Concrete And Its Effects On The World After Water

1141 Words5 Pages
INTRODUCTION

1.1 Background to the Study

Concrete is the second most utilized substance in the world after water and is the most widely used construction material with an annual global production of about 10 billion tonnes. It is preferred in most structures because of its unique properties such as durability and high compressive strength. It is however relatively weak in tension, its tensile strength being about 10-15 % of its compressive strength requiring that it be reinforced with materials such as steel rods, glass or plastic fibers in order to improve its ductility. It is also prone to slight shrinkage during the drying process and may lead to cracking especially in normal strength concretes. (R. I. Gilbert, 2001). As defined by the Portland Cement Association, the durability of concrete is its ability to counteract abrasion, weathering action and chemical attack, and still maintain its desired engineering properties. The proportioning and interactions between concrete ingredients, placement and curing practices as well as the service environment determine this ultimate durability and life. The ideal situation therefore in any construction project is to choose the correct concrete type which will be more durable based on the project requirements.
Traditional vibrated concrete is most commonly used but it has limitations such as difficulty to place in areas of congested reinforcement, difficulty to place in irregular complex formwork and lack of compacting assurance
Get Access