# Scope by code

What Rischio computes for footings under AASHTO LRFD, 10th edition, article by article: each check and method, computed, in part or not.

Each check and method the code asks of a footing, in the code’s order, and whether Rischio computes it. The list comes from the engine itself, so it changes with every release.

## AASHTO LRFD, 10th edition

| Article | What the code asks | Rischio |
| --- | --- | --- |
| 10.6.1.1 | 
Spread footings: isolated, strip and combined footings (mats as combined footings)

 | In part |
| 3.4.1, Table 3.4.1-1 | Strength I: basic vehicular use without wind |
| 3.4.1, Table 3.4.1-1 | Strength II (permit vehicle), III (wind on structure), V (vehicle with wind) |
| 3.4.1, Table 3.4.1-1 | Service I: all loads at 1.00 |
| 3.4.1, Table 3.4.1-1 | Extreme Event I: γp 1.00, γEQ on LL project-specific, EQ 1.00 |
| 3.4.1, Table 3.4.1-1 | Extreme Event II: ice, vessel or vehicle collision, check flood |
| 3.11.5.4; C3.4.1 | 

Passive earth pressure: a resistance, no load factor (kp for Rep)

 | Not computed |
| 10.6.1 | 

General considerations

 | In part |
| 10.6.1.2 | 

Bearing depth: top of footing below the scour check flood's scour; base below frost

 | In part |
| 10.6.1.3 | 

Effective dimensions B′ = B − 2eB, L′ = L − 2eL, for bearing and settlement

 | Computed |
| 10.6.1.3; C10.6.1.3 | 

A footing that is not rectangular: similar procedures, by judgment

 | Computed |
| 10.6.1.4; 11.6.3.2 | 

Bearing stress on soil: uniform over the effective area

 | Computed |
| 10.6.1.4; 11.6.3.2 | 

Bearing stress on rock: linear (triangular or trapezoidal)

 | Not computed |
| 10.6.1.7 | 

Uplift: resistance to uplift and structural strength

 | Not computed |
| 10.6.1.8 | 

Nearby structures: effects both ways

 | Not computed |
| 10.5.2, 10.6.2 | Service limit state |
| 10.5.2.1, 10.6.2.1 | 

Vertical movement: total and differential settlement

 | In part |
| 10.6.1.3 | 

Settlement on B′ × L′ with the load at its centroid

 | Computed |
| 10.6.2.4.1, Figure 10.6.2.4.1-1 | 

Stress below the footing: zone of influence; Boussinesq contours

 | Computed |
| 10.6.2.4.1, Eq. 10.6.2.4.1-1 | 

St = Se + Sc + Ss, each layer by its own procedure

 | Computed |
| 10.6.2.4.2c | 

Schmertmann method: Iz diagrams by L/B, C1, C2, E from N160 or qc times X

 | Computed |
| 10.6.2.4.2a | 

Elastic theory

 | Computed |
| 10.6.2.4.3, Eqs. 10.6.2.4.3-1 to -3 | 

Primary consolidation from void ratio: OC, NC, underconsolidated

 | In part |
| 10.6.2.4.3, Eqs. 10.6.2.4.3-4 to -6 | 

Primary consolidation from vertical strain (Crε, Ccε)

 | Not computed |
| 10.6.2.4.3, Eq. 10.6.2.4.3-7, Fig. -3 | 

Three-dimensional consolidation where B is small against Hc: μc (EPRI 1983)

 | Not computed |
| 10.6.2.4.3, Eq. 10.6.2.4.3-8, Fig. -4 | 

Time to a degree of consolidation, t = T Hd²/cv

 | Computed |
| 10.6.2.4.4 | 

Settlement on rock: < 0.5 in. on fair to very good rock; else ρ = qo(1 − ν²) r Ip / (144 Em)

 | Not computed |
| 10.5.2.2.1; 10.6.2.2 | 

Tolerable movement criteria: empirical procedures or structural analyses

 | Computed |
| 10.5.2.2.2; C10.6.2.4.2a | 

Differential movement between foundations; 0.5 in. minimum differential

 | Not computed |
| 10.5.2.1; 10.5.2.2.1 | 

Horizontal movement and rotation under all service combinations

 | Not computed |
| 10.5.2.1; 10.5.5.1 | 

Scour design flood: deflection criteria after scour, φ 1.0

 | Not computed |
| 10.6.2.5.1; Table C10.6.2.5.1-1 | 

Presumptive bearing resistance, at the service limit state only

 | Not computed |
| 10.6.2.5.2 | 

Rock: by RMR, capped by qu and 0.3 f′c

 | Not computed |
| 10.5.2.3 | 

Abutment transitions: movements from the embankment behind

 | Not computed |
| 10.5.3.1, 10.5.3.2, 10.6.3 | Strength limit state |
| 10.6.3.1.1, Eq. 10.6.3.1.1-1 | 

