Volume 3: Structures, Safety, and Reliability最新文献_第5页

Dynamic Responses Prediction for a Spar-Type Offshore Floating Wind Turbine Under Ship Collision Scenarios 船舶碰撞情景下桅杆式海上浮式风力机动力响应预测

Volume 3: Structures, Safety, and Reliability Pub Date : 2019-06-09 DOI: 10.1115/omae2019-95094

Yichi Zhang, Zhiqiang Hu

{"title":"Dynamic Responses Prediction for a Spar-Type Offshore Floating Wind Turbine Under Ship Collision Scenarios","authors":"Yichi Zhang, Zhiqiang Hu","doi":"10.1115/omae2019-95094","DOIUrl":"https://doi.org/10.1115/omae2019-95094","url":null,"abstract":"\u0000 A potential collision hazard between offshore floating wind turbines (OFWT) and ships passing-by needs to be paid further attention as more OFWT fields have been designed and will be built in the coming years. In this paper, a theoretical model is proposed to analyze the dynamic responses of a spar-type offshore floating wind turbine under the scenario of ship impact. Firstly, the collision duration is assumed to be quite short and the impact force is assumed to be large enough to assure all other external forces can be ignored temporarily. The hydrodynamic effects are considered by introducing the added mass matrix during the collision process and then on basis of the rigid body impact principle, and the expressions of energy dissipation and some other kinetic characters are derived. Secondly, the dynamic responses of the OFWT after collision are investigated. In this process, external forces which play significant roles will be taken into account. The hydrodynamic forces are estimated using Morison’s Equation with linear wave theory while the wind thrust force is calculated using BEM methods. The mooring system is considered by the simplification to be a linear elastic spring. Finally, based on the theoretical model derived above, a time-domain analytical program is developed, which can be used to evaluate the dynamic responses for the scenario of spar-type OFWT under ship impact scenario. With the newly proposed program, a series of parametric case studies are conducted and by comparing the results, some characters sensitive to them are further discussed.","PeriodicalId":314553,"journal":{"name":"Volume 3: Structures, Safety, and Reliability","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129718564","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Optimal Control for Response Reduction of Single Hinged Articulated Tower Using MR-Damper 基于mr阻尼器的单铰铰接塔响应减小优化控制

Volume 3: Structures, Safety, and Reliability Pub Date : 2019-06-09 DOI: 10.1115/omae2019-96076

K. Solomon, Deepak Kumar

{"title":"Optimal Control for Response Reduction of Single Hinged Articulated Tower Using MR-Damper","authors":"K. Solomon, Deepak Kumar","doi":"10.1115/omae2019-96076","DOIUrl":"https://doi.org/10.1115/omae2019-96076","url":null,"abstract":"\u0000 Articulated tower is a compliant offshore structure deployed in deep waters for oil and gas exploration. The base of the tower is connected to the sea bed through universal joint, which allows the tower to rotate about horizontal axis (pitch). Articulated towers attain stability due to large buoyancy forces acting on it. Under extreme wave loads, the response of ALP can exceed the design limit causing discomfort to the occupants and create unfavourable working conditions. Structural control systems can be implemented in order to reduce the response of ALP, thereby protecting the structure from damages and to increase its life span. In this paper, a semi-active optimal control strategy using Magneto-Rheological damper is adopted to reduce the responses of ALP. Bouc-Wen model is used to describe the force generated by MR-Damper. For achieving the optimal performance of the control system, the applied voltage is varied according to the measured feedback at any moment to change the damping force using linear quadratic regulator technique. Several parametric studies have been conducted and the performance of the controller is evaluated. It is observed that the response of ALP is reduced considerably by using MR-damper as a semi-active control device. However, the capacity of the damper required for achieving the desired control is huge.","PeriodicalId":314553,"journal":{"name":"Volume 3: Structures, Safety, and Reliability","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128542475","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

