Analysis of Alternative Landslides Remediation Measures Using Sliding Force Concept

摘要

A historical slope failure in the Cuyahoga County, Ohio has been treated several times. Remediation measures included the construction of crib wall in 1961, installation of piling in 1971, construction of new crib wall and drainage control in 1984, and construction of laterally loaded drilled shafts in 1989. The slope around the existing drilled shafts is stable. But deep failure of soils behind these drilled shafts appears to occur. Besides evidence of soil erosion poses a major concern on the safety of the slope. The initial remediation plan was to further increase the sliding resistance by constructing another row of drilled shafts to form a continuous lateral loaded wall of drilled shafts. With this design, a new group of lateral loaded drilled shafts will be constructed in-between the existing drilled shafts. This remediation not only requires high construction cost, but the effectiveness is uncertain. Slope stability analyses were conducted in this paper using the sliding force concept. From this, the loads carried by the existing drilled shafts were estimated. It was found that the existing drilled shafts, due to their locations in the slope, only carries a small amount of sliding loads. The construction of lateral loaded wall of drilled shaft was found not effective in stopping the trends of landslide. Based on slope stability analyses, an alternative way for slope stabilization was proposed that involved removing the existing crib wall combined with proper soil erosion control measures. This provides a much lower cost alternative to fix the problem.