Punching Shear Behavior of Concrete Flat Slabs in Elevated Temperature and Fire

Two-way concrete flat slabs provide a number of benefits for office buildings, parking garages and apartments - for example, reduced form work, prompt erection, minimal increase in story heights, and flexibility of partitions. Concrete flat slabs could be vulnerable to punching shear failure in the event of a fire. There are a limited number of studies available on concrete flat slabs for punching shear failure in fire. In the present study, a set of six reinforced concrete slabs are tested in ambient and elevated temperature to investigate their strength characteristics in punching shear failure. A model to estimate the punching shear capacity is developed and correlated with the available experimental data. Using the above model, a detailed parametric study is carried out to study the effects of various factors affecting the punching shear behavior. It is also shown that the existing code provisions for punching shear cannot predict slab behavior under fire exposure in some cases.