Assessment of durability of Self compacting concrete by use of Steel and Polypropylene fibers in addition with recycled coarse aggregates.

ABSTRACT: The durability of concrete is one of the prominent influencing factor for better serviceability of any concrete and over the past few decades numerous researches has also been done in order to understand the behaviour of Self compacting concrete(SCC) with addition of fibres in combination with recycled aggregates. With development in concrete engineering, waste generated due to demolition of concrete structures also is a concern. Sustainable development is presently a major issue all over the world. The use of recycled concrete aggregate (RCA) in concrete as partial and full replacements of natural coarse aggregate (NCA) is growing interest in the construction industry, as it reduces the demand for virgin aggregate. Hence recycled coarse aggregates (RCA) can be used as replacement to NCA in order to reduce the environmental pollution and waste of resources in construction process. In this paper an attempt has been made to compare the effect of durability properties on SCC by addition of steel fibre (SF) and polypropylene fibres (PF) in various volume fractions from 0.05% to 0.15% with an interval of 0.05% and fixed percentage of RCA replaced with natural aggregates. Present work focuses mainly to evaluate the effect of low percentage fibres and fixed percentage of recycled aggregates on durability of SCC. In the existing study the mix design for M40 grade SCC is made using Nan Su method by replacing 25% of natural aggregates with recycled aggregates. Number of durability tests such as Acid test, Chloride test, Sulphate test and Water absorption test were conducted to understand the influence of fibres on durability of SCC. Thus the present study highlights to substantiate the effective usage of fibres to enhance durability properties of SCC.