Castleport Test Prep

PE Civil Geotechnical Exam Prep

Start your PE Civil Geotechnical exam prep with 19 original worked problems covering all ten NCEES knowledge areas. These are unofficial practice, not real exam questions, and they can't predict a result.

Practice problems with worked solutions

GEO-01 · Rock core quality (RQD)

Area 1: Site Characterization · Multiple choice

A 1.50 m NX rock-core run recovers five sound pieces with centerline lengths of 0.42 m, 0.31 m, 0.28 m, 0.09 m, and 0.08 m. All breaks are natural (no drilling breaks to refit), and no other core is recovered. What is the rock quality designation (RQD), to the nearest 0.1%?

  • A. 67.3%
  • B. 78.7%
  • C. 85.6%
  • D. 100.0%
Show answer and explanation

Answer: A. 67.3%

RQD counts only sound pieces longer than 100 mm (about 4 in.), divided by the full length of the run. Three pieces qualify: (0.42 + 0.31 + 0.28) / 1.50 = 1.01 / 1.50 = 67.3%.

Why the others miss:

  • B: 78.7% is core recovery: every recovered piece (1.18 m) over the run. Recovery and RQD are different numbers.
  • C: 85.6% divides the qualifying length by the recovered length (1.18 m) instead of the run length.
  • D: Sound pieces are not the same as full-length pieces. Short pieces and lost core both pull RQD down.

Next task: Calculate core recovery for the same run (78.7%), then explain in one sentence why a drilling-induced break would be handled differently from a natural one.

Source: FHWA NHI-06-088, §§3.6.5.4–3.6.5.5, pp. 3-44–3-47 and Figs. 3-17–3-18

Work each problem before opening the answer. Keep a calculator and your copy of the free NCEES handbook nearby. Units switch between SI and U.S. customary on purpose, because the real exam uses both (NCEES handbook access; exam specifications).

The design standards supplied on the exam change in April 2027, so check the list for your exam date.

GEO-02 · USCS group symbol

Area 1: Site Characterization · Multiple choice

An inorganic soil sample has 62% passing the No. 200 sieve, a liquid limit (LL) of 45, and a plastic limit (PL) of 20. What is its Unified Soil Classification System (USCS) group symbol?

  • A. ML
  • B. CL
  • C. CH
  • D. SC
Show answer and explanation

Answer: B. CL

At least 50% passes the No. 200 sieve, so the soil is fine-grained. PI = LL − PL = 25. The A-line at LL = 45 is PI = 0.73(45 − 20) = 18.3. A PI of 25 plots above the A-line, and LL is below 50, so the symbol is CL (lean clay).

Why the others miss:

  • A: ML plots below the A-line. This soil plots above it.
  • C: CH requires LL of 50 or more.
  • D: SC is a coarse-grained symbol. With 62% fines this soil is fine-grained.

Next task: Change LL to 55 (keep PL = 20) and reclassify. Then find the plasticity chart in your reference so you can check the A-line without memorizing it.

Source: FHWA NHI-06-088, §4.2.1 and plasticity chart Fig. 4-3, p. 4-22

GEO-03 · Saturated unit weight from water content

Area 2: Soil Mechanics, Laboratory Testing, and Analysis · Multiple choice

A saturated clay sample has a water content of 32% and a specific gravity of solids of 2.70. Use γw = 62.4 lb/ft³. What is its saturated unit weight?

  • A. 90 lb/ft³
  • B. 119 lb/ft³
  • C. 143 lb/ft³
  • D. 57 lb/ft³
Show answer and explanation

Answer: B. 119 lb/ft³

Saturated means S = 1, so Se = wGs gives e = (0.32)(2.70) = 0.864. Then γsat = (Gs + e)γw / (1 + e) = (3.564)(62.4) / 1.864 = 119.3 lb/ft³.

Why the others miss:

  • A: 90.4 lb/ft³ is the dry unit weight, Gsγw/(1 + e). It leaves out the water.
  • C: This plugs w in where e belongs: (2.70 + 0.32)(62.4)/1.32.
  • D: 57 lb/ft³ is the buoyant unit weight, γsat − γw.

Next task: From the same data, compute dry and buoyant unit weight and porosity. Explain why soil above the water table is not automatically dry, and when buoyant unit weight can be used to calculate the submerged layer's contribution to effective stress.

Source: FHWA NHI-06-088, §2.1, Table 2-2, p. 2-8; §§2.2–2.3, pp. 2-19–2-21

GEO-04 · Effective stress below a water table

Area 2: Soil Mechanics, Laboratory Testing, and Analysis · Multiple choice

Level ground has a water table 1.5 m below the surface. Soil above it weighs 18.0 kN/m³; saturated soil below weighs 20.0 kN/m³. A long-standing surface surcharge adds 15.0 kPa to vertical total stress at the point of interest. Assume hydrostatic groundwater, no excess pore pressure, and no capillary effect. Use γw = 9.81 kN/m³. What is the vertical effective stress 5.5 m below the ground surface?

  • A. 39.2 kPa
  • B. 68.0 kPa
  • C. 82.8 kPa
  • D. 122.0 kPa
Show answer and explanation

Answer: C. 82.8 kPa

Total stress: σ = 1.5(18.0) + 4.0(20.0) + 15.0 = 122.0 kPa. Pore pressure acts only below the water table: u = 4.0(9.81) = 39.24 kPa. Effective stress: σ′ = σ − u = 82.8 kPa.

Why the others miss:

  • A: 39.2 kPa is the pore pressure alone.
  • B: This uses 5.5 m of water head instead of the 4.0 m below the water table.
  • D: 122.0 kPa is total stress. Pore pressure still has to come off.

