Resources Numerical accuracy
Calculations
Every calculation under our calculation policies: what it works out, its formula and the precision it runs at. Open one to see its code as it is in the released app.
Calculations
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Design plane
The design elevation at a point for a level and two grades.
z = z₀ + gx·(x − cx) + gy·(y − cy)
Earthwork balance and haul plan earthwork.js64-bit- CivilCraft
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Free-haul moment
The volume moved times the distance between the centroid of cut and the centroid of fill.
moment = min(cut × factor, fill) × |centroid(cut) − centroid(fill)|
Earthwork balance and haul plan earthwork.js64-bit- CivilCraft
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Best tilt
The level and tilt, within the grade limit, that balance with the least haul moment.
Earthwork balance and haul plan earthwork.js64-bit- CivilCraft
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Blocks of cut and fill
Cells grouped into blocks, each with its volume and its volume-weighted center.
center = Σ (p × v) ÷ Σ v
Earthwork balance and haul plan earthwork.js64-bit- CivilCraft
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Minimum-cost transport
How much goes from each block of cut to each block of fill at the least total volume times distance.
Earthwork balance and haul plan earthwork.js64-bit- CivilCraft
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Haul plan totals
Volume moved on site, total haul, average haul distance, and what is left to take away or bring in.
haul = Σ volume × distance; average = haul ÷ moved
Earthwork balance and haul plan earthwork.js64-bit- CivilCraft
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Earthwork balancer run
The volumes at the pad's present level, the balanced level, the tilt and the haul plan for one pad.
factor = 1 + percent ÷ 100; cell area = cell²
Earthwork, route and pond tools: values stored and exported eg-ui.js64-bit- CivilCraft
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Balanced level written to the pad
The pad's level, and its corner elevations when it tilts, as stored in the project.
z stored = Number(z.toFixed(3))
Earthwork, route and pond tools: values stored and exported eg-ui.js64-bit- CivilCraft
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Haul plan CSV
The haul flows exported as a CSV file.
Earthwork, route and pond tools: values stored and exported eg-ui.js64-bit- CivilCraft
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Alignment from a found route
The PIs of a new alignment from the route's points, with a curve radius at each bend.
r = min(R, min(l₁, l₂) ÷ (2·tan(Δ/2))), stored to 2 decimals
Earthwork, route and pond tools: values stored and exported eg-ui.js64-bit- CivilCraft
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Route ends picked in the plan
The start and end of a route search as taken from two picked points.
x, y = Number(v.toFixed(3))
Earthwork, route and pond tools: values stored and exported eg-ui.js64-bit- CivilCraft
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Sized orifice written to the pond
The orifice diameter found for the target outflow, as stored in the pond.
diameter stored = Number((d ÷ L).toFixed(3))
Earthwork, route and pond tools: values stored and exported eg-ui.js64-bit- CivilCraft
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Pond hydrograph CSV
Inflow, outflow and stage against time exported as a CSV file.
Earthwork, route and pond tools: values stored and exported eg-ui.js64-bit- CivilCraft
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Survey points for progress checks
Ground points read from a LAS, LAZ, CSV or text file and turned into a surface.
LAS thinning cell = max(0.5, √(extent area ÷ 400 000)) unless a spacing is given
Earthwork, route and pond tools: values stored and exported eg-ui.js64-bit- CivilCraft
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Three-decimal rounding of tool results
The rounding applied to nearly every number a tool returns to an assistant or script.
r3(v) = round(v × 1000) ÷ 1000
Earthwork, route and pond tools: values stored and exported eg-agent.js64-bit- CivilCraft
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Volumes in report units
Volumes converted to cubic yards or cubic meters for a tool's answer.
cubic yards = cubic feet ÷ 27; from cubic meters: ÷ 0.028316846592 ÷ 27
Earthwork, route and pond tools: values stored and exported eg-agent.js64-bit- CivilCraft
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Rain results in inches and cubic feet per second
Depths and flows from the rain solver converted from meters for a feet project.
