Marine Structures最新文献_第10页

Numerical study of wave forces on truncated cylinder arrays generated by focused waves 聚焦波对截短圆柱阵列波浪力的数值研究

IF 5.1 2区工程技术 Q1 ENGINEERING, CIVIL

Marine Structures

Pub Date : 2026-01-15 Epub Date: 2025-08-05 DOI: 10.1016/j.marstruc.2025.103907

Qinghe Fang , Hui Wang , Hanchen Zhang , Chunhui Liu , Yongfu Wu , Zaixian Chen , Anxin Guo

Vertical cylinders are commonly used as foundation supports in offshore engineering. Wave forces on a single cylinder have been widely studied and developed into methods for calculating wave loads. However, wave forces on truncated cylinder arrays, representing floating foundations, have been rarely investigated. In this study, the wave forces on truncated cylinder arrays in 2 × 2 and 4 × 4 configurations generated by focused waves were numerically studied. The numerical model was established with the volume of fluid (VOF) method and the k-ω SST turbulence model based on OpenFOAM. The model accuracy was validated against experimental data from literature. The array effect was discussed by comparing the characteristics of wave forces on truncated cylinders at different positions. It was found that there is a nonlinear relationship between wave forces on cylinder arrays and wave amplitude. The wave force distributions of cylinder arrays show strong symmetry relative to wave incidence, with minimal amplitude variations across columns, while enlarged arrays amplify phase modulation. Surrounding cylinders provide significant sheltering effects to inner cylinders. Besides, the spectra of wave force on truncated cylinders were modulated by the spectral characteristics of incident focused waves. An empirical prediction method based on peak wave frequency was proposed to estimate dimensionless wave forces and their spatial distribution within cylinder arrays. This study enhances the understanding of wave force distributions on cylinder arrays under extreme wave and provides valuable insights into structural design of offshore structures.

垂直圆柱体是海洋工程中常用的基础支撑形式。波浪力在单个圆柱体上的作用得到了广泛的研究，并发展成为计算波浪荷载的方法。然而，对代表浮动基础的截短圆柱阵列的波浪力很少进行研究。本文研究了聚焦波对2 × 2和4 × 4两种构型截短圆柱阵列产生的波浪力。采用流体体积法（VOF）和基于OpenFOAM的k-ω SST湍流模型建立了数值模型。通过文献中的实验数据验证了模型的准确性。通过比较不同位置截圆柱上波浪力的特性，讨论了阵列效应。结果表明，圆柱阵列波浪力与波浪幅值之间存在非线性关系。圆柱阵列的波力分布相对于入射波表现出很强的对称性，柱间振幅变化最小，而放大后的阵列放大了相位调制。外筒对内筒具有显著的遮蔽作用。此外，截断柱体上的波浪力谱受到入射聚焦波谱特征的调制。提出了一种基于波浪峰值频率的经验预测方法，用于估计柱体阵列内无量纲波浪力及其空间分布。该研究增强了对极端波浪作用下圆柱阵列波浪力分布的认识，为海上结构设计提供了有价值的见解。

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引用次数: 0

Theoretical study of rectangular foam core sandwich plate under low velocity ice wedge impact 低速冰楔冲击下矩形泡沫芯夹芯板的理论研究

IF 5.1 2区工程技术 Q1 ENGINEERING, CIVIL

Marine Structures

Pub Date : 2026-01-15 Epub Date: 2025-08-06 DOI: 10.1016/j.marstruc.2025.103920

Wen Xiao , Yong Hu , Yinggang Li

In this study, a theoretical model is developed to investigate the impact response of rectangular foam-core sandwich plates subjected to low velocity ice wedge impacts. By employing the pressure-area (P-A) relationship of ice wedge and the yield criterion for foam-core sandwich cross-sections, the ice fragmentation energy dissipation and structural plastic deformation energy dissipation are respectively solved. Based on the shared-energy dissipation mechanism and iterative solution of ice impact response, the plastic deformation and energy dissipation characteristics of rectangular foam core sandwich plates under low velocity ice wedge impact are derived. The analytical predictions are compared with the numerical and experimental results to verify the accuracy of theoretical model. Besides, the effects of impact positions and ice wedge thickness as well as aspect ratio on dynamic response of rectangular foam core sandwich plate under low velocity ice wedge impact are studied. Results demonstrate that the analytical predictions for plastic deformation and ice fragmentation energy agree well with numerical and experimental results. This work provides an important guidance for the structural design and safety analysis of rectangular foam core sandwich plate under ice impact.