Next task: Make three columns (σ, u, σ′) and redo the profile without the surcharge. You should get 67.8 kPa.

Source: FHWA NHI-06-088, §2.2, Eq. 2-13, p. 2-19

GEO-05 · Constant-head permeability test

Area 2: Soil Mechanics, Laboratory Testing, and Analysis · Multiple choice

A steady constant-head test on a saturated sand specimen 10 cm in diameter and 15 cm long runs under a 60 cm head difference. It collects 450 cm³ of water in 300 s. Assume laminar flow. What is the hydraulic conductivity?

  • A. 1.2 × 10⁻³ cm/s
  • B. 4.8 × 10⁻³ cm/s
  • C. 1.4 cm/s
  • D. 4.8 × 10⁻¹ cm/s
Show answer and explanation

Answer: B. 4.8 × 10⁻³ cm/s

k = QL / (A h t). Area A = π(10)²/4 = 78.5 cm². k = (450)(15) / [(78.5)(60)(300)] = 4.8 × 10⁻³ cm/s.

Why the others miss:

  • A: This uses πD² for the area and forgets to divide by 4, so the area is four times too big.
  • C: This leaves out time. Q here is a volume, so divide by t.
  • D: Right digits, wrong power of ten. Carry the exponent through each step.

Next task: Rework it with the head doubled to 120 cm and the volume doubled. Predict the answer before calculating.

Source: FHWA NHI-06-088, §§5.6.2–5.6.3, pp. 5-58–5-61; EPA, Darcy's Law Calculation (k = volume × length / area / head / time is derived from Darcy flux)

GEO-06 · OSHA excavation slope

Area 3: Construction Observation, Monitoring, and Quality Assurance/Quality Control and Safety · Multiple choice

A 14 ft deep excavation is cut in unfissured clay with an unconfined compressive strength of 1.8 tsf. It runs beside a highway with heavy truck traffic that sends vibration into the soil. A competent person has found no submerged soil, freely seeping water, adverse layering, or other Type C condition. Under 29 CFR 1926 Subpart P, what is the maximum allowable simple slope from Table B-1?

  • A. ½H:1V
  • B. ¾H:1V
  • C. 1H:1V
  • D. 1½H:1V
Show answer and explanation

Answer: C. 1H:1V

By strength alone, 1.8 tsf would be Type A (1.5 tsf or more). But Appendix A says no soil is Type A if it is subject to vibration from heavy traffic. The soil drops to Type B, and Table B-1 gives Type B a maximum allowable slope of 1H:1V for excavations under 20 ft. Traffic is also a surcharge, so Appendix B tells the competent person to determine how much flatter the actual slope must be than that maximum and ensure that reduction is achieved.

Why the others miss:

  • A: ½H:1V is the Type A short-term slope, and only for excavations 12 ft deep or less. This one is 14 ft and is not Type A.
  • B: ¾H:1V is Type A. Vibration rules out Type A.
  • D: 1½H:1V is Type C. Nothing in the stem makes this soil Type C.

Next task: Find Table B-1 in Appendix B and the Type A exclusions in Appendix A. Note the depth at which sloping must be designed by a registered professional engineer (more than 20 ft).

Source: 29 CFR 1926 Subpart P, App. A(b) soil type definitions; 29 CFR 1926 Subpart P, App. B, Table B-1 and (c)(3)(iii)

GEO-07 · Relative compaction

Area 3: Construction Observation, Monitoring, and Quality Assurance/Quality Control and Safety · Numeric entry

A corrected field test gives a total (wet) unit weight of 136.0 lb/ft³ at a water content of 16.0%. The specified laboratory compaction test for the same material gives a maximum dry unit weight of 120.0 lb/ft³. What is the relative compaction, in percent, to the nearest 0.1%?

Give your answer in %.

Show answer and explanation

Answer: 97.7%

Compare dry with dry. Field dry unit weight = 136.0 / (1 + 0.160) = 117.24 lb/ft³. Relative compaction = 117.24 / 120.0 = 97.7%.

Common wrong entries:

  • 113.3: 136/120 compares a wet unit weight with a dry one. That is not relative compaction.
  • Entering 16 for w: Water content goes in as a decimal (0.160), not 16.

Next task: Write the comparison entirely in dry unit weights. Then list what a real specification would also need (test method, moisture window) before you could accept the lift.

Source: FHWA NHI-06-088, §2.1.2–2.1.3 and §5.8.3, Eq. 5-19, pp. 5-76–5-77

GEO-08 · Cyclic stress ratio for liquefaction

Area 4: Earthquake Engineering and Dynamic Loads · Multiple choice

At 20 ft depth in saturated sand, initial total vertical stress is 2,300 psf and initial effective vertical stress is 1,550 psf. Peak horizontal ground surface acceleration is 0.30g. Use a stress reduction coefficient rd = 0.96. Using the simplified procedure, what is the cyclic stress ratio (CSR)?

  • A. 0.13
  • B. 0.19
  • C. 0.28
  • D. 0.43
Show answer and explanation

Answer: C. 0.28

CSR = 0.65 (amax/g)(σv/σ′v) rd = 0.65(0.30)(2,300/1,550)(0.96) = 0.28.

Why the others miss:

  • A: This flips the stress ratio (1,550/2,300).
  • B: This drops the σv/σ′v ratio entirely.
  • D: This leaves out the 0.65 factor.

Next task: Find the simplified-procedure equation and the rd curves in your seismic reference. Then note what CSR is compared against to judge liquefaction (the soil's cyclic resistance).

