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# I need help guide for a mechanical project related to mechanics and design

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Hi Mechanical Engineering people this is my first activity here ,im a student from palestine .

i have a project in mechanics of materials subject...it is a project of signboard with two legs and we should design it so that it gives us good saftey factor ,not all dimensions are give some are given and other should be identified  to give us a good design .

i have a problem in starting this project

the project mark is just 10 marks from the whole course so i think it will be simple

i want just to have an idea of what things should i do, like how to start and what steps i must take ...can any one help me in that please?

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Wind load could be calculated from ASCE 7 or EN 1991-1-4 or other relevant codes.

The wind load (essentially pressure) multiply by effective area (5m x 2m of signboard in your drawing) to get a working wind force.

Multiply this with 3 m height, to get working moment at the base.

Let say using structural steel with yield strength of 240 MPa, safety factors 3, you get allowable working stress of 80 MPa.

Check the cross-sectional properties (second moment area, radius, thickness) to get this allowable working stress.

Stress = M x r / I

For a thin cylinder, I = pi x r^3 x thickness.

Then you get the dimension needed for the pole/support.

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First , thank you very much for replying and explaining

As for the first step what the loads that i must find ...

I have to take moment and get reactions from the wieght and wind force  is there any forces should be taken here ?...

Could you please explain this static part related to get the reactions in the first step ...how to use it in these problem  ?

The safety factor ...should i suppose a value for it from me or it must be calculated from the yield strength and stresses?