METROLINK LIGHT RAIL SYSTEM
St. Louis, Missouri
In 1992 and 1993 Reitz & Jens was retained by McCarthy, the general contractor, during construction of the Metrolink Rail System in downtown St. Louis, Missouri. As McCarthy’s construction engineer, Reitz & Jens designed nine separate temporary earth retention systems. Variations in subsurface conditions required several approaches to shoring at each retention system location. Two systems were designed to shore 26- feet deep excavations adjacent to streets, and multi-story structures. Another 15-foot deep system used cantilevered soldier pile.
As construction engineer, Reitz & Jens also evaluated the structural stability of the masonry walls to the 100 year old Eads Bridge. Analysis determined that a shoring system, using cantilevered H-pile was required to support the 35-foot high freestanding masonry walls during construction.
Reitz & Jens also designed, installed, and operated a system to continuously monitor and evaluate movements in shoring systems and adjacent buildings at four different stations excavated up to 30 feet below street level in downtown St. Louis. The age of these structures ranged from new construction to more than 100 years. The monitoring system included continuously monitored tiltmeters, inclinometers, and three-dimensional settlement points. The monitoring system was effective in early detection of several minor movements, which allowed the contractor to take corrective actions before any permanent damage occurred.
In 1997 and 2000 Reitz & Jens was retained directly by the Bi-State Development Agency to analyze and design improvements to mitigate two drainage induced landslides along the rail embankment. Reitz & Jens also observed and directed construction of the mitigation efforts. The corrective actions chosen involved a tied-back sheet pile wall and excavated rock wedge repair with associated drainage improvements. Inclinometers were also installed with the wall to monitor the long-term performance. The corrective actions were implemented without disrupting the Metrolink service.
In 2003 McCarthy retained Reitz & Jens as their Quality Control Engineer during construction of the Facilities 2 section of the Cross-County Metrolink expansion through the City of Clayton. The reach included construction of 2 underground stations and over 1 mile of cut and cover tunnel up to 40 feet below existing grades. The services provided by Reitz & Jens on this project included construction engineering, and responsibility for all quality control inspection and testing on this $100 million project.