摘要
Two-stage(pre-placed aggregate)concrete(TSC)consists of coarse aggregate,which is first deposited into the formwork,and grout,which is later pumped into the formwork from the bottom up to bind the stone together into a monolith.During the course of this study the formation of grout for two stage concrete was investigated using readily available 5 mm sand mixed in a slow speed paddle mixer.Silica fume and a superplasticizer were used in the mix to see if the necessary stability and fluidity could be achieved without the use of a specialized plant,essentially to see if TSC could be produced on a small scale using native Irish aggregates.A much higher degree of sedimentation was recorded during testing than was expected.As a result,the use of 5 mm sand and a slow speed mixer in combination were found to be not conducive to the successful production of TSC grout,without further research and testing.
