Develepment of a new test method to evaluate dynamic stability of self-consolidating concrete

Abstract

Self-consolidating concrete (SCC) is a new generation of concrete with high performance. It is able to flow under its own weight and fills the formwork without any external vibration. Stability is the most important plastic and crucial property for successful application of SCC and it refers to segregation of constituent in fresh state. Dynamic stability is the segregation resistance of SCC during transportation and placement. Evaluation of dynamic stability is one of the most investigated topics of SCC. Many different test methods have been proposed to evaluate the dynamic stability of SCC. No single and widely accepted method exists for the evaluation of the dynamic stability of SCC. In this thesis a new apparatus for testing the dynamic stability of SCC was developed. The effect of different mix design parameters such as water-to-cement ratio w/c, slump flow diameter, coarse aggregate-to-total aggregate ratio (CA/TA), and maximum size of aggregate (Dmax) were evaluated on the dynamic stability of SCC. Several fresh concrete tests were carried out on the SCC mixtures: slump flow, T500 time, Visual stability index (VSI), V-funnel, L-box, static sieve segregation (GTM), rheometer, and new proposed method (DSST). Several correlations were established between the test results. It was found that the new proposed test is a suitable method to evaluate the dynamic stability of SCC. Limits were proposed for a dynamically stable SCC.