"The geometric design of roads is the branch of highway engineering concerned with the positioning of the physical elements of the roadway according to standards and constraints."
This involves the design and layout of highways, including alignment, cross-section, and vertical and horizontal curves.
Horizontal alignment: The study of horizontal curves and their design to provide safe and efficient travel for vehicles.
Vertical alignment: The study of vertical curves for roads, highways, and other infrastructure projects.
Superelevation: The application of banked curves on roads to allow for higher speeds and greater safety.
Sight distance: The distance traveled by a driver between the time they spot an obstacle and the time they reach it.
Intersection design: The design of intersections for motor vehicles, pedestrians, and bicycle traffic.
Roadside safety design: The design of safety features for roadsides including guardrails, barriers, medians, and crash cushions.
Access management: The control of access points on highways and roads to provide safety and traffic flow.
Grade separation: The creation of structures that allow for the separation of intersecting roadways.
Pavement design: The design of the structural and functional properties of pavement including thickness, drainage, and compaction techniques.
Cross-section elements: The design and layout of the various elements that make up the cross-section of a roadway including travel lanes, shoulder, medians, and ditches.
Highway capacity analysis: The analysis of the capacity of a highway or road, including the number of vehicles that can pass through per unit of time.
Traffic flow theory: Understanding the principles of traffic flow, including speed, volume, density, and congestion.
Highway safety: The study of safety measures and devices to prevent accidents and injuries on highways, including advancements in vehicle technology.
Geometric design for multimodal transportation: The design of infrastructure that accommodates all types of transportation modes including pedestrians, cyclists, and public transportation.
Traffic simulation: The use of computer programs to simulate traffic flow, evaluate potential changes in roadway design, and analyze performance metrics.
Horizontal alignment design: This type of design refers to the process where the roadway is aligned to fit the terrain, allowing vehicles to travel on a straight line or curve with ease.
Vertical alignment design: This type of design refers to the process that involves designing the vertical profile of the highways, such as grading, drainage, and slope.
Cross-section design: This type of design involves determining the width and other dimensions of the roadway, and the area of shoulders and medians, as well.
Intersection design: This type of design involves determining the layout of roads, marking, and illumination for intersections or junctions.
Roundabout design: This is a type of intersection design whereby various roads intersect, which features a circular or round-shaped center island, which provides a free flow of traffic.
Traffic signal design: It is the process of designing traffic signals, including the number, location, and timing for improved traffic control.
Interchange design: This type of design involves designing the interchanges, such as cloverleaf, diamond, and others.
Freeway design: This type of design involves designing grade-separated highways in the form of freeways that allow free and faster movement of the vehicles.
"The basic objectives in geometric design are to optimize efficiency and safety while minimizing cost and environmental damage."
"Geometric design also affects an emerging fifth objective called 'livability,' which is defined as designing roads to foster broader community goals."
"Designing roads to foster broader community goals, including providing access to employment, schools, businesses, and residences."
"Accommodate a range of travel modes such as walking, bicycling, transit, and automobiles."
"Minimizing fuel use, emissions, and environmental damage."
"Geometric roadway design can be broken into three main parts: alignment, profile, and cross-section."
"The alignment is the route of the road, defined as a series of horizontal tangents and curves."
"The profile is the vertical aspect of the road, including crest and sag curves, and the straight grade lines connecting them."
"The cross-section shows the position and number of vehicle and bicycle lanes and sidewalks, along with their cross slope or banking."
"Cross sections also show drainage features, pavement structure, and other items outside the category of geometric design."
"The basic objectives in geometric design are to optimize efficiency and safety while minimizing cost and environmental damage."
"The basic objectives in geometric design are to optimize efficiency and safety while minimizing cost and environmental damage."
"Geometric design also affects an emerging fifth objective called 'livability,' which is defined as designing roads to foster broader community goals."
"The basic objectives in geometric design are to optimize efficiency and safety while minimizing cost and environmental damage."
"Combined, they provide a three-dimensional layout for a roadway."
"Designing roads to foster broader community goals, including providing access to employment, schools, businesses, and residences."
"Accommodate a range of travel modes such as walking, bicycling, transit, and automobiles."
"The alignment is the route of the road, defined as a series of horizontal tangents and curves."
"Cross sections also show drainage features, pavement structure, and other items outside the category of geometric design."