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水下钻孔爆破水中冲击波的数值模拟研究

水电能源科学 2009年第4期27卷 138-141,214页

作者：高明涛李昕周晶大连理工大学海岸和近海工程国家重点试验室辽宁大连116024

运用ANSYS/LS-DYNA3D程序模拟了水下钻孔爆破产生的冲击波传播过程,得到了地震动水压力和冲击波的波形曲线及压力数据,分析了其特性及传播规律,并利用Cole经验公式拟合模拟了取得的数据。结果表明,在与炮孔轴线夹角约45°范围内,地震动... 详细信息

运用ANSYS/LS-DYNA3D程序模拟了水下钻孔爆破产生的冲击波传播过程,得到了地震动水压力和冲击波的波形曲线及压力数据,分析了其特性及传播规律,并利用Cole经验公式拟合模拟了取得的数据。结果表明,在与炮孔轴线夹角约45°范围内,地震动水压力与冲击波叠加使冲击波峰值压力随爆距增加单调减小,Cole经验公式对水下钻孔爆破产生的地震动水压力和冲击波的传播规律均具有良好的适应性。

关键词：水下钻孔爆破冲击波地震动水压力数值模拟 LS-DYNA

Study of damage to a high concrete dam subjected to underwater shock waves

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Earthquake engineering and engineering Vibration 2014年第2期13卷 337-346页

作者： Lu Lu li xin zhou jing Faculty of Architecture and Civil engineering Huaiyin Institute of Technology The state key laboratory of coastal and offshore engineering Dalian University of Technology

To study the effect of a strong underwater shock wave on a concrete dam, this research aims to improve hammer impact methods in model tests. Six 1:200 scale models were designed and tested under distributed impact loads. A device was deployed for a direct measurement of the impact force at the upstream face of the dams. The model dam bases were anchored to prevent displacement. The experimental results indicate that the top part of the concrete dam is a weak zone, and the impact failure initiates with a fracture on the top of the dam. The peak value of impact stress increases when the second crack appears in the concrete dam from the upstream face to the downstream face. And, the level of the second crack in the dam body is lower as the peak value of impact stress increases. In this study, dynamic analysis was conducted by calculating the results to verify the effectiveness of a device to directly measure the impact force. This method may be used to approximately forecast the damage of concrete dam and may also be useful in other engineering applications.

关键词： underwater shock wave hammer impact impact force high concrete gravity dam forecast damage

Property of Corroded Concrete under Compressive Uniaxial Loads

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Journal of Wuhan university of technology(Materials Science) 2008年第2期23卷 276-280页

作者： FAN Yingfang HU Zhiqiang zhou jing li xin Institute of Road and Bridge engineering Dalian Maritime University Dalian 116026 China state key laboratory of coastal and offshore engineering Dalian University of Technology Dalian 116024 China

In order to study the compressive property of corroded concrete, accelerated corrosion test were performed on concrete C30.6 corrosive solutions, including hydraulic acid solution （pH=2）, hydraulic acid solution （pH=3） were applied as the corrosive medium. 6 series of corrosion tests, including 111 specimens, were carried out. Mechanical properties of all the corroded specimens were tested respectively. Compressive properties of the corroded specimens （e.g. compressive strength, stress-strain relation, elastic modulus etc.） were achieved. Taking the strength degradation ratio and strain energy loss as damage index, effects of the corrosion solution on the compressive property of corroded concrete were discussed in detail. Relationship between the damage index and corrosion state of specimens were achieved.

关键词： concrete corrosion compressive strength elastic modulus stress-strain curve strain energy loss

基于CEM-FEM耦合方法的海上风力机抗冰和振动控制研究

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太阳能学报 2024年第1期45卷 179-187页

作者：柳英洲施伟李颖周利王滨李昕大连理工大学建设工程学部水利工程学院抗震研究所大连116024 大连理工大学海岸与近海工程国家重点实验室大连116024 大连理工大学深海工程研究中心大连116024 浙江科技学院中德工程师学院杭州310023 江苏科技大学船舶与海洋工程学院镇江212003 浙江省深远海风电技术研究重点实验室杭州311122 中国电建集团华东勘测设计研究院有限公司杭州311122 大连理工大学宁波研究院宁波315000

