Abstract:
Rheological properties cause the stress-strain relationship of soil to have a time effect, which has a significant impact on the dissipation of pore pressure and the development of deformation during soil consolidation. Using the fractional derivative Merchant rheological constitutive model to consider the time effect of the stress-strain relationship of the soil skeleton, combined with Biot consolidation theory, a three-dimensional non-axisymmetric rheological consolidation model of saturated soil foundation under rectangular distributed load is constructed. The consolidation control equation of a half-space saturated soil foundation is established in a three-dimensional rectangular coordinate system. The control equation is transformed into an ordinary differential equation through double Fourier transform and Laplace transform. The analytical solution in the transformed domain is derived using the theory of ordinary differential equations, and the time-domain response at any location in the foundation is obtained through numerical inversion. The results show that the rheological properties of the soil skeleton have a significant impact on the instantaneous consolidation response during loading, with both instantaneous pore pressure and deformation significantly reduced, and a long period of pore pressure growth occurs during the initial loading stage. The rheological properties of the soil skeleton only affect the time path of the increase and dissipation of pore pressure during consolidation, but have no effect on the peak value of pore pressure. The rheological properties of the soil skeleton increase the lag in consolidation response of deep soil, which reduces the pore pressure difference when the soil is consolidated at different depths.