Shear Wave Velocity and Its Anisotropy of Polymer Modified High-Volume Class-F Fly Ash–Kaolinite Mixtures

Abstract

AbstractThis study investigated the effects of polymers on the small-strain stiffness behavior of high volume Class-F fly ash–kaolinite mixtures. The shear wave velocity (Vs) and its anisotropy of organically modified fly ash–kaolinite mixtures were evaluated using a self-developed floating wall type consolidometer bender element (BE) testing system. Both synthetic polymers [polyethylene oxide (PEO)] and biopolymers (xanthan gum and chitosan) were used to modify the stiffness of fly ash–kaolinite mixtures. Shear waves generated and received by bender elements were measured to quantify the small-strain stiffness of the organically modified fly ash–kaolinite mixtures in three orthogonal directions, i.e., vh, hv, and hh. The results suggested that (1) as the fly ash content increased, Vs increased, while the Vs anisotropy, in terms of shear wave velocity ratio Vs−hh/Vs−vh, decreased; (2) a threshold fly ash content concept, which corresponds to the onset of continuous contact chains between fly ash particles...