10 FE practice problems: material properties and concrete mix, with solutions
These ten original problems practice material properties and concrete mix, a topic from the FE Civil exam specification, using the Mechanics of Materials, Uniaxial Loading and Deformation part of the FE Reference Handbook 10.6. Each problem gives the situation and the values with units. Work it with the handbook PDF open and commit to an answer before you open the solution. Every solution shows the handbook page, the equation, the substitution with units, a size check, and the mistake behind each wrong option, so a wrong pick tells you exactly what to fix.
How to use these problems
Give each problem an honest attempt before you open the solution: write the given values with units, find the equation in the FE Reference Handbook PDF, and commit to an answer. Then compare line by line. If you picked a wrong option, read the note for that option; each one names the mistake that produces it.
The problems
Problem 1 · FE Civil, Material properties and concrete mix
In a tension test on a metal specimen with a diameter of 0.505 in. and a gauge length of 2 in., a load of 4 kips (within the elastic range) stretches the gauge length by 0.00399 in. The modulus of elasticity is most nearly:
Handbook: Mechanics of Materials, Uniaxial Loading and Deformation, FE Reference Handbook 10.6
Show the worked solution
- Answer
- A (10,000 ksi)
- Given
- d = 0.505 in., L0 = 2 in., P = 4 kips, dL = 0.00399 in., si =
- Find
- modulus of elasticity E (ksi)
- Handbook
- Mechanics of Materials, Uniaxial Loading and Deformation (σ = P/A, ε = δ/L, σ = Eε), page 131
- Equation
σ = P/A, ε = δ/L, E = σ/ε (Hooke's law)- Substitute
σ = P/A = 4 kips/[π(0.505 in.)²/4] = 19.97 ksiε = ΔL/L0 = 0.00399 in./2 in. = 0.001995E = σ/ε = 10,000 ksi
- Result
- 10,000 ksi, 3 significant figures
- Check
- 10,000 ksi is in the range of common structural metals; strain is a pure ratio.
- Why the others are wrong
- B: used d² for the area, leaving out π/4
- C: used πd² for the area (the diameter as if it were the radius)
- D: put the radius into πd²/4
Problem 2 · FE Civil, Material properties and concrete mix
A concrete batch uses 340 kg of cement, 155 kg of added water, and 640 kg of sand that carries 1.6% free water (by mass of sand, beyond saturated surface dry). The water-cement ratio is most nearly:
Handbook: Materials Science/Structure of Matter, Concrete, FE Reference Handbook 10.6
Show the worked solution
- Answer
- B (0.486)
- Given
- cement = 340 kg, water = 155 kg, sand = 640 kg, free = 1.6%
- Find
- water-cement ratio (by mass)
- Handbook
- Materials Science/Structure of Matter, Concrete (water-cement ratio), page 126
- Equation
w/c = total mixing water/cement (by mass)- Substitute
Free water from the sand = 640 kg × 1.6% = 10.24 kgTotal water = 155 + 10.24 = 165.2 kgw/c = 165.2/340 = 0.486
- Result
- 0.486, 3 significant figures
- Check
- a lower w/c gives higher strength (handbook figure); free water in the aggregate counts as mixing water.
- Why the others are wrong
- A: divided by cement plus sand
- C: left out the free water carried in by the sand
- D: subtracted the free water instead of adding it
Problem 3 · FE Civil, Material properties and concrete mix
In a tension test on a metal specimen with a diameter of 12.5 mm and a gauge length of 50 mm, a load of 11 kN (within the elastic range) stretches the gauge length by 0.0219 mm. The modulus of elasticity is most nearly:
Handbook: Mechanics of Materials, Uniaxial Loading and Deformation, FE Reference Handbook 10.6
Show the worked solution
- Answer
- D (205 GPa)
- Given
- d = 12.5 mm, L0 = 50 mm, P = 11 kN, dL = 0.0219 mm, si =
- Find
- modulus of elasticity E (GPa)
- Handbook
- Mechanics of Materials, Uniaxial Loading and Deformation (σ = P/A, ε = δ/L, σ = Eε), page 131
- Equation
σ = P/A, ε = δ/L, E = σ/ε (Hooke's law)- Substitute
σ = P/A = 11 kN/[π(12.5 mm)²/4] = 89.64 MPaε = ΔL/L0 = 0.0219 mm/50 mm = 0.0004380E = σ/ε = 205 GPa
- Result
- 205 GPa, 3 significant figures
- Check
- 205 GPa is in the range of common structural metals; strain is a pure ratio.
