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Before discussing some basic Do‘s and Don‘ts of good concrete practice, it is useful to have a general definition of concrete. ("Concrete" as discussed here is taken to mean Portland cement concrete, as distinct from asphaltic or biluminous concrete, which is mostly used for road pavements, Portland cement concrete is also suitable for making roads, airport runways, and such the like).
Although the history of Portland Cement is comparatively short, the use of the structural binding agent dates back thousands of years. One of the earliest examples is that of the water tanks at Aden which were constructed 6000 B.C. and are still in use today. Analysis of the mortar used by the Egyptians in the construction of the “Pyramid of Cheops” in about 3600 B.C. show that they possessed a good practical knowledge of the subject at the time.
Almost any natural water that is drinkable and has no pronounced taste or odor can be used as mixing water for making concrete. Some water which may not be suitable for drinking may still be safe for mixing concrete.
After the mix has been designed, it must then be made; this involves the batching, mixing, transportation, handling on site and placing, compaction, finishing, and curing and protecting from mechanical damage; Sometimes the hardened concrete needs finishing again (such as grinding (e.g. terrazzo or granolithic floors) or the application of protective and/or decorative treatments to the hardened surface).
Much Portland cement is wasted, lost, is reduced in quality, or is made unusable, by careless or badly informed handling, transportation and storage. Though used all over the world for construction jobs from the largest to the smallest, and often taken for granted, Portland cement is in fact a high technology; quality assured manufactured product made to strict and carefully controlled international standards.
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