Final tunnel liner at the Mill Creek 3 project.

The article describes the cast-in-place tunnel lining for Phase 3 of the Mill Creek Tunnel (MCT3) in Ohio. It is one of the biggest tunneling projects headed by the Northeast Ohio Regional Sewer District (NEORSD). Final lining design for the Mill Creek tunnel was chosen based on the requirement for permanent tunnel support, ground water control and hydraulics. The contractor for the project decided to utilize collapsible steel forms to install the final concrete liner. Information on tunnel lining production rates, installation procedures and form buoyancies experienced during concrete placement are presented.