A Master of Science thesis in Civil Engineering by Nader Essam Aly entitled, "Effect of Diverse Seismic Hazard Estimates on Performance and Overall Cost of RC Shear Wall Buildings in Dubai, UAE," submitted in January 2016. Thesis advisor is Dr. Mohammad AlHamaydeh. Soft and hard copy available.
During the last two decades or so, many iconic buildings have been built in Dubai as a result of the rapid economic growth. Unfortunately, several probabilistic seismic hazard studies are reporting substantially diverse estimates for Dubai seismicity. Additionally, the current minimum requirements of Dubai municipality are based on the 1997 Uniform Building Code (UBC'97) with a seismic zone that was recently upgraded following an earthquake in 2013. The aim of this research is to investigate and quantify the impact of the seismic design level on the structural performance and overall cost of contemporary RC Shear wall buildings in Dubai. Twelve reference buildings with heights varying from 6 to 12 stories are designed and detailed following 2012 International Building Code (IBC'12) standards. The buildings are designed with special/ordinary Reinforced Concrete (RC) shear walls for three seismicity levels representing the range of possible estimates in Dubai, namely the high, moderate and low estimates. The seismic performance of the reference buildings is evaluated using pseudo-static nonlinear (push-over) analysis as well as Incremental Dynamic Analysis (IDA). The nonlinear simulation is performed using fully detailed finite element models for the reference buildings. Construction cost and earthquake losses are evaluated and compared for the reference buildings in order to arrive at solid conclusions and sound recommendations. It is found that medium-rise and high-rise RC shear wall buildings are susceptible to significant higher-mode effects. Hence, the current design practice is recommended to account for and consider higher-mode effects and ultimately, trade-off between performance and cost. Furthermore, it is demonstrated that designing for a more conservative (high) seismic hazard level yields substantial enhancements in the overall structural performance. The resulting enhancements in seismic performance are found to outweigh the apparent increase in initial investment by significantly reducing repair and downtime costs. Finally, even when the use of ordinary RC shear walls is permitted by design code (at low seismicity levels), the utilization of special RC shear walls substantially improves the structural response. This structural response improvement is associated with marginal impact on initial investment and a noticeable reduction in repair and down time costs.