Road Weather Management Program
photos of lightning, trucks plowing snow, an empty road before a storm, and an evacuation
Office of Operations 21st century operations using 21st century technologies

Best Practices for Road Weather Management Version 2.0

Best Practices > Publications > Publication Titles

Title:

Triggering Mechanisms for the Garvin Landslide

Abstract:

Shallow landslides in natural occurring stiff clay deposits in highway road cuts are generally associated with longterm slope behavior and performance, and being triggered by heavy rainfall events. This paper investigates a slope failure in which the triggering mechanisms are much more complicated. The landslide occurs within a period of 42 months and 16 days from the end of the cut slope excavation. The overall climate has been dryer than normal over the past five years, yet numerous rainfall events happened during the 42 month and 16 day period. The site was investigated through surface surveys, continuously sampled auger and SPT borings, in-situ shear tests and stability analyses. The clay slope can be characterized as a stiff, very high plasticity, mottled, structured, and expansive clay. Backcalculated shear strengths approach a fully softened state, and are close to the residual shear strength. This analysis was based on the best fit slope stability of the failed slope geometry. The paper looks into the effect that soil suction has on reducing the mobilized shear strength at the time of failure, through a case history. Equations and assumptions developed in recent research were utililized to show the effect of soil suction on an infinite slope element.

Source(s):

86th Transportation Research Board (TRB) Annual Meeting, Oklahoma Department of Transportation. For an electronic copy of this resource, please direct your request to WeatherFeedback@dot.gov.

Date: 2007

Author:

Clarke, Nevels

Keywords:


Rain
Precipitation

PDF files can be viewed with the Acrobat® Reader®.
Office of Operations