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
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
Additional Projects
South
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Since the early 1980s, SGH has worked with Crom Corporation to assist them in their tank designs. The elevated tanks, with a capacity of between 1.5 MG and 2.0 MG, are thin prestressed concrete shell structures.
South
White Rock North, Water Transmission Main Failure Investigation
The White Rock North Water Transmission Main is a prestressed concrete cylinder pipeline, embedded cylinder type, which delivers 200 million gallons a day of treated water. SGH was hired as a subconsultant to perform a failure investigation of the transmission main after a pipe segment ruptured.


