Editing Lattice tower (section)

{{Short description|Freestanding framework tower}}
[[File:Tour Eiffel Wikimedia Commons.jpg|thumb|The [[Eiffel Tower]], measuring {{cvt|330|m}} from base to tip, is perhaps the most famous example of a lattice tower. It was built in 1889, and was the tallest man-made structure in the world until 1930.]]

A '''lattice tower''' or '''truss tower''' is a freestanding vertical [[latticework|framework]] [[tower]]. This construction is widely used in [[transmission tower]]s carrying high-voltage electric [[power line]]s, in [[radio masts and towers]] (a self-radiating tower or as a support for [[Antenna (radio)|aerials]]) and in [[observation tower]]s. Its advantage is good [[shear strength]] at a much lower weight than a tower of solid construction would have as well as lower wind resistance.

In [[structural engineering]], the term ''lattice tower'' is used for a [[freestanding structure]], while a ''lattice mast'' is a [[guyed mast]] supported by [[guy line]]s. Lattices of triangular (three-sided) cross-section are most common, particularly in North America. Square (four-sided) lattices are also widely used and are most common in Eurasia. A lattice towers is often designed as either a [[space frame]] or a [[hyperboloid structure]].

Before 1940, they were used as radio transmission towers especially for short and medium wave. Occasionally lattice towers consisting of wood were utilized. The tallest wooden lattice tower was at [[Transmitter Mühlacker|Mühlacker]], Germany. It had a height of {{convert|190|m|ft}} and was built in 1934 and demolished in 1945. Most wood lattice towers were demolished before 1960. In Germany, the last big radio towers consisting of wood were the transmission towers of the [[Golm transmitter]] and the [[transmitter Ismaning]]. They were demolished in 1979 and 1983 respectively.

The tallest free-standing lattice tower is the [[Tokyo Skytree]], with a height of {{convert|634|m|ft}}. The [[Petronius Compliant Tower]] is the tallest supported lattice tower at {{convert|640|m|ft}}, being partially submerged. The city most renowned for lattice towers is [[Cincinnati]], Ohio, which features four towers above {{convert|274|m|ft}} in height. Tokyo is the only other city in the world that has more than one above that height.

The majority of the tallest steel lattice towers in the world are actually built in water and used as oil platforms. These structures are usually built in large pieces on land, most commonly in Texas or Louisiana, and then moved by barge to their final resting place. Since a large portion of these towers is underwater, the official height of such structures is often held in dispute. The steel lattice truss for these structures, known as jackets in the oil industry, are typically far more robust and reinforced than their land-based counterparts, sometimes weighing more than 50,000 tons as is the case for the [[Bullwinkle Platform|Bullwinkle]] and [[Baldpate (oil platform)|Baldpate]] platforms, whereas tall (above 300 m) land-based lattice towers range from a high of 10,000 tons as is the case in the [[Eiffel Tower]] to as low as a few hundred tons. They are built to a higher standard to support the weight of the oil platforms built on top of them and because of the forces to which they are subjected. As a result, the cost to build these structures can run into the [[Petronius (oil platform)|hundreds of millions]]. These costs are justified due to the resulting oil and gas revenues, whereas land-based towers have a much lower stream of revenue and therefore the capital costs of towers are typically much less.

[[File:Tokyo Sky Tree 2012 Ⅳ.JPG|thumb|[[Tokyo Skytree]], the tallest lattice tower in the world since its completion in 2012]]
[[File:Tokyo Tower 20060211.JPG|thumb|The [[Tokyo Tower]] was the tallest lattice tower in the world for 16 years, from 1957 to 1973, and remains the tallest four-sided lattice tower.]]
[[File:Witi tv tower shorewood wisconsin.JPG|thumb|The [[WITI TV Tower]] is the tallest lattice tower in the United States and the tallest three-sided lattice tower in the world.]]
[[File:DragonTower.jpg|thumb|[[Dragon Tower]], the tallest observation and radio lattice tower in China, features a solid core, the most common design for tall lattice towers built in China.]]
[[File:Tamar jacket on H851.JPG|thumb|A {{cvt|243|m}}-long fixed steel jacket (lattice) oil platform]]
[[File:BBlaunch.jpg|thumb|A {{cvt|250|m}}-long section of the Benguela-Belize Lobito-Tomboco Platform, which accounts for only about half the overall height of the structure]]