Serviceability Limit State Reliability Analysis of Pernio Railway Embankment

In this paper, serviceability limit state reliability analysis of a railway embankment on soft clay is conducted using probabilistic approach. The aim of this study is to evaluate how uncertainties in soil parameters and geometry affect the reliability of the design with respect to maintenance need assessment. The studied clay deposit is located in Pernio, Finland. Due to intensive laboratory testing, the coefficient of variation of geotechnical parameters for each clay layer could be estimated. Two performance functions were defined based on maximum settlement and maximum change in longitudinal gradient given in Finnish guidelines. In the settlement calculation, both primary and secondary consolidation were considered. According to the results, uncertainty in gradient changes is more critical and also more challenging to assess compared to uncertainty in total settlement. All in all, reliability analysis will clearly support the assessment of maintenance need.