This very thing occurred in PGH with the Greenfield Bridge[0]. This caused significant disruption because the bridge spans a major highway to the eastern subur

This very thing occurred in PGH with the Greenfield Bridge[0]. This caused significant disruption because the bridge spans a major highway to the eastern suburbs. Of course, the infrastructure issues with that bridge were rather obvious, since chunks of concrete would fall on to the highway (necessitating netting to be installed). [0] http://greenfieldbridge.otmapgh.org/ http://greenfieldbridge.otmapgh.org/