◆A low sand rate or a low content of fine particles in the sand will result in low water retention of concrete. A high mud content in the sand will easily cause slurry settlement, that is, “grabbing the bottom.”
◆The total amount of cementitious materials is small, and the slurry volume is less than 300L/m3;
◆The stone gradation is poor, or the stones are of a single particle size;
◆Large water consumption makes the viscosity of the concrete mixture low;
◆The amount of admixture is too large, or the admixture has low viscosity and poor water retention;
◆Use slag or slag Cement itself has poor water retention and is prone to bleeding and segregation.
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