The popularity of bollards has dramatically increased in the past decade as a result of heightened concerns about security. They are a simple, practical, and cost-effective means of erecting anti-ram perimeter defense without developing a visual sense of a fortified bunker. Bollards are popular for traffic direction and control, as well as in purely attractive applications. However, plastic safety bollards can provide many features beyond security. They can be used as purely aesthetic purposes, functioning as landscaping elements. Bollards can create visible boundaries of a property, or split areas within sites. They can control traffic and are often arranged to allow pedestrian access while preventing entry of vehicles.
Removable and retractable bollards can allow different levels of access restriction for a number of circumstances. They frequently tell us where we could and cannot drive, park, bike, or walk, protect us from crime, shield vehicles and property from accidents, and add aesthetic features to our building exteriors and surrounding areas. Bollards can incorporate other functions such as lighting, surveillance cameras, bicycle parking or perhaps seating. Decorative bollards are created in a selection of patterns to harmonize with an array of architectural styles. The prevalence of the very most common type of security bollard, the concrete-filled steel pipe, has encouraged the manufacturing of decorative bollards created to fit as covers over standard steel pipe sizes, adding pleasing form for the required function.
Exactly What Is A Bollard?
A bollard is actually a short vertical post. Early bollards were for mooring large ships at dock, and they are generally still being used today. A normal marine bollard is produced in cast iron or steel and shaped somewhat such as a mushroom; the enlarged top is designed to prevent mooring ropes from slipping off.
Today, the term bollard also describes a variety of structures applied to streets, around buildings, and then in landscaping. According to legend, the initial street bollards were actually cannons – sometimes said to be captured enemy weapons – planted in the earth as boundary posts and town markers. If the availability of former cannons was used up, similarly shaped iron castings were designed to match the same functions. Bollards have since evolved into many varieties that are widely employed on roads, specifically in urban areas, along with outside supermarkets, restaurants, hotels, shops, government buildings and stadiums.
The most frequent kind of bollard is fixed. The simplest is definitely an unaesthetic steel post, about 914 to 1219 mm (36 to 48 in.) above-grade. Specially manufactured bollards include not just simple posts, but also numerous decorative designs. Some feature square or rectangular cross-sections, but most are cylindrical, sometimes having a domed, angled, or flat cap. They are available in a variety of metallic, painted, and sturdy powder coat finishes.
Removable bollards are used where the need to limit access or direct traffic changes occasionally. Both retractable and fold-down styles are employed where selective entry is frequently needed, and therefore are designed and so the bollard can easily be collapsed to ground level and quickly re-erected. Both retractable units could be manually operated or automated with hydraulic movements. Movable bollards are large, heavy objects – frequently stone or concrete – that depend on how much they weigh instead of structural anchoring to remain in place. They are designed to be moved rarely, then only with heavy machinery for instance a fork-lift.
Bollards generally fall into three types of applications:
Decorative Bollards – decorative bollards for architectural and landscaping highlights;
Traffic and Safety Bollards – bollards which provide asset and pedestrian safety, as well as traffic direction; and
Security Bollards and Post Covers – decorative, impact-resistant bollard enhancements
Some bollards are intended purely to become an ornament. As standalone architectural or landscaping features, they can border, divide, or define an area. They can be accents, sentries, or supporting players to larger, more dramatic architectural gesture.
Decorative bollards are manufactured to harmonize with both traditional and contemporary architectural styles. The second lean toward visual simplicity – often straight-sided posts with one or more reveals nearby the top. Styles made to match various historic periods usually have more elaborate shapes and surface details. Such as flutes, bands, scrolls and other ornamentation.The post-top is really a distinctive feature; traditional bollard design often includes elaborate decorative finials, whereas contemporary versions frequently feature a simple rounded or slanted top to discourage passersby from leaving trash or using them for impromptu seating. On the contrary, these are sometimes made flat and broad specifically to encourage seating. Common decorative bollard materials include iron, aluminum, stainless-steel, and concrete.
