Study On Collapse Probability Of Bridge By Shin Collision Based On AIS Data

As one of the important infrastructures in the modern transportation field,with the rapid development of marine transportation,bridges accrossing the port area and navigation channel become more frequent.At the same time,the number of ships increases quickly,and ships have development to maximization and fast velocity,the tonnage of ships has been increasing,and the speed of ships is also developing rapidly.Therefore,the probability of ship-bridge collision is greatly increased,and the collapse probability of bridges by ships collision is also increased.So,it is very necessary to study the collapse probability of bridge by ship collision to provide a basis for the bridge safety assessment process and reduce the loss of ship-bridge collision.Therefore,this paper will use the AIS data to analyze the navigation dynamics of ships near the Tongling Yangtze River Highway Bridge,and calculate the probability of ship-bridge collision by combining the probability model in the AASHTO specification,then use the analytical method and ship navigation data to fit the ship collision force estimation formula,finally,the collapse probability of bridge by ship collision is calculated according to the AASHTO specification.The main contents are as follows:First,the ships’ AIS data nearby Tongling Yangtze River Highway Bridge from 2016 to 2017 is collected,and the traffic flow of ships near the bridge is analyzed.The distribution of velocity,tonnage,the ships’ main scale,and yaw angles is obtained.These statistical analyses of AIS data are used to provide practical data support for subsequent research.Second,the different probability models of ship-bridge collision are compared and analyzed,and the AASHTO model is selected to calculate the probability of shi-bridge collision of the Tongling Yangtze River Highway Bridge.Then,the geometrical probability in the AASHTO model is determined by the actual lateral distribution of ships,and the parameters’ estimation method of lateral distribution of ships is corrected by the actual navigation data of ships.Considering the influence of the annual change of water,the water flow change factor is added to the calculation of yaw probability of ships in AASHTO model,thereby,correcting the yaw probability calculation formula in AASHTO.Then,using the simplify analytical formula of bow crushing force and the external dynamics of ship-bridge collision,combined with the navigation data of ships in the bridge area,a formula for quickly estimating the collision force is obtained.And the fitting formula is compared with other empirical formula.The accuracy of the formula is verified by simulation calculation.Finaly,the distribution of ships’ collision force is obtained by the fitting formula and AIS data.After that,compared with the collision resistance of bridge,combined with the probability of ship-bridge collision,the collapse probability of bridge by ship collision in a year is calculated.At the same time,the influence of anti-collision measures on the collapse probability is considered.Through the research of this paper,the actual ship traffic flow of Tongling Yangtze River Highway Bridge is understood,which can provide some reference for the local management department.Also,the more realistically correction of the probability model in AASHTO specification is conducted.Then,a estimation method of ship collision force based on the actual navigation data is obtained.Finally,the method for calculating the collapse probability of bridge based on the navigation data is obtained,which can provide a risk evaluation method suitable for ships’ navigation state in local area in the initial stage of bridge design.