Natural fibre-reinforced polymer composites are seen as a possible substitute to synthetic fibre-based composites to face the environmental issues related to non-biodegradable nature of synthetic fibres. Due to their high specific strength and modulus, natural fibre-reinforced polymer composites are receiving widespread attention. In the present research initiative, natural fibre-reinforced thermoplastic composites have been developed with microwave curing technique. Two types of natural fibres namely sisal and grewia optiva, and two types of thermoplastic polymers (polypropylene and ethylene vinyl acetate) were used for fabrication of composites. Microwave wattage and exposure time were optimized for successful curing of thermoplastic composites. Results of tensile, flexural and impact strength of developed composites showed improvement in the properties as compared to neat polymers. The results suggest that microwave energy provides a feasible, environmental friendly option for curing of natural fibre-based thermoplastic composites.

The disposal of solid waste in open environment is a serious alarming concern that needs immediate attention from the researchers. The hazardous solid agro-industrial wastes which include: wheat straw ash, rice husk ash, corn cob ash and sugarcane bagasse ash (SCBA), having pozzolanic properties, have a versatile use in concrete. The solid pozzolana enhances the various concrete properties by the reaction of silicates with calcium hydroxide in the presence of water, which in result generate a saturated zone of calcium silicate hydrate (CSH) gel. This C-S-H gel reduces the amount of calcium hydroxide C(OH)2 during the hydration process of cement. Very limited research works have been done on concrete by partially replacing cement with SCBA. This research work was focused on evaluating the properties of concrete by partially replacing cement with SCBA at 0, 5, 10, and 15 percentages. Compressive strength, Strength activity index, and water absorption of all mixes were examined. And it was observed that all SCBA mixes showed an increase in compressive strength and at 10% replacement the strength activity index was at a peak of 115.67%, but all the SCBA mixes showed a strength activity index greater than 75% which satisfied the standard specification. The water absorption test for all SCBA mixes showed a slight increase in water absorption.

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Silica fume is an industrial by-product that can be used as a partial replacement of cement to enhance the strength related properties of roller compacting concrete. In past, industrial wastes were used to dump on earth, river, and sea that creates a hazardous environment for aquatic life as well as for humans. Nowadays, the use of industrial by-products as cement replacement is popular in the construction industry because it protects the environment from hazards. In this research, the effect of silica fume as partial replacement of sulphate resisting cement is investigated on the compressive strength of roller compacting concrete. Total four types of mix proportions were casted using concert mix ratio as 1:2:4 to investigate the compressive strength of roller compacting concrete at 7 and 28 days of curing age. The sulphate resisting cement was partially replaced with silica fume by 0%, 5%, 10%, and 15% by weight of cement. The zero slump was maintained in all mixes. It was observed that the mix proportions containing 5% and 15% silica fume replacement showed maximum and minimum compressive strength of roller compacting concrete respectively.