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Transportation Engineering Simulations

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

Highway Geometric Design - Theory & Concepts

Principles of cross-section elements, horizontal alignment, and vertical alignment.

Highway Cross-Section Builder

Total ROW: 43.4mMedian 5m2x3.6mSh. 3mClear Zn 9m
5 m

Traffic Flow Theory - Theory & Concepts

Fundamental relationships of traffic flow (flow, speed, density), stream models, and shockwave theory.

Traffic Flow Theory (Greenshields Model)

Model Parameters

Free-Flow Speed (u_f)80 km/h
Jam Density (k_j)100 veh/km

Current Traffic State

Current Density (k)25 veh/km
Speed (u)60.0 km/h
Flow (q)1500 veh/h
Capacity (q_max)2000 veh/h
Optimum Speed40.0 km/h
Flow vs. Density (q-k)
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Speed vs. Density (u-k)
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Highway Capacity and Level of Service - Theory & Concepts

Concepts of capacity, level of service (LOS), and analysis of highway facilities.

Level of Service (LOS) Simulator

Current LOSB
Avg Speed68 mph

"Reasonably free flow. Freedom to maneuver is slightly restricted."

Traffic Density15 pc/mi/ln
A
B
C
D
E
Based on Highway Capacity Manual (HCM) density thresholds for basic freeway segments.

Intersection Control and Design - Theory & Concepts

Principles of intersection design, conflict points, and control types (stop, yield, roundabouts).

Conflict Point Simulator

4-Leg Cross Intersection

Crossing Conflicts:16
Merging Conflicts:8
Diverging Conflicts:8
Total Points:32

The traditional cross intersection has a high number of crossing conflicts, which are the most dangerous type.

Crossing (High Severity)
Merging (Med Severity)
Diverging (Low Severity)

Traffic Signal Design - Theory & Concepts

Principles of signal phasing, timing, and capacity analysis for signalized intersections.

Traffic Signal Timing Simulator

Adjust the cycle length and phase distributions to observe how green, amber, and all-red clearance intervals allocate time to competing traffic streams at an intersection.

60 sec
30 sec
3 sec
2 sec
Time: 0s / 60s
North/South
🛣️
East/West
E/W Green
Y
N/S Green
Y

Public Transportation Systems - Theory & Concepts

Overview of public transit modes, characteristics, capacity, and operations.

Transit Fleet Size & Scheduling Simulator

Adjust the route parameters to see how running time and layovers dictate the required fleet size to maintain a specific headway.

50 min
10% (5 min)
10 min
Total Cycle Time ($T_c$)55 min
Theoretical Vehicles ($T_c / h$)5.50
Required Fleet Size ($N$)6 buses
Actual Scheduled Headway9.2 min
Resulting Frequency ($f$)6.5 buses/hr

Pavement Design - Theory & Concepts

Principles of flexible and rigid pavement design, ESAL calculations, and the AASHTO method.

AASHTO Flexible Pavement Design

Design Inputs

Lower $M_R$ means weaker soil, requiring a thicker pavement.

Layer Thicknesses (inches)

Required SN:0.00
Provided SN:0.00
✅ DESIGN ADEQUATE
30" -
20" -
10" -
0" -
HMA Surface (4")
Base Course (6")
Subbase (8")
Subgrade$M_R$ = 5000 psi

Railway Engineering - Theory & Concepts

Principles of railway track structure, train resistance, geometric design, and operations.

Railway Track Structure

Controls

Narrow (1000)Standard (1435)Broad (1676)

Info

The track structure distributes immense point loads from the wheels safely to the subgrade.

1435 mm Gauge

Airport Engineering - Theory & Concepts

Principles of airport planning, runway orientation, length corrections, and geometric design.

Runway Length Correction Simulator

Air density decreases at higher altitudes.

Std. Temp at 600m is 11.1°C.

Sequential Corrections

1. Elevation Corrected:2052.0 m
2. Temp Corrected (Applied to #1):2316.7 m
3. Gradient Corrected (Applied to #2):2455.7 m
Final Required Length:2455.7 m
+36.4% penalty
BASIC
0m2455.7m