Workability and heat of hydration of self-compacting concrete incorporating agro-industrial waste

Abstract

This paper presents an experimental study on the workability and the heat of hydration in Self-compacting concrete (SCC) incorporating agro-industrial waste and blended aggregates.The control mixture contained only Ordinary Portland Cement (OPC) as the binder while the remaining mixtures incorporated binary and ternary cementitious blends of OPC, palm oil fuel ash (POFA) and fly ash. The replacement of waste was from 10% to 40% by mass of the total cementitious material of the concrete for workability test and limited to 30% and 40% replacement for the heat of evaluation test. Workability i.e. passing ability, filling ability and segregation resistance was determined and semi-adiabatic temperature rise during the initial stage of hydration was measured by thermocouples. It was observed that fly ash mixes required the least amount of super-plasticiser (SP) to obtain a workable SCC, however, POFA mixes had the reverse effect. The ternary use of POFA and fly ash had better workability properties than the POFA mixes and performed the best in terms of segregation resistance.The ternary mixes also had the lowest amount of heat dissipation with peak temperatures occurring earlier than the fly ash mixes. The experimental studies indicate that ternary blend SCC with POFA and fly ash has significant potential when considering a sustainable M A N U S C R I P T A C C E P T E D ACCEPTED MANUSCRIPT 3 construction material hence also providing a cleaner production solution for the palm oil industry.

Strength and microstructural characteristics of palm oil fuel ash and fly ash as binary and ternary blends in Self-Compacting concrete

“…The benefits of incorporating FA vary on its type, proportion used, fineness, grain composition and shape, and ignition loss (Siddique and Khan 2011). As seen in the previous work by the author, Nagaratnam et al, (2016), the FA reduces the water demand of SCC and produces a liquefied consistency. Hence, an improvement was found in the passing and filling ability yet an adverse reaction was observed with regard to the segregation of the mixes.…”

“…The core issue with this application is the hygroscopic nature of POFA that causes an increase in water demand in SCC, which is needed for a similar workability as FA (Nagaratnam et al, 2016). On the other hand, POFA improves the segregation resistance of the SCC.…”

Durability and mechanical properties of self-compacting concrete incorporating palm oil fuel ash

“…In addition, in terms of environmental considerations, incorporation of the cementitious supplementary material results in saving energy and resources by substantially reducing greenhouse gas emission which is due to obviation of limestone calcination, fuel combustion in the kiln, manufacturing and transportation processes associated with production of M A N U S C R I P T A C C E P T E D ACCEPTED MANUSCRIPT 3 Palm oil fuel ash (POFA) is produced by the palm oil industry as a result of the burning of empty fruit bunch (EFB), fiber and oil palm shell (OPS) as fuel to generate electricity at temperatures of about 800-1000 o C and the waste, collected as ash, becomes POFA (Nagaratnam et al, 2015). Malaysia produced about 3 million tons of POFA in 2007 while 100000 tons of POFA is being produced annually in Thailand, and this production rate is likely to increase due to increased plantation of palm oil trees (Chindaprasirt et al, 2007;Johari et al, 2012a;Ranjbar et al, 2014b;Tangchirapat et al, 2007).…”

Green Concrete: By-Products Utilization and Advanced Approaches

“…One drawback that can be found with POFA is the reduction of workability in fresh concrete mixtures [133,134]. Therefore, superplasticizers are needed with the addition of POFA [131,135,136].…”