August 25, 2018: HCC team engaged in the construction of Fast Reactor Fuel Cycle Facility (FRFCF) at Kalpakkam, in Tamil Nadu, achieved a significant milestone by successfully completing continuous concrete pour of a massive 8000 cum of temperature controlled concrete for construction of a raft. It took 130 hours of nonstop pouring of concrete, at placement temperature of 230C, across an area equivalent to a football field. This incredible feat was achieved 19 hours ahead of schedule and is by far the largest pour in the history of the Department of Atomic Energy.
The high-performance concrete of N45 grade with 10% fly ash was used for raft concreting. The sequential method of pouring was adopted with over 500 layers of concrete being poured to avoid cold joints. The team had planned for the concrete pouring rate of 53.4 Cum/hr, but with meticulous planning and implementation, they achieved an average rate of 58 cum/hr of concrete with the highest pour of 102 cum/hr.
Starting at 14:00 hrs on August 20, 2018, the project team worked in shifts for 5 days till 24:00 hrs on August 25, 2018. The pouring was done 23 m below the ground level under varied weather conditions and amidst monsoon rains. About 95 workmen were deployed per shift to carry out this mammoth task.
For a continuous feed of 8000 Cum of concrete, the team required around 16000 MT of aggregate, 2900 MT of cement, 750 MT of ice and 720 MT of fly ash. Due to limited storage space, managing these inventories was a big challenge. Around 30% of the construction material was brought to the site after the concrete pouring began.
The storage capacity of the cement at the site was 1100 MT. Hence, while 950 MT cement was brought to the site, nearly 35 bulker trucks carrying 850 MT cement were kept on hold during the pouring process. To supply 750 MT of ice, 15 temporary ice containers were brought to the site having a total capacity of 310 MT, besides in built facility to store 160 MT ice and around 270 MT ice was produced from our ice plant during the pour. Similarly, around 400 MT of the fly ash was brought to the site during the pouring process. Additional equipment was kept on standby to mitigate breakdown. The entire supply chain management was handled with meticulous planning and precise execution. Kudos to the FRFCF team for this outstanding achievement.
Chief Executive Officer, HCC E&C