Roy Whitlow Basic Soil Mechanics May 2026

The first auger samples told him what the contractor’s hurried senses had missed: a shallow lens of organic silt trapped between layers of denser sand and a surprisingly soft, dark clay beneath. Water collected in that lens after each rain, and when trucks rolled across the bridge, the saturated layer redistributed stresses unevenly. That explained the tilt, but it also raised a quieter concern — the new abutment, if founded without care, could trigger a deeper, slower failure as the clay consolidated.