A comparison of two methods for testing the resistance of fresh scc to segregation

Paper i proceeding, 2007

This paper presents experimental results from a comparison study of two methods, the sieve stability test and the J-ring test, for testing the resistance of fresh self-compacting concrete (SCC) to segregation. The sieve stability test is based on the measurement of the sieved portion of the sample passing through a 5 mm sieve, while the J-ring test is based on the difference between two measurements of the blocking step. Different mixes of fresh SCC with natural, blended natural and crushed, and crushed aggregates were tested in parallel using both the test methods. Concrete were cast in plastic pipes with 2 m height using some of representative mixes with crushed aggregates. Specimens from different heights were taken for testing compressive strength and chloride migration coefficient. The results show that there is a fairly good correlation in the measurement results from the two methods for the SCC with natural aggregates, but not for that with crushed aggregates. The relationships between the fresh and hardened properties of SCC as well as some discrepancies between the two methods in the test results are discussed.