CALCULATORS / CIVIL, GEOTECHNICAL AND WATER SCREENING

Earthwork cut and fill calculator

Rectangular excavation with supplied bulking factor; no side slopes.

civil-earthwork.napkin / editable

SCENARIO COMPARISON

Compare the numbers.

This source describes an analytical model. Its quantities and checks are the view.

Scenario	inSitum^3	loosem^3
	20	24
	16	19.2

All calculated quantities are listed with the inputs. Switch to Source to inspect the equations.

SCENARIOS / CALCULATED VALUESSAME SOURCE

Change an input to see the consequences.

haul volume budget24.00 m^3✓ passes

BASELINE INPUTS

length10 mwidth2 mdepth1 mbulking1.2

CALCULATED

inSitu20 m^3

loose24 m^3

Edits change the baseline source.

THE SOURCE

Edits below update the same model.

# Earthwork cut and fill
# Scope: Rectangular excavation with supplied bulking factor; no side slopes.
# Status: illustrative worked example; engineering review pending.
# Inputs are example values. Checks are editable example requirements, not standards.

length = 10 m
width = 2 m
depth = 1 m
bulking = 1.2

inSitu := length*width*depth [m^3]
loose := inSitu*bulking [m^3]

check haul volume budget: loose <= 30 m^3

scenario alternative: length = 8 m

Calculated from your source · not saved

Baseline · 10 m reach · 1 m depth

haul volume budget24.00 m^3 ✓ passes

alternative · 8 m reach · 1 m depth

haul volume budget19.20 m^3 ✓ passes

Illustrative first-order example. Checks are editable requirements, not design standards. The broader topic may require additional equations, data, and validation.

Formula and units

This example uses the following equations. Input names and units match the editable source above.

in situ: inSitu = length*width*depth [m^3]
loose: loose = inSitu*bulking [m^3]

Original worked example

These are the baseline values in the downloadable source. Edits above let you test your own values.

Given

length: 10 m
width: 2 m
depth: 1 m
bulking: 1.2

Calculated

in situ: 20 m^3
loose: 24 m^3

Assumptions and limits

Rectangular excavation with supplied bulking factor; no side slopes.

The requirement checks use the limits written in this example. Passing a check does not establish that the model covers every load, material behavior, or operating condition in a real design.

Download this .napkin example ↓

Take it further with your agent

Napkin keeps the inputs, equations, checks and assumptions together in one study. Your agent sets it up; you change the numbers.

Try with Claude ↗

codex 'Use Napkin (https://napkin.engineering/mcp, or the local Napkin plugin) to build a study: Earthwork cut and fill. Inputs: cross sections; elevations; area spacing; bulking factors. Outputs: cut/fill volumes; haul volume estimate. Model scope: Preliminary geometry and loads; site/code inputs supplied externally. Read napkin_capabilities and the current snapshot. Ask me for the values that matter, label assumptions with units, author .napkin source, validate it and apply it with napkin_source using the current revision, then open the study. Add checks for the limits I supply. Keep unsupported analyses explicit.'

Claude needs the Napkin connector; Codex needs the Napkin plugin. Set up your agent ↗

The broader study

The topic brief below describes the broader scope. The worked example above states the particular calculation it implements.

Inputs: cross sections, elevations, area spacing, bulking factors
Outputs: cut/fill volumes, haul volume estimate
Modes: calculate, compare, sweep
Drawing: Load and site section diagram

EXECUTABLE WORKED EXAMPLE · FIRST-ORDER MODEL · CHECK THE SCOPE & ASSUMPTIONS