Temperature effects on load transmission between slabs and shores

This paper analyses the influence of temperature changes on load transmission between floor slabs and shores during the in situ casting of concrete slabs by the shoring-clearing-striking method. Therefore several experimental studies were carried out which measured both the internal temperature evolution of the slabs and the loads on the shores. With the results of these studies, a Finite Element Model (FEM) of an experimental structure was then developed. In both the FEM and the experimental studies the same behaviour was observed regarding changes in temperature. When temperatures rose, the loads on shores decreased, accompanied by a reduction in slab deflection. When temperatures dropped, the loads on the shores increased, accompanied by an increased slab deflection. In the experimental study, for a temperature increment of ±1 °C the load per surface unit on shores varied between 0.13 kN/m2 and 0.34 kN/m2, which represents between 2% and 6% of the self-weight of the slabs. The main cause of these load variations appears to be the temperature gradient inside the floor slabs.