制 ;智能材料 ; 阻尼器 ;动力性能 ;恢复力模型 ; 地震
Shape memory alloy ; structural control; smart material ; damper ; earthquake dynamical property ; restoring force model ; history analysis
结构耗能减振技术是一种结构控制技术,它是通过在结构的适当位置安装耗能减振装置,利用这些装置的耗能来减小结构在强震和大风作用下的振动响应。形状记忆合金(Shape Memory Alloy,简称 SMA) 具有形状记忆效应、超弹性效应和高阻尼特性,利用超弹性效应制成的形状记忆合金超弹性阻尼器就是一种性能优良的耗能减振装置,它可以有效的控制结构的动力响应,在理论上和实用上都是很有价值的。本文在综述了国内外耗能减振技术的研究成果及工程应用状况后,设计了一种新型形状记忆合金超弹性阻尼器,讨论了这种新型阻尼器在工程上的一些应用形式,然后针对这种新型形状记忆合金超弹性阻尼器进行了理论和试验研究,最后进行了装有该种阻尼器的框架结构的地震动有限元分析。本文研究的主要内容和成果如下:1、基于形状记忆合金的超弹性特点,研制了一种新型形状记忆合金拉压、扭转及转动耗能阻尼器,这种阻尼器具有同时消耗拉压、扭转和转动三种振动能量的能力。2、基于这种新型形状记忆合金阻尼器的形状特点,探讨了它在建筑结构和桥梁结构上的多种应用型式及其受力特点。3、对该种新型形状记忆合金阻尼器进行了力学分析,推导了拉压、扭转及转动作用下阻尼力与位移公式,得出了耗能大小与各种影响参数之间的关系。4、进行了该种新型阻尼器动态力学性能试验,对影响新型形状记忆合金阻尼器工作性能的各种影响因素进行了研究。试验和研究表明,该种阻尼器在拉压、扭转及转动时具有较好的耗能能力,其滞回曲线与理论分析较一致。同时也验证了理论分析方法的正确性。5、比较了装有阻尼器和未安装阻尼器时框架在地震波作用下的振动衰减过程,数值模拟计算结果表明,该种形状记忆合金阻尼器可以有效的控制模型结构的动力响应,是一种性能良好的耗能减振装置。
Structural vibration energy dissipation is a kind of structural control technology, which employs energy-dissipation devices installed in proper locations of the structure to dissipate part of structural vibration energy under earthquake and wind so as to reduce the structural vibration response. Shape memory alloy (SMA) is an ideal material to dissipate vibration energy because of its properties of shape memory effect (SME), super elasticity effect and damping effect. So the shape memory alloy damper, which is based on these properties, is a good kind of energy-dissipation device. It can reduce the seismic and wind-vibration response of the engineering structures effectively. So the studies on the shape memory alloy damper are valuable in theory and practice. The current situations of researches and applications of shape memory alloy damper are briefly reviewed in this thesis firstly. Then a new type of damper device based on shape memory alloy (SMA) wires is developed for structural control implementation. Based on this new type damper, some new engineering applications in construction buildings and long-span bridges with this damper are proposed. Then the theoretic and experimental study of this new type of damper technology for structural vibration energy-dissipation is performed to verify the vibration energy dissipation ability of the new type of SMA damper. Finally based on the experimental results, finite element method is adopted to simulate the earthquake response of the frame model, controlled uncontrolled by SMA damper. The main contents and results are as follows.Based on the properties of the SMA, a new type of damper device based on shape memory alloy (SMA) wires is developed for structural control implementation. This kind of SMA damper can supply tension damping, compression damping, torsion damping and bending damping at the same time.Based on this new type damper, some new engineering applications in construction buildings and long-span bridges with this damper are proposed. It can be used in many kinds of structures and installed easily and have several advantages that other dampers don’t have.The theoretic study on such damper is performed, including the research on fundamental damping principle of the damper and mechanics damping analysis of such developed reduced-scale damper. The various affecting factors to the working performance of SMA damper are discussed. The formula of the output damping force and displacement is gotten when the damper is tensed or compressed, rotated and bent. The dynamical experiment of such reduced-scale damper is performed to verify the damping analysis results and the vibration energy dissipation ability of the new type of SMA damper. It is found that the experimental results are in good agreement with the theoretic values. From the experimental restoring force curve, the damping coefficient and stiffness of damper are calculated. Based on these parameters of the damper, finite element method is adopted to simulate the earthquake response of the frame model, controlled and uncontrolled by SMA dampers. The numerical results illustrate that the earthquake response displacement of the frame model is reduced greatly and its vibration decay rate is increased effectively after the developed SMA dampers are fixed in it. Such type of SMA damper is a good device to dissipate energy and to reduce the vibration of the structures.
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