The Wildlife stress-strain history during the Superstition Hills 1987 earthquake
The 1987 surface and downhole acceleration, and pore water pressure records were used to obtain direct estimates of Wildlife-Refuge site average seismic shear stress-strain and effective stress-path histories. These histories provided valuable insight into the site seismic behavior during liquefaction and associated loss of soil stiffness.
As the pore pressure increases due to seismic excitation, site stiffness is found to gradually decrease. During the high-pore-pressure phase, site behavior is characterized by cycles of large shear strain and very small shear stress. At these large strains, evidence of hardening response, possibly due to a dilative-type soil behavior, is observed.
The Wildlife stress-strain history during the Superstition Hills 1987 earthquake
31.30-47.50 sec , 44.50-86.25 sec
The Wildlife effective stress path history during the Superstition Hills 1987 earthquake
Click to view the effective stress path during stage 4.
The Wildlife shear strain-vertical effective stress history during the Superstition Hills 1987 earthquake
