Experimental studies on CSRDM specimen to validate the use of Ritz vectors for the response evaluation of structures subjected to multi-support excitation

The control and safety rod drive mechanism is a classic example of a multiply supported and differentially excited structure as it receives varying inputs at each of its supports as they are connected at different parts of a building. The responses of such systems are conventionally computed using pseudo-static method in which the dynamic component is evaluated by time history analysis, response spectrum method or modal analysis. In the present work the dynamic components are evaluated by using Ritz vectors and are compared with the conventional methods namely time history analysis and modal analysis. The usage of Ritz vectors as an alternative for conventional modal vectors has been validated through an experiment conducted on a control and safety rod drive mechanism (CSRDM) subjected to differential input motion. The validation of the code developed for this purpose is carried out for a bridge structure.