The Impact of Climate Change on the Long-Term Response of Offshore Structures: A Study Case 气候变化对海洋结构长期响应的影响:一个研究案例

Volume 3: Structures, Safety, and Reliability Pub Date : 2019-06-09 DOI: 10.1115/omae2019-95261

Irvin Alberto Mosquera, L. Sagrilo, P. Videiro

引用次数: 0

Power Spectrum for Surface Description of Corroded Ship Structure From Laser Scan 激光扫描舰船腐蚀结构表面描述的功率谱

Volume 3: Structures, Safety, and Reliability Pub Date : 2019-06-09 DOI: 10.1115/omae2019-95907

K. M. Neumann, S. Ehlers

{"title":"Power Spectrum for Surface Description of Corroded Ship Structure From Laser Scan","authors":"K. M. Neumann, S. Ehlers","doi":"10.1115/omae2019-95907","DOIUrl":"https://doi.org/10.1115/omae2019-95907","url":null,"abstract":"\u0000 Strength of corroded marine structures is in the industry traditionally assessed using average thickness reduction together with the assumption of a uniform surface. In academia it is however realised that the surface texture will influence the strength where the effect of the irregular surface is considered through various parameters such as reduced material properties, roughness, geometrical ratios and thickness distributions. In this paper, the objective is to present a power spectrum which describes the corroded surface topography. Therefore, power spectra of surface and thickness are produced from 3D laser scan of real corroded mild steel specimens from a 30 year old ship using Fast Fourier Transform (FFT). The frequency distribution describes the spatial variability, wherefrom the autocorrelation function (ACF) is deduced. A log-log fit is made to the power spectrum, where the interception with the ordinate axis describes the corrosion severity. This way of describing the surface pattern of the corrosion deterioration may serve as input to novel ways of calculating corroded strength and fatigue initiation as well as simulation of corroded surfaces.","PeriodicalId":314553,"journal":{"name":"Volume 3: Structures, Safety, and Reliability","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132945889","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Axial and Moment Carrying Capacity of Split Sleeve Grouted Connections for Repair of Tubular Members 管状构件修补用裂套注浆连接的轴向承载力和弯矩承载力

Volume 3: Structures, Safety, and Reliability Pub Date : 2019-06-09 DOI: 10.1115/omae2019-96267

N. V. Chellappan, S. Nallayarasu

{"title":"Axial and Moment Carrying Capacity of Split Sleeve Grouted Connections for Repair of Tubular Members","authors":"N. V. Chellappan, S. Nallayarasu","doi":"10.1115/omae2019-96267","DOIUrl":"https://doi.org/10.1115/omae2019-96267","url":null,"abstract":"\u0000 The tubular members damaged by ship impact or falling objects require repair and rehabilitation in offshore structures. The repair of damaged underwater tubular member using welding is hazardous and expensive and hence alternative connection methods such as grouted clamp techniques have been in use for many decades. The existing guideline on the design of grouted connections especially under axial tension and moment is very limited and requires further study. The load transfer mechanism of grouted clamps depends on various geometric parameters and bond between clamp and parent member. A comprehensive study on split sleeve grouted connection for load transfer between two parts of tubular members has been investigated and presented.\u0000 Numerical simulation of split sleeve grouted connection has been carried out using finite element model of tubular member – sleeve through bond strength of grout. The numerical model has been validated using existing guidelines and further parametric study has been carried out. The parametric study includes geometric parameters such as diameter to wall thickness ratio of split sleeve, sleeve friction length, grout strength and grout shrinkage. The simulations have been carried out for combination of axial tension and moment loading.","PeriodicalId":314553,"journal":{"name":"Volume 3: Structures, Safety, and Reliability","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133443674","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

The State-of-the-Art in Structural Integrity Management: A Review and Proposed Data-Driven Approach 结构完整性管理的最新进展:回顾和建议的数据驱动方法

Volume 3: Structures, Safety, and Reliability Pub Date : 2019-06-09 DOI: 10.1115/omae2019-96396

