Proposed mix design method for producing sustainable self compacting heat cured recycled aggregate concrete and its microstructural investigation. (10th September 2019)

• Record Type: Journal Article
• Authors: Rajhans, Puja; Chand, Gaurav; Kisku, Nishikant; Panda, Sarat Kumar; Nayak, Sanket
• Is Part Of: Construction & building materials. Volume 218(2019)
• Page Start: 568
• Page End: 581
• Publication Date: 2019-09-10
• Subjects: Heat cured concrete -- Self compacting concrete -- Microstructure analysis -- Recycled aggregate concrete -- Equivalent mortar volume method; Building materials -- Periodicals; 624.18
• DOI: 10.1016/j.conbuildmat.2019.05.149
• Languages: English
• ISSNs: 0950-0618

Abstract

Graphical abstract: Highlights: Sustainable SCHCRAC prepared from C&D waste. Improvement of later stage strength of SCHCRAC by using silica fume and fly ash. SCHCRAC prepared by adopting Nan Su mix design method in conjunction with equivalent mortar volume (EMV) method. Improved properties of SCHCRAC by using modified two stage mixing approach ( TSMAsfc ). Quantitative microstructural investigation for justifying the presence of strength contributing elements. Abstract: The proposed mix design is based on concept of equivalent mortar volume (EMV) method in conjunction with Nan Su mix design method to develop sustainable self compacting heat cured recycled aggregate concrete (SCHCRAC). The residual mortar content which is adhered to the recycled aggregate is the integral part of total mortar requirement of the proposed design mix. Two stage mixing approaches are followed along with treatment of RCA for enhancing the properties of SCHCRAC. The properties are negatively influenced due to elevated temperature resulting formation of unhydrated cement clinker during heat curing process. To improve the properties and later stage strength, admixtures like fly ash, and silica fume are used. The microstructural investigation is done by using electron probe micro analyzer (EPMA) to justify the improved strength and it is observed that the two stage mixing approach (TSMA sfc ) results clear and stronger interfacial transition zone (ITZ). Quantitative analysis and elemental mapping are also carried out to know the presence of strength contributing elements.