"a working group of independent engineering and construction experts" is what’s needed. So far, we’ve only heard from those involved in the project and paid for by Montgomery County. A truly independent group should examine the severe cracking in slabs, beams, girders and columns and other defects (slabs less than the 10 inches thick called for, exposed reinforcement, missing reinforcement, under-designed beams, etc.), determine what caused the defects, and then determine solutions that will address underlying causes.
Montgomery County’s report, made public more than a year ago, attributes the SSTC’s serious defects to errors and omissions by the SSTC’s contractor/builder, the engineer/designer and the concrete inspector/tester. The report notes that the SSTC doesn’t have expansion joints. Standard design and construction practice requires expansion joints in outdoor structures exposed to temperature changes. WMATA design and construction standards, to which the SSTC was supposed to have been designed and constructed, call for expansion joints to be located no more than 100 feet apart; the 315 ft. by 580 ft. SSTC has none. Could it be that the extensive cracking in the SSTC is caused by its total lack of expansion joints? If so, then the two inch latex concrete overlay planned for the SSTC will not fix the underlying problem (lack of expansion joints).
Since the Silver Spring Transit Center is an integral part of WMATA's regional system, serving DC, VA & MD, I would have preferred to see structural engineering and construction experts from DC (e.g., Howard University's College of Engineering, Architecture and Computer Sciences) and VA on Montgomery County's "working group of independent engineering and construction experts". Nonetheless, I look forward to the independent engineering and construction experts’ report. Hopefully, Montgomery County will hold public meetings so that we can finally learn what the County is doing in the way of repairs, and why, and we can ask our questions and provide our comments on the public record.
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