J-Ring (AIM 334 J)

This test method provides a procedure to determine the passing ability of self-consolidating concrete mixtures. The difference between the slump flow and J-Ring flow is an indication of the passing ability of the concrete. The test method is applicable for laboratory use in comparing the passing ability of different concrete mixture. It is also applicable in the field as a quality control test. It can also be used to investigate the resistance of SCC to segregation by comparing test results from two different portions of sample. The J-Ring test measures three parameters: flow spread, flow time and blocking step. The J-Ring flow spread indicates the restricted deformability of SCC due to blocking effect of reinforcement bars and the flow time indicates the rate of deformation within a defined flow distance. The blocking step quantifies the effect of blocking.