A new-age self-compacting, self-levelling concrete, Agilia - recommended by Nuvoco Vistas Corp (formerly Lafarge India Limited) - was used for constructing a state-of-the-art Oncology Radiation Chamber in Kiran Multi Specialty Hospital in Surat; making it the first-of-its-kind in Gujarat.
The scope of work involved construction of three bunkers of 256 sq m (2,754 sq ft) as per the Atomic Energy Regulatory Board (AERB) regulations. These require the density of concrete to be uniform throughout the structure, with minimum density being more than 2,400 kg/m3. It bears pointing out that AERB has non-negotiable and stringent guidelines, and does not permit commissioning of a facility unless those specifications are met.
Nuvoco's Construction Development and Innovation Centre (CDIC) team provided method statement for placement of concrete; evaluation report of performance of different mix-designs to fulfil the requirements of the job-site, and designing of proper shuttering for better performance of Agilia. With proper planning and execution, the team was able to complete the project and hand it over to the hospital team an entire month before schedule, thereby saving considerable costs. Nuvoco supplied 800 m3 of M30 Agilia with temperature control for this project.
Agilia is an ideal solution for structures with complex configurations or requirements. In this case, Agilia was used to achieve the desired density and to minimise voids within the concrete by more than 50 per cent as compared to normal concrete. One of the challenges faced during execution was that the structure was approximately 5 m below ground level. The laying and changing of the pipeline was critical to maintain a cohesive mix and to avoid pump choking. This was done by maintaining the maximum core temperature below 70¦C and a temperature gradient less than 20¦C by using higher Pozzolana materials in concrete.
Frederic Guimbal, Chief of RMX and Aggregates, said,'We were sure Agilia would be the answer since it offers better packing density and cohesiveness over regular concrete. Due to its self-consolidating nature, Agilia drastically reduces voids, thereby minimising the risk of radiation leakage.'