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Summary Ship collisions threaten the safety of bridges over navigable waterways in modern times. Postcollision damage and condition assessment is thus of significant importance for decision making on whether closure of bridge to traffic is necessary and for planning the consequent bridge strengthening or retrofitting. Online structural health monitoring systems provide a unique approach to monitor bridge responses during ship collisions and detect the structural damage. The damage information contained in the monitoring data, which is critical for damage detection, however, is largely dependent on the sensor layout. In this paper, an optimal sensor placement method targeting postcollision damage detection of bridges is proposed for selecting the optimal sensor set so that the measured data are most informative for damage detection. The sensor configuration is optimized by a multi‐objective optimization algorithm, which simultaneously minimizes the information entropy index for each possible ship‐bridge collision scenario. One advantage of the proposed method is that it can handle the uncertainty of ship collision position. It also guarantees a redundancy of sensors for the most informative regions and leaves a certain freedom to determine the critical elements for monitoring. The proposed method is applicable in practice to determine the sensor placement, prior to field testing, with the intention of identifying postcollision damage. The cable‐stayed Ting Kau bridge in Hong Kong is employed to demonstrate the feasibility and effectiveness of the proposed method.

Ship-bridge collisions happen from time to time globally, and the consequences are often catastrophic. Therefore, this paper proposes a new high-pressure water jet interference (HPWJI) method for bridge pier protection against vessel collision. Unlike traditional methods that absorb energy by anti-collision devices to mitigate the impact force of ships on bridges, this method mainly changes the direction of ship movement by lateral high-pressure water jet impact, so that the ship deviates from the bridge piers and avoids collision. This paper takes China’s Shawan River as the background and simulates the navigation of a ship (weighing about 2000 t) in the HPWJI method in the ANSYS-FLUENT software. The simulation results show that the HPWJI method has a significant impact on the direction of the ship’s movement, enabling the ship to deviate from the pier, which is theoretically feasible for preventing bridge-ship collisions. The faster the ship’s speed, the smaller the lateral displacement and deflection angle of the ship during a certain displacement. When the ship speed is less than 7 m/s, the impact of water flow on the ship’s trajectory is more significant. Finally, this paper constructs a model formula for the relationship between the lateral displacement and speed, and surge displacement of the selected ship. This formula can be used to predict the minimum safe distance of the ship at different speeds.

Ship-bridge collision accidents often jeopardize the bridge structure, shorten the service lifespan, decrease the safety and durability of the bridge and cause losses in the seismic capacity. Therefore, it is necessary to conduct research and simulation on anti-collision facilities for piers. Aluminum foam has significant advantages in anti-collision and energy absorption performance as a new type of foam material. This paper uses ANSYS/LS-DYNA to simulate the process of a ship-bridge collision and analyzes the energy absorption effects of the steel-aluminum anti-collision sandwich structure.

In this paper, with the frequent occurrence of ship–bridge collision accidents as the context and the collision accident of the Lixinsha Bridge in China as the background, the scenario of a ship impacting a pier was simulated using ANSYS-FLUENT software, and the practical application possibility of the high-pressure water jet interference (HPWJI) anti-collision method was thoroughly investigated. Through the simulation analysis, the effectiveness of a high-pressure water jet with a total flow rate of 45 m3/s in altering the navigation direction of large-tonnage (2000 t) ships and avoiding obstacles was verified. Additionally, its impact on the stress of the ship steel plates and navigation status was also explored. It was found that, with reasonable layout and parameter adjustment, the high-pressure water jet technology could effectively intervene in the ship’s navigation trajectory while ensuring the structural safety of the ship, with minimal impact on the ship’s navigation stability and passenger comfort. Furthermore, the injection angle of the high-pressure water jet had a significant impact on the deflection and deceleration of the ship. Specifically, when the water jet impacted the ship along its forward direction, it could effectively increase the ship’s deceleration and deflection time, reducing the speed from 2.55 m/s to 1.7 m/s, a decrease of approximately 33%, significantly enhancing collision prevention effectiveness. This research provides important guidance for the practical application of high-pressure water jet collision prevention technology and is of great significance for improving the safety of waterway transportation.

In this research study, the characteristics of ship–bridge collision force formulas, in Chinese standards as well as international standards, were analyzed. By considering the damage situations of bridge piers under the cumulative ship collision conditions, a method of combining theoretical deduction with numerical analysis was adopted in this study. The goals of this study were to analyze and examine the sizes of the ship–bridge collision forces, along with the damage situations of piers, in order to propose a collision force calculation formula which took cumulative pier damages into consideration. Also, experimental verifications and an applicability analysis of the proposed formula were performed.

