Curbs are the circulation elements that make up the edge of where a raised sidewalk or a median meets a street or roadway. The main purpose of Curbs is to help delineate the edge of the pavement that separates the road from sidewalks and prevent drivers from possibly parking and driving on any sidewalks or lawns. Curbs also help promote structural support to the edge of a pavement and can help direct any runoff water from rain or melted snow into storm drains. Curbs are often categorized by shape, material, height, and whether the curb is combined with a gutter.
Curbs, those raised edges lining our streets, originally emerged as simple stone borders to manage runoff in ancient civilizations. As urban areas grew, so did the role of curbs. By the 18th and 19th centuries, they became key to separating pedestrians from traffic, establishing order in bustling cities. They also facilitated effective drainage, reducing flooding. Over time, materials shifted from stone to concrete, adapting to the changing needs of expanding urban infrastructure.
Curbs are evolving to suit modern cityscapes. With the rise of shared spaces, some areas are blending curbs into the road, using color and texture differences instead of height. Elsewhere, adaptive curbs change use based on time of day, reserving spaces for pedestrians, cyclists, or vehicles as needed. In greener cities, permeable curbs aid in rainwater absorption, mitigating urban flooding. Innovations like these ensure that curbs continue shaping safe and efficient urban environments.
A curb cut (also called a curb ramp, depressed curb, dropped curb, or pram ramp) is a ramped section of curb that allows pedestrians to cross the street at an intersection without having to climb over the curb. Curb cuts are designed primarily for wheelchair users, but they also benefit people with strollers, baby carriages, bicycles, and other wheeled devices.
The main difference between a barrier curb and a mountable curb is that a barrier curb is vertical and cannot be driven over, while a mountable curb has a sloping face that allows vehicles to drive over it without damaging their tires.
Curbs are typically made of concrete or stone. They are created by pouring concrete into forms or by using a slipform machine. The type of curb that is used will depend on the specific project requirements. For example, hand-made curbs may be used for smaller projects, while slip form casting machines may be used for larger projects or projects that require a high level of precision.