The dynamic stiffness of polyester rope presents a complex mechanical performance,and the search for an appropriate calculation method to simulate this property is important.Distorted simulation results eventually yie...The dynamic stiffness of polyester rope presents a complex mechanical performance,and the search for an appropriate calculation method to simulate this property is important.Distorted simulation results eventually yield inaccurate line tension and vessel offset predictions,with the inaccuracy of vessel offset being particularly large.This paper proposes a flexible calculation method for the dynamic behavior of polyester rope based on the dynamic stiffness model.A real-time varying stiffness model of polyester rope is employed to simulate tension response through rope strain monitoring.Consequently,a simulation program is developed,and related case studies are conducted to explore the differences between the proposed method and analytical procedure of the DNV standard.Orcaflex is used to simulate the results of the latter procedure for comparison.Results show the convenience and straightforwardness of the procedure in the selection of an approximate dynamic stiffness model for polyester rope,which leads to an engineering-oriented approach.However,the proposed method is related to line property,which can directly reflect the dynamic behavior of polyester rope.Thus,a flexible calculation method may provide a reference for the simulation of the dynamic response of polyester mooring systems.展开更多
近30年来电缆绝缘材料、半导电屏蔽材料的发展和电缆生产工艺的进步为高压交联聚乙烯(XLPE)电缆绝缘优化设计提供了基础。为了降低中国高压XLPE电缆生产和应用水平同国外先进水平的差距,对代表国内技术水平的电缆样品开展了逐级击穿试...近30年来电缆绝缘材料、半导电屏蔽材料的发展和电缆生产工艺的进步为高压交联聚乙烯(XLPE)电缆绝缘优化设计提供了基础。为了降低中国高压XLPE电缆生产和应用水平同国外先进水平的差距,对代表国内技术水平的电缆样品开展了逐级击穿试验和寿命指数试验,确定了110 k V和220 k V电缆样品的最小击穿强度和寿命指数,进而对高压XLPE电缆绝缘厚度进行优化设计,提出了110 k V和220 k V高压XLPE电缆优化后绝缘厚度分别为13.5 mm和21.0 mm。对绝缘厚度优化后的电缆进行了电场计算和型式试验,计算和试验结果表明优化后的电缆可靠性满足要求。展开更多
目前回弹法规程只适用于60 MPa以下强度等级混凝土强度的检测,针对高强混凝土的特点,采用本地区具有代表性的原材料,制作了C50、C55、C60、C65、C70、C75、C80高强混凝土试块,分为14、28、60、90、180、365 d 6个龄期进行测试,利用最小...目前回弹法规程只适用于60 MPa以下强度等级混凝土强度的检测,针对高强混凝土的特点,采用本地区具有代表性的原材料,制作了C50、C55、C60、C65、C70、C75、C80高强混凝土试块,分为14、28、60、90、180、365 d 6个龄期进行测试,利用最小二乘方法,得到了4种不同函数形式的回归方程。通过相关系数、相对标准误差和平均相对误差的比较,线性函数型的回归效果最好,精度最高,采用其作为本地区高强混凝土回弹法地方测强曲线。展开更多
基金supported by the National Natural Science Foundation of China(Grant No.51879047).
文摘The dynamic stiffness of polyester rope presents a complex mechanical performance,and the search for an appropriate calculation method to simulate this property is important.Distorted simulation results eventually yield inaccurate line tension and vessel offset predictions,with the inaccuracy of vessel offset being particularly large.This paper proposes a flexible calculation method for the dynamic behavior of polyester rope based on the dynamic stiffness model.A real-time varying stiffness model of polyester rope is employed to simulate tension response through rope strain monitoring.Consequently,a simulation program is developed,and related case studies are conducted to explore the differences between the proposed method and analytical procedure of the DNV standard.Orcaflex is used to simulate the results of the latter procedure for comparison.Results show the convenience and straightforwardness of the procedure in the selection of an approximate dynamic stiffness model for polyester rope,which leads to an engineering-oriented approach.However,the proposed method is related to line property,which can directly reflect the dynamic behavior of polyester rope.Thus,a flexible calculation method may provide a reference for the simulation of the dynamic response of polyester mooring systems.
文摘近30年来电缆绝缘材料、半导电屏蔽材料的发展和电缆生产工艺的进步为高压交联聚乙烯(XLPE)电缆绝缘优化设计提供了基础。为了降低中国高压XLPE电缆生产和应用水平同国外先进水平的差距,对代表国内技术水平的电缆样品开展了逐级击穿试验和寿命指数试验,确定了110 k V和220 k V电缆样品的最小击穿强度和寿命指数,进而对高压XLPE电缆绝缘厚度进行优化设计,提出了110 k V和220 k V高压XLPE电缆优化后绝缘厚度分别为13.5 mm和21.0 mm。对绝缘厚度优化后的电缆进行了电场计算和型式试验,计算和试验结果表明优化后的电缆可靠性满足要求。
文摘目前回弹法规程只适用于60 MPa以下强度等级混凝土强度的检测,针对高强混凝土的特点,采用本地区具有代表性的原材料,制作了C50、C55、C60、C65、C70、C75、C80高强混凝土试块,分为14、28、60、90、180、365 d 6个龄期进行测试,利用最小二乘方法,得到了4种不同函数形式的回归方程。通过相关系数、相对标准误差和平均相对误差的比较,线性函数型的回归效果最好,精度最高,采用其作为本地区高强混凝土回弹法地方测强曲线。