Reinforced Cement Concrete floor slab

 INTRODUCTION

A roof/intermediate floor is constructed to span between supports such as walls and columns. It is structurally designed to safely carry the ‘dead load’ of its own weight (including finishing layers above it) and any additional ‘live load’ imposed by human activity. The most common technique for constructing the roof/ floor in India is by casting a Reinforced Cement Concrete (RCC) slab. Reinforced Cement Concrete, as it is practiced today, has been in use since 1867. RCC slab is a monolithic element which consists of cement concrete which encases within itself a matrix of steel rods called ‘reinforcement’. It uses the unique property of concrete to quickly harden into a rigid mass after being laid in different forms and thicknesses. However, concrete, which is most efficient in resisting compressive loads, is very poor in resisting tension which develops when it bends. So, the performance of concrete is further enhanced by placing reinforcement rods in the concrete which allows the concrete to resist the bending which would result in a thin RCC slab spanning between two supports.  RCC scan either be cast-in-situ by pouring concrete on shuttering or it can be pre-cast where smaller sized slab components are first made and then transported and installed at the site to create the floor/roof. The biggest advantage of RCC slab is that the basic raw materials needed for its construction – cement, sand, steel and aggregates – and skilled masons for casting the slab are easily available everywhere. However, because RCC has become such a commonly practiced technology, basic quality control guidelines for a good quality and durable RCC slab are often ignored in practice, specially in rural areas, where it has not been traditionally practiced.