Source: FHWA GEC No. 3 (FHWA-NHI-11-032), §6.3.4, Eq. 6-16 and Fig. 6-18, p. 6-36

GEO-09 · Infinite slope in dry sand

Area 5: Earth Structures, Ground Improvement, and Pavement · Multiple choice

A long slope in dry, cohesionless sand with φ′ = 34° is graded at 2H:1V. Treating it as an infinite slope, what is the factor of safety against shallow sliding?

  • A. 0.34
  • B. 0.74
  • C. 1.35
  • D. 2.70
Show answer and explanation

Answer: C. 1.35

For a dry cohesionless infinite slope, FS = tan φ′ / tan β. A 2H:1V slope has tan β = 1/2 = 0.50. tan 34° = 0.675. FS = 0.675 / 0.50 = 1.35.

Why the others miss:

  • A: This reads 2H:1V upside down (tan β = 2).
  • B: This inverts the ratio.
  • D: This is double the right answer, usually from dividing by 0.5 twice.

Next task: Rework it for a 1.5H:1V slope. Then find the version with seepage parallel to the slope and explain why water lowers FS.

Source: FHWA NHI-06-088, §6.3.1, Eq. 6-5, pp. 6-5–6-6; §6.3.2, Eq. 6-10, p. 6-8

GEO-10 · Drainage path and consolidation time

Area 5: Earth Structures, Ground Improvement, and Pavement · Multiple choice

A 6.0 m thick saturated clay layer under a wide embankment drains only at the top (the base is impervious). Estimated time to 90% average primary consolidation is 480 days. In a comparison case, the layer drains at both top and bottom. Thickness, loading, uniform initial excess pore pressure, and coefficient of consolidation are unchanged. What is the time to 90% consolidation in the comparison case?

  • A. 120 days
  • B. 240 days
  • C. 480 days
  • D. 1,920 days
Show answer and explanation

Answer: A. 120 days

t = Tv Hd² / cv. For the same degree of consolidation and cv, time scales with the longest drainage path squared. Hd drops from 6.0 m to 3.0 m: t = 480 (3/6)² = 120 days.

Why the others miss:

  • B: Halving the time misses the square.
  • C: The drainage boundary changed, so time changes.
  • D: This flips the ratio (doubles the path).

Next task: Sketch the longest drainage path for each case. Then predict what happens if a one-way path doubles (time goes up four times).

Source: FHWA NHI-06-088, §7.5.3.1, Eq. 7-8, p. 7-31 and Table 7-4, p. 7-32

GEO-11 · Darcy discharge

Area 6: Groundwater and Seepage · Numeric entry

Steady one-dimensional flow passes through a homogeneous saturated soil. Hydraulic conductivity is 4.0 × 10⁻⁵ m/s. Total head drops 2.0 m over a 10.0 m flow path. The gross area normal to flow is 3.0 m². What is the discharge in L/s, to the nearest 0.001 L/s?

Give your answer in L/s.

Show answer and explanation

Answer: 0.024 L/s

Gradient i = 2.0/10.0 = 0.20. Darcy flux = Ki = 8.0 × 10⁻⁶ m/s. Q = KiA = 2.4 × 10⁻⁵ m³/s = 0.024 L/s (1 m³ = 1,000 L).

Common wrong entries:

  • 0.24: This skips dividing the head loss by the flow length.
  • 0.000024: This is the answer in m³/s, not converted to litres.

Next task: Write the output units before you calculate. Then explain the difference between Darcy flux and the actual pore-water (seepage) velocity.

Source: EPA, Darcy's Law Calculation (q = −Ki and units)

GEO-12 · What frost heave needs

Area 7: Problematic Soil and Rock Conditions · Select all that apply

FHWA identifies three conditions that must all be present for frost heave and related frost-action problems. Select all three.

  • A. Frost-susceptible soil
  • B. Subfreezing temperatures in the soil
  • C. A source of water
  • D. Repeated heavy truck loading
  • E. Peat in the subgrade
Show answer and explanation

Answer: A, B, and C

Frost heave needs frost-susceptible soil, subfreezing temperatures in the soil, and a water source, all at once. Remove any one and the mechanism stops. Silts are the classic problem soil: small voids, strong capillary rise, and enough permeability to feed growing ice lenses. FHWA places all silts in its highest frost-susceptibility group (F4); clean, free-draining sands and gravels show little to no frost action under normal freezing conditions.

Why the others miss:

  • D: Traffic can make frost damage worse, but heave happens without it.
  • E: Peat is not a requirement. Silts are the textbook frost-susceptible soil.

Next task: Find FHWA's frost-susceptibility table (F1 to F4). Then explain why a cold air-temperature record alone doesn't prove the soil itself froze.

Source: FHWA NHI-05-037, Ch. 7, §7.5.6 and Table 7-12

GEO-13 · Rankine active thrust and location

Area 8: Retaining Structures (ASD or LRFD) · Multiple choice

A wall with a smooth vertical back retains 15 ft of level, dry, cohesionless backfill: γ = 120 lb/ft³, φ′ = 32°. The wall moves enough to reach the active state. There is no surcharge or water. Using Rankine theory, what are the active resultant per foot of wall and its height above the base?

