自复位记忆合金阻尼器的数值模拟及工程应用

发布时间：2018-03-29 23:03

本文选题：记忆合金　切入点：超弹性　出处：《华南理工大学》2013年博士论文

【摘要】：形状记忆合金（Shape Memory Alloy）的超弹性是指材料在外力作用下会发生马氏体相变，产生较大的变形，应力去除后会发生马氏体逆相变，并恢复到原来的形状。利用记忆合金的超弹性可以耗能，开发出了多种自复位记忆合金阻尼器，部分记忆合金阻尼器也在实际工程中得到了应用。利用自复位的记忆合金阻尼器进行耗能减震时，不需要外部能量的输入，结构没有残余侧移，值得重视。为推广记忆合金阻尼器的工程应用，本文利用记忆合金材料的Brinson本构模型，通过MATLAB编程进行阻尼器的力学性能模拟，并在此基础上通过时域积分进行SMA阻尼器减震效果分析与评价。本文具体工作如下： 1.介绍了对记忆合金的超弹特性，并对直径1mm的NiTi SMA丝进行了力学试验，研究了加载速率、应变幅值及循环次数等因素对SMA超弹特性的影响。同时，介绍了记忆合金的唯象本构模型的发展演变过程，并利用Brinson本构模型在MATLAB中编程得到材料的相变运动方程的数值解，从而描述SMA材料的应力-应变关系。实验与理论分析结果表明采用Brinson模型的数值模拟能很好的反映SMA材料的超弹性。 2.介绍了三种典型的自复位SMA阻尼器构造，通过将阻尼器元件分为回位组和耗能组，并在此基础上研究了阻尼器发生相对位移时各功能组元件的内力变化。针对利用预张拉的SMA丝组耗能、弹簧提供回位力的自复位SMA阻尼器，建立了力学平衡方程，，并在Brinson本构模型的基础上，根据阻尼器内部相对位移推算出耗能组反力，叠加弹簧反力，借助MATLAB编程从而计算出整个阻尼器的力-位移滞回曲线。 3.利用记忆合金本构模型，通过MATLAB编程，对布置自复位SMA阻尼器进行减震的三层钢框架结构进行了结构动力响应分析。具体分析过程如下：首先将结构模型简化为层间剪切模型，并提取出主结构的刚度矩阵、质量矩阵和阻尼矩阵；建立被动结构的动力方程，利用Wilson-θ法并考虑阻尼器提供的控制力，在MATLAB软件中编制了结构的动态仿真分析程序。选取El Centro(NS)波、Northridge(NS)波和Taft波作为地震激励，对结构分别进行了有控和无控的动力响应分析，对比了两种情况下结构的层间位移响应、楼层最大加速度与最大楼层剪力。 4.为评价自复位SMA阻尼器的振动控制效果，对自复位SMA阻尼器进行了Benchmark结构分析，具体为：针对高、中、低层三种Benchmark结构，在SAP2000中建立了有限元模型，分析了有控与无控结构的地震动响应，评价了自复位SMA阻尼器对不同结构的减震作用。另外，对采用自复位SMA阻尼器加强的某6层宿舍楼加固工程，分析了阻尼器布置方式对结构减震效果的影响。
[Abstract]:Shape memory alloy (Shape Memory Alloy) refers to the super elastic material will undergo a martensitic transformation under the external force, deformation, should reverse martensitic transformation will force after the removal, and return to its original shape. The memory alloy can super elastic energy, the development of a variety of self reset memory alloy the damper, part of memory alloy damper has been applied in practical engineering. By using the energy dissipation from memory alloy damper reset, without the need of external energy input structure, not worthy of attention shift, residual side.
For the engineering application of memory alloy damper, this paper use the Brinson memory alloy material constitutive model, simulate the mechanical properties of the damper through MATLAB programming, analysis and evaluation of SMA damper based on temporal integration and on the basis of the specific work is as follows:
The 1. introduces the super elastic characteristics of memory alloy, mechanical test and the diameter of 1mm NiTi SMA wire, studied the influencing factors of loading rate, strain amplitude and cycle times of SMA super bomb. At the same time, the memory alloy phenomenological constitutive model of the evolution of the development process, and the use of the numerical Brinson constitutive model in MATLAB programming solution of the equations of motion of phase change materials, so as to describe the stress-strain relationship of SMA materials. The experimental and theoretical analysis results show that the simulation can reflect the SMA material's super elastic numerical Brinson model was used.
The 2. introduces three typical self reset SMA damper structure, the damper element is divided into back group and energy group, and on the basis of the damper force variation functional components of the relative displacement. For the use of pre tensioned SMA wire group energy, self centering spring return force of SMA damper the established mechanics balance equation, and based on the constitutive model of Brinson damper, according to the internal relative displacement calculated energy group force superposition spring reaction force, using MATLAB programming to calculate the damper force displacement hysteresis curve.
3. of the memory alloy constitutive model, through MATLAB programming, the three storey steel frame structure layout self resetting of SMA dampers for structural dynamic response analysis. The specific analysis is as follows: first, the structural model is simplified as interlaminar shear model, and extract the main structure of the stiffness matrix, mass matrix and damping matrix the establishment of dynamic equation; passive structure, using Wilson- method and considering the control force with the damper, in MATLAB software for dynamic simulation analysis of the structure of program. Select El (NS) Centro (NS) wave, Northridge wave and Taft wave as seismic excitations on the structure were carried out with no power control and analysis the comparison of structural response control, two cases of inter layer displacement response, maximum acceleration and maximum floor shear.
4. for the evaluation of self vibration reduction and SMA damper control effect on self reset SMA dampers for Benchmark structure analysis, considering the high, low, three layer Benchmark structure in SAP2000 finite element model, analyzed the response control and no control structure of the seismic evaluation, self reset SMA damper on the damping effect of different structures. In addition, the reinforcement from a 6 storey dormitory building to strengthen the reduction of SMA damper, analyzes the influence of damper arrangement on the structural damping effect.

【学位授予单位】：华南理工大学
【学位级别】：博士
【学位授予年份】：2013
【分类号】：TU352.1

【参考文献】