Fire Safety Science Digital Archive

A series of analytical studies is presented on the behavior of an unprotected plane composite steel-concrete frame under fire scenarios which occur across single storeys of the structure. The main purpose is to assess the effectiveness of using various types of sub-assembly in predicting the structural behavior in fire. The studies are based on modeling a full-scale experimental multi-storey frame in which some fire testing is to take place shortly, and in part originate from a program of analyses in which the authors have participated whose aim has been to determine the test parameters required. For the basic modeling studies the frames and sub frames are assumed to be rigidly connected, but the effect of the semi-rigidity of real connections is also investigated. The analyses are all performed using a program NARK!, whose most recent development has been the capability to take into account strain reversal whenever it happens. This allows an assessment of the residual effects on the frame members after a local fire has been extinguished and the frame has returned to ambient temperature.