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Content

Introduction………………………………………………………….1
Composition of concrete…………………………………………….1
First users of concrete……………………………………………….1
Portland Cement……………………………………………….2
Reinforcement………………………………………………….2
Composition of Portland Cement……………………………2
Hydration of Portland Cement………………………………3
Water and concrete……………………………………………3
Stenght of concrete……………………………………………4
Properties of concrete………………………………………..7



This project is about concrete and its properties.

There is written about concrete composition, who was the first users of concrete. Reading this project you will take much information about how to use concrete and where it is beneficial.
Concrete differs from other construction materials in that it can be made from an infinite combination of suitable materials and that its final properties are depended on the treatment after it arrives at the job site. The efficiency of the consolidation and the effectiveness of curing procedures are critical for attaining the full potential of a concrete mixture. While concrete is noted for its durability, it is susceptible to a range of environmental degradation factors, which can limit its service life. There has always been a need for test methods to measure the in-place properties of concrete for quality assurance and for evaluation of existing conditions. Ideally, these methods should be nondestructive so that they do not impair the function of the structure and permit re-testing at the same location to evaluate changes in properties with time.
Concrete is a compound material made from sand, gravel and cement. The cement is a mixture of various minerals which when mixed with water, hydrate and rapidly become hard binding the sand and gravel into a solid mass. The oldest known surviving concrete is to be found in the former Yugoslavia and was thought to have been laid in 5,600 BC using red lime as the cement.
The first major concrete users were the Egyptians in around 2,500 BC and the Romans from 300 BC The Romans found that by mixing a pink sand-like material which they obtained from Pozzuoli with their normal lime-based concretes they obtained a far stronger material. The pink sand turned out to be fine volcanic ash and they had inadvertently produced the first