This paper deals with the heat transfer analysis of the 63 years old and 60 metres high Moste concrete arch-gravity dam, located in NW Slovenia. The analysis was performed after a new sophisticated monitoring system had been established, making it possible to perform continuous measurements of the temperatures of the concrete, of the water, and of the surroundings of the dam, i.e. the air temperatures and the amount of solar insolation. An equation defining nonlinear and non-stationary heat conduction in the case of a two-dimensional space, for a homogeneous isotropic solid whose thermal conductivity is independent of temperature, was solved numerically by means of the finite element method, taking into account appropriate boundary conditions. The latter involved the effects of changing conditions of the surroundings (i.e. shading, convection, and solar radiation) during the analysed period of 15 consecutive clear days in the summer. The results show that the measured and calculated temperatures of the concrete at different locations, and at different depths, were in very good agreement.

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This study presents a procedure for modeling the heat transfer process in a concrete dam, taking into account the time-varying boundary conditions on the upstream and downstream sides of the dam (i.e., the water level of the reservoir, spillover, insolation, and shading) which affect the temperature conditions of the dam. The large concrete arch-gravity Moste Dam (in North West Slovenia) was analyzed, where an automated system for the measurement of concrete and water temperatures, and for the monitoring of meteorological effects, was installed. Thermal analyses (1D and 2D) for non-linear and non-stationary heat conduction through solids were performed using a finite element method (FEM) based program, TeEx, which was complemented by two specially developed programs for determining the effects of convection and insolation, considering also the effect of shading. A 15-day period was analyzed, as well as a period of one year. It was found that the results of the performed analyses fitted in well with the experimentally determined concrete temperature measurements. The results showed that at the insolated side of the dam, the temperature gradient was largest in a very narrow area along the concrete surface, but the temperature did not stabilize shallower than at a depth of about 6 m. As part of the thermal analyses, uncertainty analyses of the results of the calculations were also performed.

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In this study, a large arch-gravity Moste Dam was analyzed, where an automated system for the measurements of horizontal displacements of the upper part of the dam was established. Two-dimensional (2D) and three-dimensional (3D) analyses of dam behavior, taking into account the earth pressures and the hydrostatic load, using the finite element method (FEM)-based computer program DIANA, were performed. The influence of lowering the water level of the reservoir by 6.2 m, on the horizontal displacements of the upper part of the dam, at stationary temperature conditions, was investigated. It was found that the results of the performed 2D and 3D FEM analyses fitted in very well with the result of experimentally determined measurement of horizontal displacements (which was 0.48 mm in the upstream direction) that was obtained using a hanging pendulum. An additional comparison of the results of 3D calculations showed that the finite element mesh density had a small effect on the calculated horizontal displacements.