Performance of tall reinforced concrete chimney structures in the 2010 Chilean earthquake

This paper describes the performance of four tall reinforced concrete chimneys which were subject to significant ground shaking during the 2010 Mw8.8 Chilean earthquake event. The chimneys were all recently constructed using the 'New Chimney Design' where the reinforced concrete chimney is designed for ductility in accordance with the CICIND code and the internal face is directly lined with the 'Pennguard Block' lining system. Such chimneys are expected to perform well under seismic loading due to their ductile behaviour and lightweight lining. Overall the 'New Chimney Design' performed very well under extreme earthquake ground shaking. The two northern power station chimneys of height 95m were subject to ground shaking with a PGV in the order of 100mm/sec, whilst the two southern power station chimneys of height 130m and 100m were located directly within the fault rupture zone region, with PGV in the order of 200-250mm/sec. All chimneys performed very well, with either no cracking or minor circumferential cracks with a maximum thickness of around 0.2mm. The paper provides an overview of the expected ground motion in the form of response spectra and compares the predicted and actual response behaviour of the chimney structures.