EXPERIMENTAL STUDIES ON BED FORM CHANGES ALONG MEANDER CHANNEL BANKS

We experimentally studied the location and depth of channel bed scouring along meander channel banks in thirty four different types of meander channels with various sets of wavelength and bend angle. The results are as follows:(1) The location of bed scours along side banks moves downstream gradually in whole reaches of weakly meander channels with the migration of alternate bars.(2) The location and shape of scours are stabilized along downstream banks of convex curves in meander channels with larger bend angles than critical ones.(3) Above critical angles scouring becomes deeper as bend angles become larger.(4) The depth of stabilized scours in short wavelength meander channels is large because their critical bend angles are larger than those in long wavelength meander channels.(5) When the location and shape of scours are stabilized, scouring depths are minimum in meander channels with slightly larger bend angles than critical ones.(6) As larger quantities of water are discharged, scouring depth becomes small in smaller-angled channels but it becomes large in larger-angled ones.