Results 31 to 40 of about 1,837 (129)
Analysis of the influence of different damage forms on the residual ultimate strength of ship structure [PDF]
ObjectivesShips are essential for waterborne transportation, and the safety of their structures is of utmost importance. However, during operation, ships may encounter various accidents such as collisions and groundings, which may damage the hull ...
Weiguo WU +2 more
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Research on the time-dependent stability of filling paste under the action of different concentrations of chloride salts [PDF]
In order to study the time-dependent characteristics of filling paste under the action of mine water, chloride salt solutions with mass fraction of 0%, 5%, 10%, and 15% were prepared, and chloride salt dry wet cycle tests with erosion cycles of 4, 8, 12,
Shuaiqian LI, Zhaowen DU, Zhuoyue WEN
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Gaoya dianqi, 2021 文中采用YJV22-8.7/10-3×240mm2XLPE电缆,制作了尖刺缺陷局部放电模型,利用脉冲电流法研究了电缆尖刺缺陷在环境温度为50、70、90℃下的局部放电特性。结果表明,尖刺缺陷放电模型的局部放电起始电压在温度升高时呈下降趋势;缺陷处电缆绝缘横截面切片显示针尖附近出现电树枝,温度升高导致自由基反应加剧,从而使得电树枝的引发电压降低;3种温度下尖刺缺陷PRPD图谱的形貌基本相同,放电相位分布宽泛,极性效应明显;累积放电量和放电重复率随环境温度上升而增加 ...
马鑫 +4 more
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Jianzhu Gangjiegou Jinzhan为探究轨道梁的初始几何缺陷是否会影响轨道梁结构的安全性和是否会加剧台车的卡轨风险，在有限元瞬态分析中提出一种活动屋盖闭合全过程模拟的简化方法，并利用该方法探究了活动屋盖闭合过程中轨道梁位移和应力的变化特征，研究了轨道梁的缺陷类型（z向和y向初始几何缺陷）和缺陷大小对活动屋盖运行的影响。结果表明，在活动屋盖闭合过程中，台车与轨道梁间的y向位移存在一定的差值，该位移差可达3.8 mm以上，且越靠近固定屋盖跨中该位移差越大；不同缺陷类型和缺陷大小下，轨道梁应力比的峰值基本相同，且应力比小于0.54 ...
徐光明 +4 more
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Jianzhu Gangjiegou Jinzhan, 2007 在钢框架二阶弹性分析中,结构整体初始几何缺陷和构件的初始几何缺陷是实际存在的,其影响不可忽略。因此在由单根柱和梁组成的平面子结构二阶弹性理论模型中,引入以上两种几何缺陷,得出了位移与内力的计算公式。利用该理论模型,可以考虑各参数对框架柱二阶效应的影响,并能系统分析框架结构整体几何缺陷与构件几何缺陷对二阶弹性弯矩的影响。
李国强, 侯和涛
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Jianzhu Gangjiegou Jinzhan, 2021 现行《建筑钢结构防火技术规范》(GB 51249—2017)未给出火灾下钢结构的局部稳定设计方法,为了获得轴心受压焊接H形高强Q690钢柱高温下的局部稳定性能,考虑钢材高温下力学性能退化、截面高温下焊接残余应力降低及初始几何缺陷,采用ABAQUS软件建立经试验验证的高温局部稳定分析有限元模型,得到焊接H形高强Q690钢柱在不同温度下的局部屈曲应力和极限应力。研究表明:当温度低于550℃时,钢柱在高温下和常温下屈曲应力具有相同的变化趋势;高温下的残余应力值和初始几何缺陷对屈曲应力有较大的影响 ...
李翔, 王卫永, 于克强
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Probabilistic analysis of mechanical properties for SiC f/SiC composites considering internal damage randomness [PDF]
Ceramic matrix composites（CMCs）experiences internal damage such as fiber pulling out and matrix cracks during usage, which affects the mechanical properties of braided CMCs. For SiCf/SiC 2.5-dimensional braided CMCs, a microscopic finite element model of
LI Hongshuang, XIE Xuexin
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, 1994 对渤海老二号平台１９６８年被大冰推倒这一重大事故进行了全面的调查和分析;描述了平台破坏的全过程。指出平台倒塌是由３个方面的综合因素导致的;而破坏的本质原因是冰激振动产生的疲劳损伤发展到一定程度后;疲劳裂纹的低温脆性扩展而使桩腿失去了承载能力。为此;总结出海冰环境中设计平台的７点经验;供从事我国辽东湾平台的设计、制造 ...
方华灿, 段梦兰, 陈如恒
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Experimental analysis on residual ultimate bearing capacity of thin plate with internal explosion dent damage under biaxial compression [PDF]
ObjectivesIn modern naval warfare, advancements in weaponry have significantly increased the vulnerability of ships to explosion impacts. Precision-guided weapons, in particular, pose a significant threat, as internal explosions within ship cabins can ...
Lei AO +5 more
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Jianzhu Gangjiegou Jinzhan, 2007 在钢框架二阶弹性分析中,结构整体初始几何缺陷和构件的初始几何缺陷是实际存在的,其影响不可忽略。通过平面子结构理论模型进行参数分析,结果证明,对于弱支撑钢框架柱,结构的整体几何缺陷和构件几何缺陷对弯矩的影响均可以等效为作用于楼层处的假想水平力,假想水平力是作用于该楼层的竖向荷载的函数。
侯和涛, 李国强
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