IbKuv-beamyog ib qho ntawm ntau tus tswv cuab nrog I lossis H-shaped cross-section. Cov ntsiab lus technical rau cov khoom zoo sib xws suav nrogH-beam(rauuniversal kab, UC), w-beam(rau "wide flange"),universal beam (UB), dov steel joist (RSJ), los yogob-T(tshwj xeeb hauv Polish, Bulgarian, Spanish, Italian thiab German). I-beams feem ntau yog ua los ntawm cov qauv hlau thiab ua haujlwm rau ntau yam kev siv.
Cov ntsiab lus kab rov tav ntawm qhov kuv yog hu ua flanges, thiab lub caij ntsug yog hu ua "web". Lub vev xaib tiv thaiv shear quab yuam, thaum lub flanges tiv thaiv feem ntau ntawm lub sijhawm khoov tau ntsib los ntawm cov nqaj. Euler-Bernoulli beam kab zauv qhia tau hais tias qhov seem I-puab yog ib daim ntawv zoo heev rau nqa ob qho tib si dabtsi yog khoov thiab shear loads nyob rau hauv lub dav hlau ntawm lub web. Ntawm qhov tod tes, tus ntoo khaub lig-section muaj lub peev xwm txo qis hauv txoj kev hloov pauv, thiab tseem tsis muaj txiaj ntsig hauv kev nqa torsion, uas feem ntau hollow structural seem yog nyiam.
Xyoo 1849, txoj kev tsim cov I-nqaj, raws li dov los ntawm ib qho ntawm cov hlau wrought,[1]tau patented los ntawm Alphonse Halbou ntawm Forges de la Providence hauv Marchienne-au-Pont, Belgium.[2]
Bethlehem Steel, headquartered nyob rau hauv Bethlehem, Pennsylvania, yog ib tug ua lag luam ntawm dov structural steel ntawm ntau yam ntoo khaub lig-sections nyob rau hauv American choj thiab skyscraper ua hauj lwm nyob rau hauv nruab nrab -20th caug xyoo.[3]Rolled cross-sections tam sim no tau raug tshem tawm ib nrab nyob rau hauv xws li kev ua hauj lwm los ntawm fabricated cross-sections.
