Marine Structures最新文献

{"title":"Active anti-rolling characteristics of fluid momentum wheel for cylindrical FPSO under wave conditions","authors":"Ke-Dong Zhang ,&nbsp;Wen-Hua Wang ,&nbsp;Tai-Wei Piao ,&nbsp;Yi-Hua Liu ,&nbsp;Shu-Dong Leng ,&nbsp;Yuan-Bo Xiu ,&nbsp;Chao-Fan Tu ,&nbsp;Lin-Lin Wang ,&nbsp;Ya-Zhen Du ,&nbsp;Hong-Xia Li ,&nbsp;Yi Huang","doi":"10.1016/j.marstruc.2024.103773","DOIUrl":"10.1016/j.marstruc.2024.103773","url":null,"abstract":"<div><div>In complex sea conditions, floating platforms experience unavoidable roll and pitch motions that impact the efficiency and safety of the crew and equipment. To address the application limitations of gyrostabilizer, the fluid momentum wheel (FMW) based on the angular momentum and precession principle is proposed. The motion responses of a cylindrical floating body in the numerical wave tank are compared with those in an experimental tank to verify the accuracy of the numerical method. Additionally, the results for the coupling model of the floating platform and the FMW demonstrate that the FMW can achieve an effective response reduction, which can be up to 99.64 %. Next, the paper explores the anti-rolling characteristics of the FMW by examining various start-up strategies and arrangement locations, which indicate that the strategy of slow linear growth can enhance the anti-rolling stability and reduce costs. The arrangement location of FMW has a minor impact on the motion control process, highlighting its advantage in adjusting the center of gravity (COG) of the platform. Finally, the FMW demonstrates good applicability across different COGs and geometric configurations, effectively producing stabilizing effects on classic cylindrical platforms with various parameters. These findings evidence the ability of the FMW to reduce pitch motion responses of floating platforms, providing a basis for its potential application on offshore platforms.</div></div>","PeriodicalId":49879,"journal":{"name":"Marine Structures","volume":"101 ","pages":"Article 103773"},"PeriodicalIF":4.0,"publicationDate":"2025-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143147708","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhancing the real-time prediction of fatigue damage in offshore structures: A novel method integrating frequency-domain approaches","authors":"Haiyang Ge ,&nbsp;Xin Li ,&nbsp;Wenyue Lu ,&nbsp;Bo Wu ,&nbsp;Yunlong Jiang","doi":"10.1016/j.marstruc.2024.103772","DOIUrl":"10.1016/j.marstruc.2024.103772","url":null,"abstract":"<div><div>Offshore structures are continuously subjected to wideband random loads, rendering the real-time prediction and assessment of their fatigue life a challenge. Thus far, a high-confidence method for predicting fatigue damage, referred to as rain-flow counting (RFC), has failed to perform real-time damage prediction in actual offshore operation scenarios owing to its large computing time and input data size. In this study, an improved fatigue damage estimation method is proposed for real-time prediction in the frequency domain by constructing standard stress spectrum to determine the distribution parameters, weight factors, and distribution correction coefficients associated with the spectrum width parameters. A new assembly distribution is applied using a weighted combination of exponential, half-Gaussian, and two double-parameter Weibull distributions. Based on the established standard stress spectra, the proposed method was compared with RFC to preliminarily verify its prediction accuracy. Subsequently, the proposed method was applied to actual ship monitoring and compared with nine typical prediction methods; the results confirmed the satisfactory prediction accuracy and stability of the developed model. In conclusion, the high-precision predictions made by the developed method closely match the RFC results, significantly improving the fatigue damage prediction over various bandwidth processes.