Replacement of CR16 Horseblock Road Bridge Over LIRR
LiRo is providing engineering services to the Suffolk County Department of Public Works for the design of a replacement for the bridge that carries CR16, Horseblock Road, over the Long Island Railroad and Long Island Avenue. The existing bridge is a four-span, steel framed structure, with several deficiencies that must be addressed. The initial effort will determine if the project should entail replacement or rehabilitation of the bridge. The bridge's deficiencies include inadequate width; deficient load capacity; substandard vertical alignment, resulting in inadequate sight distance; seismic vulnerability; and non-redundant structural elements. Since these problems cannot be easily corrected by bridge rehabilitation, replacement will most likely be required.
The major project decisions included in the design of a replacement bridge will include the development of a new layout, determination of the ideal bridge structure type, maintenance and protection of traffic, and coordination with the LIRR. The existing bridge's roadway network capacity for traffic to be detoured during construction will be evaluated and coordinated with both the relevant agencies and the local community. If a detour cannot be executed, a design will be developed to allow for the staged construction of the new bridge, with traffic initially maintained on a portion of the existing bridge, and subsequently on a combination of the new and the existing structure. The design will also address the staged demolition of the existing bridge, and the requirements for temporary supports. All work will be performed in accordance with AASHTO and NYSDOT guidelines.
LiRo services include development and evaluation of alternatives; preparation of design reports (Phases I-VI); survey of existing conditions; final design (Phases V-VI) of the replacement bridge; and associated approach highway reconstruction including maintenance and protection of traffic.