pipe under external pressure

[giorgiobello]

i want to design thickness of an empty buried tank.Can anyone give me some formulas,please?
Also formulas to design a pipe under external pressure are well accepted.I am making a preliminar fast design so don't worry if you don't have so detailed formulas
thank you all from Italy

 

[HenryBell]

To start, you might check ASME B31.3, Section 304.1.3. BPV Code, Section VIII, Division 1 is a great resource as well.