At the overcrossing for Road 27 in Madera County, crews are busy preparing for the placement of concrete girders next month. Here at the northern end of Construction Package 1, the Road 27 overcrossing will take traffic over the high-speed rail line and existing tracks for BNSF.
The Road 27 overpass is a unique structure compared to the others currently being constructed in Madera County. Due to the geometry of Road 27 as it crosses the BNSF and high-speed rail corridor, the spans of this bridge are long.
Design-builder Tutor-Perini/Zachry/Parsons (TPZP) is using precast spliced girders for the superstructure to achieve the distances needed. Shorter precast girders are set on temporary falsework bents. The girders are then post-tensioned and the ends enclosed in concrete to unify the superstructure. Ultimately, the bridge will be over 700 feet long with the longest span stretching 198 feet.