Experimental Investigations on Ferrocement Roof Slab System for Low Cost Housing

The work presents the results of an experimental investigation carried out to assess the strength of pre-cast roof slab system comprising of ferrocement slab panels resting over RC beams. In the ferrocement panels, the cement was replaced by 0 and 20 % fly ash. This roof slab system proves out to be a cost effective and structurally safe and viable alternative for low cost housing, much better than the conventional roofing system comprising of steel girder and brittle sand stone panels commonly used in regions where sand stone panels are easily available. The testing includes three sets of roof system comprising of 12 ferrocement panels placed on two pre-cast RC beams, and an enclosure of brick walls on four sides. A similar set of roof slab system comprising of 12 sand stone panels in place of ferrocement panels were also tested for comparison. The testing was continued till the cracks were pronounced. It was observed that load carrying capacity of RC beam and ferrocement panel system with same thickness is higher as compared to similar arrangement of RC beam and sand stone panels. The crack propagation phenomenon was also studied. The ferrocement roof slab system exhibited ductile failure whereas brittle failure was observed in case of sand stone roof slab system. Cost analysis reveals that two pre-cast systems of RC beams and ferrocement panels with and without fly ash are economical as compared to red sand stone panels or RC slab system. The theoretical calculations have also been carried out to establish the adequacy of the sections to sustain the flexural loading applied in the present investigation.