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Workflow Playbook
Organize soil, groundwater, geometry, loading, and drainage assumptions before screening shallow-foundation capacity, infinite-slope stability, and Rankine active earth pressure. Calculator output is preliminary only.
New to this workflow? Follow the steps in order, starting with the first tool below. Already know what you need? Jump straight to the matching step — every tool in this workflow is listed in the comparison table.
First tool: Bearing Capacity Calculator (Terzaghi)
Hubs
| Tool | What it does | Category |
|---|---|---|
| Bearing Capacity Calculator (Terzaghi) | Calculate the Terzaghi ultimate bearing capacity of a shallow foundation: q_ult = c·Nc·sc + q·Nq·sq + 0.5·γ·B·Nγ·sγ. Computes Nc/Nq/Nγ and shape factors automatically; supports strip, square, and circular footings. Result in kPa. | Math & Numbers |
| Slope Stability Calculator (Infinite Slope) | Calculate the infinite-slope factor of safety: FS = c'/(γ·z·cosβ·sinβ) + tanφ'/tanβ. Supports dry slopes and seepage parallel to the slope. Returns FS and a stable/marginal/unstable classification. | Math & Numbers |
| Active Earth Pressure (Rankine) | Calculate the Rankine active earth pressure on a smooth vertical wall backfilled with cohesionless soil. K_a = tan²(45°−φ/2). Optional uniform surcharge q. Returns the base pressure p₀, the total force P, and the resultant height. | Math & Numbers |
Hubs
This workflow is for geotechnical and civil engineering students, technicians, and engineers preparing an early screening note. The expected result is an auditable set of preliminary values and assumptions, not a statement that a site, footing, slope, or wall is safe. Identify whether the question concerns shallow-footing resistance, an infinite-slope screen, active pressure on a retaining-wall idealization, or a combination.
Before calculating, record cohesion, friction angle, unit weight, stress basis, dry or saturated condition, groundwater level, seepage direction, drainage, geometry, loads, surcharge, units, and uncertainty. Describe footing shape, B and Df, slope beta and z, or wall H. State the factor-of-safety criterion that a reviewer will apply.
Use bearing-capacity-calculator for Terzaghi ultimate capacity of a strip, square, or circular shallow footing. It produces q_ult and bearing factors but has no groundwater or applied-load input. Use slope-stability-calculator for the infinite-slope equation: dry means no seepage, while parallel uses saturated and water unit weights for seepage idealized parallel to the slope. Save FS, driving shear, contributions, and classification.
Use active-earth-pressure only for a smooth vertical wall with cohesionless backfill and optional uniform surcharge. Save Ka, base pressure, total force P, and resultant height. Since it has no groundwater input, hydrostatic pressure and other wall actions remain separate review items.
Do not call every favorable number a safety factor. q_ult is not an applied-load comparison, and wall force P is not a factor of safety. Compare slope FS with the written project criterion, then separately compare foundation pressure and wall actions with the required checks. Common failures include omitting a rising water table, using dry weight in a saturated or seepage case, applying the wall model to a rough or inclined wall, and treating an infinite-slope result as a complete landslide assessment. The calculator output is not a site investigation, geotechnical report, construction approval, or replacement for qualified engineering review.
Workflow playbook
Write the screening question and preserve soil parameters, groundwater level or seepage direction, drainage state, geometry, units, applied foundation load or pressure, wall surcharge, and review criterion before opening a calculator.
Use bearing-capacity-calculator with strip, square, or circular shape, cohesion c, friction angle phi, unit weight gamma, footing width B, and embedment Df. Record Nc, Nq, N-gamma, shape factors, surcharge, capacity terms, and ultimate q_ult in kPa. Compare q_ult with applied pressure only through a separately stated review method; the tool has no groundwater or applied-load input.
Use slope-stability-calculator with effective c-prime, effective phi-prime, beta, z, and gamma. Select dry for no seepage or parallel when seepage is idealized parallel to the slope, then provide gamma-sat and gamma-w for parallel mode. Record FS, driving shear, contributions, and classification without treating it as a site-wide landslide assessment.
Use bearing-capacity-calculator for Terzaghi ultimate capacity of a strip, square, or circular shallow footing. Use slope-stability-calculator for its infinite-slope dry or slope-parallel-seepage model. Use active-earth-pressure for Rankine pressure on its stated smooth vertical wall and cohesionless backfill model.
Choose dry or parallel seepage in the slope tool only when that idealization matches the observed drainage direction. The bearing and active-pressure tools have no groundwater input, so record water levels and hydrostatic or pore-pressure concerns separately rather than silently treating wet soil as dry.
Check footing shape, B, Df, slope beta and z, or wall H. Record actual loads, surcharge, drainage state, and boundary conditions separately because these simplified tools do not cover every eccentric, layered, transient, seismic, or structural interaction.
Record the slope FS and classification and compare them with a project-specific criterion. Treat bearing q_ult and wall force P as calculated resistance or action values, not safety factors; state how a reviewer will compare them with applied loads and other required checks.
Use active-earth-pressure only for its smooth vertical wall with cohesionless backfill model. Enter phi, wall height H, unit weight gamma, and optional uniform surcharge q. Record Ka, base pressure, soil and surcharge forces, total force P, and resultant height. Document groundwater separately because the tool has no water input.
Check units, geometry, drainage mode, and whether each result answers the intended question. Compare slope FS and classification with the stated criterion; separately review foundation pressure against q_ult and wall actions against structural, sliding, overturning, and foundation checks. Escalate missing investigation data or a mismatched idealization to a qualified geotechnical engineer.