Fire resistance of hollow-core slabs supported on non-fire
protected Deltabeams
The goal of the four fire tests was to document the ability of Peikko Deltabeam without fire insulation to support hollow-core slabs during a fire situation. The result from the test showed that load transfer in the interface between a hollow-core slab and a non-fire insulated Deltabeam was fulfilled. The capacity of load transfer from a typical hollow-core slab and a typical Deltabeam during fire was at least – depending on the fire duration – 35% (REI60+), 29% (REI120+) or 19% (REI180) of the characteristic shear capacity of the slab in a cold design situation. The “+” means that the standard fire included the standard cooling phase.
Test panel
The test panels for the fire test consisted of a main Deltabeam with a span width of 3,915 mm.The span width of the slabs was 2,350 mm between the main beam and the two edge beams as shown in Fig. 1. The cross sections of the Deltabeams and the hollow-core slabs are shown in Figs. 2, 3, and 4.
The design and documentation of the bearing capacity of the Deltabeam was carried out by Peikko. The degree of utilization of the main Deltabeam and the two edge beams was practically equal in order to obtain unique deflections during the fire tests. The steel in the beams was S355J2+N in...