Analysis on navigation risk of ships in bridge areas based on flow characteristics
To assess the navigation risk of ships in the bridge areas,a three-dimensional flow field model con-sidering vessel motion characteristics was constructed to investigate the yaw characteristics and mechanical properties of vessels passing through bridges under the influence of water flow.The safe navigational condi-tions and assessment grading standards for bridges and vessels were studied.A vessel downstream navigational risk assessment model based on fuzzy logic was established.The results reveal that the critical safe distances between bridge piers are 40 and 60 m,and the specific grading standards vary with different water periods.The safe speed ranges for vessels during low water,medium water,and flood periods are determined as 1.6 to 2.5,2.0 to 2.5,and 1.6 to 2.0 m/s,respectively.Flood periods poses higher navigational risks than other periods,primarily due to collisions with bridges when navigational dimensions are restricted.Compared with traditional assessment models,the proposed model simplifies the evaluation index system and reduces the mod-el subjectivity using direct ship forces and motion performance to determine grading criteria for factors such as bridges,water flow,and ship speed.
万方数据
维普