本文建立了矩形泡沫芯夹层板在低速冰楔冲击下的冲击响应理论模型。利用冰楔的压力-面积（P-A）关系和泡沫芯夹层截面的屈服准则，分别求解了冰破碎耗能和结构塑性变形耗能。基于冰冲击响应的共享能量耗散机制和迭代解，推导了矩形泡沫芯夹层板在冰楔低速冲击下的塑性变形和能量耗散特性。将解析预测结果与数值和实验结果进行了比较，验证了理论模型的准确性。此外，还研究了冲击位置、冰楔厚度以及长径比对低速冰楔冲击下矩形泡沫芯夹层板动力响应的影响。结果表明，塑性变形和破冰能的解析预测与数值和实验结果吻合较好。为矩形泡沫芯夹芯板在冰冲击下的结构设计和安全性分析提供了重要的指导。

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引用次数: 0

A probabilistic framework for assessing vessel impact on bridges considering technical failures: insights from the Baltimore accident case study 考虑技术故障评估船舶对桥梁影响的概率框架：来自巴尔的摩事故案例研究的见解

IF 5.1 2区工程技术 Q1 ENGINEERING, CIVIL

Marine Structures

Pub Date : 2026-01-15 Epub Date: 2025-08-05 DOI: 10.1016/j.marstruc.2025.103906

Lucjan Gucma , Milan Batista , Marko Perkovič

This article presents new probabilistic approach to assessing the risk of collisions between ships and bridges, focusing specifically on the incident involving the container ship Dali and the collapse of the Francis Scott Key Bridge in Baltimore. Current risk models are significantly limited, particularly given the evolution of navigation practices and the adoption of ultra-precise positioning systems. The proposed method enhances predictive capability by incorporating three categories of technical ship failure: loss of power supply, failure of the main engine, and malfunction of the steering gear. A simulation-based reconstruction of the Dali incident was conducted using the NTPro 6000 full-mission bridge simulator. This reconstruction forms the basis for an in-depth analysis of four critical components: (1) the probable technical cause(s) of the accident; (2) key stakeholders and influencing factors in the risk profile of ship-to-bridge interactions; (3) engineering and procedural options for mitigating bridge strike incidents; and (4) expert assessment of feasible preventive measures, particularly those available to maritime pilots. The study includes the results of a targeted survey of maritime professionals, including pilots and captains. The survey aimed to evaluate the effectiveness of current preventive protocols and to identify potential gaps in training, coordination, and technical response in emergency situations. The findings provide valuable insights into the dynamics of maritime accidents in confined waters and propose a structured approach to enhancing risk assessment methodologies through the use of realistic failure scenarios and expert-informed analysis.

本文提出了一种新的评估船舶与桥梁碰撞风险的概率方法，特别关注涉及集装箱船达利和巴尔的摩弗朗西斯斯科特基桥倒塌的事件。目前的风险模型有很大的局限性，特别是考虑到导航实践的发展和超精确定位系统的采用。该方法将船舶技术故障分为电源中断、主机故障和舵机故障三大类，提高了预测能力。利用NTPro 6000全任务桥模拟器对大理事件进行了基于模拟的重建。这种重构构成了对四个关键部分进行深入分析的基础：(1)事故可能的技术原因；(2)船桥相互作用风险特征的关键利益相关者及其影响因素；(3)减轻桥梁罢工事件的工程和程序选择；(4)专家评估可行的预防措施，特别是可供海上引航员使用的措施。该研究包括对海事专业人员（包括飞行员和船长）的针对性调查结果。调查的目的是评价目前预防性协议的有效性，并查明在紧急情况下培训、协调和技术反应方面的潜在差距。研究结果为密闭水域的海上事故动态提供了有价值的见解，并提出了一种结构化的方法，通过使用现实故障场景和专家信息分析来增强风险评估方法。

