The prominence of bollards has dramatically increased during the past decade as a result of heightened fears about security. These are a simple, practical, and cost-effective method of erecting anti-ram perimeter defense without creating a visual sense of a fortified bunker. Bollards are widely used for traffic direction and control, as well as in purely decorative applications. However, removable bollards for sale can provide many features beyond security. They can be used as purely aesthetic purposes, functioning as landscaping elements. Bollards can create visible boundaries of any property, or split areas within sites. They can control traffic and they are often set up to allow pedestrian access while preventing entry of vehicles.
Removable and retractable bollards can allow different amounts of access restriction for a variety of circumstances. They frequently tell us where we are able to and cannot drive, park, bike, or walk, protect us from crime, shield vehicles and property from accidents, and add aesthetic features to the building exteriors and surrounding areas. Bollards can incorporate other functions such as lighting, surveillance cameras, bicycle parking as well as seating. Decorative bollards are made in a number of patterns to harmonize with a variety of architectural styles. The prevalence of the most common type of security bollard, the concrete-filled steel pipe, has encouraged the manufacturing of decorative bollards made to fit as covers over standard steel pipe sizes, adding pleasing form for the required function.
Exactly What Is A Bollard?
A bollard is a short vertical post. Early bollards were for mooring large ships at dock, and they are still used today. A typical marine bollard is produced in cast iron or steel and shaped somewhat such as a mushroom; the enlarged top is made to prevent mooring ropes from slipping off.
Today, the phrase bollard also describes a number of structures applied to streets, around buildings, as well as in landscaping. According to legend, the first street bollards were actually cannons – sometimes said to be captured enemy weapons – planted in the earth as boundary posts and town markers. When the supply of former cannons was used up, similarly shaped iron castings were created to match the same functions. Bollards have since evolved into many varieties which can be widely employed on roads, particularly in urban areas, as well as outside supermarkets, restaurants, hotels, shops, government buildings and stadiums.
The most common type of bollard is fixed. The easiest is surely 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 a wide variety of decorative designs. Some feature square or rectangular cross-sections, but a majority of are cylindrical, sometimes having a domed, angled, or flat cap. They come in a selection of metallic, painted, and sturdy powder coat finishes.
Removable bollards are employed where the necessity to limit access or direct traffic changes occasionally. Both retractable and fold-down styles are employed where selective entry is often needed, and therefore are designed and so the bollard can easily be collapsed to ground level and quickly re-erected. Both retractable units might be manually operated or automated with hydraulic movements. Movable bollards are large, heavy objects – frequently stone or concrete – that rely on how much they weigh instead of structural anchoring to remain in place. They are made to be moved rarely, and after that only with heavy machinery for instance a fork-lift.
Bollards generally fall under three varieties of applications:
Decorative Bollards – decorative bollards for architectural and/or 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 be an ornament. As standalone architectural or landscaping features, they could border, divide, or define a space. They can be accents, sentries, or supporting players to larger, more dramatic architectural gesture.
Decorative bollards are made to harmonize with both traditional and contemporary architectural styles. The latter lean toward visual simplicity – often straight-sided posts with a number of reveals near the top. Styles designed to match various historic periods usually have more elaborate shapes and surface details. These include flutes, bands, scrolls as well as other ornamentation.The post-top is really a distinctive feature; traditional bollard design often includes elaborate decorative finials, whereas contemporary versions frequently come with a simple rounded or slanted top to discourage passersby from leaving trash or utilizing them for impromptu seating. On the other hand, they 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 usually made from iron or aluminum casting. Aluminum bollards are desirable for applications where weight is a concern, for instance a removable bollard. Aluminum units tend to be slightly more expensive than iron. For applications in which a decorative bollard could be subject to destructive impact, ductile iron is really a safer choice than more brittle metals, as force will deform the metal as opposed to shatter and transforming it into possible hazardous flying projectiles.
Iron and aluminum bollards are often manufactured by sand-casting – a regular foundry technique that is economical and well-suitable for objects this size. However, sand-cast objects frequently bear surface irregularities that often leave the finished product less popular with the attention. If high-finish consistency is desired, seek a manufacturer that can machine 100% of the surface after casting to create units using a uniform surface for optimum looks.
Finish is a vital consideration in a decorative bollard, from functional in addition to aesthetic standpoints. Bollards are, by their nature, vulnerable 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 – that is on iron, aluminum, and steel – is definitely an especially durable form of painted finish. The applying process increases a coating with very consistent coverage. During coating, any bare metal tends to attract the powder, eliminating pinholes in coverage. The baking method that completes the conclusion gives it additional toughness and abuse resistance.
In applications where greater physical abuse is predictable, bollard cover made of aluminum can be a better option than iron. In the event the finish coat is damaged, aluminum oxidizes to a color that is generally more acceptable compared to red rust made by iron. Aluminum and stainless are also offered in a quantity of bare metal finishes. Functionality could be added to the otherwise decorative bollard. As an example, common choice is the chain eye – linking 2 or more bollards with chain, developing a simple traffic direction system. A large metal loop or arm on the side of the post allows parking and locking of bicycles, an increasingly popular choice as increasing numbers of people seek alternative green transportation. Bollards might also contain lighting units or security devices, like motion sensors or cameras.
Traffic and Safety Bollards
The most typical bollard applications are traffic direction and control, along with security and safety. The initial function is achieved through the visual presence of the bollards, and to some degree by impact resistance, although, within these applications visual deterrence is the primary function. Safety and security applications depend on higher amounts of impact resistance. The main distinction between both is safety designs are worried with stopping accidental breach of a defined space, whereas security is approximately 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, as an example, allows easy passage for humans and human-powered vehicles – such as wheelchairs or shopping carts – but prevents the passage of cars. Such installations are frequently seen before zcvjbu car park entrance to some store, and also at the mouths of streets changed into outdoor malls or ‘walk streets’. In designing bollard installations to get a site, care should be come to avoid locating them where they are going to 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 line of bollards linked by way of a chain presents a visual cue to not cross the boundary, even though it may be easy enough for a pedestrian to visit over or underneath the chain when they choose. Bollards made to direct traffic are sometimes made 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 often placed at the corners of buildings, or flanking lamp-posts, public phones, fire hydrants, gas pipes and other installations that ought to be protected from accidental contact. A bollard in the side of a roadway prevents cars from over-running sidewalks and harming pedestrians. Bell-shaped bollards can certainly redirect a vehicle back onto the roadway when its wheels hit the bollard’s sloped sides.
They are employed where U-turns and tight-radius turns are frequent. This kind of usage is particularly common at corners where vehicle drivers often misestimate turns, and pedestrians are specifically near to the roadbed waiting to cross. In certain 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 a low post at stopping cars.