Durability Properties of Self Compacting Concrete with Recycled Aggregate and Silica Fume by Mohd Ishfaq
Concrete is widely used construction materials. As we know, it is a mixture of coarse aggre-gates, fine aggregates, binded together by cement with addition of water. Concrete which is highly flow able and can fill the form work under its own weight, consolidates without any mechanical vibration is known as selfcompacting concrete, thus cause self-compaction. Such concrete accelerate the time of placement, reduce the labour work needed for consolidation, finishing and reduces environmental pollution. The so called first generation SCC is used mainly for repair applications and in restricted areas where it is not possible to reach easily, comprising sections that present limited access to vibrate. It has been used in applications justifying the higher material and quality control cost when considering the simplified placement and handling requirements of the concrete. Silica fume is one of the best improvements of the rheological as well as the mechanical and good chemical properties. It also improves the dura-bility of the concrete. In this present study, tests on replacement of coarse aggregates with recycled aggregates and replacement of silica fumes with cement had been done. Tests were conducted for fresh prop-erties of self compacting concrete, i.e. filling ability, passing ability, segregation resistance, so as for obtaining fresh properties according to SCC EFNARC 2002 concrete mix. The different durability properties such as chloride penetration depth, abrasion resistance, were determined on various concrete mixes. Their compressive strength was also found. Replacement by silica fume decreases chloride penetration depth, depth of wear. Concrete mix having 50% recycled aggregate and 10% silica fume replacement had comparable durability in term of the chloride depth, abrasion resistance.