It is said that structural elements made with self-compacting concrete show denser and more uniform microstructure, reflecting in smaller variations of mechanical properties and better durability. This research describes the results of an investigation carried out to evaluate the variation of compressive strength of SCC in precast beams and columns. Two different SCC were used, with 650 mm and 800 mm slump flow, and compared with vibrated ordinary concrete with slump of 10±1cm. All concretes had compressive strengths in the order of 60 MPa. Preparation, transport and pouring were rigorously controlled. The uniformity of the concretes in the precast elements was analyzed along the whole length of the full-size elements (beams and columns) by the determination of concrete core compressive strengths. The segregation of the coarse aggregates was also determined by image analyses of sawed concrete surfaces. The results indicated that in columns SCC compressive strengths varied less than ordinary vibrated concrete properties. The maximum difference in the average compressive strength in columns were 13,3% for the 650 mm slump flow SCC; 12,3% for the 800 mm, and 22,5% for the ordinary vibrated concrete. On the other hand, the variability of the concretes in beams was smaller for ordinary concrete than SCC.
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