Electric angle steel tower
With the development of the times, power towers can be classified according to the construction materials, structural types and use functions. According to different products, their uses are also different. Let’s briefly explain their classification and main uses:
1. According to the construction materials, it can be divided into wood structure, steel structure, aluminum alloy structure and reinforced concrete structure tower. Due to its low strength, short service life, inconvenient maintenance and limited by wood resources, wooden tower has been eliminated in China.
Steel structure can be divided into truss and steel pipe. Lattice truss tower is the main structure of EHV transmission lines.
Because of the high cost, aluminum alloy tower is only used in mountainous areas where transportation is very difficult. The reinforced concrete poles are poured by centrifuge and cured by steam. Its production cycle is short, the service life is long, the maintenance is simple, and can save a lot of steel
2. According to the structure, it can be divided into two types: self supporting tower and guyed tower. Self supporting tower is a kind of tower which is stable by its own foundation. Guyed tower is to install symmetrical guy wire on the tower head or body to support the tower stably, and the tower itself only bears vertical pressure.
As the guyed tower has good mechanical properties, it can resist the impact of storm attack and line break, and its structure is stable. Therefore, the higher the voltage is, the more guyed tower will be used.
3. According to the function, it can be divided into bearing tower, linear tower, transposition tower and long span tower. According to the circuit number of the transmission line erected by the same tower, it can also be divided into single circuit, double circuit and multi circuit tower. The bearing tower is the most important structural link on the transmission line.
4. Foundation type of line tower: the hydrogeological conditions along the transmission line vary greatly, so it is very important to select the foundation form according to local conditions.
There are two types of foundations: cast-in-situ and precast. According to tower type, underground water level, geology and construction method, cast-in-place foundation can be divided into undisturbed soil foundation (rock foundation and excavation foundation), explosion expanding pile foundation and cast-in-place pile foundation, and ordinary concrete or reinforced concrete foundation.
The prefabricated foundation includes chassis, chuck and stay plate for electric pole, prefabricated concrete foundation and metal foundation for iron tower; the theoretical calculation of anti uplift and anti overturning of foundation is being studied and treated by various countries according to different foundation forms and soil conditions, so as to make it more reasonable, reliable and economical.