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引用次数: 0

Digital twin-driven structure safety monitoring method for revolving floating cranes based on multi-fidelity surrogate models 基于多保真度代理模型的旋转式浮式起重机双驱动结构安全监测方法

IF 5.1 2区工程技术 Q1 ENGINEERING, CIVIL

Marine Structures

Pub Date : 2026-01-15 Epub Date: 2025-08-30 DOI: 10.1016/j.marstruc.2025.103925

Xiaobang Wang , Hao Wang , Shuo Wang , Jialin Jiang , Bing Liang , Zhijie Liu

The Revolving Floating Crane (RFC) plays a crucial role in offshore lifting operations, making its operational safety a top priority. However, large lifting loads and harsh conditions during manual operations can cause unstable postures or structural failures, potentially leading to serious economic losses and personal injuries. To address these safety concerns, comprehensive monitoring of RFC operations is essential. Thus, this study proposes a digital twin (DT)-driven structure safety monitoring method based on multi-fidelity surrogate model (MFSM). In the implementation, the structural and functional characteristics of actual RFCs are referenced to build an RFC physical entity. By identifying key operational safety indicators, a sensor-based data acquisition module for RFC entity is developed. Relying on the entity, finite element simulations and actual experiments are then conducted to generate multi-fidelity training data of RFC operational safety, which are used to establish corresponding MFSMs. By Unity3D engine, a virtual interaction platform for data fusion is created for safety monitoring, enabling real-time synchronization from the RFC physical entity to DT model. Finally, physical safety monitoring experiments are conducted on RFC lifting operations. Experiment results demonstrate that the proposed method delivers high real-time performance and accuracy, effectively meeting the engineering requirements for RFC lifting safety monitoring.

旋转浮式起重机（RFC）在海上起重作业中起着至关重要的作用，其运行安全性是重中之重。然而，在人工操作过程中，大的起重载荷和恶劣的条件下，可能导致姿势不稳定或结构失效，可能导致严重的经济损失和人身伤害。为了解决这些安全问题，对RFC操作进行全面监控至关重要。因此，本研究提出一种基于多保真度代理模型（MFSM）的数字孪生驱动结构安全监测方法。在实现过程中，参考实际RFC的结构和功能特点，构建RFC物理实体。在确定关键运行安全指标的基础上，开发了基于传感器的RFC实体数据采集模块。以实体为依托，进行有限元仿真和实际实验，生成RFC运行安全的多保真度训练数据，用于建立相应的mfsm。通过Unity3D引擎创建安全监测数据融合虚拟交互平台，实现RFC物理实体到DT模型的实时同步。最后，对RFC吊装作业进行了物理安全监测实验。实验结果表明，该方法具有较高的实时性和准确性，能有效满足RFC起重安全监控的工程要求。

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引用次数: 0

Mechanical characterization of bend-twist coupling behavior in composite marine hydro-kinetic turbine blades 船用复合水动力涡轮叶片弯扭耦合性能的力学表征

IF 5.1 2区工程技术 Q1 ENGINEERING, CIVIL

Marine Structures

Pub Date : 2026-01-15 Epub Date: 2025-08-20 DOI: 10.1016/j.marstruc.2025.103924

Miguel A. González-Montijo , Katherine Van Ness , Zack Tully , Richard Wiebe , Brian Polagye , Michael R. Motley

Bend-twist coupling is a phenomenon in some structures whereby bending moments produce not only transverse deflection, but also twist. Recent decades have seen a growing trend toward exploiting this mechanism to advance the performance of structures. This coupling effect can be caused by geometric factors such as eccentric loading, or it can be induced by leveraging the anisotropic nature of fiber-matrix composites. This study focuses on the purposeful use of unbalanced layups in laminated fiber-reinforced polymer spars to tailor bend-twist coupling behavior.

An especially promising application of bend-twist coupled composite structures is their potential use in marine energy turbines. Recent efforts have shown that bend-twist coupling can be used to reduce loading on turbine blades in overload conditions, thereby improving their robustness, without significantly reducing power generation under normal operating conditions. This work robustly characterizes, using both experimental and numerical methods, the relationship between the effective fiber angle (a design parameter) and the: (i) degree of bend-twist coupling, (ii) bending stiffness, and (iii) natural frequencies (system properties) of laminated composite blades. The outcomes of this work will help designers choose the optimal fiber angles for specific applications and will serve as a strong benchmark for the validation of computational models.

