A deformation monitoring system for a hydroelectric generating station

A deformation monitoring system was developed for the Warsak Hydroelectric Generating Station in Pakistan. The concrete gravity dam and powerhouse structures underwent major upgrade and repair work in the 1990s. The structures, subject to the effects of alkali-aggregate reaction, have been undergoing distortion since the time of construction in the 1950s. The monitoring system described here was designed to provide data on the geometrical nature of the deformation, to model and predict future structural deformation.;The structures were monitored in the past; the available data from those efforts has been analyzed and compared to the results of the current effort. The majority of the instrumentation used in the previous monitoring efforts, including a fully-automated geotechnical system, had been damaged or destroyed.;Geodetic and geotechnical instrumentation has been employed in the current system. As new equipment acquisitions were limited, some previous instrumentation was repaired and adapted for use in the current system. The author has developed software to support data collection and analysis. Field crews and engineers in Pakistan have been trained in the procedures and techniques of deformation monitoring and analysis.;Significant challenges arose during the implementation of the system, including difficulties with project organization, personnel qualifications, and budget restrictions. Despite this, a monitoring system has been implemented and has provided data suitable for analysis. The analysis of the results indicated that the deformation of the structures followed a general trend of expansion, while the surrounding land was stable.