局部肘节消能装置的减振机制分析及其优化控制

传统的肘节式位移放大机构可以增大阻尼器变形从而提高结构减振效率，但其需占据较大空间，且相关的基于小变形假设的位移放大系数理论公式不能反映放大系数时变特性，难以实现几何构造优化。为此，提出一种以黏滞阻尼器为阻尼元件的局部肘节消能装置，其具有占用空间小、布置灵活等特点。基于几何关系推导局部位移放大系数解析解，并对其进行参数分析。分析结果表明：局部凸肘节消能装置的位移放大能力随下连杆与水平面夹角增大而增强，而局部凹肘节消能装置则与之相反；局部凸肘节消能装置的最优下连杆长度与装置高度之比位于［0.7，1.3］区间内，局部凹肘节消能装置的该比值约为0.7。根据改进D值法提出适用于框架结构的局部肘节消能装置层间位移放大系数计算方法。以消能装置在外部激励下最大侧移为基础，给出了针对层间位移放大系数的优化步骤，并通过算例分析验证局部肘节消能装置的可行性和几何优化方法的有效性。采用所提优化方法进行局部肘节消能装置设计，可有效增强其位移放大能力和振动控制效果。

Optimization control and analysis on vibration control mechanism of local toggle energy dissipation device

The structural vibration control efficiency of traditional toggle-brace-damper systems may be improved by increasing the deformation of the damper. However, it needs to occupy a large space. In addition, the related theoretical formula based on the small deformation assumption cannot reflect the time-varying characteristics of the amplification factor, which makes it difficult to realize the geometric optimization of the toggle-brace-damper system. Against this background, a local toggle energy dissipation device equipped with viscous dampers was proposed in this paper. Its space occupation is small, and its arrangement is flexible. Based on the geometric relationship, the analytical solution of the local displacement amplification factor was derived. The parametric analysis was carried out based on the analytical solution. It can be concluded from the analysis that the displacement amplification capacity of the local convex toggle energy dissipation device increases with the angle between the lower toggle brace and the horizontal plane. While the displacement amplification capacity of the local concave toggle energy dissipation device decreases with the angle between the lower toggle brace and the horizontal plane. For the local convex toggle energy dissipation device, the optimal value of the ratio of the span-to-height lies in the range between 0.7 and 1.3. For the local concave toggle energy dissipation device, this optimal value is about 0.7. Subsequently, the calculation method of the inter-story drift amplification factor of the local toggle energy dissipation device was proposed based on the improved D-value method. The optimization steps for the inter-story drift amplification factor were given based on the possible maximum lateral drift of the local toggle energy dissipation device at external excitations. A case study was carried out to verify the feasibility of the local toggle energy dissipation device and the effectiveness of the optimization method. The results indicate that the displacement amplification capacity and the vibration control effect of the local toggle energy dissipation device can be obviously improved by the optimization method proposed in this paper.