{"622744":{"#nid":"622744","#data":{"type":"event","title":"Phd Defense by Pablo Vega-Bahar","body":[{"value":"\u003Cp\u003E\u003Cstrong\u003ESchool of Civil and Environmental Engineering\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003EPh.D. Thesis Defense Announcement\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003ESeismic Assessment and Dynamic Testing of Reinforced Concrete Frames Retrofitted with a Shape-Memory Alloy Brace System\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003EBy\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003EPablo Vega-Behar\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003EAdvisor:\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003EDr. Reginald DesRoches (CEE) \u0026amp; Dr. Roberto T. Leon (Virginia Tech)\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003ECommittee Members:\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003EDr. C.S. Walter Yang (CEE), Dr. David W. Scott (CEE), Dr. Richard W. Neu (ME)\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003EDate \u0026amp; Time:\u003C\/strong\u003ETuesday, July 9, 8:00am\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003ELocation:\u003C\/strong\u003E Mason 2119\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003ERegion-level seismic risk assessments have estimated the economic and life-safety impact of a large\u003Cbr \/\u003E\r\nmagnitude earthquake in the US New Madrid Seismic Zone at over $300 billion dollars and close to\u003Cbr \/\u003E\r\n100,000 casualties, respectively. Seismic rehabilitation of structures has been a research priority for the\u003Cbr \/\u003E\r\nlast 2 decades to address safety of older structures. Non-ductile reinforced concrete (RC) frame structures\u003Cbr \/\u003E\r\nhave been a focus of much of this research due to their prevalence in the Central and Eastern US.\u003Cbr \/\u003E\r\nHowever, prior research and existing solutions have several limitations. Regarding experimental research,\u003Cbr \/\u003E\r\nmost prior tests fail to capture the interaction of multiple components in a full structural system, or the\u003Cbr \/\u003E\r\nstudies involve reduced scales that do not appropriately replicate critical resistance mechanisms. For\u003Cbr \/\u003E\r\nexisting retrofit solutions, these have been effective in increasing life-safety for occupants but they typically\u003Cbr \/\u003E\r\nsustain levels of damage that render them irreparable, which fails to address economic impacts. In\u003Cbr \/\u003E\r\naddition, their construction is typically invasive, which may disrupt building occupants and operations.\u003Cbr \/\u003E\r\nThus, this research attempts to address these limitations by proposing a retrofit solution that is reusable,\u003Cbr \/\u003E\r\nself-centering, and has a minimally invasive construction and installation procedure. The retrofit was tested\u003Cbr \/\u003E\r\ndynamically in a full-scale system to overcome the limitations of prior, reduced-scale experimental testing\u003Cbr \/\u003E\r\nresearch. Experimental and analytical results showed that the SMA bracing device effectively reduced\u003Cbr \/\u003E\r\ninter-story drifts compared to a non-retrofitted frame. The retrofitted test structure showed minimal damage\u003Cbr \/\u003E\r\nat demand levels that would have collapsed the original structure. Numerical results indicate that the SMA\u003Cbr \/\u003E\r\nbrace retrofit significantly reduces the probability of exceeding all damage states at given spectral\u003Cbr \/\u003E\r\naccelerations. Most notably, the probability of exceeding the complete damage state was reduced from\u003Cbr \/\u003E\r\n50% (as-built) to less than 2% (SMA brace retrofit) at a 0.78g spectral acceleration. The design and\u003Cbr \/\u003E\r\nassembly steps for experimental testing suggest that this retrofit can be beneficial in practical applications\u003Cbr \/\u003E\r\nwhere disruptions to building occupants are a concern. The retrofit design procedure, its behavior and response to all test loads, a qualitative evaluation of the design method, seismic risk performance\u003Cbr \/\u003E\r\nassessment, and implications on future research are discussed\u003C\/p\u003E\r\n","summary":null,"format":"limited_html"}],"field_subtitle":"","field_summary":"","field_summary_sentence":[{"value":"Seismic Assessment and Dynamic Testing of Reinforced Concrete Frames Retrofitted with a Shape-Memory Alloy Brace System"}],"uid":"27707","created_gmt":"2019-06-24 18:56:57","changed_gmt":"2019-06-25 12:13:28","author":"Tatianna Richardson","boilerplate_text":"","field_publication":"","field_article_url":"","field_event_time":{"event_time_start":"2019-07-09T09:00:00-04:00","event_time_end":"2019-07-09T11:00:00-04:00","event_time_end_last":"2019-07-09T11:00:00-04:00","gmt_time_start":"2019-07-09 13:00:00","gmt_time_end":"2019-07-09 15:00:00","gmt_time_end_last":"2019-07-09 15:00:00","rrule":null,"timezone":"America\/New_York"},"extras":[],"groups":[{"id":"221981","name":"Graduate Studies"}],"categories":[],"keywords":[{"id":"100811","name":"Phd Defense"}],"core_research_areas":[],"news_room_topics":[],"event_categories":[{"id":"1788","name":"Other\/Miscellaneous"}],"invited_audience":[{"id":"78761","name":"Faculty\/Staff"},{"id":"78771","name":"Public"},{"id":"174045","name":"Graduate students"},{"id":"78751","name":"Undergraduate students"}],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[],"email":[],"slides":[],"orientation":[],"userdata":""}}}