WATCH: Building a rail underpass in 51 hours
By: John Bambridge
The first of four rail bridges being built to enable pedestrians to cross under a busy rail corridor in California has been built in 51 hours flat in an effort to minimise the disruption to train traffic.
The $5.9m bridge is a component of a broader $25.7m project to ease passage around the busy San Diego to Los Angeles rail corridor, which carries more than 50 passenger and freight trains a day.
The San Diego Association of Governments is project manager, with TY Lin as design engineer, Flatiron as general contractor and Caltrop responsible for construction management.
This time-lapse video shows the site as crews install the bridge - from excavation to the laying the tracks: