When analyzing roads, intersections, and traffic flow, engineers face a common challenge: vehicles are not all the same. A car, a motorcycle, a truck, and a rickshaw each take up different amounts of road space, move at different speeds, and influence congestion differently. To solve this, transportation engineers use the Passenger Car Unit (PCU) — […]
What is an ESAL? ESAL Formula Where: Typical Load Equivalency Factors (LEFs) (based on AASHTO & typical LEFs) Vehicle Type Axles Typical Load (kips per axle) Approx. ESAL per Pass Passenger Car (sedan) 2 2–3 0.0004 Pickup / SUV 2 3–4 0.001 Delivery Van (2-axle, light) 2 4–5 0.005 Single-Unit Truck (2-axle, 6-tire) 2 6–9
Transportation planning and engineering is one of the most dynamic and impactful career paths available today. It sits at the intersection of technology, infrastructure, sustainability, and public policy. If you’ve ever searched “Should I study transportation engineering?” or “Is traffic engineering a good career?”, this guide will help you understand why the answer is a
When planning a new road, street, or highway, one of the most important decisions you’ll face is whether to use flexible or rigid pavement. Each has its advantages, costs, and ideal use cases. Choosing the right type of pavement can save millions in construction and maintenance over the project’s lifecycle. In this post, we break
In road design, traffic load isn’t just about how many vehicles pass each day — it’s about how much stress those vehicles place on the pavement over time. That’s where ESALs come in. If you’re involved in pavement design, planning, or construction, understanding Equivalent Single Axle Loads (ESALs) is essential. This article explains what ESALs
Designing a durable and cost-effective road starts with a strong pavement foundation. In Pakistan, flexible pavement remains the most common choice for urban roads, highways, and access streets. But how do engineers determine the thickness of each pavement layer — from subgrade to asphalt? This article walks you through the basics of flexible pavement design