</div></div>","PeriodicalId":49879,"journal":{"name":"Marine Structures","volume":"101 ","pages":"Article 103772"},"PeriodicalIF":4.0,"publicationDate":"2025-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143147800","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A frequency-domain optimization procedure for catenary and semi-taut mooring systems of floating wind turbines","authors":"Serag-Eldin Abdelmoteleb,&nbsp;Erin E. Bachynski-Polić","doi":"10.1016/j.marstruc.2024.103768","DOIUrl":"10.1016/j.marstruc.2024.103768","url":null,"abstract":"<div><div>This work presents an efficient method for assessing mooring system designs for floating wind turbines (FWTs) based on frequency-domain analysis. The method is used to explore the design space and design-driving constraints for catenary and semi-taut mooring systems for semi-submersible FWTs with power ratings from 5 to 25 MW. The proposed method combines a previously presented model for low-frequency rotor-aero-servo dynamics in frequency-domain with a frequency-domain lumped mass model for estimating the wave-frequency dynamic tension, which has often been treated quasi-statically in previous studies. Multiple design constraints including ultimate limit state, fatigue limit state, and maximum allowable offset were considered in design space exploration and optimization. The main design-driving criteria were found to be the maximum offset and fatigue life. The resulting designs were tested using nonlinear coupled time-domain analysis and found to satisfy all the required design criteria. The frequency-domain model captures the main trends of the motion and tension statistics of the FWTs while providing conservative estimates for fatigue damage for most conditions. The discrepancies between the frequency- and time-domain results are mainly due to overestimation of the surge resonance response due to the linearization of aerodynamic damping in the frequency-domain model.</div></div>","PeriodicalId":49879,"journal":{"name":"Marine Structures","volume":"101 ","pages":"Article 103768"},"PeriodicalIF":4.0,"publicationDate":"2025-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143147716","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ultimate bearing capacity and fatigue life analysis of marine sandwich composite bolted connection structure: Fatigue test and numerical simulation","authors":"Yu Qiu ,&nbsp;RenJun Yan ,&nbsp;Jiajing Lei ,&nbsp;Gongrong Li ,&nbsp;Wei Shen ,&nbsp;Yaoyu Hu","doi":"10.1016/j.marstruc.2024.103770","DOIUrl":"10.1016/j.marstruc.2024.103770","url":null,"abstract":"<div><div>Because of the great difference in performance between component materials, there are some problems in sandwich composite structures, such as complex fatigue failure mode and difficult observation of internal damage. The numerical simulation method of fatigue can effectively simulate the whole process of fatigue failure. At present, the fatigue failure prediction methods of reinforced fiber laminates and interlayer interfaces are effectively analyzed, but there is no relevant numerical simulation method that can consider the fatigue failure of core materials. Based on the fatigue test data of foam core materials, an improved fatigue life prediction method of foam core material with principal stress and Tresca stress as basic parameters is proposed, and a progressive failure fatigue analysis method of foam sandwich composite structure is formed by combining the stiffness/strength degradation model of fiber reinforced laminates and Shokrieh fatigue failure criterion. Based on the finite element calculation software ABAQUS, the corresponding UMAT subroutine is compiled and the fatigue life and damage mode prediction of the sandwich composite bolted connection structure are verified. Compared with the experimental results, it can be found that the proposed finite element fatigue analysis method has high calculation accuracy and can be used to guide the anti-fatigue design and optimization of sandwich composite structures.</div></div>","PeriodicalId":49879,"journal":{"name":"Marine Structures","volume":"101 ","pages":"Article 103770"},"PeriodicalIF":4.0,"publicationDate":"2024-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143147715","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Long-term cyclic performance of offshore jacked piles in structured clays: Insights from model testing","authors":"Pan Zhou ,&nbsp;Feng Dai ,&nbsp;Shanghui Yang ,&nbsp;Yi Liu ,&nbsp;Zelin Yan ,&nbsp;Mingdong Wei","doi":"10.1016/j.marstruc.2024.103769","DOIUrl":"10.1016/j.marstruc.2024.103769","url":null,"abstract":"<div><div>Marine soft clays are known for their poor engineering properties, which, when