弯扭耦合是某些结构中的一种现象，其中弯矩不仅产生横向挠度，而且产生扭转。近几十年来，人们越来越倾向于利用这种机制来提高结构的性能。这种耦合效应可能是由偏心载荷等几何因素引起的，也可能是利用纤维基复合材料的各向异性引起的。本研究的重点是在层压纤维增强聚合物梁中有目的地使用不平衡层来定制弯曲-扭转耦合行为。弯扭耦合复合结构的一个特别有前途的应用是它们在海洋能源涡轮机中的潜在应用。最近的研究表明，弯扭耦合可以用来减少涡轮叶片在过载条件下的负荷，从而提高其稳健性，而不会显著减少正常工作条件下的发电量。这项工作通过实验和数值方法强有力地描述了有效纤维角（一个设计参数）与层压复合材料叶片的弯扭耦合程度、弯曲刚度和固有频率（系统特性）之间的关系。这项工作的结果将有助于设计人员为特定应用选择最佳的纤维角度，并将作为验证计算模型的有力基准。

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引用次数: 0

Study on plasma arc penetration process of abandoned offshore wells 海上废弃井等离子弧穿透过程研究

IF 4 2区工程技术 Q1 ENGINEERING, CIVIL

Marine Structures

Pub Date : 2025-10-15 Epub Date: 2025-07-03 DOI: 10.1016/j.marstruc.2025.103889

Peng Liu , Yonghong Liu , Qingxiang Wang , Xinlei Wu , Chi Ma

Recently, massive numbers of offshore production platforms have faced decommissioning. Abandoned offshore wells demolition is a significant part of offshore platform decommissioning. This work explored the plasma arc penetration process of abandoned offshore wells. Three types of workpieces were made for underwater penetration experiments. Workpiece 1 was a single-layer steel plate, workpiece 2 was a double-layer steel plate with a gap, and workpiece 3 was a double-layer steel plate with a cement layer. It was found that slag bridging occurred during the penetration of workpiece 2. Slag bridging was closely related to the gap size. There was no slag bridging during the penetration of workpiece 3, but its penetration difficulty was the greatest among the three working conditions. It was also found that the penetration effect of the second steel plate was strongly influenced by the branching arc acting on the second steel plate. The wider the gap and the cement layer, the lower the branching arc current on the second steel plate and the worse the penetration effect. In summary, the plasma arc can penetrate all three types of workpieces under certain operating conditions. This technology is expected to play a significant role in abandoned offshore wells demolition.

最近，大量海上生产平台面临退役。海上弃井拆除是海上平台退役的重要组成部分。本研究探讨了海上废弃井的等离子弧穿透过程。制作了三种类型的工件进行水下侵彻实验。工件1为单层钢板，工件2为带间隙的双层钢板，工件3为带水泥层的双层钢板。发现在工件2的侵彻过程中发生了渣桥接现象。渣桥效应与间隙大小密切相关。工件3在侵彻过程中没有出现焊渣桥接现象，但其侵彻难度在三种工况中最大。研究还发现，作用在第二钢板上的分支弧对第二钢板的侵彻效果有很大影响。间隙和水泥层越宽，第二钢板上的分支弧电流越低，穿透效果越差。综上所述，在一定的操作条件下，等离子弧可以穿透所有三类工件。这项技术有望在海上废弃油井的拆除中发挥重要作用。

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引用次数: 0

Analytical formulation for natural frequency of monopile-supported offshore wind turbine: Calibration and application 单桩支撑海上风力机固有频率解析公式：校准与应用

IF 4 2区工程技术 Q1 ENGINEERING, CIVIL

Marine Structures

Pub Date : 2025-10-15 Epub Date: 2025-07-23 DOI: 10.1016/j.marstruc.2025.103901

Fangyu Wu , Zhongxuan Yang , Subhamoy Bhattacharya , Rongqiao Xu , Sai Fu

The dynamic response of monopile supported offshore wind turbines (OWT) plays a critical role in their structural design optimization. During the design optimization process, various methods, including numerical simulations and closed-form solutions, are used to analyze the free vibration behavior of monopile-supported OWTs. This study introduces an analytical model based on the Rayleigh-Ritz method to derive a fast yet accurate estimation formula for natural frequencies.