- Why the others are wrong
- A: used twice the gauge length in the strain
- B: used πd² for the area (the diameter as if it were the radius)
- C: used d² for the area, leaving out π/4
Problem 4 · FE Civil, Material properties and concrete mix
A concrete batch uses 355 kg of cement, 110 kg of added water, and 660 kg of sand that carries 5.0% free water (by mass of sand, beyond saturated surface dry). The water-cement ratio is most nearly:
Handbook: Materials Science/Structure of Matter, Concrete, FE Reference Handbook 10.6
Show the worked solution
- Answer
- D (0.403)
- Given
- cement = 355 kg, water = 110 kg, sand = 660 kg, free = 5.0%
- Find
- water-cement ratio (by mass)
- Handbook
- Materials Science/Structure of Matter, Concrete (water-cement ratio), page 126
- Equation
w/c = total mixing water/cement (by mass)- Substitute
Free water from the sand = 660 kg × 5.0% = 33.00 kgTotal water = 110 + 33.00 = 143.0 kgw/c = 143.0/355 = 0.403
- Result
- 0.403, 3 significant figures
- Check
- a lower w/c gives higher strength (handbook figure); free water in the aggregate counts as mixing water.
- Why the others are wrong
- A: used the free-water percentage as a fraction ten times too large
- B: left out the free water carried in by the sand
- C: subtracted the free water instead of adding it
Problem 5 · FE Civil, Material properties and concrete mix
A steel tension specimen has gauge marks 50 mm apart. After fracture, the pieces are fitted together and the marks are 58.51 mm apart. The percent elongation is most nearly:
Handbook: Mechanics of Materials, Uniaxial Stress-Strain, FE Reference Handbook 10.6
Show the worked solution
- Answer
- A (17.0%)
- Given
- L0 = 50 mm, Lf = 58.51 mm
- Find
- percent elongation (%)
- Handbook
- Mechanics of Materials, Uniaxial Stress-Strain (Percent Elongation), page 130
- Equation
% Elongation = (ΔL/L0) × 100- Substitute
% Elongation = (ΔL/L0) × 100 = (58.51 mm - 50 mm)/50 mm × 100 = 17.0%
- Result
- 17.0%, 3 significant figures
- Check
- percent elongation measures ductility; it uses the original gauge length.
- Why the others are wrong
- B: is the ratio of the lengths, not the change
- C: computed the true (logarithmic) strain instead of the engineering elongation
- D: divided by the final length instead of the original gauge length
Problem 6 · FE Civil, Material properties and concrete mix
In a tension test on a metal specimen with a diameter of 20 mm and a gauge length of 50 mm, a load of 36 kN (within the elastic range) stretches the gauge length by 0.0819 mm. The modulus of elasticity is most nearly:
Handbook: Mechanics of Materials, Uniaxial Loading and Deformation, FE Reference Handbook 10.6
Show the worked solution
- Answer
- B (70.0 GPa)
- Given
- d = 20 mm, L0 = 50 mm, P = 36 kN, dL = 0.0819 mm, si =
- Find
- modulus of elasticity E (GPa)
- Handbook
- Mechanics of Materials, Uniaxial Loading and Deformation (σ = P/A, ε = δ/L, σ = Eε), page 131
- Equation
σ = P/A, ε = δ/L, E = σ/ε (Hooke's law)- Substitute
σ = P/A = 36 kN/[π(20 mm)²/4] = 114.6 MPaε = ΔL/L0 = 0.0819 mm/50 mm = 0.001638E = σ/ε = 70.0 GPa
- Result
- 70.0 GPa, 3 significant figures
- Check
- 70.0 GPa is in the range of common structural metals; strain is a pure ratio.
- Why the others are wrong
- A: used πd² for the area (the diameter as if it were the radius)
- C: used twice the gauge length in the strain
- D: put the radius into πd²/4
Problem 7 · FE Civil, Material properties and concrete mix
In a tension test on a metal specimen with a diameter of 12.5 mm and a gauge length of 50 mm, a load of 29 kN (within the elastic range) stretches the gauge length by 0.1027 mm. The modulus of elasticity is most nearly:
Handbook: Mechanics of Materials, Uniaxial Loading and Deformation, FE Reference Handbook 10.6
Show the worked solution
- Answer
- A (115 GPa)
- Given
- d = 12.5 mm, L0 = 50 mm, P = 29 kN, dL = 0.1027 mm, si =
- Find
- modulus of elasticity E (GPa)
- Handbook
- Mechanics of Materials, Uniaxial Loading and Deformation (σ = P/A, ε = δ/L, σ = Eε), page 131
- Equation
σ = P/A, ε = δ/L, E = σ/ε (Hooke's law)- Substitute
σ = P/A = 29 kN/[π(12.5 mm)²/4] = 236.3 MPaε = ΔL/L0 = 0.1027 mm/50 mm = 0.002054E = σ/ε = 115 GPa
- Result
- 115 GPa, 3 significant figures
- Check
- 115 GPa is in the range of common structural metals; strain is a pure ratio.
