Introduction
The behavior of structural members subjected to blast loads,
e.g., in the case of boiler explosion or vehicle bomb attack,
is an important concern in the assessment of structural safety
in such adverse scenarios. For beams subjected to blast loads
that are characterized by high magnitude pressure and short
duration distributed along the length, it has been observed
experimentally that failure is often initiated by direct shear
failure at the supports and occurs shortly after load
application, although diagonal shear failure along the beam
is also observed sometimes. Such failure phenomenon can
be explained based on Timoshenko beam theory where shear
deformation and rotary inertia are accounted for, resulting in
a model with a finite shear wave speed. Characteristic of
wave propagation, the numerical solution demands fine mesh
and small sampling time for accurate representation of waves
that are responsible for initial built-up of stresses. As a result,
the wave propagation problem is often solved numerically
for an isolated beam or connections because the analysis of
the whole structure is computationally prohibitive, if the
wave characteristics are to be captured adequately. An
understanding of the wave propagation phenomenon in
building up the internal shear and moment during blast load
events provides insights and opportunity for separating the
wave propagation problem from the global analysis of the
whole structure, thus permitting numerical analysis to be
carried out with less computational efforts.

Authors:

S. K. Au (cskau@ntu.edu.sg)
K. H. Tan (ckhtan@ntu.edu.sg)
K. W. Wei (p143663095@ntu.edu.sg)


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