Model for Coupled CRS Consolidation and Contaminant Transport

Abstract

This paper describes the development of a numerical model, called CSTCRS1, for one-dimensional coupled contaminant transport and large strain consolidation under constant rate of strain (CRS) loading conditions. Numerical simulations using CSTCRS1 indicate that concentration boundary conditions can have an important effect on contaminant transport during CRS consolidation. For the conditions considered, zero concentration gradient and reservoir boundary conditions yielded the same contaminant mass outflows regardless of the transport mechanisms (i.e., diffusion, mechanical dispersion, and sorption). However, these transport mechanisms become important when a zero concentration boundary condition is specified. Additional simulations indicate that applied strain rate also has an important effect on the coupled CRS consolidation and contaminant transport. A higher strain rate will generally yield more non-uniform local strain profiles, smaller contaminant mass outflow, and a larger concentration gradient within specimen.