Question

A tower used in an electrical substation supports a power line which exerts a horizontal tension of T = 500 lb on each side truss of the tower as shown. Determine the force in members BC, CM, and LM of a side truss and indicate whether the members are in tension or compression.After a Recent cold spell, it has been seen that substantial amounts of snow and ice have accumulated on top of the structure. The top member of the tower has a solid platform on which this collects. It has been estimated that an additional meter in depth has been observed.

New Snow = 50-70kg/m3

Damp New Snow = 100 - 200 kg/m3

Settled Snow = 200 - 300 kg/m3

Deep hoar = 100 - 300 kg/m3

Wind Packed Snow = 350 - 400 kg/m3

Firn (granular) = 400 - 830 kg/m3

Very Wet = 700 - 800 kg/m3

Glacier Ice = 830 - 917 kg/m3

New designs have stipulated Aluminium rather than Steel to cut down weight and cost. Calculate if the structure will be substantial enough and up to the job. If a similar structure was installed in a sub-saharan country where temperatures regularly exceed 40 degC would the temperature coefficient of Aluminium cause any problems?

500 lb G H 20 ft F 20 ft E 20 ft D 20 ft 20 ft в ИТЕС 20 ft А 15ft н

Answer 1

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