Tus qauv tsim qauv ntawm cov bigid-yoog raws pawg thawj coj noj mov tshwj xeeb suav nrog cov hauv qab no:
1. Untad-bearing faib cov txheej txheem, cov khoom siv nruj ua ke ntawm cov khoom siv thauj khoom ntawm tag nrho cov kab ke ntawm cov txheej txheem tag nrho {}}
{2. bending deformation txoj cai: thaum lub nra muaj zog, tom qab siv hluav taws xob tsis haum,
{{03. Cov kab ke yooj yim ntawm cov kab ke ntawm cov kab ke sib xyaw thiab cov xeeb ntxwv muaj peev xwm zoo dua qub}
