The popularity of bollards has dramatically increased during the past decade due to heightened concerns about security. They are a basic, practical, and cost-effective method of erecting anti-ram perimeter defense without creating a visual sense of a fortified bunker. Bollards are popular for traffic direction and control, and in purely decorative applications. However, bollards can serve many functions beyond security. They can be used as purely aesthetic purposes, working as landscaping elements. Bollards can create visible boundaries of the property, or separate areas within sites. They can control traffic and therefore are often arranged to allow pedestrian access while preventing entry of vehicles.
Removable and retractable bollards can allow different degrees of access restriction for many different 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 made in a selection of patterns to harmonize with a wide range of architectural styles. The prevalence of the very common type of safety bollards, the concrete-filled steel pipe, has encouraged the manufacturing of decorative bollards designed to fit as covers over standard steel pipe sizes, adding pleasing form for the required function.
Exactly What Is A Bollard?
A bollard is really a short vertical post. Early bollards were for mooring large ships at dock, and they are generally still used today. A normal marine bollard is manufactured 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 word bollard also describes a number of structures applied to streets, around buildings, and in landscaping. In accordance with legend, the first street bollards were actually cannons – sometimes said to be captured enemy weapons – planted in the ground as boundary posts and town markers. Once the supply of former cannons was used up, similarly shaped iron castings were made to fulfill the same functions. Bollards have since evolved into many varieties that are widely employed on roads, specifically in urban areas, as well as outside supermarkets, restaurants, hotels, shops, government buildings and stadiums.
The most frequent type 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 only simple posts, but in addition numerous decorative designs. Some feature square or rectangular cross-sections, but a majority of are cylindrical, sometimes with a domed, angled, or flat cap. They are offered in a number of metallic, painted, and sturdy powder coat finishes.
Removable bollards are utilized 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 they are designed 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 rely on their weight as opposed to structural anchoring to remain in place. They are created to be moved rarely, then simply with heavy machinery for instance a fork-lift.
Bollards generally fall into three varieties of applications:
Decorative Bollards – decorative bollards for architectural and landscaping highlights;
Traffic and Safety Bollards – bollards that offer 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 get 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 manufactured to harmonize with both traditional and contemporary architectural styles. The latter lean toward visual simplicity – often straight-sided posts with a number of reveals close to the top. Styles created 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 actually a distinctive feature; traditional bollard design often includes elaborate decorative finials, whereas contemporary versions frequently feature a simple rounded or slanted top to deter passersby from leaving trash or making use of them for impromptu seating. On the other hand, they may be sometimes made flat and broad specifically to encourage seating. Common decorative bollard materials include iron, aluminum, stainless, and concrete.
Ornamental designs with elaborate detail are usually made of iron or aluminum casting. Aluminum bollards are desirable for applications where weight is a problem, like a removable bollard. Aluminum units tend to be slightly more expensive than iron. For applications where a decorative bollard might be subject to destructive impact, ductile iron is actually 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 usually manufactured by sand-casting – a conventional foundry technique that 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 can machine 100% of the surface after casting to create units with a uniform surface for optimum visual appeal.
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 in contact with a reasonably aggressive environment; petrochemical residues and splashes of diluted road de-icing salts may compromise zuhjvq painted finishes. Factory-applied powder coating – which can be seen on iron, aluminum, and steel – is definitely an especially durable form of painted finish. The application process builds a coating with very consistent coverage. During coating, any bare metal has a tendency 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, decorative bollards manufactured from aluminum might be a better option than iron. When the finish coat is damaged, aluminum oxidizes to a 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 put into the otherwise decorative bollard. For example, common choice 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, a progressively 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.