冰荷载是影响海上风力机安全运行的重要决定性因素,严重时会致使海上风力机结构发生冰激振动破坏和冰激疲劳失效。该研究基于粘聚单元(cohesive element method,CEM)-有限元(finite element method,FEM)耦合方法,通过非线性分布弹簧考虑... 详细信息

冰荷载是影响海上风力机安全运行的重要决定性因素,严重时会致使海上风力机结构发生冰激振动破坏和冰激疲劳失效。该研究基于粘聚单元(cohesive element method,CEM)-有限元(finite element method,FEM)耦合方法,通过非线性分布弹簧考虑桩-土相互作用,建立海冰-寒区单桩海上风力机结构在风-冰联合作用下的整体耦合冰激振动非线性有限元模型。进而,基于非线性数值仿真工具LS-DYNA,分别模拟冰与直立结构和带有抗冰锥的基础结构相互作用过程,并与现有的挤压和弯曲冰力模型进行对比,验证该研究模拟动冰荷载的准确性,讨论两种冰破坏模式下动冰荷载的变化规律。最后,为解决海上风力机发生的强烈冰激振动问题,分别采用振动控制方法和施加抗冰锥的方式,开展风、冰联合作用下海上风力机动冰力和动力响应研究,对比分析以上两种减振方式的减振机理和减振效果差异。结果表明,虽然抗冰锥可明显降低冰-海上风力机相互作用的动冰荷载幅值,然而采用振动控制策略的海上风力机减振效果明显优于抗冰锥。因此,在海上风力机的冰激结构损伤研究和抗冰设计中必须分别考虑以上两种减振方式对结构的影响。

关键词：海冰风场海上风力机桩基础粘聚单元方法振动控制

Failure Pressure Analysis of Corroded Moderate-to-High Strength Pipelines

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china Ocean engineering 2016年第1期30卷 69-82页

作者：苏晨亮李昕周晶 state key laboratory of coastal and offshore engineering Dalian University of Technology

Based on the elastic-plastic, large-deformation finite element method, burst capacity of steel pipeline with longitudinal corrosion defect subjected to internal pressure is studied. The appropriate stress-based criterion is used to predict the failure pressure of finite element model of corroded pipeline under internal pressure. By considering the pipe steel grades and geometries of corrosion defects, a series of finite element analyses is conducted. The effects of corrosion depth, length and width on burst capacity are also discussed. A specific failure pressure solution for the assessment of corrosion defects in moderate-to-high strength pipeline is proposed on the base of numerical results. The failure pressures predicted by the proposed method are in better agreement with the experimental results than the results by the other methods.

关键词： steel pipeline stress-based criteria failure pressure effect of corrosion width

METHODS FOR IDENTIFYING SUB-REGIONAL MATERIAL PARAMETERS OF CONCRETE DAMS USING MODAL DATA

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Acta Mechanica Solida Sinica 2003年第1期16卷 88-94页

作者： Feng xin zhou jing Fan Yingfang Department of Building engineering Tongji UniversityShanghai 200092China state key Lab of offshore■coastal engineering Department of Civil EngineeringDalian University of TechnologyDalian 116024China

Methods for identifying sub-regional material parameters of concrete damsusing incomplete rnodal data are presented. With the measurements of the first frequency andincomplete mode shape, identification methods were built by both the output error approach and theminimum deviation approach. The minimum deviation approach was introduced as physical constraints tothe output error approach, allowing the output error-minimum deviation coupled approach to bedeveloped. The simulated annealing-simplex shape algorithm was applied to solve the identificationmodels. Numerical simulations were carried out with noisy incomplete measurements to illustrate therobustness of the methods.

关键词： concrete dam parameter identification output error approach minimumdeviation approach simulated annealing-simplex shape algorithm

Ultimate Load Capacity of offshore Pipeline with Arbitrary Shape Corrosion Defects

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china Ocean engineering 2015年第2期29卷 241-252页

作者：陈严飞张娟张宏刘啸奔李昕周晶曹静 National engineering laboratory for Pipeline Safety/Beijing key laboratory of Urban Oil and Gas Distribution technology China University of Petroleum Power china Beijing engineering Corporation limited state key laboratory of coastal and offshore engineering Dalian University of Technology CNOOC Research Institute

A set of generalized solutions are proposed for estimating ultimate load capacity of pipeline with arbitrary corrosion shapes subjected to combined internal pressure, axial force and bending moment. Isotropic and anisotropic material characteristics in longitudinal and circumferential direction of pipeline are also considered in the proposed equations. Simplified numerical method is used to solve the generalized expressions. The comparisons of numerical results based generalized solutions and full-scale experimental results are carried out. The predicted results agree reasonably well with the experiment results. Meanwhile, the effects of corrosion shapes and locations on the ultimate load capacity are studied.

