Research Of Ship-bridge Collision Risk Probability On Mountain River

It is obvious that there are peculiar navigation conditions with many bent waterways and rapid flow in mountain rivers and the corresponding waterway conditions changes as the water level fluctuates. In this condition, it is very difficult for ships to drive, meanwhile, the number of bridge increase rapidly, caused different degrees of hinder course, makes ship-bridge collision increase. Therefore, it is necessary to research ship-bridge collision risk on mountain river, and adopt active anti-collision measures according to forecasting results to reduce the accident of ship-bridge collision. In the premise of collecting a large number of data about mountain rivers, author conducte a series of calculation,and the ship-bridge collision risk were studied using method.And introduce three distribution factor: relative scale distribution factorμ1,sailing direction distribution factorμ₂,Corner corner distribution factorμ3,get conclusion as follows:(1) Formula of relative scale distribution factorμ₁ is:μ₁=B/L,B is the width of ship;L is the span of navigable hole; under the same size of ship,The ship-bridge collision risk of fleet is greater than single ship; under the same ship wide, the length and draft of ship havelittle influence on ship-bridge collision risk; formula established in case of values greater than 0.002, when less than 0.0025 ,the value has no influence in ship-bridge collision risk.(2) Formula of sailing direction distribution factorμ₂is:μ₂= (3n_下+n_上)/n_上+n_下; n_上 is the year navigable quantity of uplink ship, n_下 is the year navigable quantity of downside ship.(3) Formula of corner corner distribution factorμ₃is:μ₃ =0 .1281α+1.5376 This paper not only proposed an important reference to ship-bridge collision risk by AASHTO model on mountainous river, but also reduced the amount of engineering and project cost, proposed an important reference to ship-bridge collision risk and bridge protection.