[nw_arizona_granny]

Straw bale house survives earthquake tests

April 6, 2009
Courtesy University of Nevada, Reno
and World Science staff
It huffed and puffed, but an earth­quake-simula­t­ion ta­ble with a force re­port­ed as 82 tons could­n’t knock down a straw bale house de­signed and built by civ­il en­gi­neer Dar­cey Dono­van.

The 14-by-14-foot (4.3 me­ter) dwell­ing with clay plas­ter walls un­der­went twice the ac­celera­t­ion and shak­ing as recorded at the 1994 Northridge, Ca­lif. earth­quake, the larg­est meas­ured ground ac­celera­t­ion in the world, Dono­van said.

In the last of sev­en in­creas­ingly vi­o­lent tests, the house cracked, swayed and sent out a small cloud of dust and straw — but stayed erect. Dono­van over­saw the tests March 27 at the Uni­ver­s­ity of Ne­vada, Re­no, where she is an alum­na.

She has been build­ing si­m­i­lar homes since 2006 through­out the north­west fron­tier of Pa­ki­stan, in the Him­a­la­ya foothills be­tween the trib­al ar­eas and Kash­mir. A 2005 earth­quake in Kash­mir, meas­ured at mag­ni­tude 7.6, killed 100,000 peo­ple, most of whom per­ished af­ter their flim­sy homes fell on them as they slept.

Dono­van uses bales for struc­tur­al sup­port rath­er than just as in­sula­t­ion as in oth­er straw-bale de­signs.

“Our goal is to get the larg­est num­ber of poor peo­ple in­to earth­quake-safe homes. We want to make it as af­ford­a­ble as pos­si­ble,” Dono­van said. “S­traw bale hous­es are used around the world, but those have posts and beams for sup­port and rely on en­er­gy-intensive ma­te­ri­als, skilled la­bor and com­plex ma­chin­ery, mak­ing it un­af­ford­a­ble for the poor.”

“Our de­sign is half the cost of con­ven­tion­al earth­quake-safe con­struc­tion in Pa­ki­stan,” she added. “The ma­te­ri­als we use — clay soil, straw and grav­el — are readily avail­a­ble; and we uti­lize un­skilled la­bor.”

Part of the trick to Dono­van’s de­sign, she said, is simply pack­ing the straw hard. “We build a small, steel com­pres­sion box, pack it with straw, which is readily avail­a­ble from the Pun­jab Dis­trict, lit­er­ally stomp on it to com­press it, add a lit­tle more, stomp on it a lit­tle more, and then fi­nally use stand­ard farm-type hand jacks to do the fi­nal com­pressing of the bales,” she ex­plained.

“We fill old vegeta­ble sacks with grav­el, like sand­bags, for the founda­t­ion. The bags are fully en­cased, or boxed, in a mor­tar made from clay soil and ce­ment. It’s as low-tech as pos­si­ble.” The build­ings are 80 per­cent more en­er­gy ef­fi­cient than mod­ern con­ven­tion­al build­ings, con­tin­ued Dono­van, whose group al­so trains lo­cal res­i­dents how to build the homes.

While the re­gion lacks build­ing codes, Dono­van and a group she founded, Pa­ki­stan Straw Bale and Ap­pro­pri­ate Build­ing or­gan­iz­a­tion (paksbab.org) are seek­ing an en­dorse­ment from Pa­ki­stan’s newly formed Earth­quake Recon­struc­tion and Re­ha­bilita­t­ion Au­thor­ity.

Source: http://www.world-science.net/othernews/090405_strawbale.htm

[ExSoldier]

Earth sheltered homes aren't merely earthquake proof. They're also: 100% windproof, including Category 5 Hurricane and F5 Tornado. Also 100% fireproof & 100% bulletproof to everything except artillery or air attack. Even floods don't do a lot of damage to the exterior or interior shell of one of these homes.