Effect of ship-lock-induced surges on navigation safety in a branched lower approach channel system

Abstract

Ships docking and traveling in a branched lower approach channel system are at risk from surges caused by multi-lane locks during emptying operations. For this reason, water-level variations in the lower approach channel in response to discharge, interval running time, and outlet location of lock operations were studied using a 2-D hydrodynamic model validated by physical model tests, and the impact of water level variation on navigation safety under extreme operation scenarios of a quadruple-lane lock group was identified. Results indicated that discharge and interval running time of lock emptying had the greatest impact on the water level variation at the lock head. Water level variation at the lower lock head of the ship lift exhibited a trend of first decreasing and then increasing with the increment of the discharge from the lock chamber into the outer river. Specifically, the surge height at the lock head of the ship lift reached the minimum when approximately 40% of the discharge generated by dual-lane locks during emptying operations was released into the outer river. Overall, the simultaneous operation of quadruple-lane lock group and unit load rejection should be avoided in engineering applications.

An Index Model for the Evaluation of the Performance of Lock Navigation Scheduling Rules Considering the Perspective of Stakeholders

“…When the lock area is congested, vessel collision accidents are prone to cause a chain reaction. The safety of the lock navigation must be taken into full consideration [37].…”

“…In order to assess the performance of lock navigation scheduling rules, this study uses a Bayesian network model to analyze the influencing factors. Then, the improved composite index method [37][38][39][40] is used to downscale the evaluation of different stakeholders on the performance of scheduling rules, combine the conditional probability of factors in the Bayesian network for the measurement of the performance value, and con-…”

“…In order to assess the performance of lock navigation scheduling rules, this study uses a Bayesian network model to analyze the influencing factors. Then, the improved composite index method [37][38][39][40] is used to downscale the evaluation of different stakeholders on the performance of scheduling rules, combine the conditional probability of factors in the Bayesian network for the measurement of the performance value, and construct an index-type evaluation model of the performance of lock navigation scheduling rules by the relationship between the base period of the lock navigation scheduling system and the performance value in the observation period. Meanwhile, the index contains an overall index and criterion node index, which can reflect the comprehensive operation performance of the model as well as describe the operation performance of the model under the criterion of efficiency, fairness, and safety.…”

Effect of Parameters of Ditch Geometry on the Uniformity of Water Filling in Ship Lock Chambers

“…Ship locks are one of the important forms of navigational architecture to overcome upstream and downstream water level differences in rivers. In addition, the construction of ship locks can often reflect the capacity for inland navigation, addressing the increasing demand for waterway transportation in China in recent decades [4,5]. A ship lock not only needs to be able to fill with water and empty out quickly within a specified time, but also needs to ensure the safety of the mooring ship and the lock itself [6].…”

Study of Navigable Flow Conditions in the Intermediate Channel of Decentralized Cascade Locks

“…Unsteady flow fluctuations were reflected and superimposed in propagation to form a complex flow state, thus causing the vessel's transverse rocking, longitudinal tilt, and droop effect, affecting vessel navigation safety [9]. It was crucial to limit the fluctuations caused by the filling and emptying of locks to ensure the vessel's safety, where the water surface slope and flow velocity are the important parameters to measure whether the vessel can navigate safely [10].…”