| Abstrakt: |
The so-called Lamé formula, either in its true form, or in an equivalent but less complex modified form, is advanced as the most suitable formula for the design of pipe that is stressed in the elastic range by internal pressure. In the creep range, the use of the Bailey-Nadai formula is proposed, and it is shown that the so-called Lamé formula in either form is a good approximation of the Bailey-Nadai formula. In the selection of these two formulas, the so-called Lamé formula and the Bailey-Nadai formula, an examination has been made of the common, average (membrane), Barlow, Clavarino, Guest, Beltrami, and von Mises formulas. The origin and meaning of all of these expressions are discussed. Their significance for design purposes is explained, and their relationship to the so-called Lamé formula is demonstrated. The need for additional pure shear experimental data on creep and on stress rupture is emphasized. |
