ABSTRACT

Self compacting concrete (SCC) is a very fluid concrete that compacts under its own weight. This concrete is able to fill all formwork corners by passing trough reinforcement bars. It should present enough cohesion to prevent segregation of gravel or bleeding. Thus the concrete can be easily placed and it is suitable to be used in situations which were previously impossible to execute using traditional concrete.

The original idea for the creation of this concrete was suggested by Okamura (1986) to overcome problems related to durability of reinforced concrete structures as a result of the decrease of the quality of the specialized workers for the execution of the compaction processes. The aim was to create a product that could guarantee the compaction without having the human factor as a variable capable of affecting the quality of the final product.

The study and use of self-compacting concrete have been increasing since its initial proposal. Some advantages of its use rely on the faster placement and lower demand of workers in the cast process, the possibility to produce elements of difficult forms or highly reinforced, and the amount of energy spared, associated with the improvement of the work conditions due to the reduction of the noise in compaction.

Therefore the "Departamento de Ingeniería de la Construcción y PIC" from "Universidad Politécnica de Valencia" has started to develop a research program on self compacting concrete. A literature revision on this subject has been done, focusing mainly in the dosage methods and the tests used to characterize this kind of concrete in fresh and hardened state.

Aiming the gain in efficiency when designing self-compacting concrete, the use of reduced size models was proposed to fit the dosages and characterize these concretes.

The influence of the admixtures in the rheological behaviour of the cement pastes used on the production of self-compacting concrete were studied and characterized.

The adherence of self-compacting concrete on active reinforcement was studied by determining the transmission and anchoring length.  The results were compared with the ones from traditional concretes of reference.

The robustness of the self-compacting concrete dosages was studied, varying the materials weights. Statistical software was used in the analysis of the results obtained from laboratory tests.

At last, a self compacting concrete was designed and applied in the construction of the columns of the North Round cross road in Valencia.