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Heat transfer within the soil is a complex process in the presence of seepage flow. In such conditions, the soil’s thermal behavior is influenced by the thermal and hydraulic properties of the medium as well as the initial conditions and boundary conditions to which the medium is subjected. This paper presents the experimental and numerical studies of heat transfer within the sand subjected to the seepage flow. It focuses on the influence of saturated hydraulic conductivity and the porosity of medium on the heat transfer process. The temperature distribution within the sand was monitored by the optical fiber Distributed Temperature Sensor (DTS). The experiment was performed on three types of silica-dominated sands with different saturated hydraulic conductivities and different Soil Water Characteristic Curve (SWCC). In addition to the experimental study, a coupled hydrothermal numerical model was designed in FEFLOW software and validated by comparing its results with the experimental measurements. To determine the influence of porosity and saturated hydraulic conductivity on heat transfer, we analyzed the numerical models for different values of porosity and saturated hydraulic conductivity. The numerical and experimental studies showed that the thermal velocity is higher in sand with higher saturated hydraulic conductivity and temperature declination occurs more quickly due to the heat convection process. Saturated sand with larger porosity has an overall higher heat capacity, wherefore the temperature declination started later in the measuring points but dropped down lower close to the temperature of the upstream water. Přenos tepla v půdě je složitý proces za přítomnosti prosakujícího toku. Za takových podmínek je tepelné chování půdy ovlivněno tepelnými a hydraulickými vlastnostmi média, jakož i počátečními podmínkami a okrajovými podmínkami, kterým je médium vystaveno. Tento článek představuje experimentální a numerické studie přenosu tepla v písku vystavenému průsakovému toku. Zaměřuje se na vliv nasycené hydraulické vodivosti a pórovitosti média na proces přenosu tepla. Distribuce teploty v písku byla monitorována snímačem distribuované teploty z optického vlákna (DTS). Experiment byl proveden na třech typech písků s převahou oxidu křemičitého s různými nasycenými hydraulickými vodivostmi a odlišnou charakteristickou křivkou půdy (SWCC). Kromě experimentální studie byl v softwaru FEFLOW navržen spojený hydrotermální numerický model a ověřen porovnáním jeho výsledků s experimentálními měřeními. Abychom určili vliv pórovitosti a nasycené hydraulické vodivosti na přenos tepla, analyzovali jsme numerické modely pro různé hodnoty pórovitosti a nasycené hydraulické vodivosti. Numerické a experimentální studie ukázaly, že tepelná rychlost je vyšší v písku s vyšší nasycenou hydraulickou vodivostí a pokles teploty nastává rychleji v důsledku procesu tepelné konvekce. Nasycený písek s větší pórovitostí má celkově vyšší tepelnou kapacitu, proto pokles teploty začal v měřicích bodech později, ale klesl dolů níže blízko teploty vody proti proudu.

The paper presents the design and static analysis of a high arch dam. A feasibility study was conducted on the dam in the 90s and a preliminary layout was designed. However, the dam’s construction phase has been never started. In this paper, the design and layout of the dam under consideration are in accordance with the US manuals for the design of arch dams. The structure’s three-dimensional model was entered into the program SAP2000 and three-dimensional solid finite elements were used to discretize the model. This paper considers the hydrostatic pressure of the water reservoir and concrete self-weight. The analysis was performed for both the maximum and the minimum designed water level and for the case when the reservoir is empty. Special attention is given to the boundary conditions of the dam at its abutments and foundation. The results show that the planned layout is good for the dam’s construction. The arch dam’s curve transfers the loads to the abutments. The significant role of the foundation rigidity and the reservoir water level in the stress distribution and nodal displacements within the arch dam is observed.