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
Multifamily Housing | Feb 21, 2023
New multifamily housing and mixed-use buildings in Portland, Ore., must be ready for electric vehicle charging
The Portland, Ore., City Council recently voted unanimously to require all new residential and mixed-use buildings to be ready for electric vehicle charging. The move amends Portland’s zoning laws to require all new multi-dwelling and mixed-use development of five or more units with onsite parking to provide electric vehicle charging infrastructure.
Steel Buildings | Feb 21, 2023
AISC releases SpeedCore design guide for building concrete-filled composite steel plate shear wall core systems
The American Institute of Steel Construction has released Design Guide 38, SpeedCore Systems for Steel Structures. The document pertains to the nonproprietary concrete-filled composite steel plate shear wall core system that “shaved a whopping 10 months off the erection schedule of Seattle’s 58-story Rainier Square,” according to AISC.
K-12 Schools | Feb 18, 2023
Atlanta suburb opens $85 million serpentine-shaped high school designed by Perkins&Will
In Ellenwood, Ga., a southeast suburb of Atlanta, Perkins and Will has partnered with Clayton County Public Schools and MEJA Construction to create a $85 million secondary school. Morrow High School, which opened in fall 2022, serves more than 2,200 students in Clayton County, a community with students from over 30 countries.
Museums | Feb 17, 2023
First Americans Museum uses design metaphors of natural elements to honor native worldview
First Americans Museum (FAM) in Oklahoma City honors the 39 tribes in Oklahoma today, reflecting their history through design metaphors of nature’s elements of earth, wind, water, and fire. The design concept includes multiple circles suggested by arcs, reflecting the native tradition of a circular worldview that encompasses the cycle of life, the seasons, and the rotation of the earth.
Senior Living Design | Feb 15, 2023
Passive House affordable senior housing project opens in Boston
Work on Phase Three C of The Anne M. Lynch Homes at Old Colony, a 55-apartment midrise building in Boston that stands out for its use of Passive House design principles, was recently completed. Designed by The Architectural Team (TAT), the four-story structure was informed throughout by Passive House principles and standards.
Multifamily Housing | Feb 10, 2023
Dallas to get a 19-story, 351-unit residential high-rise
In Dallas, work has begun on a new multifamily high-rise called The Oliver. The 19-story, 351-unit apartment building will be located within The Central, a 27-acre mixed-use development near the Knox/Henderson neighborhood north of downtown Dallas.
Sustainability | Feb 9, 2023
New guide for planning, designing, and operating onsite water reuse systems
The Pacific Institute, a global nonpartisan water think tank, has released guidance for developers to plan, design, and operate onsite water reuse systems. The Guide for Developing Onsite Water Systems to Support Regional Water Resilience advances circular, localized approaches to managing water that reduce a site’s water footprint, improve its resilience to water shortage or other disruptions, and provide benefits for local communities and regional water systems.
Office Buildings | Feb 9, 2023
Post-Covid Manhattan office market rebound gaining momentum
Office workers in Manhattan continue to return to their workplaces in sufficient numbers for many of their employers to maintain or expand their footprint in the city, according to a survey of more than 140 major Manhattan office employers conducted in January by The Partnership for New York City.
Giants 400 | Feb 9, 2023
New Giants 400 download: Get the complete at-a-glance 2022 Giants 400 rankings in Excel
See how your architecture, engineering, or construction firm stacks up against the nation's AEC Giants. For more than 45 years, the editors of Building Design+Construction have surveyed the largest AEC firms in the U.S./Canada to create the annual Giants 400 report. This year, a record 519 firms participated in the Giants 400 report. The final report includes 137 rankings across 25 building sectors and specialty categories.
University Buildings | Feb 8, 2023
STEM-focused Kettering University opens Stantec-designed Learning Commons
In Flint, Mich., Kettering University opened its new $63 million Learning Commons, designed by Stantec. The new facility will support collaboration, ideation, and digital technology for the STEM-focused higher learning institution.
