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
| Jan 3, 2012
AIA's ABI November Index reaches 52.0
The Architecture Billings Index (ABI) reached its first positive mark since August.
| Jan 3, 2012
Callison acquires Barteluce Architects & Associates
This acquisition will grow Callison’s New York team to over 75 architects.
| Jan 3, 2012
VDK Architects merges with Harley Ellis Devereaux
Harley Ellis Devereaux will relocate the employees in its current Berkeley, Calif., office to the new Oakland office location effective January 3, 2012.
| Jan 3, 2012
Weingarten, Callan appointed to BD+C Editorial Board
Building Design+Construction has named two new members to its editorial board. Both are past recipients of BD+C’s “40 Under 40” honor.
| Jan 3, 2012
New Chicago hospital prepared for pandemic, CBR terror threat
At a cost of $654 million, the 14-story, 830,000-sf medical center, designed by a Perkins+Will team led by design principal Ralph Johnson, FAIA, LEED AP, is distinguished in its ability to handle disasters.
| Jan 3, 2012
BIM: not just for new buildings
Ohio State University Medical Center is converting 55 Medical Center buildings from AutoCAD to BIM to improve quality and speed of decision making related to facility use, renovations, maintenance, and more.
| Jan 3, 2012
New SJI Rule on Steel Joists
A new rule from the Steel Joist Institute clarifies when local reinforcement of joists is required for chord loads away from panel points. SJI members offer guidance about how and when to specify loads.
| Jan 3, 2012
AIA Course: New Developments in Concrete Construction
Earn 1.0 AIA/CES learning units by studying this article and successfully completing the online exam.
| Jan 3, 2012
The Value of Historic Paint Investigations
An expert conservator provides a three-step approach to determining a historic building’s “period of significance”—and how to restore its painted surfaces to the correct patterns and colors.
| Jan 3, 2012
28th Annual Reconstruction Awards: Bringing Hope to Cancer Patients
A gothic-style structure is reconstructed into comfortable, modern patient residence facility for the American Cancer Society.
