Koiter's imperfection sensitivity theory

Summary

Koiter's theory is the asymptotic analysis of elastic structures near the point where they buckle. It describes the initial post-buckling path of the perfect structure by a few coefficients. From them it predicts how much small geometric imperfections lower the maximum load. It explains why thin cylindrical shells under axial compression fail far below their classical buckling load while flat plates do not. W. T. Koiter set it out in his Delft doctoral thesis of 1945.