The Massachusetts Bay Transportation Authority (MBTA) proposed a Core Tunnel Segment alignment alternative that would comprise construction activities and bus operations adjacent to the New England Medical Center (NEMC) Floating Hospital in Boston. The NEMC expressed concern over potential vibration effects from construction and eventual operation of the Silver Line utilizing the NEMC portal. Vibration-sensitive locations included MRI units in the MRI Suite, a mobile MRI Trailer, 3rd-floor clinical labs and 5th-floor operating rooms.
HMMH was retained to perform an assessment of potential vibration impacts at the vibration-sensitive locations within the NEMC. HMMH conducted vibration propagation measurements to determine the transfer of vibrations through the ground and into the building at the site of construction activities, and projected future vibration levels at each of the chosen locations.