A fence is a structure that encloses an area, typically outdoors, and is usually constructed from posts that are connected by boards, wire, rails or netting. A fence differs from a wall in not having a solid foundation along its whole length.
Barbed wire, also known as barb wire, is a type of steel fencing wire constructed with sharp edges or points arranged at intervals along the strands. Its primary use is the construction of inexpensive fences, and it is also used as a security measure atop walls surrounding property. As a wire obstacle, it is a major feature of the fortifications in trench warfare.
Barbed tape or razor wire is a mesh of metal strips with sharp edges whose purpose is to prevent trespassing by humans. The term "razor wire", through long usage, has generally been used to describe barbed tape products. Razor wire is much sharper than the standard barbed wire; it is named after its appearance but is not razor sharp. The points are very sharp and made to rip and snag clothing and flesh.
In agriculture, fences are used to keep animals in or out of an area. They can be made from a wide variety of materials, depending on terrain, location and animals to be confined. Most agricultural fencing averages about 4 feet (1.2 m) high, and in some places, the height and construction of fences designed to hold livestock is mandated by law.
In architecture and structural engineering, a space frame or space structure is a rigid, lightweight, truss-like structure constructed from interlocking struts in a geometric pattern. Space frames can be used to span large areas with few interior supports. Like the truss, a space frame is strong because of the inherent rigidity of the triangle; flexing loads are transmitted as tension and compression loads along the length of each strut.
Ultrasonic welding is an industrial process whereby high-frequency ultrasonic acoustic vibrations are locally applied to work pieces being held together under pressure to create a solid-state weld. It is commonly used for plastics and metals, and especially for joining dissimilar materials. In ultrasonic welding, there are no connective bolts, nails, soldering materials, or adhesives necessary to bind the materials together. When used to join metals, the temperature stays well below the melting point of the involved materials, preventing any unwanted properties which may arise from high temperature exposure of the metal.
A mesh is a barrier made of interlaced strands of metal, fiber or other flexible or ductile materials. A mesh is similar to a web or a net in that it has many interwoven strands.
An electric fence is a barrier that uses electric shocks to deter people and other animals from crossing a boundary. The voltage of the shock may have effects ranging from discomfort to death. Most electric fences are used for agricultural fencing and other forms of non-human animal control, although they are also used to protect high-security areas such as military installations or prisons, where potentially-lethal voltages may be used. Virtual electric fences for livestock using GPS technology have also been developed.
A chain-link fence is a type of woven fence usually made from galvanized or linear low-density polyethylene-coated steel wire. The wires run vertically and are bent into a zigzag pattern so that each "zig" hooks with the wire immediately on one side and each "zag" with the wire immediately on the other. This forms the characteristic diamond pattern seen in this type of fence.
A pitch or a sports ground is an outdoor playing area for various sports. The term pitch is most commonly used in British English, while the comparable term in Australian, American and Canadian English is playing field or sports field.
A chain is a serial assembly of connected pieces, called links, typically made of metal, with an overall character similar to that of a rope in that it is flexible and curved in compression but linear, rigid, and load-bearing in tension. A chain may consist of two or more links. Chains can be classified by their design, which can be dictated by their use:
Temporary fencing is a free standing, self-supporting fence panel. The panels are held together with couplers that interlock panels together making it portable and flexible for a wide range of applications. A common type of temporary fencing is Heras fencing.
A steel fence post, also called a T-post, a Y-post, or variants on star post, is a type of fence post or picket. They are made of steel and are sometimes manufactured using durable rail steel. They can be used to support various types of wire or wire mesh. The end view of the post creates an obvious T, Y, or other shape. The posts are driven into the ground with a manual or pneumatic post pounder. All along the post, along the spine, there are studs or nubs that prevent the barbed wire or mesh from sliding up or down the post. They are generally designated as 1.01, 1.25 or 1.33, referring to the weight in pounds per lineal foot. They are commonly painted with a white tip on top; white improves the visibility of the fence line. When driving the post with a post pounder the white top paint is a visual means to ensure the user doesn’t raise the pounder too high while pounding. Raising the pounder too high allows it to lean towards the user and could lean to striking them in the head.
A swimming pool fence is a type of fence placed around swimming pools, to create a passive barrier to restrict the access of small children to the swimming pool. Swimming pool fences must have a self-closing and self-latching gate/s to be compliant to most countries' laws and codes.
Mechanical screening, often just called screening, is the practice of taking granulated or crushed ore material and separating it into multiple grades by particle size.
Pallet rack is a material handling storage aid system designed to store materials on pallets. Although there are many varieties of pallet racking, all types allow for the storage of palletized materials in horizontal rows with multiple levels. Forklift trucks are usually required to place the loaded pallets onto the racks for storage. Since the Second World War, pallet racks have become a ubiquitous element of most modern warehouses, manufacturing facilities, retail centers, and other storage and distribution facilities. All types of pallet racking increase storage density of the stored goods. Costs associated with the racking increases with increasing storage density.
Demarcation of a perimeter, when the protection of assets, personnel or buildings is required, is normally affected by the building of a perimeter fence system. The level of protection offered varies according to the threat level to the perimeter. Different types of perimeter fencing include:
The inner German border was a complex system of interlocking fortifications and security zones 1,381 kilometres (858 mi) long and several kilometres deep, running from the Baltic Sea to Czechoslovakia. The outer fences and walls were the most familiar and visible aspect of the system for Western visitors to the border zone, but they were merely the final obstacle for a would-be escapee from East Germany. The complexity of the border system increased steadily until it reached its full extent in the early 1980s. The following description and the accompanying diagram describe the border as it was around 1980.
Welded wire mesh, or welded wire fabric, or "weldmesh" is an electric fusion welded prefabricated joined grid consisting of a series of parallel longitudinal wires with accurate spacing welded to cross wires at the required spacing.
This page is a glossary of Prestressed concrete terms.
