Lattice tower
A lattice tower or truss tower is a freestanding vertical framework tower. This construction is widely used in transmission towers carrying high voltage electric power lines, in radio masts and towers (a self-radiating tower or as a support for aerials) and in observation towers. 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 lines. Lattices of triangular (3-sided) cross-section are most common, particularly in North America. Square (4-sided) lattices are also widely used and are most common in Eurasia. Lattice towers are 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 Mühlacker, Germany. It had a height of 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