  • A. 4.1 kips/ft at 5.0 ft
  • B. 4.1 kips/ft at 7.5 ft
  • C. 6.3 kips/ft at 5.0 ft
  • D. 8.3 kips/ft at 5.0 ft
Show answer and explanation

Answer: A. 4.1 kips/ft at 5.0 ft

Ka = tan²(45° − φ′/2) = tan²(29°) ≈ 0.3073. Pressure grows linearly from zero to KaγH at the base, so Pa = ½KaγH² = 0.5 × tan²(29°) × 120 × 15² ≈ 4,148 lb/ft ≈ 4.1 kips/ft. A triangle's resultant acts at H/3 = 5.0 ft above the base.

Why the others miss:

  • B: Mid-height would be right for a uniform (rectangular) pressure, not a triangle.
  • C: This uses the at-rest estimate K0 = 1 − sin φ′ = 0.47 for normally consolidated soil. The wall reached the active state.
  • D: This forgets the ½ for the triangle.

Next task: Draw the pressure diagram with the base pressure (KaγH = 553 psf) labeled separately from the resultant. Then add a uniform 250 psf surcharge and find the new resultant and its location.

Source: FHWA NHI-06-088, §2.9 and §2.9.1, pp. 2-42 to 2-46; FHWA NHI-06-089, §10.2.1, Eq. 10-2, p. 10-10; §10.4.2, Eq. 10-14, p. 10-31

GEO-14 · What raises the lateral force on a wall

Area 8: Retaining Structures (ASD or LRFD) · Select all that apply

A cantilever wall retains granular backfill with Ka of about 0.3. Assume a smooth vertical wall, level backfill, active Rankine conditions, no water in front of the wall, and all other properties and loads held fixed. Considering each change on its own, which ones increase the total lateral force on the wall? Select all that apply.

  • A. Groundwater rises into the backfill and the wall has no drainage
  • B. The backfill is replaced with a material that has a higher friction angle
  • C. A uniform surcharge is placed on the backfill surface
  • D. The retained height increases
  • E. The backfill unit weight decreases
Show answer and explanation

Answer: A, C, and D

A: below the water table the earth pressure uses the lower buoyant unit weight, but full water pressure (coefficient 1.0) is added on top. With Ka near 0.3, the total jumps. This is why walls get drains. C: a surcharge q adds Ka·q over the full height. D: thrust grows with H², so height matters a lot.

Why the others miss:

  • B: A higher friction angle lowers Ka and the thrust.
  • E: Lighter backfill lowers the pressure directly.

Next task: For GEO-13's wall, put the water table at mid-height and recompute the total force with separate soil and water diagrams. Use γsat = 130 lb/ft³, γw = 62.4 lb/ft³, hydrostatic water pressure, and no capillary effect; keep the original dry unit weight above the water table.

Source: FHWA NHI-06-088, §2.9.1, Fig. 2-22, p. 2-46; FHWA NHI-06-089, §10.4.2, Eq. 10-14, p. 10-31

GEO-15 · Bearing capacity on clay (φ = 0)

Area 9: Shallow Foundations (ASD or LRFD) · Multiple choice

A 4 ft wide strip footing sits 3 ft deep in saturated clay with undrained shear strength su = 1,200 psf (φ = 0). Soil unit weight is 118 lb/ft³ and groundwater is deep. Assume a rigid footing with a rough, horizontal base, a centered vertical load, level ground, and homogeneous soil. Use Nc = 5.14, Nq = 1.0, Nγ = 0, unity correction factors, and a factor of safety of 3 on the gross ultimate value. What is the gross allowable bearing pressure?

  • A. 2,060 psf
  • B. 2,170 psf
  • C. 2,400 psf
  • D. 6,520 psf
Show answer and explanation

Answer: B. 2,170 psf

qult = cNc + qNq + ½γBNγ = 1,200(5.14) + (3)(118)(1.0) + 0 = 6,168 + 354 = 6,522 psf. Gross allowable = 6,522 / 3 = 2,174 psf.

Why the others miss:

  • A: This drops the overburden term qNq.
  • C: This swaps in Nc = 5.7 instead of the factor the problem gave you.
  • D: This is the ultimate value. The factor of safety still has to be applied.

Next task: Find the bearing capacity factor table in your reference. Then rework it as a square footing using the shape factors in FHWA NHI-06-089 Table 8-4 (sc = 1.2, sq = sγ = 1.0 for φ = 0), keeping the other correction factors at 1.0.

Source: FHWA NHI-06-089, §8.4.2, Eq. 8-1, p. 8-18; Table 8-2, p. 8-20; Table 8-4, p. 8-27; FHWA GEC No. 6, Ch. 5, pp. 47, 51–53

GEO-16 · Consolidation settlement of normally consolidated clay

Area 9: Shallow Foundations (ASD or LRFD) · Multiple choice

A 10 ft thick normally consolidated clay layer has e0 = 1.10 and Cc = 0.36. At mid-layer, initial effective stress is 1,200 psf and a new footing adds 900 psf. Use a one-dimensional, single-layer approximation with these mid-layer stresses representing the full thickness. What is the primary consolidation settlement?

  • A. 5.0 in.
  • B. 7.6 in.
  • C. 10.5 in.
  • D. 11.5 in.
Show answer and explanation

Answer: A. 5.0 in.

S = [Cc H / (1 + e0)] log(σ′f / σ′0) = [0.36(120 in.) / 2.10] log(2,100 / 1,200) = 20.57 × 0.243 = 5.0 in.

Why the others miss:

  • B: This divides by the stress increase (900) inside the log instead of the initial stress.
  • C: This leaves out (1 + e0).
  • D: This uses the natural log. The equation uses log base 10.

Next task: Rework it as overconsolidated with a preconsolidation pressure of 1,800 psf and Cr = 0.06. Decide first which equation applies.

