Title: Parcel 6 Development, Central Artery/Tunnel Project, Boston, Massachusetts

Author(s): B. S. Moffat and E. P. White

Publication: Symposium Paper

Volume: 209

Issue:

Appears on pages(s): 109-132

Keywords: boat section ramp; deveIopment parceI; lateral analysis; lid structure; seismic load; wind load

DOI: 10.14359/12497

Date: 9/26/2002

Abstract:
Completion of the Central A r t e r y b e l Project inchdes development of more that 20 distinct parcels along the original, elevated artery corridor. This paper presents challenges encountered during the design of Parcel 6, which is located between New Chardon and Sudbury Streets in Boston, Massachusetts. The Parcel 6 lid will cover five adjacent cast-in-place concrete boat section ramps. The final use of the lid is not yet known; however, since construction of the ramps is currently underway, the walls were re-designed to accommodate either a landscaped deck, or a five-story building. Design included both wind and seismic lateral analyses of the two types of potential lid structures, with the reinforcing in the ramp walls modified to accommodate both options in order to minimize impacts or retrofits requkd in the future. Changes to the original design included modifying wall heights and reinforcing, and inclusion of interim backwalls for temporary earth support. The landscaped option included preliminary designs of four separate deck structures, skewed portal beams, overhead impact attenuators, and a merge gore area. The building option presumed asymmetrical column loadings and locations, with a comparative analysis of column base shears used to determine maximum loading on the existing ramp walls.