Here is a beautiful picture of the Bixby Canyon Bridge in Callfornia at dusk.  The photo reference comes from one of my freshmen engineering students, Todd Fritz.


blog post photo
http://parkerlab.bio.uci.edu/nonscientific_adventures/Arches%20and%20Bridges.htm
photo by Ian Parker, University of California Irvine


Todd writes:

"The  Bixby Creek Bridge is a concrete compression arch bridge located south of San Francisco, CA.  It is 714ft long with a main span 320ft and at a hight of 280ft. it is not the largest, tallest or longest bridge for a long shot. But this bridge surely has bridginess. It has clean and flowing lines and is not cluttered in any means except it has two buttresses that are unnecessary for support but they give the bridge a feeling of strength.  

"The idea for this bridge started when there was a stated need to connect Highway 1 across Bixby Canyon. There were four proposals for this project, one being a 900ft tunnel, another a shorter bridge near the river's head and a third, a bridge on the bluffs which was ruled out due to safety and earthquake concerns. The winning option was to build the Bixby Creek Bridge. The Ward Engineering Co. won the design and was entitled to construct the project. 


"Construction of the bridge started on August 24, 1931 and it was completed on November 27, 1932. The framing (falsework) took two months to complete due to the high winds and loads it needed to support. They used reinforced concrete to save on maintenance and material costs. In 1996 the company Buckland and Taylor retrofitted the bridge to help survive large earthquakes."