竹质框架模型动力试验的数值仿真研究

Study on Numerical Simulation for Dynamic Test of Bamboo-based Frame Structure Model

为了确保进一步研究设置耗能减振装置结构仿真分析的可靠性,首先借助于小型振动台,对无耗能减振装置的三层竹质框架模型进行了振动台试验,测试了实际模型的自振频率和不同测点加速度时程数据。其次利用有限元计算软件MIDAS/Gen建立竹质框架数值模型,分别通过调整数值模型竹材的弹性模量和阻尼比,使数值模型与实际模型的自振频率和加速度时程数据最大值相等的方式进行数值仿真研究。仿真研究得到的数值模型与实际模型的加速度时程曲线吻合良好,证实了结构的阻尼比取值随地震波振动强度的增大而增大的结论。

In order to ensure reliability of structural simulation analysis for further study of the structure with energy dissipation devices,small-size shaking table was used for carrying out the model shaking table test of a three-floor bamboo-based frame structure without energy dissipation devices.The natural vibration frequency of the real model and acceleration time-history date of different measure points were tested.Then the numerical model was built in finite element software MIDAS/Gen.Value of elastic-modulus of bamboo in MIDAS/Gen was adjusted to equalize the natural vibration frequency of real model and numerical model; value of damping ratio in MIDAS/Gen was also adjusted to equalize the maximal value of acceleration time-history date of two models.The result of numerical simulation shows that acceleration-time curve of two models are in good agreement.The results also substantiates that structural damping ratio increases with an increase of the vibrating intensity of seismic wave.