題組內容

3. A pressurized steel tank is constructed with a helical weld that makes an angle α = 55° with the longitudinal axis (Fig. 2). The tank has radius r = 0.6 m, wall thickness t = 18 mm, and internal pressure p = 2.8 MPa. Also, the steel has modulus of elasticity E = 200 GPa and Poisson’s ratio = 0.30. Determine the following quantities for the cylindrical part of the tank.

(c)The circumferential and longitudinal strains.