Modeling Shear Failure in Precast Prestressed Concrete Hollowcore Slabs under Fire Conditions

Abstract

Prestressed concrete hollowcore slabs are susceptible to shear failure under fire conditions. However, current approaches do not consider shear limit state in evaluating failure of hollowcore slabs under fire conditions. This paper presents an approach for modeling the fire response of PC hollowcore slabs by taking into consideration shear limit state. A three dimensional finite element model is developed for evaluating failure of fire exposed prestressed concrete (PC) hollowcore slabs under various limiting states, including shear. This nonlinear finite element model, developed in ANSYS, utilizes a transient thermo-structural analysis to trace the response of typical hollowcore slabs under fire condition. The validity of the model is established by comparing temperatures, deflections and failure modes from the numerical model with data obtained from fire tests. This model can be utilized to study the effect of critical parameters on shear response of PC hollowcore slabs