prabalit kankreet

prabalit kankreet (angreji:Reinforced concrete), vah kankreet hota hai jismein, kankreet ko tanaav ki sthiti mein bhi majaboot rakhane ke liye prabalan chhadon (baar), prabalan gridon, plate ya tantuon ko kankreet mein shaamil kiya jaata hai. kankreet sanpeedn mein majaboot lekin tanaav mein kamjor hota hai iseeliye prabalan ki prakriya ke dvaara ise tanaav mein bhi majabooti pradaan ki jaati hai. kankreet ka aavishkaar ek fraanseesi maali Joseph moniyr dvaara san 1849 mein kiya gaya tha aur 1867 mein ise peteint praapt hua. lohe ya ispaat ke dvaara prabalit kankreet lauh ya fero kankreet kahalaata hai. kankreet ko prabalit karne mein prayukt anya saamagriyaan kaarbanik aur akaarbanik tantu ya alag alag roopon mein inka mishran ho sakta hai. tanaav mein kankreet ka pratibl vifalta itni kam hoti hai ki prabalan saamagri ka kaarya is avastha mein iske toote huye khandon ko ek saath pakade rahana bhi hota hai.

ek majaboot, namaneeya aur tikaaoo nirmaan ke liye prabalan saamagri mein nimnalikhit gun hone chaahiye:

  • uchch saamarthya
  • uchch tanan pratibl
  • krankreet ke saath achha bandh (bond)
  • ooshmeeya anukoolata
  • kankreet vaataavaran mein sthaayitv

audyogik raashtron mein, lagbhag sabhi kankreet nirmaan prabalit hote hain.

anukram

itihaas

aar.si.si. ka imaarat nirmaan mein prayukt padaarth roop mein pratham prayog san 1864 mein, William baautalaind vilkinsan dvaara nirmit nyookaisal, sanyukt raajashaahi ke ek makan mein hua tha. 1887 mein A.ji.vaayass dwaar aar.si.si. par ek pustak prakaashit hone ke saath hi, ek jarman company vaayas end fritaig ki sthaapana 1875 mein hui. Europe mein, unke mukhya pratidvandi frainkois hainnibeek ki sansth thi, jo 1892 man sthaapit hui.

ek aar.si.si pranaali ko sanyukt raajya America ke thaidas haayat ne 1878 mein peteint (poornadhikaar ya prayogaadhikaar) surakshit kara liya tha. you.S mein nirmit pratham aar.si.si. imaarat thi 1893 mein bani paisifik kost boraiks company ki rifaainari (tel shodhak kaarkhaana), jo alameda, California mein sthit hai.

nirmaan mein prayog

renaforsd kaankreet ka vyavahaar

padaarth

vishisht lakshan

jang-pratirodhi upaaya

ispaat renforsd kaankreet ke praay: asafalata kaarak

yaantrik

kaarbaneekaran

Rebar for foundations and walls of sewage pump station.

]</ref> The carbon dioxide from the air reacts with the alkali in the cement and makes the pore water more acidic, thus lowering the pH. Carbon dioxide will start to carbonate the cement in the concrete from the moment the object is made. This carbonatation process (in Britain, called carbonation) will start at the surface, then slowly move deeper and deeper into the concrete. If the object is cracked, the carbon dioxide of the air will be better able to penetrate into the concrete. When designing a concrete structure, it is normal to state the concrete cover for the rebar (the depth within the object that the rebar will be). The minimum concrete cover is normally regulated by design or building codes. If the reinforcement is too close to the surface, early failure due to corrosion may occur.

One method of testing a structure for carbonatation is to drill a fresh hole in the surface and then treat the surface with phenolphthalein. This will turn [pink] when in contact with alkaline cement, making it possible to see the depth of carbonatation. An existing hole is no good because the exposed surface will already be carbonated --->

kloraaid

chitr:October 2006 021.jpg
The Paulins Kill Viaduct, Hainesburg, New Jersey, is 115 feet (35 m) tall and 1,100 feet (335 m) long, and was heralded as the largest reinforced concrete structure in the world when it was completed in 1910 as part of the Lackawanna Cut-Off rail line project. The Lackawanna Railroad was a pioneer in the use of reinforced concrete

elkali –silika pratikriya

]</ref>[1] This phenomenon has been popularly referred to as "concrete cancer". --->

uchch elyumina cement ka antaran

salfet

faaibar-renforsd kaankreet

gair-ispaati renforsmeint

sandarbh