Welborn and UPPR Rail Road Underpass

Complete design of a single span, 75 foot bridge by 272 foot wide carrying Wellborn roadway, a Plaza and provide for grade separation of an existing 2 tracks U.P.R.R. railroad crossing in main campus of Texas A&M in College Station.  Innovative design solutions were used to allow for a concrete bridge for railroad, with this large span and column free spaces in the passageway under the bridge.  Such larger free spans normally require the use of steel plate girder beams; however the client preferred a concrete bridge for less maintenance and more appealing look.  The Rail Road bridge in particular was a challenge on which high strength concrete beams were used to allow for longer spans, and system of double row concrete drilled shafts with a large concrete cap were placed at each abutment to resist the large lateral forces of railroad by means of moment level arm.  AREMA Code was used for doing of the RR bridge.  Phased construction allowed for maintaining the existing traffic on roadway and railroad by providing temporary shoofly.

A large open Pedestrian Plaza was planned at north side of this underpass, gradually stepping up to upper ground level, connecting to a 3,800 car West Campus Parking Garage which Scientech also designed.  These high irregular shaped retaining walls and planter walls were accomplished by a system of cantilever retaining drilled shafts and concrete walls to resist the huge lateral loads.  For economy the depth of shafts were varied through the length of passageway and depending on the height of walls.  At some locations under the bridge, the floor of passageway had to be placed under water table which required special design and use of under floor drainage system. Cost was $11.58 million.