SettingsSettings for this calculationUS
The design lateral earth pressure for the braced excavation.
From a Peck-style apparent pressure diagram for the specific soil type (sand, soft clay, or stiff clay), not a simple triangular active pressure distribution — apparent pressure diagrams are typically closer to rectangular or trapezoidal.
The vertical height of wall each strut level is responsible for.
Typically half the distance to the strut level above plus half the distance to the strut level below (or to the excavation base).
The horizontal center-to-center spacing between struts at this level.
Centre to centre along the excavation at the level you are checking, which is not necessarily the spacing at other levels — a braced excavation often has struts closer near the bottom where the pressure is highest. The load scales directly with this, so a strut omitted from a run doubles the spacing around the gap and doubles that strut's load, which is why a missing strut is a design change rather than a convenience.
Strut axial load
109 kips
This is a simplified tributary-area estimate — real braced excavation design uses the full Peck/Terzaghi apparent pressure envelope for the specific soil profile, and should also check strut buckling capacity, connections, and wale bending, all outside this calculator's scope.
They open the calculator with your figures already in it
Excavation Bracing Strut Load Calculator: 109 kips — shown in imperial, US market. The link sets both, so the result they see is the one on your screen.
Show calculation logicHide calculation logic
How this was calculated
Formula source(s)
- Standard tributary-area method for braced excavation strut loads: strut load = design apparent lateral pressure x tributary height x horizontal strut spacing
Inputs used
- Design Apparent Lateral Pressure
- 835.42 psf
- Strut Tributary Height
- 10 ft
- Horizontal Strut Spacing
- 13 ft
Confidence note: This is a simplified tributary-area estimate — real braced excavation design uses the full Peck/Terzaghi apparent pressure envelope for the specific soil profile, and should also check strut buckling capacity, connections, and wale bending, all outside this calculator's scope.
What this calculation does not cover
- It gives the axial load only, not a strut. Nothing here checks buckling capacity, unbraced length, end fixity, wale bending, or the connections at each end, and the strut's own self-weight and the bending it causes on a long span are ignored. Choosing a section from this number is a separate design.
- The apparent pressure is taken as given, never derived. No excavation depth, soil strength, unit weight or wall type is asked for, so the calculator cannot tell you whether the figure you entered matches a Peck envelope for your ground — it simply multiplies what you type.
- Water and surcharge are not added. Hydrostatic pressure from an unrelieved water table, and load from spoil heaps, cranes, traffic or adjacent foundations, must already be inside the pressure you enter. Water alone is roughly 10 kPa (1.5 psi) for every metre (3.3 ft) of head.
- The tributary rectangle assumes a straight, uniform run of wall with regular strut levels at regular spacing. Corner struts, rakers, unequal bays, struts at a change in excavation depth, and the redistribution that happens as levels are installed, preloaded and removed all fall outside it.
- This is a load estimate, not shoring design. Basal heave, wall embedment, ground movement and damage to neighbouring structures are untouched, and none of this replaces a temporary works design and check by a competent engineer.
Add the equipment this sizes
This result is a specification — 109 kips — not a quantity. Put the thing it sizes into your project: how many, what you call it, and your supplier’s price.
Computed in your browser — nothing you enter is uploaded. Presented in US customary units and US trade terminology. Where a formula follows a published standard, that standard and its edition are cited beside it on this page; where none governs, the page says so. Local amendments override model codes — verify against the code in force where you build.
Sources checked 2026-09-06 · in the site-wide review of 2026-09-06 · v1.0.1
Regulatory standards & verification citations1
- Standard tributary-area method for braced excavation strut loads: strut load = design apparent lateral pressure x tributary height x horizontal strut spacing
Cite this page
Your workspace
Most jobs need more than one number. Add the calculators you need next and they open right here, underneath this one — your figures stay on screen and nothing is lost to a page change.