Ship-bridge collisions are one of the most common types of accidents, and bridge anti-ship collision devices are of great importance for bridge protection. First, a new type of assembled ultra-high performance concrete (UHPC) collision avoidance is proposed in this paper. The main components of the device are double-deck, two-way, densely reinforced ultra-high performance concrete floating boxes that are connected by high-strength bolts to form the whole structure and are equipped with steel supporting elements to form a collision energy dissipation device. The device is self-floating in water, is strongly energy absorbing due to plastic deformation, has a high degree of toughness, is corrosion resistant, and so on. This device also benefits from modular manufacturing, efficient installation, and easy replacement of damaged parts. Then, in this paper, the main parameters of the new collision avoidance, such as the material of the internal supporting elements, the wall thickness of the floating box, and the reinforcement ratio of the floating box, are optimized. Finally, a performance analysis and evaluation of the UHPC collision avoidance for the Honghe Bridge in Zhuhai City are carried out by using LS-DYNA program. The numerical results show that the new collision avoidance has significant advantages in reducing the ship–bridge collision force, prolonging the ship–bridge collision time, and protecting the ship. The results show that the assembled UHPC collision avoidance system is very effective for protecting ships and bridges in the event of a ship–bridge collision.

The ship safety domain plays a significant role in collision risk assessment. However, few studies take the practical considerations of implementing this method in the vicinity of bridge-waters into account. Therefore, historical automatic identification system data is utilised to construct and analyse ship domains considering ship–ship and ship–bridge collisions. A method for determining the closest boundary is proposed, and the boundary of the ship domain is fitted by the least squares method. The ship domains near bridge-waters are constructed as ellipse models, the characteristics of which are discussed. Novel fuzzy quaternion ship domain models are established respectively for inland ships and bridge piers, which would assist in the construction of a risk quantification model and the calculation of a grid ship collision index. A case study is carried out on the multi-bridge waterway of the Yangtze River in Wuhan, China. The results show that the size of the ship domain is highly correlated with the ship's speed and length, and analysis of collision risk can reflect the real situation near bridge-waters, which is helpful to demonstrate the application of the ship domain in quantifying the collision risk and to characterise the collision risk distribution near bridge-waters.

Ship collision accidents happen occasionally, many of which are caused by ship out of control. At present, there are few studies on the probability of collision of ships with bridges out of control at home and abroad, and no mature results have been formed in all aspects of the research on the accident of collision of ships with bridges, which need further study. In this paper, the influence of wind and flow is analyzed, the drift model of wind and flow is established, and the probability of collision of out of control ships with bridges is calculated, so as to provide technical support for safe navigation of ships and anti-collision design of piers

As design lifetimes being extended much longer than in the past, the importance of extreme events needs to be addressed. This paper presents a probabilistic design framework for evaluating very rare human-made hazards such as collisions and explosions. The proposed design against artificial hazards involves the development of an integrated design framework that is intended to simultaneously deal with the occurrence of an accidental event and the resulting resultant structural load using probabilistic scenariobased simulation. The proposed procedure consists of three steps. In the first step, event scenarios are identified and the probability of each occurrence is determined. The second step involves the construction of the conditional Complementary Cumulative Distribution Function (CCDF) of the load on those events. Finally, using the total probability theorem, the CCDF of the load during a period encompasses by an accidental events is calculated, and the design load is determined by a specified criterion which is described as the exceedance probability or the recurrence period of an event. As a specific example of the proposed general framework, detailed procedures for determining the design load in the case of a ship-bridge collision design, with an application to a cable-stayed bridge, are presented. Analysis results show that the proposed method effectively provides reasonable design loads, considering the many uncertainties inherent in the nature of a vessel collision hazard.

The risk of ship–bridge collisions should be evaluated using advanced models to consider different anti-collision and bridge-protection measures. This study aimed to propose a method to evaluate the effectiveness of active and passive safety measures in preventing ship–bridge collision. A novel ship–bridge collision probability formulation taking into consideration different safety measures was proposed. The model was applied at Jintang Bridge in China where the surrounding vessel traffic is ultra-crowded. We calculated the collision probability between the bridge and passing traffic using automatic identification system (AIS) data, Monte Carlo simulation, and Bayesian networks. Results under four different safety measures (i.e., active measures, passive measures, both measures and none) were analyzed and compared. The analysis concluded that both active and passive safety measures are effective in reducing the ship–bridge collision probability. Active measures, if deployed properly, can provide protection at an equivalent level than passive measures against collision risks. However, passive measures, such as setting arresting cables, are necessary in cases where the response time of the active measures is long. The proposed method and the results obtained from the case study may be useful for robust and systematic effectiveness evaluation of safety measures in other cases worldwide.