A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
Liquefaction, Ground Motions, and Pore Pressures at the Wildlife Liquefaction Array in the 1987 Superstition Hills Earthquake
One of the most valuable liquefaction case histories is that of the Wildlife Liquefaction Array (WLA) in the November 23–24, 1987 Elmore Ranch and Superstition Hills earthquakes. The WLA site contained a vertical array with accelerometers at the ground surface and at 7.5 m depth, and six piezometers. Five of the piezometers were in a layer of loose, silty sand that extended from about 2.5 to 6.5 m depth and the sixth was in a layer of silt at 12 m depth. The groundwater table was approximately 1.5 m deep. On November 23, 1987, the Elmore Ranch (M6.2) earthquake produced moderate shaking but no surficial evidence of liquefaction at the WLA site. The next day, the Superstition Hills (M6.6) earthquake produced surficial evidence of liquefaction in the area of the strong motion instruments. Recorded pore pressure measurements, however, were considered by some to be inconsistent with the recorded ground motion measurements leading to published discussions that described significant technical disagreements in the geotechnical earthquake engineering literature. Recently developed time-frequency analyses and nonlinear effective stress site response analyses can offer new insight into the WLA response during the Superstition Hills event. This paper reviews the conditions and measurements at the WLA site, and the arguments that support and criticize the accuracy of the pore pressure measurements. It then presents time-frequency and site response calculations that clarify the response at the WLA array, and illustrate how such calculations can be used to better interpret liquefaction at vertical array sites.
Liquefaction, Ground Motions, and Pore Pressures at the Wildlife Liquefaction Array in the 1987 Superstition Hills Earthquake
One of the most valuable liquefaction case histories is that of the Wildlife Liquefaction Array (WLA) in the November 23–24, 1987 Elmore Ranch and Superstition Hills earthquakes. The WLA site contained a vertical array with accelerometers at the ground surface and at 7.5 m depth, and six piezometers. Five of the piezometers were in a layer of loose, silty sand that extended from about 2.5 to 6.5 m depth and the sixth was in a layer of silt at 12 m depth. The groundwater table was approximately 1.5 m deep. On November 23, 1987, the Elmore Ranch (M6.2) earthquake produced moderate shaking but no surficial evidence of liquefaction at the WLA site. The next day, the Superstition Hills (M6.6) earthquake produced surficial evidence of liquefaction in the area of the strong motion instruments. Recorded pore pressure measurements, however, were considered by some to be inconsistent with the recorded ground motion measurements leading to published discussions that described significant technical disagreements in the geotechnical earthquake engineering literature. Recently developed time-frequency analyses and nonlinear effective stress site response analyses can offer new insight into the WLA response during the Superstition Hills event. This paper reviews the conditions and measurements at the WLA site, and the arguments that support and criticize the accuracy of the pore pressure measurements. It then presents time-frequency and site response calculations that clarify the response at the WLA array, and illustrate how such calculations can be used to better interpret liquefaction at vertical array sites.
Liquefaction, Ground Motions, and Pore Pressures at the Wildlife Liquefaction Array in the 1987 Superstition Hills Earthquake
Kramer, Steven L. (author) / Sideras, Samuel S. (author) / Greenfield, Michael W. (author) / Hushmand, Behnam (author)
Geotechnical Earthquake Engineering and Soil Dynamics V ; 2018 ; Austin, Texas
2018-06-07
Conference paper
Electronic Resource
English
| British Library Conference Proceedings | 2018
Effect of earthquake ground motions on soil liquefaction
| British Library Online Contents | 2012
Ground Motions Estimates for a Cascadia Earthquake from Liquefaction Evidence
| British Library Conference Proceedings | 1998
Ground Motions Estimates for a Cascadia Earthquake from Liquefaction Evidence
| British Library Conference Proceedings | 1998
Ground Motions and soil liquefaction during earthquakes
| TIBKAT | 1982