Workability and sag control in mortars containing mineral rheological additives
Mortars require sag or slip control agents to avoid potential application problems. Workability is a property commonly referred to in the mortar industry. This paper outlines a new approach, the Tolsa method, to compare different additives in relation to this workability concept using a Viskomat NT rheometer for mortars.
1. Introduction
It is well-documented that fresh mortars mostly behave as Bingham fluids [2]. Accordingly, a majority of studies have essentially focused on investigating two rheological parameters: yield stress and plastic viscosity, and the change of the latter as a function of the shear rate. A simple representation of these parameters in flow curves can give a good idea of the properties of fresh mortars based on their rheological behavior. Nowadays, this type of rheological analysis is much easier to carry out due to the use of rheometers, whilst always taking into account that cement is a...