The Effect of Soil-Structure Interaction on the Ductility Demand of Tall Reinforced Concrete Silos

Reinforced Concrete Silos may be classified as storage structures, generally used for storing coal, cement, food grains and other granular materials. The present day cement factories invariably opt for single or a battery silos to store the manufactured cement. The development of slip form method of casting of tall cylindrical reinforced concrete structures has resulted in rapid construction of silos. In current research, two samples of reinforced concrete silos of Abyek Cement Factory are chosen. By using accelerograms recorded on Rock, Dense Soil and Loose Soils (according to Iranian 2800 seismic code), scaled to Sa=1.5g, the proposed models are analyzed for three cases of Empty, 50% Full and 100% Full conditions, using Nonlinear Dynamic Analysis method, with consideration of Soil-Structure Interaction (SSI) effects. After completing the analyses, maximum inelastic displacements (Δmax), for all records of various soil types and models are summarized. Then by performing a “Modal Pushover Analysis”, the Yielding Displacement (Δy) of models are computed. Finally by using mentioned displacements, the Ductility Demand for all records and models are computed and the entire results are summarized and discussed.