Re-design the structure in given example avoiding thick

Question

Re-design the structure in given Example avoiding thick clusters of plies and taking into account in-situ strength. Use t_t = 1.2 mm and ν₂₃ = 0.38.

Example

Design a cylindrical pressure vessel with diameter d = 4 m, internal pressure p = 3.0 MP a, with a COV C_p = 0.10 to achieve a reliability R_e = 0.95 with respect to the burst pressure. Use a coordinate system on the surface of the cylinder with the y-axis oriented in the hoop direction and the x-axis oriented along the length. Assume that the strength reported in Figures 1 - 2 has a variability represented by COV C_F = 0.12.