The prominence of bollards has dramatically increased in the past decade as a result of heightened fears about security. These are a simple, practical, and cost-effective means of erecting anti-ram perimeter defense without creating a visual sense of a fortified bunker. Bollards are widely used for traffic direction and control, and in purely decorative applications. However, bollards for sale can serve many characteristics beyond security. They can be used purely aesthetic purposes, functioning as landscaping elements. Bollards can create visible boundaries of any property, or separate 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 many different circumstances. They frequently tell us where we can 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 like lighting, security cameras, bicycle parking or even seating. Decorative bollards are produced in a selection of patterns to harmonize with an array 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 created to fit as covers over standard steel pipe sizes, adding pleasing form to 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, plus they are still used today. A typical marine bollard is created in cast iron or steel and shaped somewhat like a mushroom; the enlarged top is made to prevent mooring ropes from slipping off.
Today, the term bollard also describes a variety of structures utilized on streets, around buildings, and in landscaping. According to legend, the first street bollards were actually cannons – sometimes reported to be captured enemy weapons – planted in the ground as boundary posts and town markers. When the availability of former cannons was utilized up, similarly shaped iron castings were designed to match the same functions. Bollards have since evolved into many varieties which are widely employed on roads, specifically in urban areas, as well as outside supermarkets, restaurants, hotels, shops, government buildings and stadiums.
The most typical kind 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 only simple posts, but in addition a multitude of 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 number of metallic, painted, and durable powder coat finishes.
Removable bollards are utilized where the requirement to limit access or direct traffic changes occasionally. Both retractable and fold-down styles are employed where selective entry is often needed, and they are designed and so the bollard can be easily 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 count on how much they weigh rather than structural anchoring in which to stay place. They are designed to be moved rarely, then just with heavy machinery for instance a fork-lift.
Bollards generally belong to three types of applications:
Decorative Bollards – decorative bollards for architectural and landscaping highlights;
Traffic and Safety Bollards – bollards which provide asset and pedestrian safety, in addition to 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 can border, divide, or define an area. They may also 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 second lean toward visual simplicity – often straight-sided posts with a number of reveals close to the top. Styles made to match various historic periods will often have more elaborate shapes and surface details. Such as flutes, bands, scrolls along with other ornamentation.The post-top is actually 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 making use of them for impromptu seating. On the contrary, they may be 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 often made from iron or aluminum casting. Aluminum bollards are desirable for applications where weight is a problem, for instance a removable bollard. Aluminum units tend to be a little more expensive than iron. For applications when a decorative bollard may be subject to destructive impact, ductile iron is really 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 regular foundry technique which is economical and well-fitted to objects this size. However, sand-cast objects frequently bear surface irregularities that often leave the finished product less attractive to the attention. If high-finish consistency is desired, seek a manufacturer that will machine 100% in the surface after casting to produce units with a uniform surface for optimum looks.
Finish is a crucial 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 subjected to a fairly aggressive environment; petrochemical residues and splashes of diluted road de-icing salts may compromise some painted finishes. Factory-applied powder coating – which is available on iron, aluminum, and steel – is surely an especially durable type of painted finish. The applying process builds a coating with very consistent coverage. During coating, any bare metal is likely 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, bollard covers manufactured from aluminum might be a better option than iron. If the finish coat is damaged, aluminum oxidizes to a color that is certainly generally more acceptable compared to the red rust produced by iron. Aluminum and stainless steel are also offered in a variety of bare metal finishes. Functionality could be included in the otherwise decorative bollard. As an example, common option 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 in the post allows parking and locking of bicycles, an extremely popular choice as increasing numbers of people seek alternative green transportation. Bollards may also contain lighting units or security devices, like motion sensors or cameras.
Traffic and Safety Bollards
The most frequent bollard applications are traffic direction and control, along with safety and security. The very first function is achieved through the visual presence in the bollards, and at some level by impact resistance, although, in these applications visual deterrence will be the primary function. Security and safety applications depend on higher levels of impact resistance. The key distinction between the 2 is safety designs are involved with stopping accidental breach of a defined space, whereas security is all 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 the two, for instance, allows easy passage for humans and human-powered vehicles – like wheelchairs or shopping carts – but prevents the passage of cars. Such installations tend to be seen facing zcvjbu parking lot entrance to some store, and at the mouths of streets changed into outdoor malls or ‘walk streets’. In designing bollard installations to get a site, care has to be taken 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 do not require impact resistance. A type of bollards linked by a chain presents a visual cue never to cross the boundary, although it may be easy enough for a pedestrian to visit over or beneath the chain if they choose. Bollards made to direct traffic are occasionally made to fold, deflect, or break away on impact.
Adding greater collision resistance allows a bollard to enforce traffic restrictions instead of merely suggesting them. Plain pipe bollards are frequently placed in the corners of buildings, or flanking lamp-posts, public phones, fire hydrants, gas pipes along with other installations that should be protected from accidental contact. A bollard at the edge of a roadway prevents cars from over-running sidewalks and harming pedestrians. Bell-shaped bollards can actually redirect a vehicle back to 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 especially common at corners where vehicle drivers often misestimate turns, and pedestrians are especially close to the roadbed waiting to cross. In a few cities, automatically retractable impact-resistant bollards are installed to control the flow of traffic into an intersection. Internet videos of ‘bollard runners’ graphically demonstrate the strength of even a low post at stopping cars.