Yield stress of Chengdu clay slurry

Abstract

The yield stress of mud is the key to the starting analysis of debris flow. Taking the clay in Longquan District of Chengdu as the experimental object, slurries with different solid volume concentrations were prepared. Using the blade rotor system of MCR301 rheometer, the continuous increasing shear rheological test of mud is carried out, and the dynamic change process of shear stress with the increase of shear rate is recorded. According to the results, the following conclusions are drawn: Chengdu clay mud is a non-Newtonian fluid with yield stress. When the solid volume concentration exceeds 35%, the shear rate is less than 1s-1, and the shear stress increases rapidly with the increase in shear rate. When shear rate is higher than 1s-1, the shear stress decreases with the increase in shear rate, and finally tends to be stable. There is a maximum shear stress near 1s-1. When the solid volume concentration is less than 35%, the shear rate is less than 0.1s-1, and the shear stress increases with increase in shear rate. When the shear rate is higher than 0.1s-1, the shear stress changes little with the increase in shear rate. An exponential relationship between mud (dynamic and static) yield stress and solid volume concentration can be seen.