Segregation Characterisics of Fresh concrete

点击翻译按钮获取中文摘要

Dragging Ball Viscometer test, slump test, funnel test and T-shaped tube test were carried out on con- cretes of which mix propotions were changed widely, and these tests were simulated by DEM (distinct element method). The results can be summarized as follows.(1) Relations between Bingham constants and mix proportions were determined based on dragging ball viscometer tests, and relations between Bingham constants and DEM parameters were determined by DEM analysis. Equations to determine DEM parameters based on mix proportions were proposed using these results.(2) It was concluded from the results of DEM analysis on slump test, funnel test and T-shaped tube test using the DEM parameters determined as above that behavior of fresh concrete can be simulated almost satisfactorily, provided Bingham constans in the analysis are near to those in the experiments.(3) However, it was also found that applicable range of equations relating Bingham constants to DEM parameters is relatively narrow due to the deviations of analysis and that behaviors of fresh concrete can not be simulated beyond this range. Further studies are needed to set up more precise equations.(4) It was made clear qualitatively by DEM analysis where and how segregation of coarse aggregate and resulting blockade occur and propagete in funnel test and T-shaped tube test.