Source: FHWA NHI-06-088, §7.5.2.1, Eq. 7-2, p. 7-24; §7.5.2.2, Eq. 7-4, p. 7-26

GEO-17 · A footing must pass two checks

Area 9: Shallow Foundations (ASD or LRFD) · Multiple choice

For one trial footing, gross service contact pressure is 200 kPa. The gross allowable pressure against shear failure, with its factor of safety already applied, is 250 kPa. A separate settlement analysis gives a gross pressure limit of 180 kPa for the same footing. Which conclusion is correct?

  • A. Both requirements are satisfied.
  • B. Shear is satisfied; settlement is not.
  • C. Settlement is satisfied; shear is not.
  • D. Neither is satisfied.
Show answer and explanation

Answer: B. Shear is satisfied; settlement is not.

200 kPa is below the 250 kPa shear limit but above the 180 kPa settlement limit. The lower limit controls, so settlement governs and fails. Don't average the two limits, and don't apply a second factor of safety to a value that is already allowable.

Why the others miss:

  • A: Overlooks the settlement limit.
  • C: Reverses both comparisons.
  • D: Overlooks the shear margin.

Next task: Write the two checks as separate lines on the same pressure basis. Then name two ways to bring the footing within the settlement limit.

Source: FHWA GEC No. 6 (FHWA-SA-02-054), Ch. 5, §5.1, p. 47; FHWA NHI-06-089, §8.4 and §8.5

GEO-18 · Pile in clay by the α-method

Area 10: Deep Foundations (ASD or LRFD) · Multiple choice

A 16 in. diameter closed-end steel pipe pile is driven 50 ft into uniform clay with su = 1,000 psf. Use α = 0.80 for side resistance and unit tip resistance qp = 9su. Assume the given side and tip resistances can be mobilized together; ignore pile self-weight, downdrag, group effects, and structural limits. What is the nominal (ultimate) axial geotechnical compression capacity?

  • A. 60 kips
  • B. 168 kips
  • C. 180 kips
  • D. 222 kips
Show answer and explanation

Answer: C. 180 kips

Side: Qs = α su (πD) L = 0.80(1,000)(π × (16/12) ft)(50 ft) ≈ 167.6 kips. Tip (closed end, full area): Qp = 9(1,000)(π × (16/12)²/4) ≈ 12.6 kips. Total ≈ 180 kips.

Why the others miss:

  • A: 60 kips is 180 divided by 3, an allowable value if a factor of safety of 3 were specified. The question asks for nominal capacity.
  • B: This leaves out the tip.
  • D: This leaves out α, so it assumes full adhesion.

Next task: Before reworking it for an open-end pipe, list what you would need to know about plugging. Then state which checks (structural, settlement, group) this number does not cover.

Source: FHWA NHI-06-089, §9.4, Eqs. 9-1–9-2, p. 9-22; §9.5.2.1, Eqs. 9-8–9-11, pp. 9-47, 9-51–9-52

GEO-19 · Square pile: side plus tip

Area 10: Deep Foundations (ASD or LRFD) · Multiple choice

An isolated square pile is 0.30 m on each side with 12.0 m embedded. Average unit side resistance over the full embedded perimeter is 25 kPa, and unit tip resistance is 1,000 kPa over the gross tip area. Assume both can be mobilized together and ignore self-weight, downdrag, group effects, and structural limits. What is the nominal axial geotechnical resistance in compression?

  • A. 90 kN
  • B. 180 kN
  • C. 360 kN
  • D. 450 kN
Show answer and explanation

Answer: D. 450 kN

Side area = perimeter × length = (4 × 0.30)(12.0) = 14.4 m², so side resistance = 25 × 14.4 = 360 kN. Tip area = 0.30² = 0.09 m², so tip resistance = 1,000 × 0.09 = 90 kN. Total = 450 kN.

Why the others miss:

  • A: Tip only.
  • B: Uses one face for the side area, then adds the tip.
  • C: Side only.

Next task: Sketch the four faces and the tip. Label the answer nominal and unfactored, then list the checks the stem deliberately left out.

Source: FHWA NHI-06-089, §9.4, Eqs. 9-1–9-2, p. 9-22

Tally your results

Count your correct answers by area. On 19 problems, a single miss can swing an area from "fine" to "weak," so treat the tally as a list of things to look at, not a score. It is not a scaled score and says nothing about whether you'd pass.

Use your misses to pick the next task

What went wrong matters more than how many you got right. A wrong method needs a fresh explanation and a new example. A unit slip needs a redo with units written at every step. A slow lookup needs a reference drill.

Use your misses to pick the next task
What happenedDo this nextWrite this down
I didn't know which method to useReread the worked solution, list its assumptions, then set up a similar problem before calculatingThe method and the clue in the problem that points to it
I knew the method but couldn't find itDo the matching reference drill belowDocument, section, and the search word that worked
I used the wrong layer, water level, or loadRedraw the problem and mark exactly what is being askedThe misread detail and a corrected sketch
I mixed units or slipped on arithmeticRedo it with units on every line and sanity-check the size of the answerThe specific conversion or keying error
I got it right but guessedExplain why each wrong option fails, then try another exampleThe decision you couldn't justify

Error log

Copy these columns into a notebook or spreadsheet. Log a repeat attempt as a new row, because solving a problem you've already seen isn't fresh evidence.

Error log
DateProblem / sourceAreaMy answerCauseCorrect method and where it livesNext taskRecheck
(example)GEO-042122.0 kPaReported total stress as effective stressσ′ = σ − u; FHWA NHI-06-088 §2.2, p. 2-19Redo without the surcharge using only the 4.0 m of water head67.8 kPa on rework

Coverage tracker

Copy this tracker beside your error log. Use the named areas in the topic table below to choose a next subtopic. The starter problems touch every area, but they do not cover every subtopic.

