“Computational Civil Engineering - "Intersections" International Journal

“Computational Civil Engineering 2005”, International Symposium 2251. INTRODUCTIONThe definition of structural identification is the development of an analyticalconceptualization of a structure, or region thereof (including supports andcontinuity), and quantifying, testing, improving, and validating the resultinganalytical model by correlating responses simulated by the model with thosemeasured from the structure [1]. The structural identification requires integratedanalytical and experimental components of research or applications.The identification methodology proposed for large structures such aresuperstructures of bridges, have 10 steps [1]:1. Study the structure to be identified, including its support mechanism, byexamining existing information about the structure, e.g. construction drawings,record drawings, inspection records, and visiting the site.2. Based on synthesis of the data from step 1, develop a referenceanalytical model of the structure. The model should include all potentially criticalmechanisms of flexibility/stiffness, inertia, and if possible energy dissipation.3. Establish reasonable upper and lower bounds of the values of the modalparameters in the model.4. Conduct parametric sensitivity studies to find the mechanisms offlexibility, inertia and damping that govern response. Determine which particularresponses are most affected by these mechanisms.5. Reduce the reference model to include only those parameters, termed the“critical” parameters that model the governing mechanisms.6. Conduct experiments on the structure to reliably generate and measurethe responses most sensitive to the governing mechanisms. Use the upper andlower bounds of responses established in step 4 to guide selection of the type andmanner of use of equipment.7. Apply an algorithm to the measured data to quantify modal parametersand then those dealing with inertia [m], flexibility [k], and, if possible, energydissipation [c].8. Alter values of the parameters of the reduced-reference analytical modeluntil a best fit between model and experimentally generated flexibilities is reached.9. Validate the reliability of the process.10. Return to step 1 or some other intermediate step as indicated by thevalidation procedure.Based on this proposed identification methodology, the objectives of thispaper are to integrated analytical research of step 4 (to find the mechanisms of