Given the increasing deployment of OWTs in deeper waters with complex seabed conditions prone to scouring, as well as the trend toward larger turbine sizes, the calibrated model and Rayleigh-Ritz formula are applied to assess the effects of scouring on natural frequencies across different turbine scales. The study also examines the relationship between the natural frequencies computed using a fixed-base assumption and the effect of foundation flexibility, accounting for variations in ground conditions. Furthermore, the work explores frequency trends across multiple turbines scales and identifies feasible turbine sizes for deployment in four specific seas of China.

单桩支撑海上风力发电机组的动力响应对其结构优化设计具有重要意义。在优化设计过程中，采用数值模拟和闭式解等多种方法对单桩支承的自振特性进行了分析。本文引入基于瑞利-里兹法的解析模型，推导出快速准确的固有频率估计公式。考虑到owt越来越多地部署在更深的水域，且海底条件复杂，容易发生冲刷，以及涡轮机尺寸越来越大的趋势，应用校准模型和瑞利-里兹公式评估了不同涡轮机尺度上冲刷对固有频率的影响。该研究还考察了使用固定基础假设计算的固有频率与基础灵活性的影响之间的关系，考虑了地面条件的变化。此外，该工作还探讨了多个涡轮机规模的频率趋势，并确定了在中国四个特定海域部署的可行涡轮机尺寸。

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引用次数: 0

Fatigue damage prediction model for broadband non-Gaussian random processes based on Bayesian optimized random forest 基于贝叶斯优化随机森林的宽带非高斯随机过程疲劳损伤预测模型

IF 4 2区工程技术 Q1 ENGINEERING, CIVIL

Marine Structures

Pub Date : 2025-10-15 Epub Date: 2025-07-10 DOI: 10.1016/j.marstruc.2025.103894

Kuilin Yuan , Boyu Huang , Hanchu Qin

Marine structures operating in harsh ocean environments are continuously exposed to cyclic loads that may induce fatigue damage. Accurate fatigue damage prediction is therefore essential for ensuring the structural integrity of marine structures. When the structural responses exhibit broadband non-Gaussian characteristics, the existing frequency-domain methods appears to have insufficient accuracy. Although the time-domain rainflow counting method can achieve higher accuracy, it incurs high computational costs. To address these challenges, this study develops a fatigue damage prediction model for broadband non-Gaussian random processes by combining the random forest (RF) algorithm with Bayesian optimization (BO) approach. The BO-RF model is trained by employing the database including the fatigue damage related to diverse power spectra with a broad range of bandwidth parameters and a variety of S-N curve slope, skewness and kurtosis. Extensive numerical simulations demonstrate that the developed BO-RF model is superior to the tradition frequency-domain methods in terms of accuracy and robustness. Furthermore, comparative analysis against an artificial neural network (ANN) model further reveals the advantages of BO-RF model in both training efficiency and generalization capability. This study demonstrates the proposed BO-RF model can provide a feasible solution for accurate and efficient fatigue damage prediction of marine structures under broadband non-Gaussian random loading.

在恶劣的海洋环境中工作的海洋结构物不断地暴露在可能引起疲劳损伤的循环荷载下。因此，准确的疲劳损伤预测对于保证海洋结构的完整性至关重要。当结构响应表现出宽带非高斯特性时，现有的频域方法精度不足。时域雨流计数方法虽然精度较高，但计算成本较高。为了解决这些挑战，本研究将随机森林（RF）算法与贝叶斯优化（BO）方法相结合，开发了宽带非高斯随机过程的疲劳损伤预测模型。BO-RF模型的训练采用了包含多种功率谱、宽带宽参数和多种S-N曲线斜率、偏度和峰度的疲劳损伤数据库。大量的数值模拟表明，所建立的BO-RF模型在精度和鲁棒性方面都优于传统的频域方法。通过与人工神经网络（ANN）模型的对比分析，进一步揭示了BO-RF模型在训练效率和泛化能力方面的优势。研究表明，所提出的BO-RF模型能够为船舶结构在宽带非高斯随机载荷作用下的准确、高效的疲劳损伤预测提供一种可行的解决方案。

