Practical geotechnical application of reliability methods

摘要

What is an acceptable safety factor? Why is it usually associated with strength and not geometry or pore pressure? Reliability analysis places decision making in a rational framework, and it is now beginning to affect geotechnical practice. Three case studies are discussed. The first involved three embankment designs showing that expected values of the factors of safety were in inverse order to their reliability. The analysis yielded target values of factor of safety and revealed parametric sensitivities. The second involved a slope in Karst for which no conventional stability analysis was appropriate. Statistical analysis of observed failures led to a decision among proposed remediation schemes. The third case involved the liquefaction potential for an oil storage tank farm located on filled land. The analysis ranged from seismic hazard analysis to the use of F-N plots to display results. Management decided to proceed with a multi-million dollar program of groundwater control.