On Monday 30th May, a seminar entitled “Performance-based Optimisation of Energy Dissipation Systems for Seismic Applications” held by Dr. Iman Hajirasouliha, Associate Professor in Structural Engineering and Leader of Earthquake Engineering Group (EEG) at the University of Sheffield (UK), will take place in room Fassò.

Abstract:

Energy dissipation devices are increasingly used for seismic strengthening of existing buildings or as efficient seismic resistant systems in modern construction. However, optimum design of these devices in multi-storey buildings can be a challenging task due to their complex behaviour and high computational costs. This study presents a practical multi-criteria performance-based optimisation framework for more efficient design of non-linear dampers under seismic loads. The proposed method is based on the concept of Uniform Distribution of Damage and can significantly reduce (up to 300 times) the computational costs compared to conventional optimisation methods such as Genetic Algorithm. To improve the convergence rate, an adaptive formulation is developed that is modified in proportion to the level of performance violation. The proposed method can be efficiently used to satisfy multiple performance objectives in line with performance-based design recommendations of current seismic codes. The efficiency of the framework is demonstrated for steel frames with non-linear viscous as well as RC frames equipped with a novel friction-based wall damper. It is found that the optimum damping distribution identified by the proposed methodology consistently leads to considerably lower local and global damage indices compared to the solutions with an equal-cost uniform damping distribution.

Speaker’s Biosketch:

Dr Iman Hajirasouliha is an Associate Professor in Structural Engineering and Leader of Earthquake Engineering Group (EEG) at the University of Sheffield, UK. He has over 20 years of research and consultancy experience in the fields of earthquake engineering, performance-based optimisation, light-weight structures, energy dissipation devices, and novel strengthening techniques, leading to over 150 refereed journal papers and 100 conference publications in these areas. He has been Principal or Co-investigator of over €9M EU and UK funded projects led by his group. Dr Hajirasouliha is a member of several national and international technical committees and research networks, including fib Task Groups 6.6 and 7.6 and IABSE Task Group 1.1. He is currently Associate Editor of Practice Periodical on Structural Design & Construction (ASCE), International Journal of Earthquake and Impact Engineering (IJEIE) and Frontiers in Built Environment (Earthquake Engineering Section).