Report - Oregon State Library: State Employee Information Center ...

Nineteen bridges were also damaged along a 35-km stretch of highway on the Copper River.
Most of these bridges sustained moderate to severe deformations with spans collapsing in at least
six crossings. Prevalent types of failure included severe abutment deformation and vertical
displacement of foundations. At Bridge 334 shown in Figure 2.10(a), damage occurred as a
result of differential pier settlement. Extensive deposits of sand and gravel dominate the Copper
River region, where considerable evidence of liquefaction was present in the form of fissures and
subsidence craters with adjacent ejected soil. Extensive post earthquake settlement of the
approach fill was also evident at Bridge 334 as shown in Figure 2.10(b).
Figure 2.10(a): Collapsed Bent and Deck of Copper River 5 Bridge 334, Mile 35.0, Copper River Highway
Figure 2.10(b): Post-earthquake Settlement at Copper River Bridge 334
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