- Why the others are wrong
- B: used twice the gauge length in the strain
- C: used d² for the area, leaving out π/4
- D: put the radius into πd²/4
Problem 8 · FE Civil, Material properties and concrete mix
A concrete batch uses 755 lb of cement, 325 lb of added water, and 1,290 lb of sand that carries 3.7% free water (by mass of sand, beyond saturated surface dry). The water-cement ratio is most nearly:
Handbook: Materials Science/Structure of Matter, Concrete, FE Reference Handbook 10.6
Show the worked solution
- Answer
- A (0.494)
- Given
- cement = 755 lb, water = 325 lb, sand = 1,290 lb, free = 3.7%
- Find
- water-cement ratio (by mass)
- Handbook
- Materials Science/Structure of Matter, Concrete (water-cement ratio), page 126
- Equation
w/c = total mixing water/cement (by mass)- Substitute
Free water from the sand = 1,290 lb × 3.7% = 47.73 lbTotal water = 325 + 47.73 = 372.7 lbw/c = 372.7/755 = 0.494
- Result
- 0.494, 3 significant figures
- Check
- a lower w/c gives higher strength (handbook figure); free water in the aggregate counts as mixing water.
- Why the others are wrong
- B: left out the free water carried in by the sand
- C: divided by cement plus sand
- D: used the free-water percentage as a fraction ten times too large
Problem 9 · FE Civil, Material properties and concrete mix
A steel tension specimen has gauge marks 2 in. apart. After fracture, the pieces are fitted together and the marks are 2.542 in. apart. The percent elongation is most nearly:
Handbook: Mechanics of Materials, Uniaxial Stress-Strain, FE Reference Handbook 10.6
Show the worked solution
- Answer
- D (27.1%)
- Given
- L0 = 2 in., Lf = 2.542 in.
- Find
- percent elongation (%)
- Handbook
- Mechanics of Materials, Uniaxial Stress-Strain (Percent Elongation), page 130
- Equation
% Elongation = (ΔL/L0) × 100- Substitute
% Elongation = (ΔL/L0) × 100 = (2.542 in. - 2 in.)/2 in. × 100 = 27.1%
- Result
- 27.1%, 3 significant figures
- Check
- percent elongation measures ductility; it uses the original gauge length.
- Why the others are wrong
- A: is the ratio of the lengths, not the change
- B: divided by the final length instead of the original gauge length
- C: computed the true (logarithmic) strain instead of the engineering elongation
Problem 10 · FE Civil, Material properties and concrete mix
A steel tension specimen has gauge marks 2 in. apart. After fracture, the pieces are fitted together and the marks are 2.198 in. apart. The percent elongation is most nearly:
Handbook: Mechanics of Materials, Uniaxial Stress-Strain, FE Reference Handbook 10.6
Show the worked solution
- Answer
- A (9.90%)
- Given
- L0 = 2 in., Lf = 2.198 in.
- Find
- percent elongation (%)
- Handbook
- Mechanics of Materials, Uniaxial Stress-Strain (Percent Elongation), page 130
- Equation
% Elongation = (ΔL/L0) × 100- Substitute
% Elongation = (ΔL/L0) × 100 = (2.198 in. - 2 in.)/2 in. × 100 = 9.90%
- Result
- 9.90%, 3 significant figures
- Check
- percent elongation measures ductility; it uses the original gauge length.
- Why the others are wrong
- B: computed the true (logarithmic) strain instead of the engineering elongation
- C: is the ratio of the lengths, not the change
- D: divided by the final length instead of the original gauge length
A new problem posts every day inside the lab, with the full worked solution the same evening.
Frequently asked questions
Where is material properties and concrete mix in the FE Reference Handbook?
Look in the Mechanics of Materials, Uniaxial Loading and Deformation part of FE Reference Handbook 10.6. Each solution gives the exact page, so you can practice finding it in the PDF the way you will on exam day.
Are these real FE exam questions?
No. They are original problems generated from the handbook formulas and checked by code. Real exam questions are confidential, and sharing them breaks the NCEES agreement every examinee accepts.
How do I check my answer before opening the solution?
Check the units of your result and whether its size makes sense for the situation. Each solution ends with the same kind of check, so you can compare your habit with ours.
Sources
- NCEES FE Civil CBT exam specifications (PDF). Retrieved October 3, 2026.
- NCEES FE Reference Handbook 10.6 (free PDF in MyNCEES). Retrieved October 3, 2026.