Some Observations on Concrete with Phosphogypsum and Glass Fibres

Increasing infrastructural needs have been creating huge stress on available natural resources leading to environmental deterioration. In the developing nation like India, concrete is commonly adopted material in major infrastructure projects. Environmental burdens associated with manufacture and processing of raw material for concrete are enormous. Major impact associated with concrete production is carbondioxide gas emission during cement manufacturing and depletion of natural resources for aggregate production. These environmental issues have paved the way for adopting eco- friendly materials and techniques in concrete production. Industrial by-products such as fly-ash, blast furnace slag, silica fume etc. are being successfully employed as cement replacement for sustainable concrete production. The present research has examined the potential of phosphogypsum the by product of fertilizer industry as a partial replacement of cement (5%, 10%, 15% and 20%). Compatibility of phosphogypsum with cement has been initially studied and adopted for production of M20 concrete. Performance of the processed concrete was analyzed through workability and mechanical properties. Results obtained prove that phosphogypsum has the potential for adaptation as retarder in concrete production but optimum replacement was found to be only upto 10%. For enhancing the properties of the concrete, the study has been extended with partial replacement of glass fiber (0.5%, 1%, 1.5% and 2%) for M20 concrete with phosphogypsum content (5% and 10%) of cement replacement. Obtained results have suggested the suitability of utilizing these materials (with 1.5% glass fibre and 10% phosphogypsum) for M20 concrete.