Technical details
Chicago Transit Authority
Chicago, IL
Detailed guideway design, Engineer of Record for segmental structure, traction power and grounding design, stray current management.

The RPM Program is the largest capital program undertaken by the CTA. The corridor was built nearly 100 years ago and much of its infrastructure is at the end of its useful life and recurrent maintenance is costly and causes service delays. As part of the design-build team, SYSTRA is designing the elevated guideway, systemwide grounding system, and stray current/corrosion management and isolation scheme across electrical, traction power, signal, and communications for four new stations and six relay rooms over four tracks.

Due to the unique character of the proposed structure within the Chicago system, SYSTRA to developed a unique stray current protection system that effectively protects both the new closed-deck segmental structure and the adjacent open-deck steel structures.

The complex elevated guideway consists of multiple structure types that are interconnected. SYSTRA developed a segmental concrete guideway design for a major portion of the project. This design required approval of an alternate technical concept that significantly improved upon the baseline steel design. It will be the first segmental structure built by the CTA.

This program will expand capacity on the CTA’s most used lines to accommodate CTA’s current and future ridership. This large, multi-stage project is being completed in phases, allowing for the greatest number of improvements while minimizing impacts to riders and the surrounding communities.