Geometrical Deformation Analysis of Gotvand-Olya Dam Using Permanent Geodetic Monitoring Network Observations

  In this paper, two-dimensional deformation analysis of the Gotvand-Olya dam is done using daily, monthly, seasonal and annual displacement vectors derived from permanent observations of the dam geodetic monitoring network.  The strain tensor and its invariant parameters like dilatation and maximum shear are computed as well. Nonlinear finite element interpolation based on C1 Cubic Bezier interpolant function is used to compute the strain tensor in the Lagrangian approach. According to the results, the dilatations computed from the daily observations on March 25, 2014 and 2015 reveal the extension of dam, while on March 25, 2016 they indicate contraction in dam’s body and crown. Monthly results show the extension of dam’s geodetic network in September 2016 and contraction in September 2014 and 2015. Seasonal results showed the contraction in summer 2014 and extension in winter 2014 in dam’s geodetic network. Dilatation values from annual displacement vectors indicate contraction in dam from July 2014 to July 2015 and extension from July 2015 to July 2016. Statistical test is used to investigate the statistical significance of daily, monthly and seasonal strain tensor invariants.