Post Fire Dynamic Analysis of Steel Buildings Subject to Wind Loadings in South of Iraq

Abstract

Post-fire analysis of a six-story square steel building under the action of dynamic wind forces in the south of Iraq is presented. The nonlinear time-history analysis using direct integration method is accomplished by SAP 2000 V16 program while geometric nonlinear parameters are included. The post fire deformations values and their configurations along building are based on available literature that related to post fire deformations of steel buildings at 550^oCwith reducing of yield stress and modulus of elasticity) by 10% due to fire. In the present study, two post fire scenarios are considered, with wind speed of 42 m/s, according to Iraqi meteorological and IQS.301 standards. The aim of this study is to investigate the post-fire dynamic analysis of a multi-story steel moment-resisting building subjected to dynamic along-wind loads. Variations of base shear, base moment, drift ratio, and displacement are considered for discussion and comparison. Its concluded that the presence of deformation in building after fire and the reduction in yield stress and modulus of elasticity increased the base shear, base moment and drift ratio as average by about 12.5, 20& 64%respectively under the effect wind load. The fire deformations may be critical and the structural decision for the building safety should be done via structural analysis of the building taking into consideration different parameters related to post fire effects.