Seminar on Self-Centering Low-Damage Seismic Structural Systems and Post-Earthquake Fire Response of Steel Building Structures
Itinerary 20th May 2015 Seminar Room 1, Undercroft
0900-0930: Registration
0930-1030: Lecture 1
1030-1100: Break
1100-1200: Lecture 2
ABOUT THE SPEAKER
Dr. Pessiki has conducted research and teaches courses in areas of behavior and design of structures; nondestructive evaluation of materials and structures; fire effects on structures; earthquake engineering; and innovative building materials and systems. Dr. Pessiki has worked on numerous funded research and laboratory experiment projects. His findings have been published in dozens of conference proceedings and journal publications, in addition to book chapters and technical reports.
Dr. Pessiki is a member of the Precast/Prestressed Concrete Institute (PCI), which awarded him the Leslie Martin Award of Merit in 2006. PCI named Pessiki a Fellow and a Distinguished Educator. He is also a Fellow of the American Concrete Institute. Other honors and awards include Lehigh teaching and service recognition as well as Drexel University's Distinguished Alumni Lectureship, a fellowship from the Japan Society for Promotion of Science, honorary membership in the Brazilian Society of Structural Engineers, and a best paper award from ASCE Journal of Architectural Engineering.
Dr. Pessiki has experience at a variety of prestigious schools. He was a visiting professor at Perdue University, post-doctoral associate and research assistant at Cornell University, and visiting assistant professor at Syracuse University. Prior to his career in higher education, Dr. Pessiki worked as a structural engineer for the architectural firm Kling-Lindquist Inc., which has since evolved into Kling Stubbins. He is a member of the American Concrete Institute (ACI), the American Society of Civil Engineers, the American Society for Engineering Education, the American Society for Nondestructive Testing, the Earthquake Engineering Research Institute, the Society of Fire Protection Engineers, and The Masonry Society. He is also a member of Tau Beta Pi and Chi Epsilon.
Lecture 1: The Evolution of Self-Centering Low-Damage Seismic Structural Systems – Concept, Research and Implementation in Practice
Traditional design of seismic resistant systems for building structures have often relied on structural damage (e.g. yielding of steel, non-linear compression response of concrete, etc.) as the intended response of the structure to limit the increase in lateral force and to dissipate energy. The goal of this traditional design approach was life-safety, i.e. to prevent building collapse. Following this approach, a major seismic event can cause significant damage to the structure. This in turn requires extensive repair, or if the damage is severe enough, for the structure to be demolished. More recently, an alternative design approach has emerged that is intended to provide structures that remain damage free and self-center (i.e. exhibit no residual drift) after the earthquake. This presentation describes this alternative approach, reviews some of the research performed on a variety of structural systems in steel and concrete structures, including the results of recent large-scale tests of cast-in-place concrete walls, and presents examples of the implementation of these self-centering low-damage seismic structural systems in actual building structures.
Lecture 2: Post-earthquake Fire Response of Steel Building Structures –Recent Research at Lehigh University
Current building design practice in the United States uses a combination of active and passive fire protection systems to provide structural fire protection in multistory steel buildings. Active fire protection systems include sprinklers and firefighters. Passive fire protection systems are those built into the building system that do no require specific activation, such as sprayed fire-resistive materials (SFRMs). Sprinklers and other active systems are intended to extinguish a fire or to limit its spread, and SFRM is intended to thermally protect structural steel elements during a fire. Past events have demonstrated that earthquakes can cause fires in buildings, damage active fire protection systems such as sprinklers, and reduce the effectiveness of fire-fighting capabilities. In such an event where the active fire protection systems are compromised by an earthquake, passive systems such as SFRM may remain the only available means to mitigate the effects of the fire on the structural system in a building. However, during an earthquake, the integrity of the SFRM may become compromised because of damage to the underlying steel structure to which the SFRM is bonded. For example, for traditional strong-column weak-beam designs, large deformation demands are place on the beams in the vicinity of the columns, which in turn place large demands on the ability of the SFRM to remain attached to the beams. Gravity load frames undergo the same lateral drift as the lateral force resisting frames, and thus are also susceptible to structural damage and damage the SFRM. This presentation discusses the results of recent experimental and analytical research at Lehigh University on the post-earthquake fire scenario in steel frame building structures.
