A vertical pole of aluminum is fixed at the base and pulled at the top by a cable having a tensile force T (see figure). The cable is attached at the outer edge of a stiffened cover plate on top of the pole and makes an angle α = 20° at the point of attachment. The pole has length L= 2.5 m and a hollow circular cross section with outer diameter d2 = 280 mm and inner diameter d1= 220 mm. The circular cover plate has diameter 1.5d2.
Determine the allowable tensile force Tallow in the cable if the allowable compressive stress in the aluminum pole is 90 MPa.
