Ifom ye-corrugated culvert pipe ephambili kunye neemeko ezifanelekileyo (1) I-circular: imo yesiqhelo ye-cross-section, isetyenziswa kakuhle kuzo zonke iintlobo zeemeko zokusebenza, ingakumbi xa ubunzulu bokungcwaba bukhulu. (2) I-ellipse ethe nkqo: i-culvert, umbhobho wamanzi emvula, umjelo wokuhambisa amanzi amdaka, i-chan...
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