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Title: Fracture Mechanics–Based Fragility Assessment of Pre-Northridge Welded Column Splices
A framework to assess the fracture fragility of partial joint penetration (PJP) welded column splices in steel moment frames constructed before the 1994 Northridge earthquake is presented. These pre-Northridge splices feature low flange penetration of the PJP welds, and low-toughness weld materials, such that they are considered susceptible to fracture with possible catastrophic consequences. Estimating their fracture risk is especially important, given that retrofitting them is highly disruptive to building operations. The presented framework addresses shortcomings of previous research and performance assessment guidance that does not consider key mechanistic or statistical effects. To accomplish this, three-dimensional fracture mechanics finite-element simulations are conducted to assess fracture toughness demands. These demands are then interpreted through a master curve–based approach that rigorously considers spatial randomness and weakest-link sampling of weld toughness properties, along with the uncertainty in estimation of these properties. The framework is implemented in a tool which automates the entire process, facilitating application in a professional setting. The tool (and the underlying framework) is demonstrated on a range of splice configurations to examine the effects of configuration, loading, and material parameters. Limitations are outlined.  more » « less
Award ID(s):
2129445
PAR ID:
10471541
Author(s) / Creator(s):
;
Publisher / Repository:
American Society of Civil Engineers
Date Published:
Journal Name:
Journal of Structural Engineering
Volume:
149
Issue:
6
ISSN:
0733-9445
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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