If you travel to Normandy in France, you'll still see the remains of the German bunkers used in the failed attempt to hold the beaches during D-Day. On another note, the bunker deep inside the Cheyenne Mountains is designed to withstand a nuclear blast equivalent to 1,875 Hiroshima bombs. What makes both structures tough enough to withstand the test of time?
Part of the secret lies in the quality of the concrete used. This simple mixture of cement, water, rocks, sand, and air creates a composite material known to be not only long-lasting but tough. Provided that the right mix is achieved, buildings can benefit from the strength and endurance of this material, which has been around since Roman times.
To avoid miscalculating concrete mixes, contractors normally set up concrete batch plants on site. These massive mixing systems provide cement trucks with the right concrete mix for various applications. As there's no universally accepted recipe, the task of achieving the right mix still falls upon the operator. The system will, however, take into account calculations like the water/cement ratio.
The mixture is then loaded onto a cement truck at the distribution station. Thereafter, the truck will keep the mix fluid until it reaches the site, where it will be casted onto the framework.