Earthwork formulas
Surveying · FE Reference Handbook section
Handbook notes for this section
Definitions and conditions exactly as the handbook states them.
- Average End Area Formula
Core formulas for this FE topic
Definitions, applicability, units, assumptions and worked examples for each relation.
Worked exam-style examples
The four ways this section is written on the real exam — thoughts first, then equations, then substitution.
Two cross sections 30 m apart have cut areas of 24.5 m² and 31.7 m². Compute the volume between them, then the loose volume with 12% swell.
Given
Find
Bank volume and loose (hauled) volume
Start with the thinking
- Average end area is the FE default unless the prismoidal method is requested.
- Swell increases hauled volume relative to bank volume.
Step-by-step solution
Average area
Bank volume
Swell factor
Loose volume — 843(1.12)
Result
843 m³ bank, 944 m³ loose
Why the other options are there
- 1,686 m³ (areas added, not averaged)
- 753 m³ (shrinkage applied instead of swell)
Reference: FE Reference Handbook — Construction — Earthwork volumes
A surveying problem uses Average-end-area earthwork volume. Given station spacing (L) = 430.0 ft; end area 1 (A1) = 397.0 ft²; end area 2 (A2) = 35.0000 ft², determine the volume (V) in ft³.
Given
Find
volume (V), in ft³
Start with the thinking
- The governing relation printed in this handbook section is Average-end-area earthwork volume.
- Everything except V is given, so isolate V symbolically first — never rearrange after the numbers are in.
- Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
- Surveying items reward recognising the unknown before touching a calculator.
Step-by-step solution
Step 1 — State the governing relation:
Step 2 — Rearrange the relation so that V stands alone on the left-hand side.
Step 3
Step 4 — Substitute the given values into the rearranged relation.
Step 5 — Evaluate:
Step 6 — Check: returning V = 92,880 ft³ to
reproduces the given quantities, and both sides carry the same units.
Why the other options are there
- 185,760 — kept a factor of two that cancels in the correct rearrangement.
- 46,440 — dropped that same factor in the other direction.
- 102,168 — rounded an intermediate value before the final step.
Reference: FE Reference Handbook — Surveying → Earthwork formulas
A surveying problem uses Average-end-area earthwork volume. Given end area 1 (A1) = 268.0 ft²; end area 2 (A2) = 46.0000 ft²; volume (V) = 148,838 ft³, determine the station spacing (L) in ft.
Given
Find
station spacing (L), in ft
Start with the thinking
- The governing relation printed in this handbook section is Average-end-area earthwork volume.
- Everything except L is given, so isolate L symbolically first — never rearrange after the numbers are in.
- Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
- Surveying items reward recognising the unknown before touching a calculator.
Step-by-step solution
Step 1 — State the governing relation:
Step 2 — Rearrange the relation so that L stands alone on the left-hand side.
Step 3
Step 4 — Substitute the given values into the rearranged relation.
Step 5 — Evaluate:
Step 6 — Check: returning L = 948.0 ft to
reproduces the given quantities, and both sides carry the same units.
Why the other options are there
- 1,896 — kept a factor of two that cancels in the correct rearrangement.
- 474.0 — dropped that same factor in the other direction.
- 1,043 — rounded an intermediate value before the final step.
Reference: FE Reference Handbook — Surveying → Earthwork formulas
A surveying problem uses Average-end-area earthwork volume. Given station spacing (L) = 385.0 ft; end area 2 (A2) = 164.0 ft²; volume (V) = 129,048 ft³, determine the end area 1 (A1) in ft².
Given
Find
end area 1 (A1), in ft²
Start with the thinking
- The governing relation printed in this handbook section is Average-end-area earthwork volume.
- Everything except A1 is given, so isolate A1 symbolically first — never rearrange after the numbers are in.
- Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
- Surveying items reward recognising the unknown before touching a calculator.
Step-by-step solution
Step 1 — State the governing relation:
Step 2 — Rearrange the relation so that A1 stands alone on the left-hand side.
Step 3
Step 4 — Substitute the given values into the rearranged relation.
Step 5 — Evaluate:
Step 6 — Check: returning A1 = 506.4 ft² to
reproduces the given quantities, and both sides carry the same units.
Why the other options are there
- 1,013 — kept a factor of two that cancels in the correct rearrangement.
- 253.2 — dropped that same factor in the other direction.
- 557.0 — rounded an intermediate value before the final step.
Reference: FE Reference Handbook — Surveying → Earthwork formulas
A surveying problem uses Average-end-area earthwork volume. Given station spacing (L) = 210.0 ft; end area 1 (A1) = 260.0 ft²; end area 2 (A2) = 315.0 ft², determine the volume (V) in ft³.
Given
Find
volume (V), in ft³
Start with the thinking
- The governing relation printed in this handbook section is Average-end-area earthwork volume.
- Everything except V is given, so isolate V symbolically first — never rearrange after the numbers are in.
- Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
- Surveying items reward recognising the unknown before touching a calculator.
Step-by-step solution
Step 1 — State the governing relation:
Step 2 — Rearrange the relation so that V stands alone on the left-hand side.
Step 3
Step 4 — Substitute the given values into the rearranged relation.
Step 5 — Evaluate:
Step 6 — Check: returning V = 60,375 ft³ to
reproduces the given quantities, and both sides carry the same units.
Why the other options are there
- 120,750 — kept a factor of two that cancels in the correct rearrangement.
- 30,188 — dropped that same factor in the other direction.
- 66,413 — rounded an intermediate value before the final step.
