Feasibility of Seismic Retrofit Using an Energy Dissipating Cladding System

在4号地震带，有许多旧的、现有的建筑不符合1991年统一建筑规范的横向强度、漂移控制和延性细节要求。一项使用假设建筑的初步研究表明，可以通过非侵入性改造方案提供额外的强度、刚度和能量耗散，该方案包括用结构（钢）面板和能量耗散包层与框架连接替换现有的包层。为了详细研究这个改造计划，我们将研究两座旧的现有建筑物。首先将进行初步设计，其中包括：(1)关于现有框架和包层系统对改造建筑系统的相对结构贡献的设计决策；(2)对包层系统进行了实用的包层与框架连接及其附件的设计，并制定了包层板的设计程序。该抗震改造方案的可行性将通过将改造的周长框架置于一系列具有峰值地面加速度范围、主要频率和持续时间的地面运动中进行分析评估。这项研究将从两个方面推动结构被动控制的发展：(1)通过确定包层结构特征和包层与框架连接可以有效和高效的条件，以及(2)为现有弱建筑或新设计的建筑制定合理的耗能包层系统设计指南提供基础。

In Seismic Zone 4, there are many older, existing buildings that do not meet the lateral strength, drift control, and ductile detailing requirements of the 1991 Uniform Building Code. A preliminary study using hypothetical buildings indicates the additional strength, stiffness, and energy dissipation can be provided by a non-invasive retrofit scheme involving the replacement of the existing cladding with structural (steel) panels and energy dissipating cladding-to-frame connections. To examine this retrofit scheme in detail, two older, existing buildings will be studied. A preliminary design will be done first, which includes: (1) design decisions regarding the relative structural contributions of the existing frames and the cladding system to the retrofit building system; and (2) for the cladding system, design of practical cladding-to-frame connections and their attachments, and development of a design procedure for the cladding panels. The feasibility of this seismic retrofit scheme will be assessed analytically by subjecting the retrofit perimeter frames to a set of ground motions with ranges of peak ground accelerations, predominant frequencies, and durations. The research will advance the state-of-the-art in passive control of structures in two ways: (1) by identifying conditions under which the structural characteristics of cladding and cladding-to-frame connections can be effective and efficient, and (2) by providing a foundation for the development of rational guidelines for the designs of energy dissipating cladding systems for either existing weak buildings or newly designed buildings.