Sensitivity Analysis of Dynamic Systems Subjected to Seismic Loads

Keywords: Dynamic systems.  Seismic loads.  Sensitivity analysis.  MATLAB implementation.  DIANA implementation.  Pipes.  Critical facilities.  Hospitals.  Computer software.

Abstract: This research provides analytical and numerical methods directed to the development of optimal strategies for improving the seismic performance of hospitals and other critical facilities.  The report investigates a measure of sensitivity termed the sensitivity factor, which is defined as the derivative of the response with respect to a parameter of the input or of the system.  This factor can be used to identify the critical parameters, as well as in applications such as calibration and optimization of system parameters.  A large part of the report is devoted to implementation of the direct differentiation method to calculate the sensitivity factors in computer software programs that can be used for the practical research, analysis, and design of real systems.  The computer programs used are MATLAB and DIANA.  The report also presents an example illustrating the application of the sensitivity factors in the analysis of the primary structural system and secondary nonstructural piping system of a hospital in Buffalo, New York.  This example demonstrates the use of the sensitivity factors in practical design and retrofit for systems of realistic size and complexity.