subjected to prolonged static and dynamic loading, can lead to excessive settlement of offshore pile foundations and subsequent structural instability, resulting in frequent engineering failures. This study examines the bearing and deformation behavior of jacked piles in these clay deposits under both static and cyclic loading conditions using a custom-designed model testing apparatus. Emphasizing the time-dependent load-carrying capacity and accumulated cyclic settlement of piles, the research uses artificially structured clay to more accurately simulate stratum conditions than traditional severely disturbed natural clays. Model pile testing was carried out to analyze the effects of soil structure and cyclic loading patterns on the long-term response of jacked piles. Key factors investigated include initial soil structure, pile jacking-induced destruction, soil reconsolidation post-installation, disturbed clay's thixotropic effects, and cyclic loading's impact during service. Results show that increasing the cement content within the clays from 0 % to 4 % nearly doubled pile penetration resistance, led to a more significant accumulation of excess pore water pressure (EPWP), and accelerated its dissipation rate. Additionally, the ultimate load-carrying capacity of jacked piles also doubled. Higher cement content slowed pile head settlement rates and reduced stable cumulative settlement values, requiring more cycles to reach instability. Under high-amplitude, low-frequency cyclic loads, hysteresis loops of the model piles became more pronounced and rapid. This study enhances understanding of the long-term cyclic behavior of jacked piles in soft soils, providing valuable insights for designing offshore piles.</div></div>","PeriodicalId":49879,"journal":{"name":"Marine Structures","volume":"101 ","pages":"Article 103769"},"PeriodicalIF":4.0,"publicationDate":"2024-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143147664","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A CPT-based p-y model for laterally loaded monopiles in sand","authors":"Zhentao Liu,&nbsp;Youhu Zhang,&nbsp;Peng Guo","doi":"10.1016/j.marstruc.2024.103767","DOIUrl":"10.1016/j.marstruc.2024.103767","url":null,"abstract":"<div><div>Large-diameter monopiles are currently the dominant foundation solution for supporting offshore wind turbines (OWTs). Monopiles exhibit a rigid response with significant rotation under lateral load and overturning moment. There is some debate regarding the applicability of <em>p-y</em> models derived from tests on small-diameter slender piles (such as the sand <em>p-y</em> model recommended by the API standard) to monopiles. To address this issue, this study gathered existing field pile load tests and finite element analysis results for large-diameter monopiles in sand and established a database incorporating the CPT results from each testing site. Through a comprehensive analysis of the collected database, a CPT-based <em>p-y</em> model with a modified hyperbolic formulation is proposed. The model has four parameters, which are the initial soil-pile interaction stiffness (<em>k</em>_ini), the ultimate soil resistance (<em>p</em>_u), the stiffness degradation coefficient (<em>m</em>), and the ultimate soil resistance adjustment coefficient (<em>A</em>). All of them are functions of the CPT cone tip resistance (<em>q</em>_c), thus avoiding potential uncertainties with the determination of input soil parameters, such as the peak friction angle, which is necessary for the conventional API <em>p-y</em> model. The model is demonstrated to provide satisfactory performance in predicting the lateral response of monopiles in sand.</div></div>","PeriodicalId":49879,"journal":{"name":"Marine Structures","volume":"101 ","pages":"Article 103767"},"PeriodicalIF":4.0,"publicationDate":"2024-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143147714","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Risk assessment of the erosive process in the production pipeline of an Wet Christmas Tree as an indicator for inspection request","authors":"Vinícius Bellincanta Hercos,&nbsp;Miguel Luiz Ribeiro Ferreira","doi":"10.1016/j.marstruc.2024.103765","DOIUrl":"10.1016/j.marstruc.2024.103765","url":null,"abstract":"<div><div>Wet Christmas Trees (WCTs) pipes are susceptible to erosion