Dam Safety: the search for innovative tools

Dam safety assessments rely on the skill and experience of dam engineers but such expertise is not always easily transferred to new staff or conveyed in written reports. Many old dams have outlived their creators and puzzle those that see them for the first time. Eliane Alves Portela and Joao Bento explain how expert system technology can help avoid this DAM construction started over 2000 years ago and has presented the engineering community with significant challenges throughout the twentieth century. Dams have been built all over the world to satisfy a range of human needs, and the acquired experience has led to improvements in analysis, testing, construction and monitoring techniques, with subsequent progress in dam safety. Looking at the present stage of development, dam engineering has achieved a high level of sophistication. Continual advances in information and communication technologies have a profound effect on the way engineers tackle problems. Both the technology itself and the expectations of end-users are pushing towards new developments in engineering systems, making use of a variety of innovative tools. This article takes a closer look at one such tool – expert system technology – which has already emerged in other domains and can be used to improve the overall cycle of dam safety control. A safe dam is one that provides people and property with an acceptable level of protection against its failure or overtopping without failure, and which meets safety criteria set as standard by the engineering profession. The safe control of a dam is defined as the set of measures taken in various stages of the dam's life. These consider structural, hydraulic, operational and environmental aspects, with a view to adequate and continuous knowledge of the state of the dam, timely detection of any anomalies and efficacious intervention whenever necessary (RSB, 1990). A systematic evaluation of the safety of the dam should be carried out throughout its whole life cycle. This can be done by means of a comprehensive inspection on the structure, involving the collection of all available dam records, field inspection, detailed investigations and possibly laboratory testing, followed by its performance assessment and review of the original design and construction records to ensure that they meet current criteria. The level of detail required for its evaluation should be commensurate with its importance, design conservatism and complexity, as well as with the consequences of failure. Dam monitoring plays a vital role in …