There are many bridges, transmission towers and other structures built on driven timber piles. As they age, it is often difficult to maintain the piles as they are costly to excavate or in some cases excavation is impractical. Transpower has a number of 1930-1960's era transmission line towers built on timber piled foundations. Generally these are located at or close to river or other waterway crossings. The piles are invariably Australian hardwoods, typically ironbark, black butt or spotted gum. The foundations usually consist of three timber piles on each corner of the tower, a total of 12 piles per tower. Each group of three piles is capped with a concrete block approximately 2 m deep, which in turn is bolted to the bottom of the tower leg. (Photos 1 and 2)
展开▼
