Type: Tower Drive Vertical Lift
Location: Placentia, NL
Owner: Newfoundland Labrador Transportation and Works
Stafford Bandlow Engineering personnel provided mechanical and electrical engineering services for this new tower drive vertical lift bridge from inception through completion. Services included development of a Bridge Design Report and preparation of plans, specifications and cost estimates for the design of all machinery and construction services.
The design features two mechanically independent tower drive systems. Rolling element main counterweight sheave bearings were selected to minimize friction and maintain a compact machinery package that would fit in the available space.
The mechanical design includes all span support machinery (counterweight sheaves and bearings, counterweight ropes and terminations and live load supports), span drive machinery (motors, brakes, couplings shafts, speed reducers, operating ropes and deflector sheaves) and span locks (motors, speed reducers, lock bars, guides and receivers). The objective of the mechanical design was to integrate the mechanical systems into the structure with minimal impact from a visual perspective while minimizing maintenance requirements and improving overall system efficiency.
The electrical scope of the project includes complete replacement of the bridge electric utility service, new standby generator service, and control system including all field feedback devices and traffic gates. Control system technology will utilize a Programmable Logic Controller for system control and monitoring including capability for remote monitoring and diagnostics. The span drive system will utilize digitally controlled variable speed motor drives.