owing to the presence of solid particles in the oil. The thickness measurements of these pipes are performed using remotely operated vehicles (ROVs). This study aims to assess the risk of leakage caused only by erosion, specifically for curved sections, based on the Det Norske Veritas (DNV) methodology. Data processing was performed using the Monte Carlo method by utilizing the operational and design data from a WCT with the aid of @Risk 8.2 software. The results demonstrate that the risk of leakage is too low, mainly because the design of the pipes of this WCT is conservative. However, the operator is responsible for determining their tolerance level and scheduling inspections accordingly. Through sensitivity analysis, was observed that an increase in sand content, water, oil, and gas flow rates most significantly impacted thickness reduction due to erosion.</div></div>","PeriodicalId":49879,"journal":{"name":"Marine Structures","volume":"101 ","pages":"Article 103765"},"PeriodicalIF":4.0,"publicationDate":"2024-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143147713","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Water impact damage considering hydro-plastic interactions: Extensive experimental and numerical validation, and structural design recommendations","authors":"Zhaolong Yu","doi":"10.1016/j.marstruc.2024.103766","DOIUrl":"10.1016/j.marstruc.2024.103766","url":null,"abstract":"<div><div>Water impact damage can occur for ocean structures subjected to extreme waves as well as aeronautical vehicles during emergency water landing. The problem involves complicated fluid structure interaction (FSI) effects between large plastic structural deformations and fluid flow pressures, known as hydro-plasticity, and is not well understood. In 2019, we (Yu et al. [1]) derived a novel hydroplastic solution for water impact damage of beams and stiffened panels considering the mutual coupling effect. This paper utilizes results from model tests, real world wave impact accidents and coupled FSI numerical simulations to verify comprehensively the accuracy of the hydroplastic model in terms of the predicted structural damage and pressure histories. As most design standards use suggested pressure curves for designing against extreme wave impacts in the maritime and offshore industries, the pressure histories predicted by the hydroplastic model are reapplied to the structures to calculate the structural responses using nonlinear finite element analysis (NLFEA). This is to test if the generated pressure histories can reproduce the water impact damage and be used as suggested design pressure curves. Finally, a new design method is suggested based on the hydroplastic slamming model for the design of ocean structures against extreme wave impacts. The proposed design approach suggests using impact velocities rather than design pressures in current design standards, as the main design parameter, the value of which should meet required annual exceedance probability levels. The proposed design approach represents clear improvement and is useful for reliable and cost-effective design of structures against extreme water impacts.</div></div>","PeriodicalId":49879,"journal":{"name":"Marine Structures","volume":"101 ","pages":"Article 103766"},"PeriodicalIF":4.0,"publicationDate":"2024-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143147712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Highlights and future research areas from ISSC 2022","authors":"Xiaozhi Wang ,&nbsp;Ole Andreas Hermundstad ,&nbsp;James Underwood ,&nbsp;Yordan Garbatov ,&nbsp;Sören Ehlers ,&nbsp;B Lennart Josefson ,&nbsp;Athanasios Kolios ,&nbsp;Iraklis Lazakis ,&nbsp;Agnes Marie Horn ,&nbsp;Neil Pegg","doi":"10.1016/j.marstruc.2024.103746","DOIUrl":"10.1016/j.marstruc.2024.103746","url":null,"abstract":"<div><div>The International Ship and Offshore Structures Congress 2022 (ISSC 2022) held in September 2022 covered most of the essential topics related to marine and offshore structures. The proceedings of ISSC 2022 include Committee Reports for Environment, Loads, Quasi-Static Response, Dynamic Response, Ultimate strength, Fatigue and Fracture, Design Principles and Criteria, Design Methods, Accidental Limit States, Experiment Methods, Materials and Fabrication Technology, Offshore Renewable Energy, Special Vessels, Ocean Space Utilization, Structural Longevity and Subsea Technology [<span><span>1</span></span>,<span><span>2</span></span>,<span><span>3</span></span>]. While the nature of ISSC Committee work is focused on state-of-the-art review based on the latest publications, the future work and research areas, which are most relevant to stimulate more R&amp;D effort, are presented here, focusing on Loads, Quasi-static response, Fatigue and fracture, Experimental method, Material and fabrication technology, Offshore renewable energy, Structural longevity, and Subsea technology.