Motivated by the operational scenarios of lock scheduling, we propose a serial-lock chain navigation problem (SLCNP) modeled on the Three Gorges-Gezhouba Dam (TGGD) for the first time. Ship grouping, synchronized moving, and grouped waiting operations are integrated into the ship navigation process. A mixed integer programming (MIP) model that incorporates real-world constraints such as ship priority, service fairness, traffic flow equilibrium, and phased ship placement is presented to optimize ship throughput and ship stay time. To solve the SLCNP, a sort-pick strategy-based swarm intelligence algorithm (SPSSIA) framework is developed that integrates the characteristics of SLCNP through a hybrid multi-section encoding method and a two-stage heuristic decoding approach. A swarm intelligence evolution mechanism is used to improve the search ability and robustness of the framework. Several instances are generated based on real data to verify the correctness and effectiveness of the model and algorithm. Computational results demonstrate the applicability and effectiveness of the proposed SPSSIA. Further analysis of the experimental results indicates that the key impact factors significantly influence the navigational performance of the TGGD system. The results of this study will provide practical guidance for the operational processes of inland river hubs with comparable characteristics.

Wire rope will have defects such as local faults (LF) and loss of metal area (LMA) during the long-term using process. The nondestructive testing method of magnetic flux leakage (MFL) has been widely used in wire rope defect detection. Currently, the detecting distance between magnetic sensors and wire rope with the MFL method is relatively small (2–5 mm). Considering the inner surface of the sensor head is close to the wire rope, it quickly leads to the sensor head scraping off the surface oil of the wire rope or being stuck by a cut wire in the course of MFL detection. Therefore, it is challenging to realize the sensor with MFL detection of wire rope obtaining the weak signal at a large lift-off (>30 mm). This study used finite element analysis to verify if the MFL signal exists at the large lift-off (>30 mm). Meanwhile, the sensor head was improved using an open magnetizer to make the wire rope reach saturation and excite enough magnetic leakage field. By combining magnetic sensing and coupling and a weak analog signal processing method, not only was the signal effectively detected, but also the signal-to-noise ratio (SNR) was improved. Finally, experiments verify the feasibility of detecting defects at a large distance. The method also has been applied in the high-speed detection of wire rope, which can detect broken wire of 1 mm diameter.

Based on the introduction and analysis of difficulties encountered during technical inspection of the wire rope of a winding mine hoist (WMH) working at high speed, an open-loop permanent magnet magnetizer was used to simulate and analyze the effect of the structural dimensions of this magnetizer on the magnetic leakage field of a defect, and the results of the simulation analysis were initially verified by experiments. Additionally, in order to keep the axial position of the probe in line with the axial position of the wire rope, a rocker arm was proposed to act in coordination with a motor to drive the clutching open and closed probe, thereby creating an on-line nondestructive testing device to float and track the movement of the wire rope in different directions. Finally, the device was applied to testing of WMH wire rope on site to validate the effectiveness and feasibility of the method.

As an essential part of the water conservancy hub, the miter gate undertakes the vital task of navigational operation and works in a complex basin with a high water level drop for a long time; therefore, it is necessary to ensure its safe operation. In this paper, taking the Gezhouba No. 2 ship lock miter gate as an example, the actual gate stress and crack signals are obtained using the online monitoring system. The stress distributions of the gate under different working conditions are studied using finite element simulation analysis. Combining simulation analysis with the collected signal analysis, the operation status of the actual gate under each working condition is evaluated. The results show that the stress analysis of the online monitoring is consistent with the finite element analysis results, which verifies the reasonableness of the sensor arrangement. The stress is more concentrated in the area of the gate shaft column, the middle door seam, and the rear flange plate during the operation of the miter gate, and the maximum stress appears on the central sector shaft column of the gate. The cracks of the miter gate mainly appeared in the lower layer of the gate body, and the cracks expand gradually during the long-term operation of the gate. The crack expansion speed corresponds to the miter gate’s stress magnitude.

As an important part of the navigation facilities for water conservancy and electricity in Gezhouba, the operation safety of herringbone gates is critical. Due to the minor torsional stiffness of the gate, it is easy to produce torsional deformation during operating under the water pressure, wind load, and gravity, which may lead to fatigue damage. In this study, a gate model with a combination of plate unit and the solid unit was developed, taking a ship lock herringbone gate as an example. According to the gate load under different working conditions, such as self-weight, surge, etc., in this research, we used the finite element analysis software ANSYS to analyze and calculate the stress and strain of the gate, with and without a back tie, and obtained the characteristics of the gate torsional deformation under various working conditions. The results show that the gate’s deformation degree and the direction under different working conditions vary greatly. The maximum deformation point mostly appears in the upper or lower corners of the oblique joint column. The gate deformation can be significantly reduced by adding the back tie. The research results provide a theoretical basis for further optimizing the design of the gate and installation of the back tie to reduce the fatigue damage of the miter gate.