COMPARISON OF STRUCTURAL RESPONSE OF TRADITIONAL AND STRENGHTENED REINFORCED CONCRETE MINARETS

Numerous destructive earthquakes occurred in Turkey in recent years. Many minarets were damaged or collapsed during these catastrophic events resulting in loss of life in some cases. Minarets are generally constructed without a detailed lateral analysis or construction permit. Furthermore, there is no official guideline or code governing the design of these special slender structures. As a result, the level of seismic damage sustained by the minarets is usually associated with the selected structural configuration, construction quality and experience of construction workers. The main objective of this study is to compare two structural systems used for reinforced concrete minarets subjected to earthquake loads. One of the structural systems is very common and includes cylin drical minaret body. The other, a relatively recent one, has buttressed or propped up polygonal body. The minarets are modeled using the finite element method with design spectra and acceleration histories recorded during the August 17, 1999 Kocaeli and 12 November 1999 Düzce, Turkey earthquakes. The calculated displacement response and local stress concentrations for the two minarets are briefly discussed and illustrated.