New approach to assess build-up of cement-based suspensions

The structural build-up of cement suspensions at rest is a complex phenomenon affected by both physical and chemical structurations. Better understanding of this phenomenon relies on the efficiency of measurement approach. Dynamic rheometry was used to investigate the evolution of both storage modulus and phase angle of cement and inert calcium carbonate suspensions. Two independent build-up indices were proposed to identify the rest time needed to build a percolated elastic network and its rigidification rate with time. The structural build-up of various cement suspensions was evaluated using the proposed indices. These indices were then compared to the well-known thixotropic index (A(thix)). It was found that combining the percolation time and the rigidification rate can provide deeper insight into the structuration process of cement suspensions. Furthermore, these indices were found to be well-correlated to the decay in lateral pressure of cement suspensions. (C) 2016 Elsevier Ltd. All rights reserved.