Is BubbleDeck a truly more efficient solution to cast-in-situ slabs, when viewed in light of the local construction industry?

Abstract

BubbleDeck is a slab technology which has recently started being used in the local construction industry, whereby concrete in the middle of the flat slab is eliminated to reduce the dead weight of the slab. This slab system claims to provide substantial cost savings from a structural material point of view, due to the lower concrete requirement, and significant time savings over the more traditional concrete slab systems. This dissertation attempts to perform a comparison between traditional flat slab and BubbleDeck construction, from a structural, cost control and construction time point of view. The structural analysis involved examining several parameters to assess the performance of both a flat slab and a Bubble Deck reinforced concrete slab of the same dimensions and subjected to the same load and loading patterns, to obtain the volume of concrete and weight of steel reinforcement required to satisfy the limit states defined by EC2. Once the quantities of structural material required by both structural systems was determined, a costing exercise was carried out, comparing the cost of constructing a traditional flat slab with that of constructing an equivalent slab using BubbleDeck, based on construction rates commonly found in the local construction industry. The difference in construction time required was determined and converted into an opportunity cost, to obtain a like-with-like comparison between the two slab systems. A total of 6 slabs with different dimensions was examined, each of which was then analysed at 5 different potential rental rates to investigate the difference in opportunity cost for each rental rate. The results obtained from this research show that, for slabs with higher spans and higher rental rates, BubbleDeck is the more efficient solution.