ABSTRACT

This paper presents a new hybrid passive control device, consisting of a viscoelastic and a friction damper connected in parallel, to mitigate the effects of wind and seismic events. The two components are synergized with the aid of a novel locking mechanism, which enables the action of one or both the components depending upon the device deformation. This provides an innovative two-phase energy dissipation capacity, and exploiting the individual strengths of the two dampers together. The response of a single degree of freedom (SDOF) hybrid damped system is represented in terms of a linear system using equivalent linearization technique, which includes all associated parameters such as the added stiffness, the added damping and the locking mechanism. In order to ascertain the influence of various parameters of the hybrid device, normalized force and normalized displacement are defined in terms of linear SDOF hybrid damped system and further used to obtain force reduction factor for multi degree freedom (MDOF) system with hybrid device. The proposed design methodology of controlling the structural response using the hybrid device is then applied on a six-story reinforced concrete (RC) building. The response of the conventional moment resisting frame (MRF) system and moment resisting frame system with hybrid device (MRHDF) are compared using the nonlinear time history analysis. The performance of the MRHDF system is found to be superior than the MRF system. The hybrid device can effectively reduce the dynamic response of the building, especially in terms of inter story drift, residual drift, base shear and floor acceleration. In addition the proposed design methodology is very simple as compared to the response modification factor approach. This configuration of hybrid device shows improved performance for meeting multiple objectives under wind/seismic events of real-life structures.

摘要

本文提出了一种新的混合被动控制装置，由并联的粘弹性和摩擦阻尼器组成，以减轻风和地震事件的影响。这两个组件在一种新型锁定机构的帮助下协同工作，该锁定机构使一个或两个组件的动作取决于设备的变形。这提供了创新的两相能量耗散能力，并同时利用了两个阻尼器的各自优势。单自由度 (SDOF) 混合阻尼系统的响应使用等效线性化技术以线性系统的形式表示，其中包括所有相关参数，例如附加刚度、附加阻尼和锁定机制。为了确定混合设备各种参数的影响，归一化力和归一化位移是根据线性单自由度混合阻尼系统定义的，并进一步用于获得具有混合装置的多自由度（MDOF）系统的力折减系数。然后将所提出的使用混合装置控制结构响应的设计方法应用于六层钢筋混凝土 (RC) 建筑物。使用非线性时程分析比较了传统抗弯框架（MRF）系统和具有混合装置的抗弯框架系统（MRHDF）的响应。发现 MRHDF 系统的性能优于 MRF 系统。混合装置可以有效降低建筑物的动力响应，特别是在层间漂移、残余漂移、基础剪力和楼层加速度方面。此外，与响应修正因子方法相比，所提出的设计方法非常简单。这种混合设备的配置显示了在现实结构的风/地震事件下满足多个目标的改进性能。