Question

so mm Figure 2: A traffic lighr Figure 3: Traffic light's column cross-section e aim to study the maxi section of the column is illustrated in figure 3. The column is imum light weight allowed on the traffic light's column illustrates in figure 2. 70 GPa and a Poisson ratio v made from aluminum having a modulus ofelasticity E heoremm, find the allowable mass of the light if the vertical deflection of the consider in this seetion the curved part as baving a large 1. 5 m and therefore approximate the curved beam by a straight one. Do light should not exceed 0.04 m. You may radius of curvature lect the contribution of the shear force in the total energy of the sys 320 MPa, find the allowable mass of the light to avoid ing a maximum yielding stress ơyp yieldi ng. Use a factor of safety equal to 2 in this section. Also, in this section, use the curved beam formula to compute the normal stress in the curved beam part. c) Wh at is the maximum mass of the light to avoid buekling in the vertical part of the column? Use the AISC recommendations if200 and a factor of safety of 3 if> 200 d) Deduce from the previous parts the maximum allowable mass of the light.

Answer 1

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