G-8
At G-8, tied-back and raker-braced soldier piles supported excavation near historic buildings. A nearby basement wall constrained the rakers, and a tied-back raker pad provided support while the P4 level was excavated.
Specialty structural engineering
Soldier Pile Shoring Design
Soldier piles, lagging, and bracing designed together for excavations with changing depths, tight boundaries, and limited working room.
How it works
How soldier pile shoring works
Soldier pile shoring uses spaced structural piles with lagging installed between them as excavation proceeds. Depending on depth and site conditions, the wall may work in cantilever or be supported by tiebacks, rakers, or internal braces. Pile installation, ground conditions, bracing, and excavation sequence all affect the design.
Because the system is assembled along the excavation edge, it can adapt to changing heights and constraints. The same flexibility brings coordination work: pile locations must avoid existing foundations and utilities, lagging must follow the excavation, and support members must leave room for the permanent structure.
Site conditions
Soldier pile walls for changing excavation depths and site conditions
A soldier pile wall can use different bracing along the same excavation as depths, neighboring structures, and property rights change. Cefali designs the piles, lagging, and support connections around those conditions, with room for drilling equipment and the permanent foundations.
- Bracing options
- A cantilever wall, tiebacks, rakers, or cross-lot braces may suit different parts of the site.
- Drilling limits
- Existing foundations, utilities, property lines, and transit structures affect pile and anchor placement.
- Excavation stages
- Lagging, walers, and braces must fit the planned sequence and leave room for the permanent work.
Engineering services
Pile, lagging, and bracing design
Cefali & Associates designs soldier pile systems around excavation loads, ground conditions, adjacent structures, and construction access.
- Pile and lagging layout
- The wall layout follows the excavation and accounts for ground conditions, nearby foundations, and utilities that restrict pile locations.
- Bracing coordination
- Tiebacks, walers, rakers, or cross-lot braces provide additional support where piles alone are not sufficient.
- Construction documents
- Detailed-design drawings and calculations set out the piles, lagging, bracing, and connections for drilling, excavation, and permanent construction.
We agree the drawings, calculations, and support during construction with you in the proposal.
Design considerations
Drilling access and bracing shape the pile layout
Piles have to fit where equipment can install them, and their bracing has to work as the excavation gets deeper. Nearby footings, utilities, and the new foundations all affect the layout.
- Pile installation
- Existing footings, utilities, limited headroom, and access affect where equipment can drill and where piles can be placed.
- Lateral support
- Cantilever action, anchors, rakers, and cross-lot braces have different space and property requirements. The choice may change along one wall.
- Wall transitions
- Corners and changes in retained height can require different detailing. The support must also coordinate with slabs, foundations, and eventual brace removal.
In practice / Intuit Dome
The design in practice.
Intuit Dome used cantilever and tieback-braced soldier piles around below-grade work. At the entrance tunnel, a cross-lot braced system replaced tiebacks where agreements could not be secured.
See the Intuit Dome projectMore project examples
Vista Monterey Soil Nails
At Vista Monterey, soldier-pile walls flanked the soil-nail wall where nail easements were not available. The property boundary directly changed which retaining system could be used along different portions of the site.
Related project work
Projects involving soldier pile shoring
See the systems, site conditions, and construction details from these projects.
Before you begin
Common questions
Do soldier pile walls always need tiebacks?
No. The required support depends on excavation height, loads, movement limits, and site access. Cantilever piles or internal bracing may be options in some conditions.
What affects where the piles can go?
Nearby foundations and utilities, drilling clearance, ground conditions, and excavation stages all affect the pile layout.
Can soldier piles be part of a permanent wall?
Yes, when designed for that use. The permanent wall needs details and design criteria for the finished site; a wall designed only for temporary support cannot automatically serve that role.
How is lagging coordinated with excavation?
Lagging is installed as the ground is exposed, so the excavation sequence and access affect the wall detail. The geotechnical recommendations and contractor’s method are important inputs.
Discuss your project
Tell us what you are planning.
Send the drawings, reports, and site information you already have, along with your schedule and the work you need help with. You do not need a complete design package to get in touch.
- Wall line and excavation sections
- Geotechnical recommendations
- Records of nearby footings, utilities, and underground structures
- Anchor-rights limits, access plan, and construction stages