For surveillance purposes, we have been monitoring the stability of existing facilities, during construction of the Unit 6 cooling tower of the thermal power plant Šoštanj. To this end, an automated monitoring network has been established on the Unit 4 cooling tower (TEŠ 4).
Three GNSS observation points on top of the upper perimeter of the cooling tower give us a collection of data (measurements) within a specified time interval. 36 initial measurements have been monitored for each month in the period between September 2010 and October 2013.
To calculate the center and radius, we use the measured coordinates of peripheral points and compute the intersection of the ground plane with the two bisecting planes, derived from the centerlines of adjacent points and calculated according to the rules of projective geometry, using the Excel UDF.
The aim is to have as accurate measurements and related calculations as possible, therefore having them being made in the same (complex) conditions with multiple repetitions, using the least squares method. By using analytical methods, in particular the above-mentioned method of least squares, we will analyze the data and results of peripheral points, the center and the radius.
We are primarily interested in: the most probable point coordinates represented by the arithmetic mean, the largest ranges of deviations, standard deviations and an evaluation of accuracy.
The data obtained are necessary for the continuous active monitoring of movements in real time and thereby enabling an immediate and effective response to the stability and security of built and existing facilities.