Location: San Antonio, TX

The roadway expansion added an upper-level bridge for departures from future terminals. The bridge includes a 700’ cast-in-place section and a 1,200’ precast beam section. Work included widening and reconstruction of the lower-level road, which serves as a passenger loading area. Underground utility improvements include data and communication line installation, earth excavation and embankment, retaining walls, concrete paving, curb and gutter installation, and placement of concrete flatwork. The general contractor and specialty subcontractor used a method similar to an old mining technique. “Wood-box tunneling” avoided utility and traffic conflicts during hydronic piping installation. Underground hydronic piping was installed by hand-digging the tunnel while shoring the excavation with large oak timbers. The pipe was installed, and the void filled with grout. Unlike an “open-cut” method, this had minimal impact to surface operations, was done in limited areas and went deeper without disturbing existing utilities. The tunnel went between a parking structure and an existing terminal without impacting traffic flow, which meant two 16” and two 20” pipes were installed 20’ below the roadway. CEC provided design services for the loop road and bridge that included surveying, traffic modeling, subsurface utility investigations, and construction phase services. The Aviation Department also decided to construct a 66” storm drainage outfall line from Airport Boulevard to John Saunders Road under the apron serving San Antonio Aerospace. This required the construction of a 78” bore and steel casing to allow the installation of the storm drainpipe.