Gilbert Hegemier

Last updated
Gilbert Arthur Hegemier
ASME Fellow
JPG-Gil-Hegemier-24 -.jpg
Hegemier in 2024
NationalityAmerican
Alma mater California Institute of Technology (Ph.D., M.S.)
Known forRetrofitting techniques for earthquake safety, and the use of fiber-reinforced composites in construction
Awards
  • The Revelle Medal (2022) [1] [2] [3]
  • CERF Charles Pankow Award for Innovation (1996)
  • UCSD's Chancellor's Associates Shiley Achievement Award (1994) [4]
Scientific career
Fields Structural engineering, earthquake engineering
Institutions University of California, San Diego
Thesis Stability of Thin Cylindrical Shells Subjected to a Class of Axially Symmetric Moving Loads  (1964)
Doctoral advisor Ernest Edwin Sechler
Other academic advisorsJames. K. Knowles
Years active1964-present
TitleDistinguished Professor Emeritus

Gilbert Arthur Hegemier is an American engineer and academic known for his work in structural and aerospace engineering, as well as applied physics. He is a Distinguished Professor Emeritus at the Jacobs School of Engineering at the University of California, San Diego (UCSD), and is recognized as one of the founding faculty members of the institution. [5] Hegemier's research has focused on enhancing public safety through the development of retrofitting techniques for structures in earthquake-prone areas, as well as on protective technologies against blast and ballistic threats. His contributions have been acknowledged by his involvement with professional organizations such as the American Institute of Aeronautics and Astronautics, the Earthquake Engineering Research Institute, and the American Society of Mechanical Engineers, where he has been a fellow since 1997.

Contents

Biography

Hegemier earned his M.S. and Ph.D. in Solid Mechanics and Structures from the California Institute of Technology. Early in his career, he worked as a mechanical engineer at several organizations, including TRW Systems Space Technology Lab, the National Engineering Science Company, and the Naval Ordnance Laboratory. His professional focus shifted toward earthquake safety following the 1971 San Fernando Valley and 1972 Nicaragua earthquakes. [6] At UCSD, Hegemier led a team that developed and tested full-scale bridge column retrofit systems. These systems were notably effective during the 1994 Los Angeles earthquake, helping to minimize damage to retrofitted bridges. [7] [8] [9] His research also includes work on using lightweight fiber-reinforced composites for infrastructure repair and developing methods for blast mitigation to protect critical structures. Hegemier has received various awards for his contributions, including the 2022 Revelle Medal. [1] [2] He has been a fellow of the American Society of Mechanical Engineers since 1997 and is a member of the Earthquake Engineering Research Institute. In 1995, he was elected to the Golden Key International Honour Society. [10]

In 1975, Hegemier achieved tenure as a Full Professor at UCSD, [11] and in 2010, he was recognized with the title of Distinguished Professor. In 1986, [12] [13] he was instrumental in founding the Charles Lee Powell Structural Systems Laboratories at UCSD, where he served as the first Director. This facility supports full-scale experimental testing of various structural systems, including buildings up to five stories and large bridge segments. The laboratory was developed to enhance the Structural Engineering Program at UCSD, facilitate international research collaborations, and strengthen connections between academia and industry. Additionally, Hegemier and his colleagues expanded the lab's capabilities with a field station focused on explosive loading and an outdoor shake table, which is notable for being the world's largest and has been used for seismic tests on full-scale structures up to ten stories. [14]

In 1998, the Department of Structural Engineering (SE) was established at UCSD, with Hegemier playing a key role in its creation. He later served as the department's chair from 2007 to 2012. Unlike typical civil engineering departments in the United States, SE at UCSD has a broader focus on structures, encompassing not only civil engineering but also aerospace and marine structures. [15] [16]

Hegemier has conducted significant research on protective technologies for civil structures, with a focus on engineering solutions for blast and seismic protection. His work includes the development of advanced fiber-reinforced composites, which have been used in retrofitting buildings to withstand both blast and seismic events. [17] The effectiveness of these technologies was tested in full-scale experiments, including blast testing at White Sands Missile Range and seismic testing at UCSD Powell Laboratories.

Between 2003 and 2010, Hegemier directed a significant blast mitigation program in the United States, focusing on enhancing the safety and resilience of critical infrastructure. Funded by the Technical Support Working Group (TSWG) under the Combatting Terrorism Technical Support Office (CTTSO), this program involved extensive laboratory and field testing, along with advanced computational analysis. The aim was to develop protective technologies for essential structures, including buildings, bridges, tunnels, pipelines, and other critical systems.

Hegemier has contributed his expertise in blast damage mitigation to a variety of governmental and private organizations. [6] His work has involved collaboration with entities such as the Technical Support Working Group (TSWG), the Department of Homeland Security's Transportation Security Administration, and the Port Authority of New York and New Jersey. Additionally, he has been involved in projects with national laboratories, including Lawrence Livermore and Sandia, as well as with companies like Science Applications International Corporation (SAIC), Parsons Brinkerhoff, Protective Technologies LLC, and Karagozian & Case. His experience also extends to participation in forensic investigations related to blast and seismic events. [18]

Hegemier's research has received funding from various government agencies, including the Defense Advanced Research Projects Agency (DARPA), the Defense Threat Reduction Agency (DTRA), the Federal Highway Administration (FHWA), the California Department of Transportation (Caltrans), and the National Science Foundation (NSF). Additional support has come from the Air Force Office of Scientific Research (AFSOR), the Office of Naval Research (ONR), and national laboratories such as Los Alamos National Laboratory (LANL) and Lawrence Livermore National Laboratory (LLNL). [19]

