When determining the displacements of control points installed on a structure or on the surrounding terrain, it is important to use well-stabilized reference points that remain stable between successive measurements. In practice, these points are often stabilized in the natural environment, where they are exposed to changing conditions. The stability of a reference point significantly influences the accuracy of geodetic measurements. In addition to the various ground movements, the position of these points, often stabilized by pillars, is also affected by thermal load caused by solar radiation. Such thermal effects can lead to displacements of the measuring pillars, leading to shifts the screw for forced centering mounted at the top of the pillar, which serves as an attachment point for an instrument or reflector. If such a pillar or point is used for measurements, the displacement of the pillar can lead to errors in the measured lengths or horizontal directions. The impact of temperature-induced differences within the pillar, caused by solar radiation, on the position of the screw for forced centering for attaching the instrument or reflector can be significant and cannot be ignored in geodetic precision measurements. The doctoral dissertation addresses the thermal influence on reinforced concrete pillars used for stabilizing reference points and the consequences of these deformations on measurement accuracy. We developed a computational model to predict displacements caused by thermal loads. The results of the computational model were compared with the results obtained from a laboratory experiment, and we analyzed the influence of errors due to pillar displacements on precise geodetic measurements. Under controlled laboratory conditions, we heated the pillar from one side while simultaneously measuring displacements, rotations, and temperatures. Based on the results of the laboratory analyses, we determined the temperature distribution within the pillar and evaluated the suitability of an indirect method for determining the displacement of the top of the pillar from measured rotations near the top of the pillar. The results demonstrate that this indirect approach with inclinometers offers a practical and reliable alternative to direct displacement measurement using displacement sensors, especially in field applications where methods based on displacement sensors are difficult to implement.
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