More than two years ago Montgomery County made public KCE's March 15, 2013 report that documents serious design and construction flaws with the SSTC. Metro's May 2, 2013 report followed. Both reports are on Montgomery County's website. Has anyone "at the top" of Montgomery County read these reports? or the report summaries?
The cause of the cracking, the complete lack of expansion/contraction joints in the 315 ft. wide by 580 ft. long SSTC, is in both reports. Both reports point out that Metro's design and construction standards require expansion/contraction joints be placed no farther apart than every 100 feet.
The question that neither report answers is how one retrofits expansion/contraction joints into a completed concrete building that has been designed and built with none. None of the many media reports over the past 2+ years addresses this either. Why?
From October 2013:
"A representative for the general contractor for the SSTC, Foulger-Pratt, was described in media reports as saying that the SSTC is “like a tightly wound snare drum”. The problem with the “snare drum” analogy is that a tightly wound snare drum can be loosened, while a large concrete building without expansion joints cannot."silver spring transit center: expansion joints, snare drum, slot test
From September 2014:
"One of the significant findings of KCE's report is that the SSTC doesn't have any expansion/contraction joints. Standard design and construction practice and WMATA design and construction standards require expansion/contraction joints in structures exposed to temperature changes. WMATA design and construction standards, to which the SSTC was supposed to have been designed and constructed, require expansion/contraction joints be spaced no more than 100 feet apart. The 315 ft. wide by 580 ft. long SSTC has none."
Not long after KCE's report was released, Bryant Foulger of Foulger Pratt, the SSTC's builder/contractor, said that "the SSTC is like a tightly wound snare drum".
When the SSTC tries to expand or contract because of changes in temperature, hot or cold respectively, it can't, because it has no expansion/contraction joints. The monolithic, post-tensioned, concrete SSTC is like a tightly wound snare drum, and it cracks. Without expansion/contraction joints, the SSTC will continue to crack even after it's "fixed" with its"repairs required to increase the combined shear and torsional capacity of certain beams and girders" and its concrete overlay.
Nice analogy, Mr. Foulger! The only problem is that you can loosen a tightly wound snare drum; but, you can't loosen a 315 ft. wide by 580 ft. long monolithic, post-tensioned, concrete structure that doesn't have any expansion/contraction joints. Without expansion/contraction joints, the SSTC will continue to crack, even after it's "repaired"silver spring transit center: Silver Spring Transit Center: what about the columns?
Are the private engineering, contracting and inspection companies at fault? Is Metro at fault? Is Montgomery County at fault? Are the Maryland Transit Administration and the Federal Transit Administration at fault? Or, are they all at fault?
Are the media, and the public, at fault for failing to ask the right questions? How many of the media reporting on this story for the past 2+ years, or the public who are paying for it, have read these reports (or the report summaries)?
After all of the delays, and public money spent, perhaps it's time for all involved to stop pointing the finger, posturing and evading the real questions.
An internet search of "parking garage expansion joints" yields many examples:
- http://www.emseal.com/Products/Architectural/Parking/ParkingDeckProductGuide.htm
- https://wbacorp.com/products/parking-sturctures-and-stadiums
- http://www.mmsystemscorp.com/ejp/
- etc.
Where are the Silver Spring Transit Center's expansion joints?
spinmeisters Leggett, Leventhal, Berliner, Dise, et al
Silver Spring Transit Center
Paul S. Sarbanes Transit Center
Montgomery County MD
public-private partnership
WMATA
Federal Transit Administration (FTA)
Maryland Transit Administration (MTA)
Purple Line
Gov. Hogan
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