YeongAe Heo

{"title":"The State-of-the-Art in Structural Integrity Management: A Review and Proposed Data-Driven Approach","authors":"YeongAe Heo","doi":"10.1115/omae2019-96396","DOIUrl":"https://doi.org/10.1115/omae2019-96396","url":null,"abstract":"\u0000 Probabilistic risk-based approaches have been used for cost-effective structural design and maintenance guidelines. The effectiveness of these provisions, however, has yet to be adequately validated. Also, current risk management approaches are hardly adaptable to changes in operational and environmental conditions as well as structural properties over the service life of structures. As the need and demand of real-time monitoring systems have increased dramatically for high-value and high-risk facilities such as offshore structures particularly, it is important to discuss directions for future research to advance the risk-based management approaches by utilizing the invaluable “big-scale” field data obtained from sensor network systems. Therefore, knowledge gaps in the current state-of-the-art structural risk management approaches are discussed in this paper. Subsequently, a novel risk management framework is presented in this paper integrating physics-based data into a data-driven decision model. The proposed decision framework will improve system adaptability to future performance requirements due to changing operational and environmental conditions and will be applicable to any structural systems instrumented by sophisticated SHM systems such as complex naval and marine systems.","PeriodicalId":314553,"journal":{"name":"Volume 3: Structures, Safety, and Reliability","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129543588","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Enhancement of Structural Redundancy of Hull Structure in Accidental Condition by Applying Highly Ductile Steel 应用高韧性钢增强意外工况下船体结构冗余度

Volume 3: Structures, Safety, and Reliability Pub Date : 2019-06-09 DOI: 10.1115/omae2019-95912

Shin Nakayama, Ueda Keiji, M. Aoki, Kazuyuki Matsumoto

{"title":"Enhancement of Structural Redundancy of Hull Structure in Accidental Condition by Applying Highly Ductile Steel","authors":"Shin Nakayama, Ueda Keiji, M. Aoki, Kazuyuki Matsumoto","doi":"10.1115/omae2019-95912","DOIUrl":"https://doi.org/10.1115/omae2019-95912","url":null,"abstract":"\u0000 Application of steel plates with highly ductile is beneficial for ship owners, in order to improve structural redundancy and prevent environmental burden in accidental condition such as collision or grounding. Highly ductile steel, in which breaking strain is improved by 20% in comparison with conventional steels has developed, by optimizing microstructure. Excellent ductility was achieved selecting ferrite-perlite dual phase structure of ferrite phase which is advantageous for stable actual production. Morphology of ferrite phase control which consists of optimization of volume fraction and strengthening of ferrite phase itself by adding Si plays an important role to enhance ductility. The highly ductile steel of YP315 grade had acquired Class approval, and for ships to which high ductile steels are applied, ClassNK would assign the notation “Hull Protection by Highly Ductile Steel” (HP-HDS). MITSUBISHI SHIPBUILDING has evaluated the effect of highly ductile steel by numerical simulation for LPG (Liquefied Petroleum Gas) Carrier owned by Astomos Energy Corporation and Iino Kaiun Kaisha, Ltd. It has been confirmed that highly ductile steel can improve the structural redundancy by 20% in accidental condition by being applying to side structure.","PeriodicalId":314553,"journal":{"name":"Volume 3: Structures, Safety, and Reliability","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128292945","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Numerical and Experimental Research on Residual Ultimate Strength of Hull Plates Under Uniaxial Cyclic Loads 单轴循环荷载作用下船体板残余极限强度的数值与试验研究

Volume 3: Structures, Safety, and Reliability Pub Date : 2019-06-09 DOI: 10.1115/omae2019-95226

Tian Xia, Ping Yang, C. Cui, Ziya Peng, L. Ma

引用次数: 0

Two Parameter J-A Estimation for Weld Centerline Cracks in Welded Single-Edge Cracked Plate Under Tensile Loading 拉伸载荷作用下焊接单边裂纹板焊缝中心线裂纹的两参数J-A估计

