ABSTRACT
Construction of Kalbadevi Underground Metro Station of Mumbai Metro line 3 is an engineering challenge on one hand and a potboiler mix of social complications on the other. The under-construction station is in the midst of dilapidated buildings on congested lanes. The construction site was home of residential and commercial buildings, a fish market and an old bazar. 12 structures were demolished for a later in-situ rehabilitation. All the Project Affected Persons would be resettled in the area back to preserve their livelihood and social connect under a unique scheme. The project faced challenges of land acquisition, rehabilitation of PAP’s and litigations in superior courts for likely construction induced impacts on the structural integrity of a 160-year old heritage structure of high religious importance of a minority community. On engineering front, the station has two rectangular portions being constructed by cut & cover method to accommodate vertical circulation. Two platforms on UP & DN line tracks and a central horizontal circulation is created in caverns done by Conventional Excavation. Because of the topographical and logistical limitations, the alignment tunnels between adjoining stations for both UP & DN tracks were done by TBM’s and subsequently the lined tunnel widened by Conventional Excavation to create caverns to house the platforms and services. There were 131 structures in the Zone of Influence of the station box. Innovations were done in Blasting Design, to limit blast induced ground vibrations from propagating to the surrounding structures. Critical structures were supported and repaired. Real-time monitoring was put in place. The station is now 61% complete. The paper would discuss in detail as to how these issues of both social and technical nature were successfully dealt to execute this station in a complicated urban setting.
