What is Traffic Calming? Traffic calming refers to a range of design strategies and measures used to reduce vehicle speeds, improve road safety, and enhance the overall environment for pedestrians and cyclists. At its core, traffic calming is about shifting streets from being purely vehicle-dominated corridors to shared public spaces where safety and livability come […]
One of the most common questions in traffic impact assessments (TIAs) is whether to propose turning lanes, acceleration lanes, or deceleration lanes. While adding lanes may seem like a straightforward solution to congestion, proposing them without justification can create unnecessary cost, invite reviewer comments, or even compromise safety. In this post, we’ll explain when to
Road classification (or class) is a fundamental concept in transportation planning and traffic engineering. It provides a framework for organizing roads according to their function within the transportation network, specifically how they balance mobility (moving traffic efficiently) and access (serving adjacent land uses). Higher-class roads prioritize mobility, moving large volumes of traffic over longer distances
Swept path analysis (also referred to as vehicle tracking) is a core technical component of traffic engineering and site access review. It evaluates whether design vehicles can safely and realistically maneuver through intersections, site accesses, parking areas, and constrained roadway environments. For transportation planners, civil engineers, and approving agencies, swept path analysis provides defensible evidence
Designing streets and highways requires careful attention to geometric standards. Lane widths, sidewalk sizes, medians, and other roadway elements affect safety, efficiency, and comfort. This guide provides a comprehensive reference for planners and traffic engineers, including typical dimensions for freeways, arterials, collectors, and local streets. All dimensions are shown in meters and feet, based on
This glossary provides a comprehensive reference of commonly used abbreviations in transportation and traffic engineering. It covers terminology relevant to traffic studies, transportation planning, pavement design, and transit operations. Each entry includes a concise definition, with links to detailed guides or tools on Arterials.co, offering a reliable resource for professionals, planners, and students alike. Transportation
When designing roads, access drives, or service lanes around a development, engineers often focus on long-term operational traffic. However, in many projects, the most damaging traffic occurs during construction, not after completion. Heavy dump trucks, concrete mixers, low-bed trailers, and cranes can impose axle loads far greater than normal service vehicles. If construction traffic is
Transportation planning is becoming more complex than ever. Cities are expanding, travel behavior is shifting, and decision-makers are under pressure to deliver data-driven, sustainable solutions. Traditionally, transportation planners relied on manual surveys, static models, and limited datasets to understand how people and vehicles move. But with the explosion of digital data; GPS traces, camera feeds,
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
