A Deformation Based Methodology for the Evaluation and Upgrading of Existing Structures

9319434 Krawinkler该项目关注的是发展基本概念和基本信息，这些概念和信息需要形成一种基于变形的方法，用于评估和加固现有结构。 该方法旨在（1）评估现有结构的预期抗震性能并确定基本加固需求，（2）促进有效加固方案的制定，并为加固方案组件所需的强度和变形能力提供目标值，（3）允许验证加固结构的抗震性能，并为加固方案要素的微调提供信息，以及（4）提供有关变形要求的信息，这些变形要求将控制加固方案中各元素的详细要求。 在变形基础评估/加固方面存在知识空白，反映了控制抗震性能的物理现象，本研究旨在填补大部分空白。 就以下三个专题进行研究：（1）单自由度和多自由度系统的抗震强度和位移要求的量化，（2）制定用于执行和评估“推倒”分析的程序和标准，该分析将作为评估/验证过程的一部分，（3）变形法概念的形式化，使其成为工程专业中一种可行的、有吸引力的工具。 这项研究的成功完成将使人们有可能实施一种方法来修复和加强地震脆弱的结构。 它代表了一个独特的机会，以推进实践的状态，并引入变形控制作为设计过程的一个公认的组成部分。 这是NSF倡议下的一个奖项， 结构抗震加固研究。" ***

9319434 Krawinkler This project is concerned with the development of basic concepts and fundamental information needed to formalize a deformation based methodology for the evaluation and strengthening of existing structures. This methodology is intended to (1) permit an assessment of the expected seismic performance of existing structures and the identification of basic strengthening needs, (2) facilitate the development of an effective strengthening scheme and provide target values for the required strength and deformation capacities of the components of the strengthening scheme, (3) permit a verification of the seismic performance of the strengthened structure and provide information for fine-tuning of the elements of the strengthening scheme, and (4) provide information on the deformation demands that will govern requirements for detailing of the elements of the strengthening scheme. There have been knowledge gaps in deformation base evaluation/strengthening which reflects the physical phenomena that control seismic performance and this research is intended to fill most of these gaps. Research is conducted on the following three topics: (1) Quantification of seismic strength and displacement demands for Single- Degree-of-Freedom and Multiple-Degree-Of-Freedom systems, (2) development of procedures and criteria for the execution and evaluation of a "push-over" analysis that is to be employed as part of the evaluation/verification process, and (3) formalization of the concepts of the deformation method to the extent that it can become a feasible and attractive tool for the engineering profession. A successful completion of this research will make it possible to implement an approach to repairing and strengthening of seismically vulnerable structures. It represents a unique opportunity to advance the state of the practice and introduce deformation control as an accepted part of the design process. This is an award under NSF-Initiative "Repair and Rehabilitation Research for Seismic Resistance of Structures." ***