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
Giants 400 | Nov 28, 2022
Top 85 Office Sector Engineering and EA Firms for 2022
Jacobs, Alfa Tech, AECOM, and Burns & McDonnell head the ranking of the nation's largest office sector engineering and engineering/architecture (EA) firms for 2022, as reported in Building Design+Construction's 2022 Giants 400 Report.
Legislation | Nov 23, 2022
7 ways the Inflation Reduction Act will impact the building sector
HOK’s Anica Landreneau and Stephanie Miller and Smart Surfaces Coalition’s Greg Kats reveal multiple ways the IRA will benefit the built environment.
Multifamily Housing | Nov 22, 2022
10 compelling multifamily developments debut in 2022
A smart home tech-focused apartment complex in North Phoenix, Ariz., and a factory conversion to lofts in St. Louis highlight the notable multifamily developments to debut recently.
Digital Twin | Nov 21, 2022
An inside look at the airport industry's plan to develop a digital twin guidebook
Zoë Fisher, AIA explores how design strategies are changing the way we deliver and design projects in the post-pandemic world.
Industrial Facilities | Nov 16, 2022
Industrial building sector construction, while healthy, might also be flattening
For all the hoopla about the ecommerce boom and “last mile” order fulfillment driving demand for more warehouse and manufacturing space, construction of industrial buildings actually declined over the past five years, albeit marginally by 2.1% to $27.3 billion in 2022, according to estimates by IBIS World. Still, construction in this sector remains buzzy.
Seismic Design | Nov 16, 2022
SPC-4D: 7 reasons California hospital building owners should act now to meet seismic compliance
Seismic compliance with the applicable California building codes is onerous and disruptive for building owners, especially for a building in the heavily regulated sector of healthcare. Owners of older buildings that house acute care services have a big deadline on the horizon—Jan. 1, 2030, the cutoff date to upgrade their buildings to SPC-4D.
Wood | Nov 16, 2022
5 steps to using mass timber in multifamily housing
A design-assist approach can provide the most effective delivery method for multifamily housing projects using mass timber as the primary building element.
Giants 400 | Nov 14, 2022
Top 65 Airport Terminal Engineering + EA Firms for 2022
AECOM, Jacobs, Arup, and Burns & McDonnell head the ranking of the nation's largest airport terminal engineering and engineering/architecture (EA) firms for 2022, as reported in Building Design+Construction's 2022 Giants 400 Report.
Giants 400 | Nov 14, 2022
4 emerging trends from BD+C's 2022 Giants 400 Report
Regenerative design, cognitive health, and jobsite robotics highlight the top trends from the 519 design and construction firms that participated in BD+C's 2022 Giants 400 Report.
Green | Nov 13, 2022
NREL report: Using photovoltaic modules with longer lifetimes is a better option than recycling
A new report from the U.S. National Renewable Energy Laboratory (NREL) says PV module lifetime extensions should be prioritized over closed-loop recycling to reduce demand for new materials.
