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
| Aug 11, 2010
Nurturing the Community
The best seat in the house at the new Seahawks Stadium in Seattle isn't on the 50-yard line. It's in the southeast corner, at the very top of the upper bowl. "From there you have a corner-to-corner view of the field and an inspiring grasp of the surrounding city," says Kelly Kerns, project leader with architect/engineer Ellerbe Becket, Kansas City, Mo.
| Aug 11, 2010
AIA Course: Historic Masonry — Restoration and Renovation
Historic restoration and preservation efforts are accelerating throughout the U.S., thanks in part to available tax credits, awards programs, and green building trends. While these projects entail many different building components and systems, façade restoration—as the public face of these older structures—is a key focus. Earn 1.0 AIA learning unit by taking this free course from Building Design+Construction.
| Aug 11, 2010
BIM adoption tops 80% among the nation's largest AEC firms, according to BD+C's Giants 300 survey
The nation's largest architecture, engineering, and construction companies are on the BIM bandwagon in a big way, according to Building Design+Construction's premier Top 50 BIM Adopters ranking, published as part of the 2009 Giants 300 survey. Of the 320 AEC firms that participated in Giants survey, 83% report having at least one BIM seat license in house, half have more than 30 seats, and near...
| Aug 11, 2010
Integrated Project Delivery builds a brave, new BIM world
Three-dimensional information, such as that provided by building information modeling, allows all members of the Building Team to visualize the many components of a project and how they work together. BIM and other 3D tools convey the idea and intent of the designer to the entire Building Team and lay the groundwork for integrated project delivery.
| Aug 11, 2010
Great Solutions: Healthcare
11. Operating Room-Integrated MRI will Help Neurosurgeons Get it Right the First Time A major limitation of traditional brain cancer surgery is the lack of scanning capability in the operating room. Neurosurgeons do their best to visually identify and remove the cancerous tissue, but only an MRI scan will confirm if the operation was a complete success or not.
| Aug 11, 2010
Great Solutions: Collaboration
9. HOK Takes Videoconferencing to A New Level with its Advanced Collaboration Rooms To help foster collaboration among its 2,212 employees while cutting travel time, expenses, and carbon emissions traveling between its 24 office locations, HOK is fitting out its major offices with prototype videoconferencing rooms that are like no other in the U.
| Aug 11, 2010
2009 Judging Panel
A Matthew H. Johnson, PE Associate Principal Simpson Gumpertz & HegerWaltham, Mass. B K. Nam Shiu, SE, PEVP Walker Restoration Consultants Elgin, Ill. C David P. Callan, PE, CEM, LEED APSVPEnvironmental Systems DesignChicago D Ken Osmun, PA, DBIA, LEED AP Group President, ConstructionWight & Company Darien, Ill.
| Aug 11, 2010
Inspiring Offices: Office Design That Drives Creativity
Office design has always been linked to productivity—how many workers can be reasonably squeezed into a given space—but why isn’t it more frequently linked to creativity? “In general, I don’t think enough people link the design of space to business outcome,” says Janice Linster, partner with the Minneapolis design firm Studio Hive.