Bearing on soil: qR = φb qn ≥ factored pressure on B′L′, each combination

 | Computed |
| 10.6.3.1.2a, Eqs. 10.6.3.1.2a-1 to -4 | 

qn = c Ncm + γq Df Nqm Cwq + 0.5 γf B Nγm Cwγ

 | Computed |
| 10.6.3.1.2a | 

qn by accepted soil mechanics theories: Meyerhof's general bearing capacity equation, chosen

 | Computed |
| 10.6.3.1.2c, Tables 10.6.3.1.2c-1 and -2 | 

Footings on or near slopes: qn × RCBC (Leshchinsky and Xie), by the slope stability factor Ns

 | Not computed |
| 10.6.3.1.2e, Eqs. -1 to -3 | 

Undrained, stronger over softer: Nm = 1/βm + κ sc Nc ≤ sc Nc

 | Computed |
| 10.6.3.1.2e, Fig. 10.6.3.1.2e-2 | 

Undrained, softer over stiffer: Nm from EPRI's chart

 | Not computed |
| 10.6.3.1.2f, Eq. 10.6.3.1.2f-1 | 

Drained upper layer over a weaker one

 | Computed |
| 10.6.3.1.3 | 

Semi-empirical bearing from in-situ tests

 | Not computed |
| Eq. 10.6.3.1.3-1 | 

SPT in sand: qn = (N160 B/5)(Cwq Df/B + Cwγ), N160 over 1.5B

 | Not computed |
| Eq. 10.6.3.1.3-2 | 

CPT: qn = (qc B/40)(Cwq Df/B + Cwγ), qc over B

 | Not computed |
| 10.6.3.2.1 | 

Bearing on rock: discontinuities, weathering; RMR where competency is not evident

 | Not computed |
| 10.6.3.2.2 | 

Semi-empirical: correlation with the Geomechanics RMR

 | Not computed |
| 10.6.3.2.3 | 

Analytic: rock mass strength, failure through discontinuities

 | Not computed |
| 10.5.3.2; 10.6.3.3 | 

Eccentricity (overturning) with factored loads

 | Computed |
| 10.6.3.3 | 

On soil: e ≤ B/3 and L/3

 | Computed |
| 10.6.3.3 | 

On rock: e ≤ 0.45B and 0.45L

 | Not computed |
| 10.6.3.4, Eq. 10.6.3.4-1 | 

Sliding: RR = φτ Rτ + φep Rep ≥ factored horizontal load

 | In part |
| Eq. 10.6.3.4-2 | 

Cohesionless: Rτ = C V tan φf, C 1.0 cast against soil, 0.8 precast

 | In part |
| 10.6.3.4, Fig. 10.6.3.4-1 | 

Clay on ≥ 6 in. of compacted granular material: lesser of su and half the normal stress

 | Computed |
| 10.6.3.4; C10.6.3.4 | 

Passive resistance Rep available through the design life; its future removal

 | Not computed |
| 10.5.3.1; 10.6.3.5; 10.5.5.2.1; 3.4.1 | 

Overall stability, Strength I with γEV 1.00 and φ of 11.6.3.7

 | Not computed |
| 10.5.4.1; 10.6.4.1 | Extreme event limit state |
| 10.6.4.1; 10.5.5.3.3 | 

Bearing resistance, Extreme Event I loads, φ 1.0

 | In part |
| 10.6.4.2; 11.6.5.1 | 

Eccentricity: middle 2/3 at γEQ 0 to middle 8/10 at γEQ 1.0, linear; γEQ 0 if LL reduces e

 | In part |
| 10.6.4.1; 10.5.5.3.3 | 

Sliding, φ 1.0

 | In part |
| 10.6.4.1; 3.4.1 | 

Overall stability, Extreme Event I

 | Not computed |
| 10.5.5.3.2 | 

Scour check flood: φ 1.0, with debris loads

 | In part |

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Source: https://rischio.io/docs/shallow-foundation/scope/