Dhami, Sabita creator Pennung Warnitchai Chairperson Krishna, Chaitanya Examination Committee Anwar, Naveed Examination Committee Computer and Structures Inc.(CSI), USA Scholarship Donor AIT Scholarship Scholarship Donor text series technical report th Pathum Thani, Thailand Asian Institute of Technology 2025 continuing eng

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81 leaves : ill.+ 1 online resource This study presents a development of a numerical optimization framework for identifying the optimal column-jacketing strategy to enhance the seismic performance of a multi-story reinforced concrete structure.The work is focused on determining both the most effective locations of columns to be retrofitted with reinforced concrete (RC) jackets and the corresponding optimal jacket thicknesses using gradient-based numerical optimization technique. The case-study structure is a two-story building with an irregular arrangement of infilled walls in the ground floor, resulting in a soft-story condition.To improve computational efficiency, optimization is performed on two linear models with infill walls represented as equivalent struts using upper- and lower-bound elastic moduli,capturing both stiff and weak infill conditions.Three ground motions with short, moderate, and long predominant periods are considered. The framework begins with a stepwise optimization where multiple retrofit configurations are tested, followed by simultaneous optimization of column locations and jacket sizes using binary variables with a penalty function. A single retrofit scheme that satisfies constraints for all ground motions and both linear model variants is then selected.To evaluate the realism of linear-model-based optimization results, a nonlinear model is developed using the most effective solution and subjected to nonlinear time-history analysis.Comparing linear and nonlinear responses helps assess whether the linear-based optimum solution reflects true structural behavior.Overall, this study demonstrates a systematic and practical methodology for determining optimal column-jacketing configurations in multi-story buildings, contributing toward more reliable and faster seismic retrofit decision-making. A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering in Structural Engineering Thesis (M. Eng.) - Asian Institute of Technology, 2025 Earthquake resistant design Reinforced concrete construction Columns, Concrete Testing Asian Institute of Technology. http://203.159.5.9/ait-thesis/Viewer/viewer.php?id=B23425 http://203.159.5.9/ait-thesis/Viewer/viewer.php?id=B23425 260202 20260818090706.0