</div></div>","PeriodicalId":49879,"journal":{"name":"Marine Structures","volume":"101 ","pages":"Article 103746"},"PeriodicalIF":4.0,"publicationDate":"2024-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143147663","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical investigation of flow-induced vibrations in two tandem circular cylinders at low gap ratios with considering collisions","authors":"Guosheng Qi ,&nbsp;Xiangxi Han ,&nbsp;Junlong Su ,&nbsp;Di Ren ,&nbsp;Zhanbin Meng ,&nbsp;Jian Gu ,&nbsp;Youhong Tang ,&nbsp;Zekun Hu ,&nbsp;Weidong Ruan","doi":"10.1016/j.marstruc.2024.103758","DOIUrl":"10.1016/j.marstruc.2024.103758","url":null,"abstract":"<div><div>In this study, two tandem elastically supported cylinders with the same parameters undergo numerical simulations using the overset grid method to analyze flow-induced vibrations (FIVs) with two degrees of freedom (2DOF). This study presents a model that can consider the collision of two tandem circular cylinders with FIVs in order to systematically analyze the FIV response, hydrodynamic characteristics, and wake vortex shedding patterns of two tandem circular cylinders with varying gaps of 0.5<em>D</em>, 1.0<em>D</em>, and 1.5<em>D</em>. The critical collision gap was found to be 1.6<em>D</em> for the 2 DOF FIV of two tandem circular cylinders. ​At each initial gap ratio, the streamwise amplitude of the upstream cylinder closely matches that of the isolated cylinder at lower reduced velocities (<em>U_r</em> ≤8.0), but increases significantly at higher reduced velocities (<em>U_r</em> &gt;8.3). Furthermore, the reduced velocity at which the downstream cylinder reaches its maximum transverse amplitude exceeds that of the isolated cylinder. For the large initial gap ratios (<em>G</em> = 1.0<em>D</em>, 1.5<em>D</em>), the transverse vibration frequency ratios of the upstream and downstream cylinders are close to those of the isolated cylinder. However, the reduced velocity at frequency ratio <em>f_y</em>/<em>f_n</em> equal to 1.3 is larger compared to the isolated cylinder case, and the delay effect becomes more noticeable as the initial gap ratio decreases. The upstream cylinder presents a figure 8 vibration trajectory only for small reduced velocities (<em>U_r</em> ≤7.0) and large gap ratios (<em>G</em>/<em>D</em> = 1.0, 1.5). However, in the range of reduced velocity and gap ratio considered in this study, the downstream cylinder exhibits chaotic vibration trajectories. For an initial gap of <em>G</em> = 0.5<em>D</em>, both the collision frequency and collision force between the upstream and downstream cylinders increase with increasing reduced velocities. As the initial gap ratio increases, the collision frequency and the collision force of the two cylinders decrease. The flow patterns of the two cylinders are mainly the shear layer reattachment flow pattern and the shear layer embedding flow pattern at small initial gap ratio. With the increase of the initial gap ratio, the synchronized gap vortex shedding flow pattern gradually occupies the dominant position. When the initial gap <em>G</em> = 0.5<em>D</em>, the wake vortex shedding patterns of the upstream and downstream cylinders are essentially 2S. When the initial gap <em>G</em> = 1.5<em>D</em>, both upstream and downstream cylinders can form super upper branches with 2T wake vortex shedding pattern, and the maximum transverse amplitude of the downstream cylinder reaches 1.73<em>D</em>.</div></div>","PeriodicalId":49879,"journal":{"name":"Marine Structures","volume":"101 ","pages":"Article 103758"},"PeriodicalIF":4.0,"publicationDate":"2024-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143147711","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}