By the end of the Nineteenth century, the British rulers had imported 'Cement' to India and commenced discouraging the method of using freshly ground lime for masonry construction that was in vogue in India since ages. If properly used, the cement construction could be made fairly waterproof. The construction could last as well appreciably long and gave hardly any trouble of maintenance, similar to slaked lime construction to the users. The Portland cement age was dawning in India! Local industrialists as well went ahead and established cement factories here. Being a factory manufactured material it was touted to be always of uniform (and good) quality. By the end of Second World War, the fresh lime grinding as a process of preparing masonry material had been fully relegated into an historical construction activity!
In late fifties when we civil engineering students of Government College of Engineering Pune, were taught this subject of cement concrete, it was emphasized that Concrete structures like bridges will last for over 60 years whereas residential accommodation can give satisfactory service for over 100 years! The cement concrete was quite strong and durable, even better than "finely and freshly ground lime" under use then. Even RCC was also being used by engineers with success. We students were awestruck with the new found material and the technique of its use. The mix design for 1:2:4 (volume batch concrete) RCC, we used to need 15 to16 one CWT (112 Lbs) bags of cement to make 100 cft of finished concrete. Sometime the cement could go up to even 17 bags. The mix design was introduced with a hollow box (3' x 3' x 3') packed fully with coarse aggregate additionally packed with fine aggregate and in turn this interfiled with finer powder of cement. The body of concrete being aggregate the cement was only the binding agent as we could understand. Any more small voids in this box were supposed to be filled with the expanding cement gel after it reacts with the mixing water in the concrete. The resulting concrete was supposed to be even waterproof.
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