Polk County Expressway: A Laboratory, Numerical, and Field Study of Consolidation.

Expansion of the Florida Turnpike in Polk County involved construction over reclaimed phosphatic clay deposits. This paper presents the laboratory tests, numerical analyses, and field monitoring of the consolidation process. The laboratory tests involved oedometer tests prior and during surcharging, and constant rate of strain tests to evaluate permeability versus void ratio. The numerical work considered two-dimensional small versus large deformation theory using a coupled mixture approach. Both theories employed a modified cam-clay with a hyperelastic constitutive model; the field study monitored settlements and pore pressure from settlement plates, settlement cells, and piezometers. It was discovered that both small and large deformation theory did a good job in predicting the laboratory consolidation process, however, the large deformation theory predicted the field response better, especially for the deeper deposits (i.e., over 6 m), which was attributed to its updating geometry influences on pore pressures and effective stresses from coupled mixture theory. [ABSTRACT FROM AUTHOR]