<s>
In	O
statics	O
and	O
structural	O
mechanics	O
,	O
a	O
structure	O
is	O
statically	B-Algorithm
indeterminate	I-Algorithm
when	O
the	O
static	O
equilibrium	O
equations	O
force	O
and	O
moment	O
equilibrium	O
conditions	O
are	O
insufficient	O
for	O
determining	O
the	O
internal	O
forces	O
and	O
reactions	O
on	O
that	O
structure	O
.	O
</s>
<s>
The	O
structure	O
is	O
therefore	O
classified	O
as	O
statically	B-Algorithm
indeterminate	I-Algorithm
.	O
</s>
<s>
To	O
solve	O
statically	B-Algorithm
indeterminate	I-Algorithm
systems	O
(	O
determine	O
the	O
various	O
moment	O
and	O
force	O
reactions	O
within	O
it	O
)	O
,	O
one	O
considers	O
the	O
material	O
properties	O
and	O
compatibility	O
in	O
deformations	O
.	O
</s>
<s>
If	O
the	O
support	O
at	O
is	O
removed	O
,	O
the	O
reaction	O
cannot	O
occur	O
,	O
and	O
the	O
system	O
becomes	O
statically	B-Algorithm
determinate	I-Algorithm
(	O
or	O
isostatic	O
)	O
.	O
</s>
<s>
Descriptively	O
,	O
a	O
statically	B-Algorithm
determinate	I-Algorithm
structure	O
can	O
be	O
defined	O
as	O
a	O
structure	O
where	O
,	O
if	O
it	O
is	O
possible	O
to	O
find	O
internal	O
actions	O
in	O
equilibrium	O
with	O
external	O
loads	O
,	O
those	O
internal	O
actions	O
are	O
unique	O
.	O
</s>
<s>
Mathematically	O
,	O
this	O
requires	O
a	O
stiffness	B-Algorithm
matrix	I-Algorithm
to	O
have	O
full	O
rank	O
.	O
</s>
<s>
A	O
statically	B-Algorithm
indeterminate	I-Algorithm
structure	O
can	O
only	O
be	O
analyzed	O
by	O
including	O
further	O
information	O
like	O
material	O
properties	O
and	O
deflections	O
.	O
</s>
