Investigators from the National Institute of Standards and Technology (NIST) say they have found no evidence of underground voids on the site of the Champlain Towers South collapse, according to a new NIST report.
The team of investigators have studied the site’s subsurface conditions to determine if sinkholes or excessive settling of the pile foundations might have caused the collapse. They have found no such evidence to support that potential cause.
Preliminary evaluation of data indicates about one quarter of an inch or less of settling in the pile foundations supporting the pool deck structure and basement. This would have had minimal impact on the pool deck structure, NIST says.
“Understanding exactly what caused this collapse is taking meticulous investigation and the collection of copious amounts of evidence and information,” said Joannie Chin, director of NIST’s Engineering Laboratory. “Our team members are dedicated to unraveling the complexities of this tragic event, and their rigorous research and analysis will not only help us understand the likely technical cause of the collapse but will improve the safety of our communities.”
The team’s preliminary evaluation of physical and historical evidence found that the pool deck construction deviated from design requirements. Specifically, the number of slab reinforcing bars centered over vertical columns was inadequate, and the reinforcing bars in the top of the slab in the vicinity of the columns were spaced farther apart than the design required, according to investigators. These deviations weakened the slab-column connections, they said.
NIST expects technical work on the investigation to be substantially completed in late June 2024 and aims to release a report with findings and recommendations in late June 2025.
Related Stories
| Sep 16, 2013
Does brainstorming work?
The idea-generating process known as brainstorming has come under some intense fire recently. Critics contend that it suspends much-needed criticism and conflict while suppressing the creative ideas of introverts.
| Sep 16, 2013
Passive solar, enhanced envelope crucial to Univ. of Illinois net-zero project
Passive solar strategies and an enhanced envelope are keys to achieving net-zero on the new 230,000 sf Department of Electrical and Computer Engineering building at the University of Illinois at Urbana-Champaign.
| Sep 16, 2013
Forty-three percent of energy leaders will invest more in efficiency next year (infographic)
Forty-three percent of energy leaders say their investment in energy efficiency next year is projected to be more than it was last year, according to survey results released today by Schneider Electric. Twenty-two percent said their projected investment would stay the same, and 10 percent reported their investment would be less than last year.
| Sep 16, 2013
Forty-three percent of energy leaders will invest more in efficiency next year (infographic)
Forty-three percent of energy leaders say their investment in energy efficiency next year is projected to be more than it was last year, according to survey results released today by Schneider Electric. Twenty-two percent said their projected investment would stay the same, and 10 percent reported their investment would be less than last year.
| Sep 16, 2013
Construction spending hits four-year high in July: AGC report
Total construction spending hit a four-year high in July as private residential and nonresidential activity increased while public spending declined, according to an analysis of new Census Bureau data by the Associated General Contractors of America. Association officials urged lawmakers in Washington to make infrastructure investment a top federal priority before funding runs out at the end of September.
Sponsored | | Sep 16, 2013
Channel glass welcomes Hollywood Casino visitors in style
Turning the site of an abandoned auto factory into a glamorous casino is no easy task. Pilkington Profilit™ low-iron, wave channel glass with a translucent metallic gold coating helped the design team for the Hollywood Casino in Columbus, Ohio, achieve this goal by capturing the golden age of Hollywood from the outside in.
| Sep 15, 2013
How to build a rainscreen using fiber cement panels - AIA/CEU course
This course will review the cause and effects of moisture intrusion and explain how fiber cement panels can be used as a rain screen to reduce moisture build-up, rotting interior walls, and mold growth.
| Sep 13, 2013
Loews Hotels & Resorts announces major cross-portfolio upgrades
Loews Hotels & Resorts is currently in the midst of a major growth and property redesign initiative, reflecting a strong national trend in hospitality renovation.
| Sep 13, 2013
Insurance expert: Managing green liability risk not so different from 'normal' risk mitigation
Worries about legal liability have long dogged the sustainable building movement, but insurance expert Karen Erger says sustainability lawsuits are caused by the same types of issues that have always prompted clients to sue AEC firms.
| Sep 13, 2013
Video: Arup offers tour of world's first algae-powered building
Dubbed BIQ house, the building features a bright green façade consisting of hollow glass panels filled with algae and water.
