ABSTRACT
The Nathpa Jhakri Power Project being constructed by Nathpa Jhakri Power Corporation Limited, is a run of river scheme located in the middle reaches of the river Satluj utilizing 488 m gross head available between Nathpa and Jhakri for power generation. A proven system to control the consistency, ensure good workability, low pumping pressure, adequate slump retention and low rebound was made mandatory. The contractors were asked to provide the technical documentation showing compatibility between superplasticiser and accelerators they proposed to use. The technical specification ensured the use of only environment friendly silicate based accelerators which could ensure rebound lower than 10 per cent overall and have lower fibre rebound by means of having thixotropic consistency when the shotcrete hit the substrate. The use of steel fibre was restricted to only those with over 1000 map tensile strength and manufactured under approved quality assurance system.
