Investigation the Deformations of Shahr-e- Bijar Dam During Impoundment

Document Type : Original Article

Authors

1 Department of Civil Engineering, Central Tehran Branch, Islamic Azad University, Tehran, Iran.

2 Department of Civil Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran.

Abstract

Dam monitoring is possible by instrumentation at critical points and measurement of various parameters such as pore pressure and deformations, i.e. settlement and displacement. In this study, the monitoring of Shahr-e-Bijar Reservoir Dam is investigated using instrumentation data and numerical analysis. A finite element software package called Plaxis is used for the numerical analysis. According to the results of analyses carried out by the program that are in good agreement with observations and instrumentation data, it can be concluded that these programs are very useful for analyzing and predicting the behavior of earth dams. In this study, a variety of instrumentations used in rockfill dams are introduced and common methods and instruments are examined for measuring various geotechnical quantities. The situation of Shahr-e-Bijar Dam, i.e. deformation and seepage, are analyzed using instrumentation data provided by settlement meters and extensometers, which is measured over a relatively long period, and the results of dam modeling via finite element programs. One of the most important steps of dam construction is operation management and maintenance of such projects after design and construction phases. Accordingly, the results of dam monitoring and back analysis are employed to express the importance of these steps as a significant goal of this study and a practical part of dam operation management and maintenance process is also presented by examination of the results of the instrumentation of an earth dam. In summary, two- dimensional numerical modeling of the dam and its foundation is carried out via Plaxis version 8.2 after monitoring the behavior of Shar-e-Bijar Dam based on the information recorded by instrumentation system of the project and the results of numerical modeling are interpreted and compared with those of dam monitoring. Mohr-Coulomb behavioral model must be applied in this research.

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