Coverage tracker
AreaStarter problemsNext subtopic to studyReference / sectionRecheck date and result
1 · Site CharacterizationGEO-01, GEO-02
2 · Soil Mechanics, Laboratory Testing, and AnalysisGEO-03–GEO-05
3 · Construction Observation, Monitoring, and Quality Assurance/Quality Control and SafetyGEO-06, GEO-07
4 · Earthquake Engineering and Dynamic LoadsGEO-08
5 · Earth Structures, Ground Improvement, and PavementGEO-09, GEO-10
6 · Groundwater and SeepageGEO-11
7 · Problematic Soil and Rock ConditionsGEO-12
8 · Retaining Structures (ASD or LRFD)GEO-13, GEO-14
9 · Shallow Foundations (ASD or LRFD)GEO-15–GEO-17
10 · Deep Foundations (ASD or LRFD)GEO-18, GEO-19

What's on the exam: the ten knowledge areas

The PE Civil: Geotechnical exam has 80 questions spread across ten knowledge areas. NCEES publishes a range for each one (exam specifications, pp. 1–3). The same ten areas and ranges appear in the document NCEES posted for April 2027 (2027 document, pp. 1–3). ASD means allowable stress design; LRFD means load and resistance factor design.

What's on the exam: the ten knowledge areas
No.Knowledge areaQuestionsPractice this next
1Site Characterization8–12Read a boring log and subsurface profile. Know which data comes from sampling, which from in situ tests (SPT, CPT, vane, pressuremeter), and which from the lab. Classify soils (USCS, AASHTO) and rock (RQD, rock mass rating).
2Soil Mechanics, Laboratory Testing, and Analysis8–12Phase relations, total vs. effective stress, strength, and permeability. Before picking an equation, say whether the case is drained or undrained.
3Construction Observation, Monitoring, and Quality Assurance/Quality Control and Safety6–9Compaction calculations, matching an instrument (inclinometer, piezometer, settlement plate) to what it measures, and finding the OSHA excavation rules.
4Earthquake Engineering and Dynamic Loads5–8Keep site characterization, liquefaction, and seismic earth pressure separate. Know where the seismic procedures live in the supplied references.
5Earth Structures, Ground Improvement, and Pavement9–14Slope stability, embankment settlement and its timing, ground improvement, geosynthetics, landfills, pavements, and utilities. Track these as separate subtopics; the area is wide.
6Groundwater and Seepage4–6Sketch heads and drainage boundaries first. Keep discharge, Darcy flux, and seepage velocity distinct. Add dewatering and seepage control.
7Problematic Soil and Rock Conditions4–6Karst, collapsible, expansive, organic, and sensitive soils; corrosivity; frost; rock slopes. For each, know what you'd investigate and how you'd treat it.
8Retaining Structures (ASD or LRFD)10–15Pick the pressure state (active, at-rest, passive) before calculating. Separate soil, surcharge, and water forces. Cover gravity, cantilever, sheet pile, braced, anchored, soil nail, and MSE external stability.
9Shallow Foundations (ASD or LRFD)6–9Bearing capacity, stress distribution under footings, and settlement. Keep net vs. gross pressure consistent.
10Deep Foundations (ASD or LRFD)10–15Side and tip resistance, settlement, lateral response, installation, and load and integrity testing for driven piles, drilled shafts, and micropiles.

The published minimum counts for areas 8, 9, and 10 add up to 26 questions. That's a good reason to give them steady time, but it doesn't tell you how hard they are for you. Your misses should drive the calendar more than the ranges do. NCEES also notes that the examples it lists under each area aren't exhaustive.

Design standards for your exam date

NCEES supplies the PE Civil Reference Handbook plus a specific list of design standards on screen during the exam, and those are the only references you get. You can't bring your own copies (NCEES PE Civil page). Answers that depend on a standard are scored against the edition on NCEES's list, so studying from a different edition can cost you points (spec, design standards pages).

The list changes for exams beginning April 2027. The knowledge areas and question ranges stay the same.

Design standards for your exam date
Design standardExams before April 2027Exams beginning April 2027
ASCE 7, Minimum Design Loads for Buildings and Other StructuresASCE 7-16 (2017)ASCE 7 (2022)
USACE EM 1110-2-1902, Slope Stability (2003)ListedListed
FHWA NHI-05-037, Geotechnical Aspects of Pavements (2006)ListedListed
FHWA NHI-06-088 and NHI-06-089, Soils and Foundations Vol. I and II (2006)ListedListed
FHWA-NHI-07-092, Geosynthetic Design & Construction Guidelines (August 2008)Not listedAdded
FHWA-NHI-11-032, GEC No. 3, LRFD Seismic Analysis and Design (2011)ListedListed
FHWA NHI-16-009 and NHI-16-010, GEC No. 12, Driven Pile Foundations Vol. I and II (2016)ListedListed
FHWA NHI-16-072, GEC No. 5, Geotechnical Site Characterization (2017)ListedListed
FHWA NHI-18-024, GEC No. 10, Drilled Shafts (2018)ListedListed
NAVFAC DM-7.02, Foundations & Earth Structures (1986)ListedRemoved
29 CFR Part 1926 (Subparts E, M, P, and CC only)July 2020 edition2024 edition
UFC 3-220-05, Dewatering and Groundwater Control (2004)ListedListed
UFC 3-220-10, Soil Mechanics (2022)ListedListed
UFC 3-220-20, Foundations and Earth Structures (2025)Not listedAdded

Official lists: Before April 2027 (PDF) · Beginning April 2027 (PDF). NCEES posts new specifications and standards six months before they take effect (NCEES). If your appointment falls near the switch, open the list that matches your exam date and compare it with the table above.

