It's no surprise that the SSTC continues to crack. Two years ago when WMATA's engineers appeared before Montgomery County's council, WMATA's engineers told the council that the SSTC was going to be a maintenance and operations headache for decades. Roger Berliner accused WMATA of being disingenuous, reneging on their agreement, just as MoCo is doing now.
It's all in the executive summary of the May 2, 2013 report that WMATA commissioned, that's on MoCo's website. It says: "The evaluation indicated that significant design and construction deficiencies have resulted in a structure that will be unable to achieve the 50 year design service life specified in WMATA design requirements without significant repairs and a long-term maintenance program to address durability problems.
The evaluation indicated that the overall design of the SSTC was deficient due to the restrained nature of the structure and the inability of the structure to accommodate normal thermal movements. The restrained nature of the as-designed structure was a significant factor in the observed cracking at the structure." (NOTE: None of the "repairs" made to the SSTC during the past two years addresses this deficiency. The SSTC remains restrained and unable to accommodate normal thermal movements. Also, "repairs" made to date to the unopened SSTC do not address cracks in columns and girders.)
The 315 ft. wide by 580 ft. long Silver Spring Transit Center doesn't have any expansion/ contraction joints, despite the fact that WMATA design and construction standards call for an expansion/contraction joint to be located no more than every 100 feet apart.
"Significant construction deficiencies were also observed in the evaluation. The construction deficiencies include omission of post-tensioning tendons in the pour strips on Level 330, thin concrete slabs, extensive cracking on the elevated slab surfaces as a result of restrained shrinkage and finishing problems, exposed and low concrete cover to post-tensioning ducts at numerous locations, and low entrained air content in the top surface of elevated slabs.
The life cycle costs for repair and maintenance of the SSTC structure will be significantly increased as a result of the design and construction defects."
politicians Leggett, Leventhal, Berliner, Dise, et al
SURPRISE!
Silver Spring Transit Center
Paul S. Sarbanes Transit Center
Montgomery County MD
WMATA
Federal Transit Administration (FTA)
Maryland Transit Administration (MTA)
public-private partnership
Purple Line
Gov. Hogan
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