An Experimental Study on the Rheological Properties of Laponite RD as a Transparent Soil

Abstract
The shear rheological properties of Laponite RD as a transparent soil have been investigated by a thixotropic test, dynamic strain sweep, dynamic frequency sweep, and a creep test. The thixotropic test revealed the thixotropic curve of Laponite RD that consisted of deformation, flow, and destruction regions. The apparent viscosity in the flow region matched well with the result calculated from the Herschel-Buckley model. Dynamic tests showed that the elastic properties of Laponite RD were promoted with the increase in concentration. When the strain was less than 10 %, it exhibited linear viscoelasticity with slight frequency dependence. Under constant external force, the Burgers model was used to characterize Laponite RD; thereby, the parameters of the creep model were obtained. Our results shed light on the understanding of the rheological properties of Laponite RD to extend its application as transparent soil in geotechnical engineering.