Experimental Testing and Numerical Modelling of Heat Transfer Through a Composite Sandwich Flooring System with Penetrations Exposed to Fire

The designing of structures is an intricate process during which various aspects should be considered, one being fire resistance. Conventional materials such as concrete help structures withstand the effects of a fire. A composite sandwich flooring system, referred to in this paper, is completely void of concrete and has limited inherent fire resistance that is provided. For a flooring system like this, heat transfer will occur more rapidly. Fire-resistant boards are used to protect the system, but the fire rating of these boards is compromised by service holes—which is the focus of this paper. Experiments were conducted to examine the rate of heat flow through a sandwich ceiling system consisting of a Calcium Silicate (CaSi) board on the exposed face, a Voidcon steel sheet in the middle, and a Fibre Cement Board (FCB) on the unexposed face. Various holes, to simulate light and service penetrations, were made in the ceiling system. The experimental results made provision for a 30-minute rating for all the tested samples, with the shortest test taking place over approximately 40 minutes, but this is significantly less than the 60-minute original resistance. The experimental results were compared with simulated results generated using ABAQUS. This paper presents a summary of the comparison between the experimental and simulated results, highlighting important considerations and behaviour.