Cov lus piav qhia H-beam yog ib qho kev lag luam thiab kev ua haujlwm siab nrog ntau qhov kev faib tawm ntawm cheeb tsam sib luag thiab tsim nyog lub zog-rau-qhov hnyav.Nws yog lub npe vim hais tias nws tus ntoo khaub lig yog tib yam li tsab ntawv Askiv "H".Txij li txhua qhov chaw ntawm H-nqaj yog teem rau ntawm lub kaum sab xis, H-beam muaj qhov zoo ntawm kev muaj zog dabtsi yog khoov, kev tsim kho yooj yim, txuag nqi thiab lub teeb yuag hauv txhua qhov kev qhia, thiab tau siv dav.qhia lub...