Hegemier played a significant role in transferring technology to industry by founding Composite Solutions, Inc., where he served as chairman for several years. The company was involved in multiple projects utilizing advanced Carbon Fiber Reinforced Polymer (CFRP) composites for civil structural retrofits and repairs. One notable project was the reinforcement of the Cheonggyecheon restoration project in South Korea, which involved the use of 14 miles (22.5 km) of CFRP strips to strengthen 5.5 km of a viaduct. [20]

In 2024, Hegemier was honored by the UCSD by creating an endowed Chair in his name. [21] In December the same year, he was named a Top Educator by Marquis Who's Who. [22]

Selected publications

Earthquake Engineering

Protective Technologies for Blast Loading of Structures

Use of Fiber-reinforced Polymer Composites in the Design of Civil Structures

Modeling of Reinforced Concrete

Bridge Engineering

Composite Materials

Geophysics

Aerospace Structures

Awards and honors

Related Research Articles

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References

  1. 1 2 3 UC San Diego (2022-11-18). 2022 Revelle Medalist: Gilbert Hegemier . Retrieved 2024-06-25– via YouTube.
  2. 1 2 3 "UC San Diego Structural Engineering Gilbert (Gil) Hegemier Awarded Revelle Medal". jacobsschool.ucsd.edu. Retrieved 2024-06-25.
  3. 1 2 "The Revelle Medal". chancellor.ucsd.edu. Retrieved 2024-08-24.
  4. 1 2 "UCSD's seismic design experts Gilbert Hegemier, M.J. Nigel Priestly and Frieder Seible are named to receive Chancellor's Associates awards" (PDF). February 3, 1994.
  5. ↑ Johnson, Greg (1989-10-26). "UCSD Researchers Sift Through Nimitz Data : Earthquake: The team that rushed to the site of the Oakland collapse will use the information to help avert similar tragedies". Los Angeles Times. Retrieved 2024-08-22.
  6. 1 2 "Earthquake: Fears grow over structural safety of Californian freeways". New Scientist. 'The situation is both new and serious,' Gilbert Hegemier, director of structural systems laboratory at the University of California at San Diego, told New Scientist this week. 'We will not know how serious until the inspections of bridges and freeways are made and design tests are carried out in research laboratories.
  7. ↑ US6237292B1,Hegemier, Gilbert A.&Seible, Frieder,"Reinforcement of cementitious walls to resist seismic forces",issued 2001-05-29
  8. ↑ JP2007247401A,Seible, Freider; セイブル、, フライダー& Hegemier, Gilbert A.et al.,"弾性繊維補強複合構造部材",issued 2007-09-27
  9. ↑ US20150322686A1,HARPER, Jordan; Williams, Brian& WADE, Carl Allenet al.,"Blast resistant structure",issued 2015-11-12
  10. ↑ https://www.asme.org/getmedia/fb403911-4485-4a50-8232-3b04ea4ac4c0/Fellows-All-Updated-March-2024.pdf
  11. ↑ Stix, Gary (1993). "Concrete Solutions". Scientific American. 268 (4): 102–112. ISSN   0036-8733. JSTOR   24941446. Gilbert A. Hegemier, a U.C.S.D. professor of applied mechanics, said the approximately $50 million needed to build the bridge would also test concepts that could be exploited in the repair of existing structures and in the development of manufacturing techniques to make Lego-like construction a reality. "The hand-assembly methods for making composites for Stealth aircraft need to be automated," Hegemier says.
  12. ↑ "Three-Story Structure Slammed in Magnitude 8 Earthquake on Shake Table". phys.org. "This is a landmark test that will enable a very fast and economically advantageous high technology construction method to be used in seismically active regions of the United States," said Gilbert A. Hegemier, director of UC San Diego's Powell Structural Research Laboratories, and professor and chair of the Jacobs School of Engineering's Department of Structural Engineering.
  13. ↑ "Structural Systems Laboratory | Structural Engineering". structures.ucsd.edu. Retrieved 2024-08-22.
  14. ↑ "Faculty Profiles | Jacobs School of Engineering". jacobsschool.ucsd.edu. Retrieved 2024-08-22.
  15. ↑ "UC San Diego Structural Engineering Gilbert (Gil) Hegemier Awarded Revelle Medal". jacobsschool.ucsd.edu. Retrieved 2024-08-22.
  16. ↑ "Faculty | Structural Engineering". se.ucsd.edu. Retrieved 2024-08-22.
  17. ↑ https://apps.dtic.mil/sti/tr/pdf/ADA397336.pdf
  18. ↑ Hegemier, Gilbert; Seible, Frieder. "Equipment Request for the UCSD Structural Systems Laboratory".
  19. ↑ "NSF Award Search: Award # 8520685 - Equipment Request for the UCSD Structural Systems Laboratory". www.nsf.gov. Retrieved 2024-06-25.
  20. ↑ "Gilbert A Hegemier, Composite Solutions Inc Profile and Biography". www.bloomberg.com.
  21. ↑ "18 New Endowed Chairs Created at the UC San Diego Jacobs School of Engineering". today.ucsd.edu. Retrieved 2024-08-22.
  22. 1 2 "Gilbert Arthur Hegemier, PhD". Top Educators. 2024-12-17. Retrieved 2025-02-03.

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