Seismic Performance of Soft Storey Reinforced Concrete Buildings in Ranau, Sabah Subjected to Design Seismic Load Stipulated in Malaysia National Annex to Eurocode 8

Staff quarters of S.M.K. Ranau and officer quarters of Hospital Ranau, which are the soft storey RC buildings, were severely damaged during a M6.0 Sabah earthquake on 5 June 2015 and were repaired in 2016. Following up, a M5.2 earthquake struck at Ranau, Sabah on 8 March 2018. Due to the buildings are non-seismically designed, the seismic performance of both buildings has not been assessed. Hence, this paper discusses the seismic performance of both buildings subjected to design seismic load stipulated in Malaysia National Annex to Eurocode 8. Computational analyses were performed using ETABS based on the architectural plans and on-site measurement. The simulation models were verified with the measured microtremor data. Seismic performance of both buildings under the design load were obtained by using modal response spectrum analysis. Under the design acceleration of 0.16 g, the maximum interstorey drift occurs at the first floor due to soft storey effect. The maximum interstorey drift for the staff quarters of S.M.K. Ranau has exceeded the damage limitation as specified in Eurocode 8, which is 0.005 mm/mm.