SEI - IL APRIL WEBINAR: SR-43 Concrete Tie Arch, CAHSR CP 2-3 

Presented by Hadi Al-khateeb (Jacobs)

The California High Speed Rail Construction Package 2-3, delivered currently under a design/build project, provides for over 65.5 miles of high-speed rail infrastructure through California’s Central Valley from Fresno to Bakersfield. Designed for a high-speed rail of 250 mph, the project includes several unique concrete bridge types, among them a concrete network tied arch bridge selected to satisfy very tied horizontal and vertical clearance requirements as it spans over SR-43 while maintaining highway traffic below.   

The concrete tied-arch bridge is 236 ft long from center-to-center bearings at the two abutments, and its floor system consists of a 10-inch thick cast-in place (CIP) reinforced concrete deck slab made composite with transverse pretensioned concrete beams framing integrally into CIP post-tensionedconcrete longitudinal tie beams. Inclined steel hanger cables comprised of 3” diameter high strength thread bars connect the tie-beams to the concrete arch ribs that rise 50 feet above the deck. Eradiquake seismic isolation bearings are provided at the abutments to reduce seismic forces.   

The presentation will provide an overview of characteristic structural details and the methods of construction for the arch bridge and discuss unique methods of analyses used to design the bridge including track structure interaction for high-speed rail, non-linear seismic analysis, and hanger cable loss analyses.