Sandbag

Sandbag

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.

Usage

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 seam. After usage, dry sandbags can be stored for future use. Wet bags need to be disposed in a landfill as they may be contaminated by chemicals and fecal matter.cite web|url=http://apnews.myway.com/article/20080626/D91HU2HO0.html|title=Towns left with sandbags|last=Salter|first=Jim|date=2008-06-27|publisher=Associated Press|accessdate=2008-06-27]

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 been used since at least the late 1700s. They 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.Fact|date=June 2008

Sandbags are also used in weight training and put in the trunk of rear wheel drive cars to increase traction in inclement weather.Fact|date=June 2008

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.

ee also

*Hesco bastion
*Sandbagging

References

External links

* [http://www.sandbagsuppliers.co.uk/index.php?Id=20 A Directory of UK local council sandbag policies] .
* [http://www.publicaffairs.water.ca.gov/information/sandbag.cfm California Department of Water Resources and the California Conservation Corps - How to fill and place sandbags] .
* [http://www.nww.usace.army.mil/html/offices/op/em/Library/NWD_Sandbag_Pamphlet.pdf US Army Corps of Engineers Sandbagging pamphlet] (PDF)
* [http://www.nww.usace.army.mil/html/offices/op/em/Library/Flood_Fighting_How_To_Use_Sandbags.pdf US Army Corps of Engineers - How to use Sandbags] {PDF) ( [http://www.nww.usace.army.mil/html/offices/op/em/HowToBag.htm HTML] )


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Look at other dictionaries:

  • sandbag — sand bag , v. To treat harshly or unfairly. [WordNet sense 1] [WordNet 1.6] 2. To hit something or somebody with or as if with a sandbag. [WordNet sense 2] [WordNet 1.6] 3. To protect or strengthen with sandbags; stop up; as, the residents… …   The Collaborative International Dictionary of English

  • sandbag — (n.) 1590, from SAND (Cf. sand) (n.) + BAG (Cf. bag) (n.). The verb sense of pretend weakness is 1970s, extended from poker playing sense of refrain from raising at the first opportunity in hopes of raising more steeply later (1940), which… …   Etymology dictionary

  • sandbag — ► NOUN ▪ a bag of sand, used for defensive purposes or as ballast in a boat. ► VERB (sandbagged, sandbagging) 1) protect or reinforce with sandbags. 2) hit with or as if with a blow from a sandbag. 3) N. Amer. bully. DERIVAT …   English terms dictionary

  • sandbag — [sand′bag΄] n. 1. a bag filled with sand and used for ballast, in military fortifications, for levee protection against floods, etc. ☆ 2. a small, narrow bag filled with sand and used as a bludgeon vt. sandbagged, sandbagging 1. to place sandbags …   English World dictionary

  • sandbag — sand bag , n. A bag filled with sand; small sandbags may be used as a weapon, or larger ones to build walls or as ballast; as, they kept the flooding river from the area by buiding a temmporary dike out of sandbags. [WordNet 1.6] …   The Collaborative International Dictionary of English

  • sandbag — I UK [ˈsæn(d)ˌbæɡ] / US noun [countable] Word forms sandbag : singular sandbag plural sandbags a bag that is filled with sand and put in a pile with other sandbags to protect a place from flood water or explosions II UK [ˈsæn(d)ˌbæɡ] / US verb… …   English dictionary

  • sandbag — /ˈsændbæg/ (say sandbag) noun 1. a bag filled with sand, used in fortifications, levees, as ballast, etc. 2. a small bag filled with sand, used as a weapon. –verb (t) (sandbagged, sandbagging) 3. to furnish with sandbags: *The top of the mound… …  

  • sandbag — 1. tv. to force someone to do something. □ I don’t want to have to sandbag you. Please cooperate. □ Don’t let them sandbag you into buying something you don’t need. 2. tv. to deceive someone; to fool someone about one’s capabilities. □ Don’t let… …   Dictionary of American slang and colloquial expressions

  • sandbag — sandbagger, n. /sand bag /, n., v., sandbagged, sandbagging. n. 1. a bag filled with sand, used in fortification, as ballast, etc. 2. such a bag used as a weapon. v.t. 3. to furnish with sandbags. 4. to hit or stun with a sandbag. 5. Informal. a …   Universalium

  • sandbag — [[t]sæ̱ndbæg[/t]] sandbags, sandbagging, sandbagged 1) N COUNT A sandbag is a cloth bag filled with sand. Sandbags are usually used to build walls for protection against floods or explosions. 2) VERB To sandbag something means to protect or… …   English dictionary

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