Monitoring Movements at an Active Landslide in Western Pennsylvania: Application to Design and Implementation of a Stabilization Plan

Defining the limits and monitoring the movements of an active landslide are essential in the design, construction, and performance evaluation of a stabilization remedy. Landslide limits are often defined by an understanding of the subsurface stratigraphy and interpretation of field data. Landslide mass movements can be influenced by precipitation, local ground water fluctuations, or construction activities. The use of instrumentation to monitor and interpret movements during rehabilitation construction activities can provide: (i) an early warning of future potentially catastrophic movements; and (ii) the opportunity to optimize planned stabilization construction activities should unexpected movements occur. In this technical paper, the instrumentation monitoring system is described for an active landslide in western Pennsylvania where the stabilization plan was designed based on the location of the failure surface and measured movements. The instrumentation system used for assessing the failure was maintained and supplemented during construction. Data obtained from this instrumentation system will be presented, the use of the data to develop the stabilization plan will be demonstrated, and modification of the stabilization plan will be discussed. At the time of this paper, stabilization activities are ongoing; further refinement to the design may occur.