輪椅使用者地震安全之振動台實驗與數值模擬研究

Shaking Table Experiment and Numerical Simulation Research on Earthquake Safety of Wheelchair Users

由過往的研究得知，輪椅使用者在地震時可能會面臨到的輪椅振動行為包含(傾斜角度由小到大)： Walking(走步)，Rocking(搖擺)，以及最危險的行為Overturning(翻覆)；其中翻覆還可分成側向翻覆以及向後翻覆。而受到不同的激振加速度振幅、頻率(可對應到各建築物樓高自振頻率)，則會觸發不同的輪椅振動行為發生，其中激振加速度振幅愈大、頻率愈低(高樓層建築物)愈容易造成輪椅的翻覆。本研究透過實驗以及建立數值模擬的方式發現，在同樣的加速度振幅作用下，當激振頻率低於輪椅翻覆的最高頻率時，輪椅亦會翻覆。因此，輪椅的翻覆頻率為一段範圍區間而非一特定值。當加速度振幅增加時，輪椅翻覆的頻率範圍也會提升。因此，對應到不同的加速度振幅，會有不同的輪椅翻覆頻率範圍。最後，由本研究的振動台實驗結果得知，以外部束制去固定輪椅後方的兩個把手，最能夠避免輪椅向後與左右傾倒。

 

Based on previous research, it has been found that wheelchair users may experience different wheelchair vibration behaviors during earthquakes, ranging from walking, rocking, to the most dangerous behavior—overturning, which can occur in sideways or backward directions. Corresponding to different acceleration amplitudes and excitation frequencies related to the natural frequencies of different building heights, different wheelchair vibration behaviors can be triggered. Among them, higher excitation accelerations and lower frequencies typically associated with taller buildings are more likely to result in wheelchair overturning. This study, through experiments and numerical simulations, has discovered that under the same acceleration amplitude, when the excitation frequency is lower than the highest overturning frequency of the wheelchair, the wheelchair can still overturn. Therefore, the overturning frequency of the wheelchair is within a range of values rather than a specific value. As the acceleration amplitude increases, the highest overturning frequency of the wheelchair also increases, and the low-frequency range expands accordingly. Consequently, different acceleration amplitudes correspond to different ranges of wheelchair overturning frequencies. Finally, the shaking table experimental results of this study indicate that fixing both handrails of the wheelchair with external restraints can effectively prevent the wheelchair from overturning in both backward and sideways directions.