Nonlinear response of uniformly loaded axially restrained beams under thermal (fire) loads.

摘要

The nonlinear response of axially restrained beams under thermal loads is analyzed using the method of geometric nonlinear analysis. Numerical solutions are shown for both pre and post buckling response of beams.;The analysis has been done for three different types of beams as given by AISC. These beams are referred from Table C-A-8.1 of AISC Manual (2010). The types of support conditions of the beams are hinged-hinged, fixed-hinged and fixed-fixed. All the beams were subjected to two levels of uniformly distributed loads with respect to their yield capacity along the length of the beam. For each of the beam support conditions, two slenderness ratios 50 and 100 were analyzed.;Some of the important conclusions drawn in this study are: • The temperature amplification factors seem to be significantly smaller than the load amplifications given by AISC. • Two lengths of beams were studied in this research in which the amplification factor for the smaller length beam were found to be slightly larger than amplification factors for the longer beam due to the same temperature increase. • Two different load conditions were used in this thesis, one being a half of yield moment and the other is one-tenth of the yield moment. The amplification factors were higher for the lower loading (ie. one-tenth yield moment) as compared the higher loading (ie. one-half of yield moment).