Design, component testing and application of the low-cost, robust, resilient, and sustainable pressurized sand damper for the protection of civil structures

October 31, 2024 | 1:30pm – 2:30pm EST

The response-modification devices are used extensively in civil structures and infrastructures, due to their ability to mitigate the movements that structures such as buildings, bridges and nuclear power plants may experience when they are subjected to vibrations, earthquakes and other natural hazards; as well as to dissipate the developed energy due to these events. Additionally, the increasing need for high-performance structures that meet current needs for immediate functionality has motivated the advancement and implementation of a variety of response-modification devices.

The topic of this presentation is partly motivated by the need to develop sustainable energy dissipation devices that do not suffer from oil leakage due to failure of their end seals and from displacement limitations; and partly from the need to develop a robust damper that consists only of traditional civil engineering materials (sand and steel). The design, testing, and characterization of an innovative, low-cost, long-stroke, fail-safe, sustainable energy-dissipation device, in which the material surrounding the moving piston – with an attached sphere on it – and enclosed within the damper housing is pressurized sand, are presented. The proposed device is simple, robust in harsh environments with either high or low temperatures and delivers a stable force-displacement behavior over a large number of cycles.

Presenter

Kostas Kalfas is an Assistant Professor of Civil Engineering at The University of Texas at Tyler. Dr. Kalfas received his Ph.D. Degree (2023) in Structural Mechanics and Earthquake Engineering from the Southern Methodist University, in Dallas, Texas. He holds a M.Sc. (2015) in Bridge Engineering from the University of Surrey in the UK, and a 5-year Diploma (2012) in Civil Engineering from the National Technical University of Athens in Greece. He has published more than 30 papers in archival journals and conference proceedings.

Kostas’ research interests include the development, analysis and design of response-modification devices for the protection of structures against natural and man-made hazards; the seismic resilience of buildings; and the strengthening and stability of temporary structures. He has worked as a site engineer and as a bridge designer in Greece, Germany and the UK, while he was the project leader for the design and construction of a block of seven ecological sanitation (eco-san) cubicles including a rainwater harvesting system for hand washing and cleansing in the Kumi Hospital in Uganda (2016-2019). Kostas is a Chartered Member of the Institution of Civil Engineers (CEng MICE) in the UK and a Member of Task Groups 1.1 ‘Improving Seismic Resilience of Reinforced Concrete Structures’ and 4.1 ‘Bearings & Joints’ of the International Association of Bridge and Structural Engineering (IABSE). He has been honored with several prizes and awards, including the O.H. Ammann Research Fellowship in Structural Engineering from the ASCE.