This paper presents experimental studies and analyses on mild steel tu
be specimens that are indented by a rigid but blunt wedge-shaped inden
ter at the midspan. Three different support conditions are investigate
d: simply supported ends, fully fixed ends and the whole tube lying on
a fiat surface. A test program was carried out to determine the colla
pse loads and energy-absorbing capabilities of tubes of different size
s. Based on a dimensional argument and the experimental plots, empiric
al closed-form expressions have been established for the collapse load
s and energy, Generally, good agreement has been obtained between the
empirical equations and the experimental data. The empirical equations
can provide an important first-hand guide for design engineers and an
alysts in this subject area.