Reliability based analysis of foundation settlement

摘要

This research was aimed at the development of a method that will assist in the processof calibration of load and resistance factors for service limit state with focus on thesoils of the South-East zone of Nigeria based on standard penetration test (SPT)results. Reliability analysis, expressed in the form of reliability index (β) andprobability of failure (Pf) were performed for foundation settlement using First OrderReliability Method (FORM) in MATLAB. The footings were designed for a 25 mmallowable settlement value as recommended in Eurocode 7 for serviceability limit state(SLS) design which is a conventional approach. Reliability indices were calculatedbased on the Burland and Burbidge foundation settlement prediction method. Resultsof the reliability analysis show that, as the variability of geotechnical properties at asite increases, larger values of settlement were obtained with a higher probability ofoccurrence. Sensitivity study indicated that the applied foundation pressure andcoefficient of variation (COV) of SPT N-value significantly affected the magnitude offoundation settlements.