Volume 3: Structures, Safety, and Reliability Pub Date : 2019-06-09 DOI: 10.1115/omae2019-95392

Chuanjie Duan, Shuhua Zhang

{"title":"Two Parameter J-A Estimation for Weld Centerline Cracks in Welded Single-Edge Cracked Plate Under Tensile Loading","authors":"Chuanjie Duan, Shuhua Zhang","doi":"10.1115/omae2019-95392","DOIUrl":"https://doi.org/10.1115/omae2019-95392","url":null,"abstract":"\u0000 This work examines the J–A two-parameter characterization of elastic–plastic crack front fields for weld centerline cracks under tensile loading. Extensive finite element analyses (FEA) have been conducted to obtain solutions of constraint parameter A, which is the second parameter in a three-term elastic-plastic asymptotic expansion for the stress field near the tip of mode-I crack, for modified boundary layer (MBL) model and welded single-edge cracked plate (SECP). Solutions of the constraint parameter A were obtained for the material following the Ramberg-Osgood power law. The crack geometries analyzed include shallow and deep cracks, and remote tension loading levels cover from small-scale to large-scale yielding conditions. The effects of weld material mismatch and weld width on crack tip constraint were considered in the FEA. A constraint parameter AM, only caused by material strength mismatch, is defined and its parametric equation was obtained. The total constraint in the bi-material weldment can be predicted by adding together AM and A in the homogeneous material. Good agreements were achieved for welded SECP specimen with different crack size and weld width from small-scale to large-scale yielding conditions. This methodology would be useful for performing constraint-based elastic-plastic fracture analyses of other welded test specimens.","PeriodicalId":314553,"journal":{"name":"Volume 3: Structures, Safety, and Reliability","volume":"80 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114919119","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Inner Bend Cracks in Mooring Chain: Investigation of Cracks Observed on Chains Taken Out of Service 锚链内弯曲裂纹:对停用锚链裂缝的研究

Volume 3: Structures, Safety, and Reliability Pub Date : 2019-06-09 DOI: 10.1115/omae2019-95084

Ø. Gabrielsen, I. Kulbotten, I. Pérez, Lars Håskoll

{"title":"Inner Bend Cracks in Mooring Chain: Investigation of Cracks Observed on Chains Taken Out of Service","authors":"Ø. Gabrielsen, I. Kulbotten, I. Pérez, Lars Håskoll","doi":"10.1115/omae2019-95084","DOIUrl":"https://doi.org/10.1115/omae2019-95084","url":null,"abstract":"\u0000 The last decade Equinor has taken a significant amount of mooring chains out of service. Typically, one mooring line for an offshore installation has been replaced. Purpose has been to assess whether current chain condition (corrosion and wear), make the remaining chains fit for further use. The chains have been subject to thorough inspection, break load testing and fatigue testing. Depending on results of the inspection and tests, the remaining mooring chains have either been replaced or found fit for further use.\u0000 From one installation, smaller cracks on the inside of the crown of chain links have been observed. These cracks do not coincide with known fatigue hot spots or fatigue breakages from fatigue testing of chains. Many cracks are visible with the bare eye, and NDT techniques are not necessary for detection. Chains with such cracks have been subject to both break load testing and fatigue testing. Overload breakage and fatigue cracks have not occurred or developed from the cracks. Chain links with cracks have been dissected to investigate crack depth. Dissection has also aimed to assess the age of the cracks. Both chain links that have and have not been subject to full scale fatigue testing have been dissected. This paper presents example of the observed cracks, including details on link location in the mooring line, crack positions in links, and measured depth and length of cracks. The paper also discusses the different possible causes of the cracks, and whether the cracks are critical for the endurance of the chains.","PeriodicalId":314553,"journal":{"name":"Volume 3: Structures, Safety, and Reliability","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115495128","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1