inches = meters × 39.3700787; ft³/s = m³/s ÷ 0.028316846592
Earthwork, route and pond tools: values stored and exported eg-agent.js64-bit- CivilCraft
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Pad level set by an assistant
A pad's level and, for a tilted pad, its corner elevations, as stored in the project.
z stored = r3(level); corner z = r3(level + gx·(x − cx) + gy·(y − cy))
Earthwork, route and pond tools: values stored and exported eg-agent.js64-bit- CivilCraft
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Alignment from route points
The PIs of an alignment made by an assistant from route points, with curve radii.
r = min(R, min(l₁, l₂) ÷ (2·tan(Δ/2))), stored to 3 decimals
Earthwork, route and pond tools: values stored and exported eg-agent.js64-bit- CivilCraft
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Orifice sized by an assistant
The orifice diameter found for an allowed outflow, as used for the reported run.
diameter = r3(d ÷ L)
Earthwork, route and pond tools: values stored and exported eg-agent.js64-bit- CivilCraft
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Number of pieces for an arc
How many straight pieces draw an arc within the tolerance.
step = min(2·acos(1 − tol ÷ r), 5°); pieces = ⌈|sweep| ÷ step⌉, from 1 to 720
Feature line arcs as straight pieces featureline.js64-bit- CivilCraft
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Line as straight pieces
The feature line with every arc replaced by vertices on the arc.
p = c + r·(cos θ, sin θ), θ = a₀ + sweep × s ÷ k; z = z_a + (z_b − z_a) × s ÷ k
Feature line arcs as straight pieces featureline.js64-bit- CivilCraft
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Closed design line as a grading item
The outline and the single elevation a closed design feature line passes to grading.
z = Σ vertex z ÷ number of vertices
Feature line arcs as straight pieces featureline.js64-bit- CivilCraft
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Feature line written to DWG or DXF
The 3D polyline and the extended data that records which runs of pieces were arcs.
Feature line arcs as straight pieces featureline.js64-bit- CivilCraft
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Feature line read back from DWG or DXF
The feature line rebuilt from a polyline and its extended data.
Feature line arcs as straight pieces featureline.js64-bit- CivilCraft
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Crossings with an alignment
Every place a feature line crosses the centerline, with its station and elevation.
z = z_a + t × Δz
Feature line arcs as straight pieces featureline.js64-bit- CivilCraft
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Stretches running beside an alignment
The parts of a feature line within a given distance of the centerline, as station and elevation for a profile view.
Feature line arcs as straight pieces featureline.js64-bit- CivilCraft
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Project units to meters
The factor that takes a project length to meters for every engine in this file.
feet: 0.3048; meters: 1
Running saved geotechnical, survey, pit and link items geo-run.js64-bit- CivilCraft
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Soil profile along a section
The borings in meters, the layers between them, and the layer stack at evenly spaced stations.
stations = max(2, round(length ÷ step)), default step = max(length ÷ 40, 0.5 m)
Running saved geotechnical, survey, pit and link items geo-run.js64-bit- CivilCraft
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Slope cross section for stability
The ground line, layer tops, water level, surcharges and floor that the slope stability engine reads.
81 samples along the section; layer top = min(layer top, ground)
Running saved geotechnical, survey, pit and link items geo-run.js64-bit- CivilCraft
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Slope stability run
The factor of safety of a given circle, or the critical circle from a search.
Running saved geotechnical, survey, pit and link items geo-run.js64-bit- CivilCraft
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Settlement run
Settlement under a footing at a boring, and the time for 50 % and 90 % consolidation.
layer top = (z − from) × k; drainage path = clay thickness ÷ 2
Running saved geotechnical, survey, pit and link items geo-run.js64-bit- CivilCraft
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Traverse run
A traverse closed by the compass rule from legs typed as distance and azimuth in degrees.
azimuth in radians = degrees × π ÷ 180
Running saved geotechnical, survey, pit and link items geo-run.js64-bit- CivilCraft
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Radio link run
Path length, terrain profile, line of sight, link budget and mast height for a link between two points.
distance in km = √(Δx² + Δy²) ÷ 1000
Running saved geotechnical, survey, pit and link items geo-run.js64-bit- CivilCraft
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Coverage run
Received power over a grid round a transmitter and the farthest covered cell.
farthest = max over covered cells of √(Δx² + Δy²) ÷ k
Running saved geotechnical, survey, pit and link items geo-run.js64-bit- CivilCraft
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Open pit run
The block model in meters, block values, the ultimate pit and its phases.
slope in radians = degrees × π ÷ 180; phase factors from 0.4 to 1 in equal steps
Running saved geotechnical, survey, pit and link items geo-run.js64-bit- CivilCraft
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Unit weight of water
The constant behind every pore pressure and every submerged unit weight in this file.
