Journal of Waterway, Port, Coastal, and Ocean Engineering

Proper exploitation of information technology and the strengthening of the construction of waterway information are important ways to improve shipping efficiency and security. Considering the upstream reaches of the Yangtze River from Jiangjin to Chongqing (China) as a case study, a three-dimensional (3D) digital waterway system has been developed. The system, which comprises a server and a client, was designed to provide navigational and early warning services to shipping. In this paper, both the system architecture and the key methods of each module are presented. The functions and mutual relationships of the data input, database, 3D visualization, flow simulation, and early warning modules are described, and the key methods of the 3D digital waterway modeling, real-time simulation of waterway flow, and early warnings in navigation are discussed. The advantages of this system mainly concern the following aspects. (1) The 3D digital waterway model was established and integrated with virtual navigational elements, such as beacons, the water depth–contour surface, and navigable area, to enhance the intuitiveness of the digital waterway system and the comprehensiveness of its information. (2) Based on real-time hydrological data and a 2D hydrodynamic model, the waterway flow conditions with present-day inflow were simulated. The water depth distribution of a traditional inland electronic navigational chart (IENC) was provided, together with information on flow velocity and distribution, to improve the resolution and timeliness of the information acquisition. (3) According to Chinese inland navigational standards and the simulation of waterway flow conditions, the navigable area for shipping was zoned dynamically. In combination with the Global Positioning System (GPS) and networked ship-monitoring technologies, this system can provide early warnings for the safe navigation of shipping.

Many coastal areas have experienced extensive destruction as a result of tsunami waves. The coastal communities in Tohoku, Japan experienced the terrifying effect of giant tsunami waves in March 2011. Tsunami waves triggered by the 2011 Tohoku earthquake swept over existing seawalls and proceeded inland, damaging coastal structures and windbreak forestry. This devastating event demonstrated the need for strong countermeasures in coastal areas to mitigate the impact of huge tsunamis. This paper describes an experimental and numerical study of the tsunami-mitigation capabilities of canals oriented perpendicular to the tsunami motion. First, the use of a canal to reduce the effect of tsunami waves was investigated. Canals can help delay the tsunami arrival time and reduce the tsunami wave velocity and energy; however, the inundation depth may not be sufficiently affected if only canals are used as a countermeasure. An experimental study was then conducted to verify numerical simulations using the improved moving particle semi-implicit (MPS) method, and the experimental and numerical simulation results demonstrated good qualitative and quantitative agreement. A second series of numerical simulations was performed considering combined countermeasures comprising a canal and a dune. Such combined countermeasures have the potential to reduce both the tsunami wave velocity and the inundation depth. Through experiments and numerical simulations, this study examined how canals, individually or coupled with a dune, can play an important role in the mitigation of tsunami disasters.

The design of an integrated coastal berths and entrance-channel system is a complex challenge, considering the stochastic environment and time-consuming calculation works. Therefore, the authors implement a decision support system (DSS) for designing integrated coastal berths and entrance-channel systems (ICBECS-DSS) by means of simulation and parallel computing. The ICBECS-DSS provides a three-dimensional (3D) integrated design environment with a broad set of fully integrated functions to evaluate the proposed design alternatives, and to identify an optimal design from a large number of alternatives. The key components of ICBECS-DSS are a process interaction–based simulation model for ship operation (PI-SMSO) and a Java parallel processing framework–based parallel computing program (JPPF-PCP). The PI-SMSO component simulates ships in and out of a one- or two-way traffic channel, or a one-way channel with a ships-passing anchorage along the channel (SPAC), and ships discharging/loading at berths. The JPPF-PCP component provides a parallel computing environment to reduce their processing time of running a large number of simulation experiments. Finally, the ICBECS-DSS is applied to a case study of a coal terminal, decides whether any expansion projects are needed, and proposes expansion strategies to improve its port performance. The results prove that the ICBECS-DSS performs well and is helpful for effectively designing berths and entrance channels together. Therefore, the ICBECS-DSS can be used for support in decision making in integrated berths and entrance-channel systems and provides a reference for government agencies involved with the design and operation of port systems.

This paper presents a simple physical model for the numerical simulation of the behavior of buckling-type marine fenders. The proposed model is characterized by four parameters and is derived starting from similarities between the unstable behavior of marine fenders and shallow arches. In this model, the large displacements solution expressing the relationship between the model displacements and reaction force is determined in a nondimensional form, and the model parameters are calibrated to minimize residuals between real and predicted normalized reaction force–deflection curves. By considering an in-series arrangement of two elementary physical models, the approach can be also used to simulate the behavior of parallel-motion fenders. The proposed model can be directly implemented in commercial computer programs for structural analysis to study interactions arising between buckling-type marine fenders and flexible berthing structures. In this paper, the model effectiveness in capturing the behavior of fenders and parallel motions systems is evaluated through comparisons of results, both in terms of reaction force and absorbed energy, with data of real devices, obtained from three different manufacturers. Results demonstrate the model efficiency and suitability for reproducing the behavior of a wide range of devices.

A three-dimensional (3D) hydrodynamic numerical model is proposed to predict ship resistance and sinkage of an inland vessel sailing in restricted waterways. The flow around the ship is simulated, and the hydrodynamic forces acting on the hull are calculated. A quasi-Newton method is applied to find the vertical equilibrium position and to update the ship position. The numerical results are validated against experimental data and compared with empirical models. The effects of ship sinkage and channel restriction on ship resistance are also investigated. Including ship sinkage into the calculations significantly increases the model accuracy. Additionally, the empirical models tested in this study are not able to accurately predict ship resistance for the most restricted configurations. Finally, it is shown that ship resistance is more sensitive to water depth than channel width restriction.