Mortar’s rheological property and workability investigation based on morphology impact factor for graded sand particles

Abstract

The morphology of sand particles strongly influences mortar rheology properties. A characterizing method for the morphology indicator of graded sand particles was proposed by morphology testing and analyzing. Then, taking sand volume fraction as the weight of the morphology indicator of the graded sand particles, the morphology impact factor was put forward to characterize the comprehensive effects of morphology and quantity of graded sand particles on the mortar performance. The effects of morphology impact factor on mortar rheology properties, workability and strength were explored by rotational rheometer, slump flow, anti-segregation and strength testing. The results show that the proposed morphology impact factor is capable of characterizing morphology effects of graded sand particles, well correlated with yield shear stress and slump flow of the mortar, and the slump flow can be predicted in terms of the yield shear stress of the fresh mortar; when the morphology impact factor is between 0.86 and 1.08, the fresh mortar possesses good fluidity and anti-segregation performance. This research, based on rheology, contributes a new way to the mortar and concrete design manner.