A spatial variability view of freeway-3 dip slope failure in Taiwan
Journal
Journal of GeoEngineering
Journal Volume
8
Journal Issue
1
Pages
1-10
Date Issued
2013
Author(s)
Abstract
During the investigation of a Freeway-3 (F-3) dip slope failure in Taiwan, it was found that the uncertainty involved in the spatial variability of material strength and groundwater condition had a significant influence on the stability analysis of the slope. This study aims to conduct a forensic analysis for the Freeway-3 case from the perspective of spatial variability of shear strength in the slope. Analysis results show that under the information available at the design stage (around 1995), the original design of the Freeway-3 dip slope has a fairly acceptable risk level if spatial variability is not considered. If spatial variability is properly considered, the risk level dramatically worsens. Together with the new evidence obtained in the 2010 forensic investigation, the risk level worsens to "hazardous". Spatial variability seems to be able to explain why there was a sudden increase in anchor loads during the construction stage in December 1997. In the premise that the critical weak layer has been identified, simple risk-based design steps are proposed in this study. These steps do not require detailed spatial variability analysis because the analytical equations regarding spatial variability has been calibrated in this study.
Type
journal article