Precast, prestressed concrete hollow-core slabs have
gained wide popularity in recent years due to their
numerous advantages over other forms of construction.
These advantages include aesthetics, speed of construction,
efficient use of space, and flexibility. Structural
fire safety is a primary consideration in buildings; thus
building codes specify fire-resistance rating requirements
for hollow-core slabs. The current method of evaluating
fire resistance of precast, prestressed concrete hollow-core
slabs is mainly through standard fire tests. The current prescriptive
provisions are developed based on standard fire
tests on precast, prestressed concrete hollow-core slabs,
and fire resistance is derived in terms of concrete cover
thickness and slab thickness. Because these prescriptive
provisions do not consider fire scenarios as encountered
in buildings, they may not reflect realistic fire resistance
of hollow-core slabs. Further, these prescriptive methods
account for a narrow range of parameters.
Generally, concrete exhibits higher fire-resistance properties
than steel does.1,2 Therefore, under fire conditions the
temperature rise in prestressing strands often governs the
fire resistance of hollow-core slabs. In hollow-core slabs,
the presence of void cores affects the thermal inertia of
slabs, influencing temperature transmission through the
slab thickness. The transmission of heat from the fire
source to the slab is through radiation and convection,