Beitrag zur numerischen Analyse der Schädigungsmechanismen von Naturzugkühltürmen
Noh, Sam-Young; Meskouris, Konstantin (Thesis advisor)
Aachen : Publikationsserver der RWTH Aachen University (2002)
Dissertation / PhD Thesis
Aachen, Techn. Hochsch., Diss., 2001
In the present work the progressive damage process of natural draught cooling towers is analysed numerically. A non-linear composite material model for the reinforced concrete is formulated. Regarding the durability a special attention is paid to the cracking process and the determination of the crack width. Within the framework of the static analysis two existing large natural draught cooling towers are analysed considering the geometrical as well as the material non-linearity in detail. The modifications of the dynamic characteristics are identified by means of the natural frequency analysis. The structural damage is quantified by global damage indicators related to the natural frequencies of the cooling tower. The influence of the damage process on the increase of the wind excitation is assessed in consideration of the shifted natural frequencies in the VON-KARMAN wind spectrum. The analyses demonstrate that the shift of the dynamic system due to damage process leads to a progressive damage process in the structure.