Spectral Acceleration Amplification Effects on The Ductility Demand of Self Standing R.C. Chimneys

According to construction of industrial structures in developing countries, current research is carried out on Self Standing Reinforced Concrete Chimneys, which are a sort of special structures and is used in several types of factories. For this purpose, the 3D model of an existing Reinforced Concrete chimney of 80.0 m high and a diameter of 4.0 ~5.0 m in Armenia, is modeled and analyzed using spectral analysis procedure according to 4th revision of Iranian 2800 seismic code, taking into account the spectral acceleration level to Sa=0.4g. On the next step, the finite element model is analysed by the means of Time History Analysis method, using 3 pairs of accelerograms recorded on each soil categories of Rock (Vs gt;750m/s), Dense Soil (375 lt;Vs lt;750m/s) and Loose Soil (175 lt;Vs lt;375m/s) and Very Loose Soil (Vs lt;175m/s) respectively, taking into account the spectral acceleration level of Sa=0.2g ~1.0g. The Modal Pushover Analysis is carried out as well in order to determine the Yielding Displacment Δy. Finally the ductility demand for all soil categories are computed.