Earth Support Corp

Earth Support · Seaport

Soldier Pile & Tieback Shoring, Seaport

A deep basement excavation sat directly against an occupied structure over Boston's fill and marine clay, with no room for a sloped open cut.

123456
Schematic — illustrative, not for construction; pending PE review.

The problem

A deep basement excavation sat directly against an occupied structure over Boston's fill and marine clay, with no room for a sloped open cut.

The engineered approach

A soldier pile and lagging wall with two rows of stressed tiebacks was sequenced in lifts to limit ground movement and keep the dig on the critical path.

Outcomes for the GC

  • Kept the foundation on the critical path
  • No measurable settlement to the adjacent structure
  • Zero recordable safety incidents

How we built it

A schematic section of the earth support system for this Seaport job. Scroll to build it in construction order, or select a callout to read the detail.

Schematic cross-section of the Seaport soldier-pile and lagging shoring wall with two rows of stressed tiebacks retaining a deep basement cut against an occupied neighbor.An illustrative section through the Boston Seaport support-of-excavation system. On the retained left side an occupied adjacent building sits at existing grade over deep urban fill and thick Boston blue marine clay; on the right a deep basement is excavated in lifts. Driven steel wide-flange soldier piles are spaced along the wall line and continue below the excavation subgrade, socketing through dense glacial till into argillite bedrock at the toe. Timber lagging spans horizontally between the pile flanges to retain the fill and clay as each lift is dug. Two rows of stressed tiebacks — an upper row and a lower row — are drilled on a downward incline through a sheathed unbonded (free) length, past the theoretical failure surface, into a grouted bond length in competent ground; each tendon is tensioned against a steel waler at the wall face to resist lateral earth pressure and limit movement of the neighbor. Subsurface bands from top to bottom are urban fill, Boston blue clay, glacial till, and argillite bedrock. Schematic only, not to scale, pending professional-engineer review.Urban FillBoston Blue ClayGlacial TillArgillite / Bedrock
Schematic — illustrative, not for construction; pending PE review.

Callouts

Select a numbered part below to read what it is and what it does.

All projects

Ready to scope your foundation?

Tell us about the project and we'll put together a detailed quote within 3 days. We generally work with general contractors.

Get Your 3-Day Quote+1 978 846 6851
CallStart Quote