Modeling of moisture diffusion in crushed basaltic rock stabilized with cementitious binders

The prediction of moisture diffusion within the cementitiously stabilized materials is essential for assessing their shrinkage and associated cracking potential. A theoretical approach was presented for modeling of moisture loss during drying of cementitiously stabilized pavement materials. The moisture loss process was characterized by isotropic nonlinear diffusion theory. Laboratory experiments were undertaken to measure the material properties and characteristics that included the coefficient of moisture diffusivity and the humidity isotherm. Independent laboratory tests were undertaken to validate the theoretical approach adopted, and the experimental and predicted results displayed close agreement. The laboratory results indicated that as the drying progressed, the rate of moisture loss became slower, which can be explained by the reduction in the coefficient of moisture diffusivity with the decrease of moisture content. The humidity isotherms measured also indicated that the stabilized pavement materials appear not to dry significantly further after they reach a pore relative humidity of about 65%.