Abstract

The authors present a solution realized in Forest Opera (name in Polish: Opera Leśna) in Sopot (Poland) in connection with the modernization and construction of a new roof. The complicated structure of the roof of the facility and the used covering in form of membrane made of technical fabric required (for security reasons) to install the unit of devices allowing for the continuous geodetic monitoring of the facility. Monitoring of relocations in case of engineering structures of a complex design allows for the extended safety of their use. Realized (for this purpose) geodetic measurements require (to be useful) a high accuracy, full automation making the assessment independent from the human factor and the use of reference points. The main element of the presented system is a motorized total station used for the determination of roof cover relocations, whereas the complementary elements are vibration and temperature sensors and weather conditions monitoring station. Data recorders from the entire facility are connected to the computer central unit, providing automation of measurements and archiving of results along with their analysis. The problem occurring in the analyzed object is relatively unstable (subject to vibration) total station. Therefore, the solution implemented for Opera Leśna in Sopot assumes, that it is required to carry out measurements against reference points before every measurement of controlled points. On the basis of these measurements, for each measurement epoch the coordinates and relocation vectors for the tachymeter station are checked as well as analyses of an accuracy suitable for this process. The solution of this problem is useful for monitoring in other movable or subject to relocation engineering facilities. The article signalizes the problem of accuracy of surveying. For this purpose, the preliminary analyses of an accuracy were carried out. They made it possible to determine the expected errors of the reference points location in the designed network geometry and position of the total station for two variants: with and without taking into account the erroneous of reference points location. To summarize, we can say that the automatic measurement systems are an appropriate method for the continuous observation of the construction condition, however, they must be based on accurate, repeatable (for each measurement epoch) analyses of the observation of both monitored elements as well as their spatial references.

Citations

Authors (5)