An analysis of a worldwide status for monitoring and analysis of dam deformation

Description

The primary role of dam deformation surveys is to examine regularly the conditions of the dam and its overall safety. The state of monitoring programs has been a growing concern by many countries and professional groups at the national and international levels. Canada is no exception. Canada’s dams are generally characterized as having poorly designed monitoring systems and inadequate instrumentation. Today, this is no longer considered justifiable. This research is one of a series of steps in an attempt to rectify this situation. It was initiated as the initial stepping stone to a formalized set of proposed guidelines form which monitoring specifications can be written for each individual dam. The work is based on a collection of material from questionnaire forwarded to 79 member organizations of the International Commission of Large Dams (ICOLD) and from available literature on the monitoring and analysis of dam deformation (mainly ICOLD Bulletins, and reports of the International Federation of Surveyors (FIG) Study Group on Deformation Measurements). One of the major conclusion of the survey is that Surveying Engineers have had very little involvement in dam deformation. One of the reason suggested is that Survey Engineers may not be promoting or educating themselves adequately in the field of dam deformation. Consequently, this lead to the subsequent objective: to take the initiative to attempt to improve this situation by providing junior Surveying Engineers with example of the major types of large dams (h >15m) and the basic principles on their behaviour, and the methods used to monitor and analyze their deformations. Some of the other key issues that have resulted from this research include: (1) there is obvious lack of communication and/or understanding amongst profession in the field of deformation, (2) the realization of the proposed monitoring guidelines is largely dependent on having a legislation in place to enforce monitoring of all large dams, (3) Canada is the single leading country in the development of a global integration technique which utilizes both geodetic and geotechnical observables into a simultaneous deformation analysis, and (4) the successful implementation of new developments in the field of deformation measurements supports the need to continue on using both geodetic and geotechnical means in modelling dam deformation. In support of the monitoring guidelines this research recommends the need for further studies to determine the frequency and accuracy requirement of the observables, and the minimum number and type of instruments that must be included in all the major types of large dams.