Emlenton Walls – Contractor Alternate Design

PennDOT District 1-0

 Project Manager: Ray Henney, PE
Phone: 412.392.8788

Completion Date: 2014

SAI was responsible for the re-design of six (6) retaining walls for the realignment of SR 0038 between Exit 42 of I-80 and the SR 0268 intersection near the bridge over the Allegheny River into Emlenton Borough.

Project features include:

  • The retaining walls had to account for difficult site conditions.
  • At Wall 4, the roadway was relocated away from the hillside, which required a need for a wall with a maximum exposed wall height of 50′ and a total length of 360′.
  • For the alternate design, a premium was placed on eliminating as many rock anchors as possible due to the high installation cost per anchor and the difficulty in accessing them, 35 anchors were eliminated from the design (116 to 81).
  • To facilitate construction, wood lagging was designed to support the entire backfill load during construction during all phases of the wall installation.
  • Finite-element models were created for each final condition design height and for each stage during the bottom-up construction. Redundancy was checked by assuming a failed anchor in the finite element model.
  • Two soldier pile walls were redesigned as conventional concrete cantilever walls with spread footings to provide additional savings.
  • The alternate walls were completed on schedule.

Project Owner: PennDOT District 1-0
Contact: Mekis Construction Company
Phone: 724.283.6200