Dictionary Definition
sandbagger n : someone who deceives you about his
true nature or intent in order to take advantage of you
Extensive Definition
A sandbag (floodbag) is a sack made of burlap, polypropylene or other
materials that is filled with sand or soil and used for such purposes as
flood control, military
fortification,
shielding glass windows in war zones and
ballast.
Advantages are that burlap and sand are
inexpensive, and that the bags can be brought in empty and filled
with local sand or soil.
Sandbags may be used during emergencies when
rivers threaten to overflood, or a levee or dike
is damaged. They may also be used in non-emergency situations (or
after an emergency) as a foundation for new levees, or other
water-control structures. Sandbags are not always an effective
measure in the event of flooding because water will eventually seep
through the bags and finer materials, like clay, may leak out
through the seams.
The military uses sandbags for field fortifications, or as a
temporary measure to protect civilian structures. Because burlap
and sand are inexpensive, large protective barriers can be erected
cheaply. The friction created by moving soil or sand grains and
multiple tiny air gaps makes sandbags an efficient dissipator of
explosive blast. The
dimensions and weight of sandbags used in fortification are
carefully calculated so that the bags can be interlocked like
brickwork and are not
too heavy to lift and move around. They may be laid in excavated
defences as revetment, or as free-standing walls above ground where
excavations are impractical. As plain burlap sandbags deteriorate
fairly quickly, sandbag structures that are meant to remain in
place for a long time may be painted with a portland
cement slurry to
reduce the effects of rot
and abrasion. Cotton Ducking sandbags last considerably longer than
burlap and are hence preferable for long-term use. However, the
vast majority of sandbags used by modern militaries and for flood
prevention are made of circular woven polypropylene. The easy
availability to military personnel, size and construction of the
bags has also led to the use of sandbags as makeshift hoods for
prisoners
of war.
Sandbags are also used for disposable ballast in
gas
balloons, and as counterweights for
theatre
sets.
Sandbags have traditionally been filled manually
using spades. Since the
1990s, machine-filling has become more common, which allows the
work to be done more quickly and efficiently.
Other uses
"Sandbag" can also refer to a crude weapon consisting of a small bag
filled with sand for use as a cudgel typically by criminals, or to the act of
striking a person on the head with such a weapon. This usage is
obsolescent in normal speech, appearing mainly in legal codes.
However the verb form is extended metaphorically in several
slang expressions.
Sandbags are also used in weight
training and put in the trunk of rear wheel
drive cars to increase traction in inclement weather.
In games and various kinds of adversarial
settings, the term sandbagging refers to the
practice of purposely placing oneself in a weaker position so as to
give the deceptive impression that one is less skilled than one
truly is.
External links
See also
sandbagger in German: Sandsack
sandbagger in Dutch: Zandzak
sandbagger in Japanese: 土嚢
sandbagger in Swedish:
Sandsäck