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引用次数: 0

Theoretical analysis of elastic collapse in metallurgical clad pipes under external pressure 外压作用下冶金包层管道弹性坍塌的理论分析

IF 4 2区工程技术 Q1 ENGINEERING, CIVIL

Marine Structures

Pub Date : 2025-10-15 Epub Date: 2025-06-20 DOI: 10.1016/j.marstruc.2025.103861

Mingjie Hu , Haohong Jian , Menglan Duan , Qiwei Wu , Weifeng Zheng

Metallurgical Clad Pipes (MCPs), due to their unique manufacturing process and excellent corrosion resistance, are key equipment for transporting highly corrosive oil and gas in offshore systems. However, the high external hydrostatic pressure in deep-sea environments poses significant risks of collapse, threatening the structural safety of MCPs. In this research, the elastic collapse performance of MCPs under external pressure is investigated by deriving a novel analytical formula based on Donnell shell theory and the Ritz method. The proposed formula considers the perpendicularity of pressure during deformation and is validated through comparisons with the DNV-ST-F101 formula and FEM simulations. The findings demonstrate that the elastic post buckling equilibrium path of MCPs follows the same pattern as that of conventional single-metal pipelines. Moreover, the proposed formula shows improved accuracy and greater applicability to various geometric properties and materials. Research works may provide a theoretical basis to improve the design and safety of MCPs and contribute to the ongoing development of offshore pipeline engineering.

冶金包层管（mcp）由于其独特的制造工艺和优异的耐腐蚀性，是海上系统中输送高腐蚀性油气的关键设备。然而，深海环境中较高的外部静水压力带来了巨大的坍塌风险，威胁着mcp的结构安全。本文基于Donnell壳理论和Ritz方法，推导了MCPs在外压作用下的弹性坍塌性能分析公式。该计算公式考虑了变形过程中压力的垂直性，并与DNV-ST-F101计算公式和有限元模拟结果进行了对比验证。结果表明，mcp管道的屈曲后弹性平衡路径与传统的单金属管道相同。此外，所提出的公式具有更高的精度和更大的适用性，适用于各种几何性质和材料。研究工作可以为改进mcp的设计和安全性提供理论依据，并有助于海洋管道工程的不断发展。

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引用次数: 0

Structural optimization of non-rotating floating cranes: Analysis of classical designs and development of a dual-pontoon configuration 非旋转浮式起重机结构优化：经典设计分析及双浮桥结构的发展

IF 4 2区工程技术 Q1 ENGINEERING, CIVIL

Marine Structures

Pub Date : 2025-10-15 Epub Date: 2025-07-11 DOI: 10.1016/j.marstruc.2025.103897

Sergey G. Gnezdilov , Alexander N. Shubin

This article presents the results of topology optimization of various non-rotating floating crane solutions. Based on the analysis of classical floating crane solutions, the main types of such cranes have been identified, for which optimization calculation models have been substantiated, which allow us to identify the most rational floating crane solutions. Based on the same modeling principles, models have been prepared and topology optimization of floating cranes located on two separate pontoons has been carried out. The floating crane solution on two pontoons, unlike classical designs, allows for more efficient use of the capabilities of pontoons used in floating cranes. The optimization models proposed in the article also allow for practical recommendations to be prepared on methods for reinforcing pontoon structures of floating cranes.

本文介绍了各种非旋转浮式起重机的拓扑优化结果。在对经典浮式起重机解进行分析的基础上，确定了浮式起重机的主要类型，并对其优化计算模型进行了验证，从而确定了最合理的浮式起重机解。基于相同的建模原理，对位于两个独立浮桥上的浮式起重机进行了建模和拓扑优化。与传统设计不同，两个浮桥上的浮桥解决方案可以更有效地利用浮桥的功能。文中提出的优化模型也为浮式起重机浮桥结构的加固方法提供了实用的建议。

引用次数: 0