Contractor: Williams Brothers Construction Co.
Structural Engineer: URS Corporation
Owner: TxDOT, Houston District
IH-10 and Beltway 8 Interchange
The structures included in this project consisted of eight direct connectors – including both single lane and two lane sections – as well as two IH-10 frontage road flyovers and the mainline IH-10 grade separations. All eight of the single lane direct connectors utilized steel trapezoidal box girders. The four left turn direct connectors were curved with radii ranging from 818 to 1,393 feet, and spans ranging from 163 to 366 feet. The four outside right turn direct connectors were set on curved alignments with radii of 573 feet and spans ranging from 104 to 260 feet. The longer approach spans also incorporated trapezoidal steel box girders and had both constant and variable width sections, with a maximum single span design of 305 feet. Two additional frontage road flyover structures, parallel to the Beltway 8 bridges, were added to alleviate high traffic volume concerns at the frontage road intersections. These flyovers along Beltway 8 were also designed with trapezoidal steel box girder superstructures.
The design of the IH 10 / Beltway 8 interchange project had to accommodate a complete reconstruction of a fully directional interchange, believed to be a first for Texas, while maintaining all traffic movements throughout construction. This was accomplished by utilizing the structural advantages of trapezoidal steel box girders, with radii as tight as 573-feet and spans up to 366-feet, which allowed the engineers to minimize the number of temporary and permanent bents.
Trapezoidal steel box girders give the structures cleaner lines. When driving under these direct connectors that are elevated 80 to 100-feet in the air, the public notices and appreciates the enhanced aesthetics.
Written by: Cliff R. Hall, PE – URS Bridge ManagerURS Project Team:
Brent Kyler, PE – Project Manager
Cliff R. Hall, PE – Bridge Manager
Scott Montgomery, PE – Project Bridge Engineer, Direct Connectors
Arthur Champlin, PE – Project Bridge Engineer, Approach Spans
A.J. Widacki, PE – Project Engineer, Construction Phase Services