The Stuttgart TV Tower — displacement of the top caused by the effects of sun and wind

The monitoring of static, quasi-static and dynamic deformations of long-period structures is now possible using Global Positioning System (GPS) technology. This paper describes the way in which the Stuttgart TV Tower was monitored using static and kinematic GPS modes. The displacements of the tower were caused by two factors. Quasi-static displacements were caused by the combined influence of solar radiation and daily air temperature variation during different weather seasons and conditions. Dynamic displacements were caused by wind. The results clearly demonstrate that the procedure using GPS measurements allows us to collect displacement data which could be used to determine the displacement thresholds of the tower and/or to examine the changes of vibration characteristics. This data was valuable for the assessment of the integrity and reliability of the tower.