Certain soils lose their strength and behave like a liquid when saturated with groundwater and shaken during a strong earthquake. This phenomenon, called liquefaction, can result in settlement, lateral movement, or loss of bearing strength. Buildings and other structures resting on liquefied soils may tilt, crack, or even collapse entirely.
Subsurface exploration collects information about liquefaction potential from soil borings and cone penetrometer testing. Laboratory testing of samples determines the soil type, density and strength. The soil characteristics, groundwater conditions and seismic setting are used to analyze the potential for liquefaction at a project site.