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

9319434 Krawinkler该项目关注的是基本概念和基本信息的发展，这些概念和基本信息需要形式化一种基于变形的方法，用于评估和加强现有结构。这种方法的目的是：(1)允许对现有结构的预期抗震性能进行评估，并确定基本的加固需求；(2)促进有效加固方案的制定，并为加固方案组成部分所需的强度和变形能力提供目标值。(3)允许对加固结构的抗震性能进行验证，并为加固方案要素的微调提供信息；(4)提供关于变形需求的信息，这些信息将指导加固方案要素的详细要求。在反映控制地震性能的物理现象的变形基评价/加固方面存在知识空白，本研究旨在填补这些空白。研究主要围绕以下三个主题展开：(1)量化单自由度和多自由度系统的地震强度和位移需求；(2)制定执行和评估“推倒”分析的程序和标准，该分析将被用作评估/验证过程的一部分；(3)形式化变形方法的概念，使其成为工程专业的可行和有吸引力的工具。这项研究的成功完成将使一种修复和加强易受地震影响的结构的方法成为可能。它代表了一个独特的机会来推进实践的状态，并引入变形控制作为设计过程的一个可接受的部分。这是美国国家科学基金会发起的“结构抗震修复和修复研究”下的一个奖项。＊＊＊

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." ***