The previous section has dealt with soil that is weakened during the earthquake due to liquefaction.
This section deals with granular soil that does not liquefy, but rather there is a reduction in shear
strength due to an increase in pore water pressure. Examples include sands and gravels that are below
the groundwater table and have a factor of safety against liquefaction that is greater than 1.0, but less
than 2.0. If the factor of safety against liquefaction is greater than 2.0, the earthquake-induced excess
pore water pressures will typically be small enough that their effect can be neglected.