Morenci, AZ

Precast Concrete Arch

Scope/Solutions

A precast concrete arch allowed mine vehicles to pass over U.S. Highway 191. A few months after the buried bridge was put into service, the mine operator observed separation of the headwall panels and longitudinal cracks in the highway, indicating differential settlement between the two footings. They retained SGH to investigate the bridge’s condition.

SGH used construction documents and field measurements to develop finite element models and evaluate the structural capacity of the bridge. Highlights of this work include:

  • Creating two- and three-dimensional models of the arch to analyze soil-structure interaction and the effects of the differential settlement on the structure
  • Calibrating our results to the field measurements of the settlement and change in span resulting from the footing movement
  • Evaluating the capacity of the arch, considering the settled condition

Our analysis helped demonstrate that bridge still had sufficient capacity despite the settlement and could remain in service.

Project Summary

Icon: completion-date

2021

Completion Date
Solutions
Failure Investigation
Services
Structures | Advanced Analysis
Markets
Infrastructure & Transportation
Client(s)
Freeport-McMoRan
Specialized Capabilities
Repair & Strengthening | Marine & Civil Works | Buried Infrastructure | Computational Mechanics | Failure Analysis

Key team members

Jesse Beaver
Executive Principal, Engineering Mechanics and Infrastructure

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