There are safety concerns related to operation of heavy equipment over coal combustion residual (CCR) impoundments during construction of the impoundment closure programs. As part of a pilot study prior to a full-scale closure construction, an access pathway and working platform were designed and constructed to facilitate equipment access for construction of deep soil mixing (DSM) zones on the ash delta of a CCR impoundment. The access pathway and working platform was constructed using shallow mass mixing with cement at the CCR surface to address safety concerns related to the geotechnical behavior of CCR. This paper describes the data from the instrumentation system which was implemented to monitor the geotechnical performance of the CCR during the pilot study. The instrumentation system included monitoring of the ground movement, vibration, and porewater pressure within the ash delta of the CCR impoundment during a pre-construction load testing, equipment mobilization over the access pathway, and DSM column installation over the working platform.
Subjects: performance monitoring, working platform, CCR impoundment, deep soil mixing
Author: Amir Ahmadipur, Ali Ebrahimi, PhD., P.E., Roneet Das, William Tanner, P.E., Paul J. Sabatini, Ph.D., P.E., D.GE, Jeremy M. Gasser, P.E. and Cuneyt Gokmen, P.E.