| dc.description.abstract | Although actual structural members are subjected
to multi-axial loads, material properties are derived
from expurim ntal works in a single-direotion load
application. Thus analysis of materials under
multi-axial loads helps to understand the actual
situation prevailing in structural members in
operation.
In this thesis the Griffith's fracture criterion
and linear elastic fracture mechanics are used to
predict the stress needed to rupture a biaxially
loaded specimen containing a central crack. The
analytical results suggest dependence of the critical
strocc on oombLna Ll.on n 01' I'ol nson 's rat i.o,
biaxiality, crack inclination and. on whether the
state of plane stress or plane strain prevails.
Experimental work performed on mild steel specimens
for the horizontal crack (a=90o) indicate increased
critical stress with increasing biaxiality whereas
the effect on PVC specimens with the same crack
inclination was the revere and this agreed ~ith the
predictions of the analytical results.
, The experimental work also included fatigue
tests on the steel specimens while different
horizontal loads were applied. The fatigue crack
propagation data indicated dependence of the FCG rate
on the applied horizontal load such that there is a
higher crack growth rate with higher horizontal
loads. | en |
