MINIMIZING BED SCOUR INDUCED BY SHIP BOW-THRUSTERS BY USING QUAY WALL FLOW DEFLECTOR
DOI:
https://doi.org/10.11113/mjce.v31.16115Keywords:
Quay wall, bow-thruster, bed scour, flow deflectorAbstract
Recently, the combination of larger bow-thrusters installed with vessels have created higher levels of bed scour action affecting the berthing structure and its overall stability. Therefore, the bed near a quay wall structure must have sufficient strength by placing a bed protection which may cause the cost of the project to rise. This research is carried out to investigate experimentally the effect of modifying the geometry of the quay wall surface on minimizing bed scour. This is done by inserting flow deflectors within the longitudinal direction of the wall surface in order to deflect/minimize the water jet affecting the bed near the quay wall. Experimental tests had been carried out for single and triple deflectors. The results showed that the use of flow deflectors achieved a reduction in bed eroded area in front of quay wall face by about 63%, and causes the start point of erosion to move far away from it; this may improve the stability of quay walls. Therefore, the importance of the present study is testing a new possible measure to improve the stability of quay walls by minimizing the scour in front of the wall and to decrease the cost of bottom protection.
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