Metra Electric District 79th, 87th, 95th, 103rd, and 111th Street Stations
Date of Performance:
Cook County, IL
Structural Engineering Design Services
Dollar Value of Project:
The scope of work for this project is to design five new stations along the existing Metra Electric District (MED) line, and to rehabilitate the existing bridge structures for those five stations. The jurisdiction of stations along the MED line’s scope includes the stations located at 79th Street, 87th Street, 95th Street, 103rd Street, and 111th Street.
Garza Karhoff Engineering (GKE)is providing structural engineering services for the design of new station facilities ofthe111thStreet (Pullman) Station on the Metra Electric District line. GKE is also providing structural services for the rehabilitation of the bridge substructure for all stations along the MED line within the jurisdiction of the project scope. For the Pullman Station design, key tasks at street entrance level include evaluating the removal of a column and deck slab to shift the new stairway rising from grade to stationhouse, evaluating and designing a new elevator shaft, and providing locations required for temporary shoring. Entrance level station design also includes support footings and cantilever roof framing. At platform level, key design tasks include extending and upgrading the platform, addition of a new canopy for the entire length, substructure design for platform and elevator shaft, as well as framing and support of platform and roof level of the new headhouse. An exit stair for emergency use is also being provided at the end of the platform.
For the bridge rehabilitation at all of the project’s stations, the substructure repairs include a visual on-site inspection of the existing conditions of each bridge, encompassing existing structures adjacent to each station entrance, namely the two pier lines of columns, the abutment wall face, and overhead concrete slabs (underside of the bridge deck). The condition of the assessed areas has then been documented to map out the proposed repair plan for substructure rehabilitation. In addition, the rehabilitation also involves waterproofing the existing deck above the top face of the slabs along the length of the sidewalk span.