Experimental evaluation of load distribution in precast prestressed hollow core floors

Abstract Floors made of precast prestressed hollow core slabs can distribute applied point loads due to the presence of cast‐on site joints, tying systems, and torsional stiffness of individual units. While this phenomenon itself is well known, it has not been investigated enough experimentally. To further broaden the understanding of hollow core floor behavior under point loads, three full‐scale experiments were performed in which floors of different spans and cross sections were subjected to point loads. Gathered data such as displacements, forces and strains measured bi‐directionally by distributed fiber optic sensors allowed direct evaluation of reaction force, flexural bending moment and shear force distribution. Subsequent analysis of results showed that the units interconnected by cracked joints can effectively distribute loads between each other. Distribution factors depend on the span, load location on the transverse and longitudinal location, as well as the distance from the applied load. The extent to which load effect is distributed is different for support reactions, bending moments, and shear forces.