Prediction of response of reinforced concrete frames exposed to fire

Balaji, Aneesha;Muhamed Luquman, K.;Nagarajanb, Praveen;Pillai, T.M. Madhavan

  • Received : 2015.08.16
  • Accepted : 2015.12.23
  • Published : 2016.01.25


The objective of this work is to study the restraining effect in fire resistance of framed structures and to evaluate the global response of reinforced concrete frames when exposed to fire based on advanced finite element method. To study the response a single portal frame is analyzed. The effect of floor slab on this frame is studied by modeling a beam-column-slab assembly. The evolution of temperature distribution, internal stresses and deformations of the frame subjected to ISO 834 standard fire curve for both the frames are studied. The thermal and structural responses are evaluated and a comparison of results of individual members and entire structure is done. From the study it can be seen that restraining forces has significant influence on both stresses and deflection and overall response of the structure when compared to individual structural member. Among the various structural elements, columns are the critical members in fire and failure of column causes the failure of entire structure. The fire rating of various structural elements of the frame is determined by various failure criteria and is compared with IS456 2000 tabulated fire rating.


reinforced concrete;fire safety;fire resistance;thermal analysis;thermo-structural analysis


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