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huangyhg 2009-09-07 01:26 PM

asce7 ice loads
 
asce7 ice loads
i am designing the foundation for a minor tower. the specifications included design of ice loads from asce7-02. when i use eqn 10-1 to calculate the area it seems excessive. it takes a length times a width (a rectangle) and then multiplies it by pi. i understand pi*d^2/4 as an area but the division by 4 is missing. i checked asce7-05 but the eqn is the same. i do not have a copy of ansi/eia/tia222. does it have a comparable eqn? asce7 already doubles the ice thickness to go from a "radius" to "diameter" type calculation. thanks
the wind area is the projected area facin wind.(not the cross vsection)
it seems that ice would form over the surface area, not the cross sectional area. to get surface area, i would expect you to take length times width times 4 for a rectangular section. pi is less than 4. does it seem so unreasonable then?
btw an 800' tower recently came down due to combined high wind and ice.this belonged to


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