Railroad Routine Bridge Inspection

The past few weeks I've been busy working long nights for bridge and tunnel inspections. Our inspections were located in Revere, South Boston and Brookline and each had its own unique access requirements.

The Revere bridge spans over the Blue Line and was inspected using ladders since it was a short span consisting of prestressed concrete butted box beams in good condition. Using ladders allowed us more time for inspection since we did not have to wait for a hi-rail lift truck to be put on and driven to the bridge. We were able to get on track around 1am and finished just before they needed power back.

The South Boston bridge spans over the Red Line and MBCR commuter rail tracks and was inspected with ladders even though it was a larger span consisting of prestressed concrete butted box beams in good condition. We decided to use ladders since we could inspect the commuter rail portion starting at 10pm and finish before the MBTA would allow us access to the Red Line around 2am. There was also a small portion over a dirt road with no traffic at 1am. Working in all three sections could not be accomplished using a hi-rail lift since the truck would require traveling further south to be able to get onto the tracks.

The Brookline bridge spans over the Green Line near the Beaconsfield Station and was inspected with a 40 foot hi-lift since the bridge was wide and consisted of 57 rolled steel beams. We were able to get on right near the bridge just after 1am and finished the wide bridge just before power was needed back.

Transit Steel Trapezoidal Box Girder

A few weeks ago I inspected a two span continuous steel trapezoidal box girder which carries the subway over Leveret Circle in Boston. The bridge consists of curved two box girders, a composite deck and reinforced concrete substructure. The viaduct was constructed as part of the Green Line Relocation Project from Haymarket Station to Science Park Station with an original design loading of Green Line Passenger Car.

Constructed in May 2005, The bridge spans 135 feet over gravel and 162.75 feet over Leveret Circle. The bridge has a maximum width of 30 feet out to out. 

The concrete composite deck has hairline cracks in the negative moment region.

A 45' lift truck was used to inspect the span over Leveret Circle and the span over gravel was inspected by ladder. Each girder's interior was accessed by hatches near ground level over the gravel.

When we tried to access the girders we had to cut the locks off with a grinder but one lock was already removed. When then heard and saw movement inside the girder. A homeless man had been living inside the girder. We notified our police details and they helped escort the tenant who left without incident. Inside the girders were filled with an accumulation of homeless peoples debris making for a difficult and unpleasant inspection.

Rules of the hole.....