Where to look first

This routes each topic to the supplied document whose title and scope fit it best. It's a starting point for your searches, not a promise that every answer sits in that one document.

Where to look first
TopicLook first in
Exploration, sampling, in situ testing, rock coreGEC No. 5 (NHI-16-072); NHI-06-088
Index properties, effective stress, consolidation, basic slope stabilityNHI-06-088; UFC 3-220-10
Bearing capacity, settlement of footings, pile capacity basicsNHI-06-089
Slope stability methodsUSACE EM 1110-2-1902
Trench and excavation safety29 CFR 1926 Subpart P
Liquefaction and seismic geotechnical designGEC No. 3 (NHI-11-032)
Seismic loadsASCE 7 (edition for your date)
Pavements and frostNHI-05-037
Driven pilesGEC No. 12
Drilled shaftsGEC No. 10
DewateringUFC 3-220-05
Geosynthetics and MSE internal stabilityNHI-07-092 (April 2027 list only)
Foundations and earth structures design-manual materialNAVFAC DM-7.02 before April 2027; UFC 3-220-20 from April 2027
Everything elsePE Civil Reference Handbook

How the references work on screen

  • The handbook and standards are searchable PDFs. Use the search box on the left side of the reference window. Ctrl+F does not work (Examinee Guide, p. 10).
  • Standards are split into chapters, and only one chapter can be open and searched at a time (spec, design standards pages).
  • Download the current handbook free from your MyNCEES account. NCEES doesn't sell printed handbooks or provide study copies of the standards (NCEES).
  • Several supplied references are free government documents. The FHWA manuals and the OSHA rules linked on this page are good places to start practicing your searches.

Reference-finding drills

Searching fast is a skill, and it only improves with practice. For each drill, find the passage yourself first and log document → section → search word that worked → when the method applies. Then check the answer.

Reference-finding drills
DrillFind thisWhere it isWhat you should come away with
REF-01How RQD is measuredNHI-06-088 §3.6.5.5, p. 3-44Sound pieces longer than 100 mm (about 4 in.), over the full run length
REF-02The effective stress relationNHI-06-088 §2.2, p. 2-19σ′ = σ − u; for hydrostatic water without capillary effects, u = γw × depth below the water table
REF-03Relative compactionNHI-06-088 §5.8.3, Eq. 5-19Field dry unit weight over laboratory maximum dry unit weight
REF-04Drainage distance in consolidation timeNHI-06-088 §7.5.3.1, Eq. 7-8, p. 7-31Time scales with the longest drainage path squared
REF-05The three conditions for frost heaveNHI-05-037 §7.5.6Frost-susceptible soil, subfreezing soil temperature, and water, all together
REF-06Maximum allowable excavation slopes29 CFR 1926 Subpart P, App. B, Table B-1Stable rock vertical; Type A ¾:1; Type B 1:1; Type C 1½:1 (under 20 ft)

When those feel easy, build your own drills for the documents you haven't opened yet, especially GEC No. 10, GEC No. 12, and your edition of ASCE 7. Your notes can't come into the exam room, but the habit of knowing where things live does.

Your 12-week study plan

Time assumption: 8 hours a week (6 hours of topic study and problems, 1 hour of reference practice, 1 hour reworking misses). That's 96 planned hours. This is our editorial plan for you to adapt. NCEES doesn't set a required study time, and no schedule guarantees a result.

Your 12-week study plan
WeekTopic block (6 hr)AreasFinish the week with
1Baseline: match your exam date to the standards list, download the handbook, work the 19 problems above cold, and skim each supplied standard's table of contentsAllAn error log, a coverage tracker for all ten areas, and your first next tasks
2Phase relations, effective stress, shear strength, permeability, lab tests2Checked calculations with units, plus a note on what each lab test measures
3Exploration planning, sampling, SPT/CPT and other in situ tests, soil and rock classification1An annotated boring log and a classification worked from lab data
4Bearing capacity, stress under footings, settlement9One shallow foundation case checked for both shear and settlement
5Earth pressure theory; gravity, cantilever, and MSE external stability8Labeled pressure diagrams with soil, surcharge, and water separated
6Sheet pile, braced, and anchored walls; tiebacks, soil nails, cofferdams, underpinning8A worked flexible-wall problem with its embedment or anchor check
7Axial capacity of driven piles and drilled shafts; pile settlement10Checked side-plus-tip calculations in clay and sand
8Lateral capacity, installation, load and integrity testing; then slope stability10, 5A list of what a capacity number does and doesn't cover, plus a slope FS problem
9Ground improvement, geosynthetics, embankments, landfills, pavements, utilities5A comparison of improvement methods by purpose and how each is verified
10Liquefaction and seismic loads; seepage and dewatering; problematic soils4, 6, 7A CSR calculation, a seepage solution, and a soil-problem-to-investigation table
11Earthwork, compaction, instrumentation, OSHA excavation rules; then timed mixed problems from the set above3, AllTiming notes and a fresh error log from the timed attempt
12Close the gaps: rework misses from weeks 1–11, run timed mixed blocks, and recheck your standards list and exam-day rulesWeakest areasAn unresolved-topics list, a final standards-edition check, and a light last two days

If you have an authorized full-length practice exam, schedule the attempt, its break, and review outside the 96-hour study budget. The 19 problems above are a starter set, and repeating them is practice, not a fresh full-length simulation.

