Dr. Joseph A. Main is a research structural engineer in the Structures Group of the Materials and Structural Systems Division (MSSD) of the Engineering Laboratory (EL) at the National Institute of Standards and Technology (NIST). Dr. Main joined the Structures Group of the Materials and Construction Research Division in January 2005 as a National Research Council Postdoctoral Research Associate. Dr. Main's primary research interests relate to the computational assessment of structural performance under extreme loads, including modeling the response of structural systems beyond local failure to global collapse. Within this broad area, he has investigated structural response to wind loading, air-blast loading, and fire-induced heating.
After completing his Ph.D. in Civil Engineering at The Johns Hopkins University in 2002, Dr. Main held research appointments in the Department of Civil and Environmental Engineering at the University of Illinois at Urbana-Champaign and in the Weapons and Materials Research Directorate of the US Army Research Laboratory at Aberdeen Proving Ground. He was a visiting researcher in the Department of Mechanical Engineering at the Technical University of Denmark in the fall of 2003.
Dr. Main's doctoral research at The Johns Hopkins University involved long-term field measurement programs on three cable-stayed bridges to examine the problem of wind-induced stay cable vibrations and the mitigation of these vibrations using supplemental dampers. He developed analytical solutions for the complex vibration modes of taut cables, tensioned beams, and discrete systems with supplemental dampers, obtaining a universal form of approximation for the modal damping ratios that facilitates optimal damper placement and tuning. At the Army Research Laboratory, Dr. Main worked on computational modeling of the response of composite plates to air blast loading and investigated the role of shock wave propagation in the core of cellular metal sandwich plates in mitigating—or potentially enhancing—the incident blast pressure.
Dr. Main's postdoctoral research at NIST focused on development and implementation of methodologies to automate the handling of large aerodynamic and climatological databases within a reliability-based framework for structural analysis, to enable more accurate estimation of wind effects on structures. These results have been implemented in a publicly available software package, called windPRESSURE. Dr. Main's current research focuses on the development of computational modeling approaches aimed at analyzing the nonlinear behavior of structures undergoing collapse and assessing the vulnerability of structures to collapses that are disproportionate to the initiating event.