MBTA Aquarium Station Modernization (Central Artery C17B1)
Blue Line station modernization, incorporating 150-foot section of Central Artery directly above platform extension. New entrances, top-down construction.
The Aquarium Station modernization included extension of existing platforms to accommodate six-car trains, construction of a new west entrance, and reconstruction of the existing east entrance. The project scope included incorporation of a 150-foot-long section of the Central Artery Tunnel (CA/T). Use of the Central Artery viaduct during construction required installation of an underpinning system and demolition of the existing foundations. Service was maintained on the Blue Line, Central Artery, and surface roads throughout construction. The section of the CA/T constructed directly above the MBTA platform extensions used Soldier Pile Tremie Concrete (SPTC) walls and steel transfer girders to span the platforms. Work proceeded in phases, with the west mezzanine built first, using top-down construction. The east entrance was then demolished and replaced, using traditional "cut-and-cover" construction.
The site is a major intersection of surface roads and pedestrian routes. The historic State Street Block (SSB) building is adjacent to the 65-foot-deep excavation for the new west entrance. The use of top-down construction mitigated the effects of construction on vehicular and pedestrian traffic and on the SSB building. Impact of deep excavation on the SSB building was further reduced by the use of T-panels. The stem of the "T" was composed of a temporary steel truss, increasing wall stiffness. The project was designed to accommodate the future North-South Rail Link project, a railroad tunnel that will connect Boston's North and South Stations.
Completion Date: 2004 Location: Boston, Massachusetts Owner or Client: Massachusetts Bay Transportation Authority Prime Consultant(s): Ellenzweig Associates