Please join us for our October Chapter Meeting for a presentation from Dr. Ali Abu-Yosef, PE, SE with Pivot Engineers

Topic Title:         Game of Miles and Inches

Presenter:          Ali Abu-Yosef, PhD, PE, SE

Topic Description: 

Less than 6 years after construction, a six-foot long piece of concrete fell more than 200 feet into the podium of a 58-story luxury high rise condominium.  The delaminated concrete exhibited rust staining and evidence of premature reinforcement corrosion. With more than 1.7 linear miles of exposed slab edges in the building, Pivot was retained to determine the probable cause of the corrosion damage and the extent of the problem. To this end Pivot conducted a comprehensive forensic investigation that evaluated a statistically representative and spatially distributed sample. Using non-destructive and destructive testing, Pivot determined that carbonation-induced corrosion due to improper placement of slab reinforcement during original construction was the primary cause of the observed corrosion damage. The investigation also determined that the construction deficiency was systemic and affected the majority of the 1.7 linear miles of exposed slab edges in the building.      

Based on the investigation findings, Pivot developed a repair scheme that includes full-depth removal and replacement of the affected slab edges. Because of dimensional restraints and congestion of existing slab edge reinforcement, the repair utilized glass fiber reinforced polymer (GFRP) reinforcing bars and dowels to support the repair concrete. The poster will present the forensic investigation findings and discuss the unique challenges associated with designing and implementing the slab-edge repairs.  

About Ali:

Ali is a structural engineer with a penchant for everything corroding and all that is oxidized. Whether chloride-contaminated parking garages or microbe-infested bridge piles, Ali's experience includes examination of the usual and unusual corrosion suspects. Since joining Pivot, he has performed forensic investigations of structural failures, evaluated service life of critical infrastructure, and designed state-of-the-art structural repairs.

At the University of Jordan, Ali received a B.S. in Civil and Environmental Engineering. He later obtained a M.S. and Ph.D. in Structural Engineering at The University of Texas at Austin, where his graduate research helped develop a novel class of low-cost wireless sensors that enable early detection of corrosion in reinforced concrete structures. In addition to publishing multiple technical peer-reviewed articles and conference proceedings, Ali is also an active member in a number of American Concrete Institute (ACI) and National Association of Corrosion Engineers (NACE) technical committees.