Snap through — where it appears
Named by 2 essays across one field — each of them below, with the objects they name alongside it.
The roof that jumps
Every stability failure in this collection so far has been a bifurcation — a straight thing discovering it can be bent. A shallow frame does something else entirely. It stays perfectly symmetric, deforms steadily, and at some point the load it can carry starts to fall while it is still moving in the direction it was pushed.
The arch that leans instead of squashing
A masonry arch is asked whether a line of thrust fits inside it. A steel rib is asked a different question entirely: it is a column carrying an axial force along its whole length, and the mode it buckles in puts one half up and the other half down while the crown moves sideways.
Named alongside it
The objects these essays reach for when they reach for this one.
BucklingAntisymmetric modeArchBifurcationBracingCritical loadEffective lengthEigenvalueEquilibrium pathGeometric nonlinearityGeometric stiffnessLimit point