A Framework for Evaluating Thermal–Structural Behaviour of Spherical Concrete Domes Subjected to Ventilation-Controlled Fire

Spherical concrete domes are commonly used in administrative buildings, silos, tanks, and subterranean structures. The main benefit of using concrete domes is utilizing both concrete durability and the high load capacity of a dome system that resists loads through meridian and ring stresses. The incident of an interior fire accompanied by superimposed loads requires specific considerations due to thermal deformations and material degradation resulting from the development of non-uniform temperature through the dome thickness. Moreover, dealing with ventilation-controlled fire, rather than standard fire, requires particular fuel load distribution and compartment ventilation considerations. This paper investigates the thermal behaviour assuming a ventilation-controlled steady-state temperature distribution within the dome space and transient temperature distribution through dome thickness while considering parameters related to ventilation factors and dome configuration. Outputs of the thermal analysis were fed into a structural model to estimate deformations and stresses. The effect of structural load ratio in conjunction with the ventilation factor during the fire incident was considered for a realistic study case.