Pine Valley Creek Bridge

Pine Valley Creek Bridge
Nello Irwin Greer Memorial Bridge
Pine Valley, California, United States
440 feet high / 134 meters high
450 foot span / 137 meter span
1974

Image by Tim Farmer.

Pine Valley Creek is the highest concrete beam bridge in the United States with a 4-lane road deck 440 feet (134 mtrs) above the creek along Interstate 8 east of San Diego. It was the first bridge in the United States to be built using the cast-in-place segmental balanced cantilever method. In the center of the bridge an open gap of 11.6 meters was left for the option to add two more lanes of traffic if demand ever warrants it. The two tallest piers are 85 meters or 280 feet.

Completed in 1974 along Interstate 8 about 60 miles (97 kms) East of San Diego, California, the bridge was eventually named the Nello Irwin Greer Memorial bridge after the man who guided the design of the highway through the Pine Valley region.

Famous bridge engineer Man-Chung Tang was the chief designer behind the bridge. Since the construction of a segmental bridge had never been done in California, Mr. Tang and his team had to design everything from scratch including the gantry, travelers and forms. Man-Chung Tang went on to engineer dozens of North American segmental bridges as well as many large bridges in China and Europe. He worked for many years at T.Y. Lin out of their offices in San Francisco and Chongqing. The construction was done by a joint venture between S. J. Groves & Sons Company of Minneapolis and Dyckerhoff & Widmann USA, based in New York City. The latter was a subsidiary of Dyckerhoff & Widmann AG (DYWIDAG) of West Germany. The clean and elegant design was by Bert Bezzone and Joe Bender of Caltrans.

The main spans were created over the deep valley with a form traveler that carried the formwork for the box girder and the working platform. The bridge girder is composed of short segments of 5 meters or 16.4 feet long. Each of the two decks is 12.8 meters or 42 feet wide. The crossing was one of the first in the United States to use rock anchors which reduced the size of the foundations on the steep slopes while also assuring the piers could more easily resist earthquakes.

During construction a 140 meter or 340 foot long steel gantry girder was used to transport workers and materials from pier to pier. The cross section was 3 meters or 10 feet square. The gantry allowed transportation for personnel and material trucks.