| Summary: | 碩士 === 國立臺灣大學 === 土木工程學研究所 === 104 === This study explores the basal heave stability of excavations in spatially variable clays. It is shown that traditional stability analysis methods based on assumed prescribed slip curves cannot capture the phenomenon of a critical SOF. Therefore, Random finite element method (RFEM) is adopted to simulate the basal heave factor of safety (FSFEM).
In order to figure out the phenomenon of a critical SOF, FSFEM will be compared to the factor of safety estimated by slip circle method (SCM). It is evident that the mean value of FSFEM is significantly less than its nominal value at some worst-case SOF. It is also shown that owing to an assumed prescribed slip curve of SCM, SCM is not allowed to seek for the weakest slip curve. In this study, a “weakest link” model which is based on SCM is proposed. However the model is allowed the critical slip curve to seek for the weakest potential slip curve among potential slip curves. The weakest link model is able to capture the phenomenon of a critical SOF, both qualitatively and quantitatively.
|
|---|