Ornamental designs with elaborate detail are frequently made of iron or aluminum casting. Aluminum bollards are desirable for applications where weight is an issue, such as a removable bollard. Aluminum units tend to be slightly more expensive than iron. For applications where a decorative bollard may be susceptible to destructive impact, ductile iron is a safer choice than more brittle metals, as force will deform the metal rather than shatter and transforming it into possible hazardous flying projectiles.
Iron and aluminum bollards are often manufactured by sand-casting – a conventional foundry technique which is economical and well-suited to objects this size. However, sand-cast objects frequently bear surface irregularities that tend to leave the finished product less attractive to the attention. If high-finish consistency is desired, seek a manufacturer that will machine 100% from the surface after casting to generate units with a uniform surface for maximum visual appeal.
Finish is a vital consideration in a decorative bollard, from functional in addition to aesthetic standpoints. Bollards are, by their nature, susceptible to being scratched or nicked by pedestrians and vehicles. Those located near roadways are in contact with a reasonably aggressive environment; petrochemical residues and splashes of diluted road de-icing salts may compromise some painted finishes. Factory-applied powder coating – which can be available on iron, aluminum, and steel – is surely an especially durable form of painted finish. The applying process builds up a coating with very consistent coverage. During coating, any bare metal tends to attract the powder, eliminating pinholes in coverage. The baking procedure that completes the finish gives it additional toughness and abuse resistance.
In applications where greater physical abuse is predictable, plastic bollard covers made from aluminum can be a better choice than iron. When the finish coat is damaged, aluminum oxidizes to some color which is generally more acceptable compared to red rust made by iron. Aluminum and stainless can also be found in a quantity of bare metal finishes. Functionality may be added to the otherwise decorative bollard. For example, common option is the chain eye – linking two or more bollards with chain, creating a simple traffic direction system. A sizable metal loop or arm on the side from the post allows parking and locking of bicycles, an increasingly popular choice as increasing numbers of people seek alternative green transportation. Bollards could also contain lighting units or security devices, including motion sensors or cameras.
Traffic and Safety Bollards
The most frequent bollard applications are traffic direction and control, together with security and safety. The first function is achieved from the visual presence in the bollards, and at some level by impact resistance, although, within these applications visual deterrence is the primary function. Security and safety applications depend upon higher amounts of impact resistance. The major distinction between both is safety designs are involved with stopping accidental breach of the defined space, whereas security is about stopping intentional ramming.
Closely spaced lines of bollards can form a traffic filter, separating motor vehicles from pedestrians and bicycles. Placing the posts with 1 m (3 ft) of clearance between them, for instance, allows easy passage for humans and human-powered vehicles – such as wheelchairs or shopping carts – but prevents the passage of cars. Such installations tend to be seen before zcvjbu parking area entrance to your store, and also at the mouths of streets changed into outdoor malls or ‘walk streets’. In designing bollard installations to get a site, care must be come to avoid locating them where they will likely be a navigational hazard to authorized vehicles or cyclists.
Some applications for traffic guidance depend on the cooperation of drivers and pedestrians and you should not require impact resistance. A collection of bollards linked by a chain presents a visual cue not to cross the boundary, though it could be easy enough to get a pedestrian to go over or beneath the chain should they choose. Bollards created to direct traffic are often designed to fold, deflect, or break away on impact.
Adding greater collision resistance allows a bollard to enforce traffic restrictions rather than merely suggesting them. Plain pipe bollards are usually placed on the corners of buildings, or flanking lamp-posts, public phones, fire hydrants, gas pipes along with other installations that need to be protected against accidental contact. A bollard on the fringe of a roadway prevents cars from over-running sidewalks and harming pedestrians. Bell-shaped bollards can actually redirect an automobile back to the roadway when its wheels hit the bollard’s sloped sides.
They may be employed where U-turns and tight-radius turns are frequent. This kind of usage is especially common at corners where vehicle drivers often misestimate turns, and pedestrians are specifically near the roadbed waiting to cross. In some cities, automatically retractable impact-resistant bollards are installed to manage the flow of traffic into an intersection. Internet videos of ‘bollard runners’ graphically demonstrate the strength of also a low post at stopping cars.