γw = 9.81 kN/m³
Slope stability geotech.js64-bit- CivilCraft
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Elevation of a line at a position
The ground, a layer top or the water table at a horizontal position.
Slope stability geotech.js64-bit- CivilCraft
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Where a circle meets the ground
The positions where the lower arc of a trial circle crosses the ground line.
f(x) = ground(x) − (zc − √(R² − (x − xc)²))
Slope stability geotech.js64-bit- CivilCraft
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Slices of the sliding mass
Each slice's width, weight, base angle, strength and pore pressure.
W = Σ layers γ × thickness × b; sin α = −(x − xc) ÷ R; u = γw × (zw − zb), or ru × W ÷ b
Slope stability geotech.js64-bit- CivilCraft
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Factor of safety
The factor of safety of one circle by the ordinary method or by Bishop's simplified method.
Bishop: FS = Σ[(c·b + (W − u·b)·tan φ) ÷ (cos α + sin α·tan φ ÷ FS)] ÷ Σ W·sin α
Slope stability geotech.js64-bit- CivilCraft
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Critical circle search
The circle with the lowest factor of safety among those tried.
Slope stability geotech.js64-bit- CivilCraft
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Stress influence factor under a corner
The share of the surface load felt at a depth under the corner of a loaded rectangle.
m = a ÷ z, n = b ÷ z, v = m² + n² + 1; I = [2mn√v ÷ (v + m²n²) × (v + 1) ÷ v + atan2(2mn√v, v − m²n²)] ÷ 4π
Foundation settlement geotech.js64-bit- CivilCraft
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Stress under a footing
The vertical stress increase under the center or a corner of a rectangular footing.
center: Δσ = 4·q·I(B ÷ 2, L ÷ 2, z); corner: Δσ = q·I(B, L, z)
Foundation settlement geotech.js64-bit- CivilCraft
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Stress by the 2:1 spread
The average stress increase at a depth by the quick 2:1 rule.
Δσ = q·B·L ÷ ((B + z)·(L + z))
Foundation settlement geotech.js64-bit- CivilCraft
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Elastic settlement under a corner
The settlement of the corner of a flexible loaded rectangle on an elastic half-space.
w = q·(1 − ν²) ÷ (π·E) × [a·ln((b + d) ÷ a) + b·ln((a + d) ÷ b)], d = √(a² + b²)
Foundation settlement geotech.js64-bit- CivilCraft
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Settlement of a layered soil
Consolidation and immediate settlement under a footing, sub-layer by sub-layer.
clay: s = Cc·Δz ÷ (1 + e₀) × log₁₀(σ′f ÷ σ′₀), with Cs below σ′c; sand: s = Δσ ÷ Es × Δz
Foundation settlement geotech.js64-bit- CivilCraft
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Degree of consolidation
The share of the final consolidation settlement reached at a time factor.
U = 1 − Σ (2 ÷ M²)·exp(−M²·Tv), M = π·(2m + 1) ÷ 2
Foundation settlement geotech.js64-bit- CivilCraft
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Time factor for a degree of consolidation
The time factor at which a given share of the settlement is reached.
Foundation settlement geotech.js64-bit- CivilCraft
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Time to reach a degree of consolidation
The time for a share of the consolidation settlement.
t = Tv·Hdr² ÷ cv
Foundation settlement geotech.js64-bit- CivilCraft
A calculation is added only after its source was read. Each statement can be checked in the code shown on its policy's page; the app repositories are public. When a release changes a calculation, its page says so until it has been read again.