抄録
The deformation behaviour and wave velocity variation of Tage Tuff, a transversely isotropic sedimentary rock, during desiccation in controlled environment was investigated in order to determine its deformation characteristics and elastic parameters. Strain as well as compressional (P) and shear (S) wave velocities were measured in a set of cylindrical Tage Tuff specimens cored across and along the bedding plane. Then, five independent dynamic engineering constants of transversely isotropic Tage tuff were calculated using the measured wave velocities and density during drying.Strain, P wave velocity and dewatering rates were sensitive to the degree of saturation as well as measured direction with respect to the bedding plane. Rapid increase in shrinkage as well as P and S wave velocities in below 35% saturation level occur due to the desiccation-driven hardening of Tage tuff. In relation to the calculated Young's and shear moduli variation with desaturation, we can conclude that the drying process strengthen the Tage tuff. Moreover, sensitivity of P wave velocity variation pattern with saturation according to the bedding direction gives an insight into the understanding of the water/air distribution within a transversely isotropic rock during desiccation.