Reference: FE Reference Handbook — Surveying → Earthwork formulas
A surveying problem uses Average-end-area earthwork volume. Given end area 1 (A1) = 120.0 ft²; end area 2 (A2) = 298.0 ft²; volume (V) = 100,553 ft³, determine the station spacing (L) in ft.
Given
Find
station spacing (L), in ft
Start with the thinking
- The governing relation printed in this handbook section is Average-end-area earthwork volume.
- Everything except L is given, so isolate L symbolically first — never rearrange after the numbers are in.
- Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
- Surveying items reward recognising the unknown before touching a calculator.
Step-by-step solution
Step 1 — State the governing relation:
Step 2 — Rearrange the relation so that L stands alone on the left-hand side.
Step 3
Step 4 — Substitute the given values into the rearranged relation.
Step 5 — Evaluate:
Step 6 — Check: returning L = 481.1 ft to
reproduces the given quantities, and both sides carry the same units.
Why the other options are there
- 962.2 — kept a factor of two that cancels in the correct rearrangement.
- 240.6 — dropped that same factor in the other direction.
- 529.2 — rounded an intermediate value before the final step.
Reference: FE Reference Handbook — Surveying → Earthwork formulas
A surveying problem uses Average-end-area earthwork volume. Given station spacing (L) = 285.0 ft; end area 2 (A2) = 343.0 ft²; volume (V) = 12,696 ft³, determine the end area 1 (A1) in ft².
Given
Find
end area 1 (A1), in ft²
Start with the thinking
- The governing relation printed in this handbook section is Average-end-area earthwork volume.
- Everything except A1 is given, so isolate A1 symbolically first — never rearrange after the numbers are in.
- Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
- Surveying items reward recognising the unknown before touching a calculator.
Step-by-step solution
Step 1 — State the governing relation:
Step 2 — Rearrange the relation so that A1 stands alone on the left-hand side.
Step 3
Step 4 — Substitute the given values into the rearranged relation.
Step 5 — Evaluate:
Step 6 — Check: returning A1 = -253.9 ft² to
reproduces the given quantities, and both sides carry the same units.
Why the other options are there
- -507.8 — kept a factor of two that cancels in the correct rearrangement.
- -127.0 — dropped that same factor in the other direction.
- -279.3 — rounded an intermediate value before the final step.
Reference: FE Reference Handbook — Surveying → Earthwork formulas
A surveying problem uses Average-end-area earthwork volume. Given station spacing (L) = 395.0 ft; end area 1 (A1) = 384.0 ft²; end area 2 (A2) = 245.0 ft², determine the volume (V) in ft³.
Given
Find
volume (V), in ft³
Start with the thinking
- The governing relation printed in this handbook section is Average-end-area earthwork volume.
- Everything except V is given, so isolate V symbolically first — never rearrange after the numbers are in.
- Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
- Surveying items reward recognising the unknown before touching a calculator.
Step-by-step solution
Step 1 — State the governing relation:
Step 2 — Rearrange the relation so that V stands alone on the left-hand side.
Step 3
Step 4 — Substitute the given values into the rearranged relation.
Step 5 — Evaluate:
Step 6 — Check: returning V = 124,228 ft³ to
reproduces the given quantities, and both sides carry the same units.
Why the other options are there
- 248,455 — kept a factor of two that cancels in the correct rearrangement.
- 62,114 — dropped that same factor in the other direction.
- 136,650 — rounded an intermediate value before the final step.
Reference: FE Reference Handbook — Surveying → Earthwork formulas
A surveying problem uses Average-end-area earthwork volume. Given end area 1 (A1) = 304.0 ft²; end area 2 (A2) = 133.0 ft²; volume (V) = 155,798 ft³, determine the station spacing (L) in ft.
Given
Find
station spacing (L), in ft
Start with the thinking
- The governing relation printed in this handbook section is Average-end-area earthwork volume.
- Everything except L is given, so isolate L symbolically first — never rearrange after the numbers are in.
- Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
- Surveying items reward recognising the unknown before touching a calculator.
Step-by-step solution
Step 1 — State the governing relation:
Step 2 — Rearrange the relation so that L stands alone on the left-hand side.
Step 3
Step 4 — Substitute the given values into the rearranged relation.
Step 5 — Evaluate:
Step 6 — Check: returning L = 713.0 ft to
reproduces the given quantities, and both sides carry the same units.
Why the other options are there
- 1,426 — kept a factor of two that cancels in the correct rearrangement.
- 356.5 — dropped that same factor in the other direction.
- 784.3 — rounded an intermediate value before the final step.
Reference: FE Reference Handbook — Surveying → Earthwork formulas
A surveying problem uses Average-end-area earthwork volume. Given station spacing (L) = 215.0 ft; end area 2 (A2) = 153.0 ft²; volume (V) = 55,937 ft³, determine the end area 1 (A1) in ft².
Given
Find
end area 1 (A1), in ft²
Start with the thinking
- The governing relation printed in this handbook section is Average-end-area earthwork volume.
- Everything except A1 is given, so isolate A1 symbolically first — never rearrange after the numbers are in.
- Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
- Surveying items reward recognising the unknown before touching a calculator.
Step-by-step solution
Step 1 — State the governing relation:
Step 2 — Rearrange the relation so that A1 stands alone on the left-hand side.
Step 3
Step 4 — Substitute the given values into the rearranged relation.
Step 5 — Evaluate:
Step 6 — Check: returning A1 = 367.3 ft² to
reproduces the given quantities, and both sides carry the same units.
Why the other options are there
- 734.7 — kept a factor of two that cancels in the correct rearrangement.
- 183.7 — dropped that same factor in the other direction.
- 404.1 — rounded an intermediate value before the final step.
Reference: FE Reference Handbook — Surveying → Earthwork formulas