PECO was expanding generation at this substation and were adding concrete pads. A deep foundation was required as a suitable bearing stratum was not encountered until 90′ to 110′ below grade. Timber piles caused safety concerns and required shut-downs through-out the plant. Helical piles are a segmented, extendable piling system that mitigate overhead and mobilization issues and were installed while the plant remained in operation. Helicals proved to be such a good fit for this project, that it led to a second and third projects at Edgemoor and a fourth job at a substation south of Wilmington, DE.
Project Summary:
- Helical Pile Type: 1.75 Square Shaft with a 6″ PVC cased Grouted Helical Micropile
- Location: Wilmington, DE
- Installation Depth: 85′-100′
- Ultimate Pile Capacity: 60 kips
- Equipment Used: John Deere 30K Drivehead w/digital torque indicator
- Challenge/Unique Aspect: Weight of Hammer soils required that the helical be grouted and sleeved to alleviate buckling and lateral concerns. Small equipment mitigated mobilization and overhead concerns. Helical installations produce no spoils which was a prerequisite for the project.
- Design: Eclipse Design Services
- Geotechnical: Craig Testing Labs
- General Contractor: Asplund
- Certified Installer: Utility Lines Construction Services