关键词： offshore pipeline arbitrary shaped corrosion defects ultimate load capacity combined loads

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冬季南海北部陆架锋区悬浮颗粒态硅的分析

海洋学报 2009年第5期31卷 31-39页

作者：鲁超刘素美任景玲陈琪罗忻李建兵张经中国海洋大学海洋化学理论与工程技术教育部重点实验室山东青岛266100 国家海洋局第二海洋研究所海洋动力和卫星遥感重点实验室浙江杭州310012 华东师范大学河口海岸动力沉积和动力地貌综合国家重点实验室上海200062

对冬季南海北部陆架锋区的悬浮颗粒态生物硅(Particulate Biogenic Silica,PBSi)和成岩硅(lithogenic Silica,LSi)含量进行了调查分析,讨论了悬浮颗粒态生物硅分布及其影响因素。结果表明,南海北部陆架区悬浮颗粒态生物硅和成岩硅平均... 详细信息

对冬季南海北部陆架锋区的悬浮颗粒态生物硅(Particulate Biogenic Silica,PBSi)和成岩硅(lithogenic Silica,LSi)含量进行了调查分析,讨论了悬浮颗粒态生物硅分布及其影响因素。结果表明,南海北部陆架区悬浮颗粒态生物硅和成岩硅平均含量分别为0.59和8.93μmol/dm3。生物硅分布与水团关系密切:在营养盐充足的沿岸水生物硅含量高(1.0μmol/dm3);而在营养盐缺乏的陆架表层水生物硅含量低(0.23μmol/dm3);在两种水团过渡区生物硅含量居中(0.65μmol/dm3)并与溶解硅酸盐(Dissolved Silicate,DSi)成显著正相关(R=0.48,N=44,P=0.001,a=0.01)。此外锋面位置也直接影响生物硅的含量与分布。大部分调查海区被高温高盐低营养盐海水占据,因此导致了调查海区以低浓度的生物硅和成岩硅为特征,且与世界其他海区相比,生物硅含量处于低值区。

关键词：生物硅成岩硅分布陆架锋南海北部

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腐蚀管道在内压和轴向压力影响下的弯曲破坏

海洋工程 2016年第6期34卷 74-82页

作者：高杰李昕周晶大连理工大学海岸和近海工程国家重点实验室辽宁大连116024

运行在恶劣环境中的海底管道,往往受到内压、轴力和弯矩等复杂荷载的联合作用。腐蚀会导致管壁局部变薄,降低管道极限承载力。为保证管道安全高效运行,准确预测和分析复杂荷载作用下的塑性极限承载力和变形行为就显得尤为重要。考虑大... 详细信息

运行在恶劣环境中的海底管道,往往受到内压、轴力和弯矩等复杂荷载的联合作用。腐蚀会导致管壁局部变薄,降低管道极限承载力。为保证管道安全高效运行,准确预测和分析复杂荷载作用下的塑性极限承载力和变形行为就显得尤为重要。考虑大应变和大变形、应力强化和材料非线性,运用数值仿真软件建立腐蚀缺陷管道的三维实体有限元模型,在全尺寸管道破坏试验验证的基础上,对腐蚀管道在内压、轴向压力和弯矩相互作用下的失效模式和极限弯矩承载力进行了相关研究,并进行了腐蚀缺陷几何参数的敏感性分析。研究结果表明:初始内压和初始轴向压力会显著降低腐蚀管道的极限弯矩承载力,并且影响最终的失效模式;在腐蚀缺陷几何尺寸参数中,腐蚀宽度比腐蚀深度和腐蚀长度的影响更大。

关键词：钢质管道腐蚀缺陷数值仿真复杂荷载失效模式极限承载力