Concrete Concerns Impact DIA Great Hall Construction
DENVER (CBS4)- A CBS4 Investigation has found that concerns about concrete strength in Denver International Airport's terminal are slowing the massive 3 year terminal renovation project. The project includes moving TSA checkpoints and ticket counters to the sixth floor of the Jeppesen Terminal.
Responding to an inquiry from CBS4, DIA's Vice President of Communications, Stacey Stegman, said limited concrete testing in DIA's terminal showed "the concrete compressive strength in certain sections of the Terminal was lower than what was specified in the Airport's historic documents/plans. Construction, due to the concrete testing, has slowed a bit in order to allow for additional tests and the time needed to better understand existing conditions."
The Great Hall project, which began last summer, calls for renovating about 1.5 million square feet of the terminal to enhance security, add new restaurants and shopping and "improve the overall passenger experience at DEN."
"Experts in the field of structural engineering have informed us that the airport is safe and can support the construction," said Stegman.
She said more test results and analysis is due in April and more will be known then about any adjustments that might need to be made or impact on current construction schedules.
"As an example, do we need to use a different type of crane?" wrote Stegman.
Tests on the 25-year-old concrete have also shown properties in the material that under certain conditions, could lead to an alkali silica reaction issue, or ASR, which is also known as "concrete cancer." Stegman said current samples show no indication of an ASR issue, but that "aggregate in the sample which has properties that, under certain environmental circumstances, could lead to an… (ASR) issue."
ASR can lead to concrete swelling and cracking.
In 2007, according to a Denver Post article, one DIA runway was temporarily closed and sections replaced when the concrete was found to have deteriorated and cracked due to ASR.
One source familiar with the concrete testing told CBS4 in coming months, concrete testing will expand to other areas of the airport.
