Introduction
Problem:
High
velocity
flows can
scour the
soil from
under and
around
footings,
threaten
the
building's
structural
integrity,
and even
knock
buildings
off of
their
foundations.
Mitigation
Objective:
Protect
building
facilities
from
damage due
to erosion
caused by
high
velocity
flood
flows.
B.1
Construct
Piling or
New Spread
Footing
Building
foundations
can be
undermined
due to
high
velocity
flows that
scour away
the soils
supporting
the
foundation.
By
constructing
a piling
or new
spread
footing,
the
foundation
is
supported,
thereby
preventing
failure in
subsequent
flooding.
Effectiveness:
Limitations:
- Spread
footings
should
not
be
used
in
a
coastal
environment.
- Area
may
be
inaccessible
to
pile
driving
equipment.
- Pile
driving
may
cause
damage
to
adjacent
facilities.
Considerations:
B.2
Replace
Footing
Materials
To
better
secure
footings
and the
surrounding
material,
replace
lost
footing
material
of soil or
gravel
with
concrete
or grouted
granular
fill. Soil
consolidation
and
settling
caused by
inundation,
or erosion
of the
soil due
to flow
past the
footing,
can often
undermine
the soil
beneath
the
footing,
which
creates a
space
between
the bottom
of the
footing
and the
top of the
soil
beneath
the
footing.
Effectiveness:
Limitations:
- May
not
be
effective
if
future
erosion
cannot
be
controlled,
or,
if
in
the
case
of
inundation,
soil
consolidation
is
not
complete.
|
