The prominence of bollards has dramatically increased in the past decade because of heightened fears about security. These are a simple, practical, and cost-effective way of erecting anti-ram perimeter defense without developing a visual sense of a fortified bunker. Bollards are popular for traffic direction and control, and in purely decorative applications. However, safety bollards for sale can offer many characteristics beyond security. They can be used for purely aesthetic purposes, functioning as landscaping elements. Bollards can make visible boundaries of a property, or separate areas within sites. They can control traffic and they are often organized 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 inform 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 our own building exteriors and surrounding areas. Bollards can incorporate other functions such as lighting, surveillance cameras, bicycle parking or even seating. Decorative bollards are made in a number of patterns to harmonize with a wide range of architectural styles. The prevalence of the most common form 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.
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 in use today. An average marine bollard is manufactured in cast iron or steel and shaped somewhat just like a mushroom; the enlarged top is made to prevent mooring ropes from slipping off.
Today, the term bollard also describes a number of structures used on streets, around buildings, as well as in landscaping. In accordance with 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. When the availability of former cannons was utilized up, similarly shaped iron castings were designed to match the same functions. Bollards have since become 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 form of bollard is fixed. The simplest is surely an unaesthetic steel post, about 914 to 1219 mm (36 to 48 in.) above-grade. Specially manufactured bollards include not merely simple posts, but also a wide variety of decorative designs. Some feature square or rectangular cross-sections, but most are cylindrical, sometimes having a domed, angled, or flat cap. They come in a number of metallic, painted, and sturdy 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 frequently needed, and are designed so the bollard can be simply collapsed to ground level and quickly re-erected. Both retractable units may 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 as opposed to structural anchoring to stay in place. They are created to be moved rarely, and after that simply with heavy machinery for instance a fork-lift.
Bollards generally fall into three types of applications:
Decorative Bollards – decorative bollards for architectural or landscaping highlights;
Traffic and Safety Bollards – bollards which provide asset and pedestrian safety, along with 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 also 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 close to the top. Styles created to match various historic periods will often have more elaborate shapes and surface details. Included in this are 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 come with a simple rounded or slanted top to discourage passersby from leaving trash or making use of them for impromptu seating. On the other hand, these are 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 frequently manufactured from iron or aluminum casting. Aluminum bollards are desirable for applications where weight is an issue, for instance a removable bollard. Aluminum units tend to be slightly 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 frequently manufactured by sand-casting – a regular foundry technique that is economical and well-fitted to objects this size. However, sand-cast objects frequently bear surface irregularities that tend to leave the finished product less appealing to the eye. If high-finish consistency is desired, seek a manufacturer which will machine 100% in the surface after casting to produce units with a uniform surface for maximum appearance.
Finish is a crucial consideration in a decorative bollard, from functional along with 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 relatively aggressive environment; petrochemical residues and splashes of diluted road de-icing salts may compromise some painted finishes. Factory-applied powder coating – which is on iron, aluminum, and steel – is surely an especially durable kind of painted finish. The application form 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 finish gives it additional toughness and abuse resistance.
In applications where greater physical abuse is predictable, bollard covers made of aluminum may be a better option than iron. If the finish coat is damaged, aluminum oxidizes to a color which is generally more acceptable than the red rust produced by iron. Aluminum and stainless-steel can also be found in a quantity of bare metal finishes. Functionality can be put into the otherwise decorative bollard. As an example, common option is the chain eye – linking several bollards with chain, making a simple traffic direction system. A large metal loop or arm on the side in the post allows parking and locking of bicycles, a progressively popular choice as more people seek alternative green transportation. Bollards may 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, in addition to security and safety. The very first function is achieved from the visual presence in the bollards, and to some degree by impact resistance, although, within these applications visual deterrence is 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 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 – like wheelchairs or shopping carts – but prevents the passage of cars. Such installations are often 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 for a site, care must be taken to avoid locating them where they will 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 line of bollards linked with a chain presents a visual cue never to cross the boundary, though it could be easy enough for any pedestrian to travel over or underneath the chain should they choose. Bollards designed to direct traffic are occasionally 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 frequently placed on the corners of buildings, or flanking lamp-posts, public phones, fire hydrants, gas pipes as well as other installations that ought to be protected against accidental contact. A bollard at 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 are employed where U-turns and tight-radius turns are frequent. This type of usage is especially common at corners where vehicle drivers often misestimate turns, and pedestrians are specifically near to the roadbed waiting to cross. In a few 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 potency of also a low post at stopping cars.