Experimental investigation of frost heave in clayey sands: Effects of density and thermal conditions

This study experimentally investigates the effects of soil density and temperature boundary conditions on frost heave behaviour and ice lens formation in saturated specimens composed of a binary sand - kaolin mixture. Controlled freeze-thaw tests have been conducted to simulate field frost conditions, using a cold plate to impose various subzero temperatures on one side of the sample while maintaining room temperature on the other. The room temperature has been regulated by a walk-in environmental chamber at the Geotechnical Laboratory of Università degli Studi di Roma Tor Vergata. To monitor the effects freeze-thaw cycles, temperature sensors and a linear variable displacement transducer (LVDT) have been used throughout the tests. Preliminary results indicate that the lower boundary temperatures accelerate the onset of frost heave and alter the position of the ice lenses. Additionally, an inverse relationship has been observed between soil density and frost heave susceptibility, with denser sand-kaolin mixtures exhibiting reduced volumetric effects compared to looser ones. Finally, the experimental findings are compared with an analytical model from the literature, which effectively predicts the position of ice lens.