Performance based design in geotechnical earthquake engineering

The key elements of performance-based design will be illustrated and discussed in the context of designing cost effective remedial measures for embankment dams with liquefiable materials in the foundation. This situation is considered one of the more challenging areas of performance based design. Some of the key elements that will be considered will be the selection of performance criteria, selection of an appropriately validated analysis program and calibrating the constitutive model to represent material properties in the field. Major elements of performance based seismic design will be explored using typical case histories from practice such as Sardis Dam in Mississippi, Mormon Island Auxiliary Dam in California, and Flood Protection Dikes in Hokkaido, Japan. A primary source of concern about performance based design based on the results of finite element or finite difference methods of analysis is the reliability of the analyses. Reliability is enhanced by due diligence in the selection of a well-validated program and an appropriately calibrated constituted constitutive model. These issues are discussed in the paper, but there remains a residual concern because there is no field response data on large dams by which our real capability can be assessed.