Materials Engineering Essay Example | Topics and Well Written Essays - 2500 words

Materials Engineering - Essay Example Many times, efforts would go in vain resulting into honeycombed elements upon removal of the formwork. In conventional concreting process, not only is there a chance of segregation and honeycombing in the concrete structural element, but also, chances that concrete would not even approach certain corners are quite fair causing steel to be exposed to open air and facilitating rusting and hence an altogether loss of strength of the structural member. This together with other difficulties in the preparation of conventional concrete and the exaggerated length of time and effort consumed in vibrating it called for a need to have such a model of concrete that would not require vibration to uniformly reach every corner in the element. Also, vibration was a tedious process and required effort of a large crew that would add a lot to the total cost of concreting. In addition to that, vibrated concrete leads to differential compaction and hence, varying durability along the length of the member . In response to these problems, after years of research and experimentation, engineers came up with such a model of concrete that did not require any vibration and was intrinsically self compacting in nature. Today, use of self compacting concrete is widely employed in structures and elements of dense and complicated reinforcement design. â€Å"Self-compacting concrete was first developed in 1988 to achieve durable concrete structures.† (Okamura and Ouchi, 2003). Because of the manifold enhancement in its performance, self compacting concrete (SCC) is also referred to as high performance concrete (HPC). HPC can be defined as, â€Å"Concrete that meets special performance and uniformity requirements that may not always be obtained using conventional ingredients, normal mixing procedures and typical curing practices.† (American Concrete Institute, 1997). The requirements that ACI refers to include but are not limited to ease of