A barricade is any structure that obstructs or controls passage. Some barricades are meant to provide visual guidance while others are meant to create a physical obstruction. To work well, a barricade needs to be easy to see and easy to interpret. There are several categories of barricades:
- Traffic safety. Traffic safety barricades are meant to be safe, stable, visible barricades that direct the flow of traffic or prevent entrance or exit from designated areas.
- Crowd management. Crowd management barricades are designed for the safety and security of a group of people, to control the direction of their travel and to contain their numbers.
- Security. A security barricade is meant to prevent access or entrance to a specific area, such as a hazardous waste area, or to protect from theft. Security barricades may be designed to withstand assaults such as high speed impacts.
Barricades can be constructed out of a variety of materials depending upon their projected use and the degree of solidity and permanence required:
- Concrete. Concrete barriers are good for withstanding high impact and for withstanding snow load. Most are familiar with the classic "New Jersey" concrete barricades that line the medians and shoulders of highways across the country, but concrete comes in many different textures and shapes these days. Concrete that is reinforced with steel or fiber, as is often the case, is known as reinforced concrete.
- Steel/Metal. Sometimes called bike rack barricades, some steel barricades can indeed look like bicycle racks. Generally made of steel tubing that is galvanized for extra strength and durability, metal barricades come in a variety of sizes, designs, and even colors. You'll find a good visual example of a steel barricade at TravelBlog.
- Plastic and Vinyl. Plastic and vinyl barricades have the advantage of being a bit less intimidating than metal or concrete barricades. They also tend to be more lightweight, and thus are much easier to transport than metal or concrete barricades. They also come in a variety of styles and colors. Plastic barricades are great for sporting events, fairs, amusement parks, festivals, you get the idea-places where you want people to feel festive, and not contained.
- Rope. Think velvet, think theatre. This is the most polite and understated of barricades you'll find. Expect it at performances by the orchestra, and and not Black Sabbath.
- Tape. You may be familiar with this type of barricade in the form of police tape. Non-adhesive tape, usually with a message across it, along the lines of "CAUTION" or "DO NOT CROSS" is used to create a visual boundary.