Project: Millennium Highway Roundabout

Date: June 2019

Location: Cul de Sac, St. Lucia

Tests Performed: CPTs

Description:

As part of the West Coast Rod Rehabilitation Project, GID was retained to undertake CPTs along the alignment of a new road embankment within the marsh grounds directly north of the Millennium Highway. the new road corridor was earmarked within virgin land. Water drainage was poor, as the area was waterlogged during the investigation, days after the most recent rainfall event.

Given the site conditions, CPTs were the perfect method of intrusive investigation for the site, as the static nature of the test minimised ground disturbance and the improved accuracy of the CPT over dynamic counterpart tests like the SPT, made it possible to constrain compressible layer thicknesses to the nearest centimeter.

Each CPT within the predominantly normalised clay site achieved a maximum depth of 25m, with dissipation tests conducted to determine soil permeability and compressibility.