Foundation Engineering Simulations

A collection of interactive 3D visualizations and simulations to help you master concepts in foundation engineering.

Subsurface Exploration and Site Characterization - Theory & Concepts

Planning exploration programs, interpreting boring logs, and determining bearing capacity from field tests.

SPT N-Value Correction Calculator

Field Blow Count,

N_{field}

: 15

Hammer Efficiency,

\\eta_H

(%): 60

Rod Length (m): 5

Test Depth,

z

(m): 5

Soil Unit Weight,

\\gamma

(kN/m³): 18

Energy-Corrected Blow Count

N_{60}

= 0.0

Accounts for hammer efficiency and rod length.

Overburden Correction Factor

C_N

= 0.00

Normalizes to 100 kPa effective stress.

Fully Corrected Blow Count

(N_1)_{60}

= 0

Used for design correlations (e.g., relative density, bearing capacity).

The Standard Penetration Test (SPT) involves dropping a 140 lb hammer 30 inches. Different hammers transfer energy differently. The $N_{60}$ normalizes this to 60% theoretical free-fall energy. $C_N$ adjusts for depth, because soil at greater depths appears artificially stronger due to confinement.

Lateral Earth Pressure - Theory & Concepts

At-rest, active, and passive earth pressures, Rankine's and Coulomb's theories.

Lateral Earth Pressure Calculator

Theory

Friction Angle,

\phi'

: 30°

Backfill Slope,

\beta

: 0°

Must be ≤ $\phi'$

Fixed Parameters:

Wall Height (H): 5.0 m
Soil Unit Weight ( $\gamma$ ): 18 kN/m³
Cohesion ( $c'$ ): 0 kPa

Active Coeff (

K_a

)

0.333

Force (

P_a

)

75.0 kN/m

Passive Coeff (

K_p

)

3.000

Force (

P_p

)

675.0 kN/m

Pressure Distribution vs. Depth

Loading chart...

Retaining Walls - Theory & Concepts

Types of retaining walls, stability analysis, and design principles.

MSE Wall Internal Stability Visualizer

Wall Height (H = 6 m)

Friction Angle (φ' = 30°)

Unit Weight (γ = 18 kN/m³)

Active Earth Pressure Coeff.

K_a = \frac{1 - \sin(30^\circ)}{1 + \sin(30^\circ)} = 0.333

Maximum Pressure at Base

p_a = \gamma \cdot H \cdot K_a = 36.0 \text{ kPa}

Total Thrust Force

P_a = \frac{1}{2} \gamma H^2 K_a = 108.0 \text{ kN/m}

Bearing Capacity of Shallow Foundations - Theory & Concepts

Modes of failure, Terzaghi's and general bearing capacity equations.

Bearing Capacity Simulator (Square Footing)

Width, B (m): 2

Depth, Df (m): 1

Friction Angle,

\\phi

(deg): 30

Cohesion, c (kPa): 10

Ultimate Bearing Capacity

0.0 kPa

Calculated using Terzaghi's formula for square footing.

The red dashed lines represent the potential shear failure surface in the soil. As $\\phi$ increases, the failure surface extends further outward, mobilizing more soil resistance.

Design of Shallow Foundations - Theory & Concepts

Design of isolated, combined, strap footings, and mat/raft foundations.

Shallow Foundation Sizing & Pressure

Axial Load,

P

(kN): 1000

Overturning Moment,

M

(kN·m): 0

Allowable Bearing,

q_{all}

(kPa): 150

Required Square Width (

B

)

0.0 m

Maximum Soil Pressure (

q_{max}

)

0.0 kPa

Eccentricity (

e = M/P

)

0.00 mLimit

B/6

: 0.00 m

The simulator automatically increases the footing width ( $B$ ) until the maximum soil pressure ( $q_{max}$ ) is below the allowable bearing capacity. When a moment is applied, the pressure becomes trapezoidal. If eccentricity ( $e$ ) exceeds $B/6$ , tension develops at the heel (shown as $q_{min} = 0$ ).

Deep Foundations (Piles) - Theory & Concepts

Types, classification, load transfer, static/dynamic capacity, and pile group efficiency.

Single Pile Capacity Estimator

Pile Length, L (m): 10

Pile Diameter, D (m): 0.5

Friction Angle,

\\phi

(deg): 30

Total Capacity (

Q_u

)

0 kN

Skin Friction (

Q_s

)0 kN

Tip Resistance (

Q_p

)0 kN

Using Beta Method for skin friction and Nq method for tip resistance.

Blue arrows represent skin friction resistance ( $Q_s$ ) acting along the shaft. The red arrow represents point bearing resistance ( $Q_p$ ) acting at the tip.

Drilled Shafts and Caissons - Theory & Concepts

Construction methods and bearing capacity calculations for drilled shafts.

Drilled Shaft Capacity in Clay

Shaft Diameter (

D

)1.5 m

Shaft Length (

L

)15.0 m

Undrained Cohesion (

c_u

)100 kPa

Adhesion Factor (

\\alpha

)0.55

Tip Resistance

Q_p = A_p \cdot c_u \cdot N_c = 1590 \text{ kN}

Skin Friction

Q_s = p \cdot L \cdot \alpha \cdot c_u = 3888 \text{ kN}

Total Ultimate Capacity

Q_u = Q_p + Q_s = 5478 \text{ kN}

Soil Improvement - Theory & Concepts

Techniques for enhancing soil properties: compaction, preloading, vibroflotation, and geosynthetics.

Consolidation Acceleration with PVDs

Clay Thickness,

H

(m): 10

C_v

(m²/yr): 2.0

Install Prefabricated Vertical Drains (PVD)

PVD Spacing,

s

(m): 1.5

Time to 90% Consolidation (

t_{90}

)

0.0 months

Accelerated via radial drainage!

Without drains, water must travel vertically through the entire clay layer (slow). Prefabricated Vertical Drains (PVDs) shorten the drainage path to half the spacing distance, converting vertical flow to rapid radial flow. Notice how settlement time drops from years to months.

Sheet Pile Walls and Braced Cuts - Theory & Concepts

Design and analysis of cantilever, anchored sheet pile walls, and braced excavations.

Cantilever Sheet Pile Visualizer

Excavation Depth ($H$): 4.0 m

Friction Angle ($\phi'$): 30.0°

Unit Weight ($\gamma$): 18.0 kN/m³

$K_a = 0.333$

$K_p = 3.000$

$D_{req} \approx 2.12 \text{ m}$

Total Length = 6.12 m

Machine Foundations - Theory & Concepts

Soil dynamics, natural frequency, and vibration isolation for equipment foundations.

Foundation Resonance Calculator

Dynamic Spring Constant ($k_z$): 8.5 $\times 10^5$ kN/m

Total Weight (Machine + Block): 1200 kN

Machine Operating Speed ($N$): 450 RPM

Natural Frequency ($f_n$)

13.27 Hz

Operating Freq ($f_m$)

7.50 Hz

Frequency Ratio ($f_n / f_m$)

1.77

Safe (High-Tuned)

Target ratio: > 1.5 (High-tuned) or < 0.5 (Low-tuned). Values near 1.0 indicate severe resonance.