Use the two fixed hours every week of the 12-week plan:

  • Reference hour: find the documents and sections behind that week's topic and log the search words that worked.
  • Rework hour: redo an earlier miss before looking at its answer. Note whether the cause was the method, reference, data, units, arithmetic, interpretation, or time.

Adjust the plan

Adjust the plan
Your situationChange this
Rusty after years awayStretch weeks 2–3 to two weeks each if the fundamentals feel shaky. Keep every later area on the calendar.
Retaking the examUse your NCEES diagnostic report to reorder the weeks. Start with areas well below passing examinees that also carry many questions, and keep all ten areas in rotation.
Only 4 hours a weekSpread each row over two weeks: 3 hours of topic work, 30 minutes of reference practice, and 30 minutes of rework each week—24 weeks, the same 96 hours.
Less time before your dateMerge weeks 2–3, 5–6, 7–8, and 9–10 for an 8-week version: allow 8 hours for each unmerged row and 16 hours for each merged pair (96 hours total; 12 hours a week on average). Use the tracker to pick your next tasks. Check NCEES rescheduling rules if you're considering a new date.
Fast at math, slow at lookupsMove one or two topic hours a week into reference drills, but keep solving problems to test that what you found actually fits.

Exam day: rules that change how you work

  • Time: a 9-hour appointment includes a 2-minute nondisclosure agreement, an 8-minute tutorial, 8 hours of exam time, and a 50-minute scheduled break (NCEES). Eight hours for 80 questions averages 6 minutes each.
  • Two halves: after roughly half the questions, you review and submit them. Once submitted, you can't go back to them. The optional scheduled break comes after that (Examinee Guide, pp. 11–12).
  • Unscheduled breaks are allowed, but the clock keeps running (Examinee Guide, p. 12).
  • Formats: multiple choice, plus alternative item types: multiple correct, point and click, drag and drop, and fill in the blank. Every item is scored right or wrong with no partial credit (NCEES CBT).
  • No penalty for guessing. Your score comes from correct answers only, so never leave a blank (NCEES scoring).
  • Unscored pretest items are mixed in, and you can't tell which they are (Examinee Guide, p. 11).
  • Units: both SI and U.S. customary appear (spec).
  • What you bring and what you get: one NCEES-approved calculator; a TI-30XS is also available on screen. The test center supplies 2 reusable booklets and 3 markers (Examinee Guide, pp. 8–9). NCEES's 2026 approved list covers HP 33s and 35s, Casio fx-115 and fx-991 models, and TI-30X and TI-36X models (NCEES memo, Oct. 20, 2025). If you test in 2027, check NCEES's calculator policy for that year rather than assuming the 2026 list carries over.
  • Arrive 30 minutes early with a current, physical photo ID that meets NCEES's ID requirements; its first and last names must match your appointment (Examinee Guide, pp. 8–9).

Scoring, pass rates, retakes, and fees

Passing score: NCEES doesn't publish it. Raw correct answers are converted to a scaled score that adjusts for small differences between exam forms, and results are reported as pass or fail (NCEES scoring). If you don't pass, you get a diagnostic report showing how you did in each knowledge area compared with passing examinees (Examinee Guide, pp. 14, 20–21). Results usually arrive 7–10 days after the exam (NCEES). More on reading results: NCEES exam results.

Pass rates: for January–June 2026, NCEES reports that 63% of 434 first-time takers and 44% of 201 repeat takers passed Civil: Geotechnical. These figures cover examinees testing under NCEES member boards (NCEES pass-rate table, updated July 2026).

Retakes: NCEES allows one attempt per quarterly testing window (January–March, April–June, July–September, October–December) and no more than three in any 12 months. Your board may be stricter (Examinee Guide, p. 5). Full details: NCEES retake policy.

Fees and eligibility: the exam fee is $400 per attempt, paid to NCEES. Some boards charge a separate application fee, and your licensing board decides whether you're eligible to sit (NCEES; Examinee Guide, pp. 2–3). Passing the exam is one step toward a license; your board issues the license itself. Find yours in the NCEES licensing board directory. Registration walkthrough: how to register for an NCEES exam. Need testing accommodations? Request them during registration; see NCEES exam accommodations.

Common questions

Is the PE Civil Geotechnical exam open book? It's closed book with electronic references. NCEES supplies the handbook and the listed standards on screen, and you can't bring personal copies (NCEES).

Is there still a breadth section? No. The current specification covers geotechnical knowledge areas only. The exam has two sections with one shared answering-time budget, and both draw on the same ten-area specification (spec; Examinee Guide, p. 11).

Not at the PE stage yet? If you're still working toward the FE exam, start with FE Civil exam prep.

Sources

NCEES (exam owner)

Technical references used in the solutions

Last verified October 7, 2026: exam format, timing, fees, retake and exam-day rules, both design-standard lists, the 2026 calculator list, pass rates, and the technical references cited in each solution. The Castleport Test Prep Editorial Team researched and wrote this page with AI assistance. We checked the exam-administration facts and the technical methods used here against the linked sources and recalculated every answer. That is source and calculation checking, not professional engineering review, and the problems are for exam study, not project design.

Castleport Test Prep is an independent exam prep publisher and is not affiliated with, endorsed by, or approved by NCEES. The practice problems on this page are original and unofficial, not questions from any NCEES exam. Exam and credential names are used to identify their subjects; trademarks belong to their respective owners.

PE Civil Geotechnical Exam Prep: 19 Free Problems & Study Plan