Results 21 to 30 of about 1,293 (161)
随机变幅载荷下焊接接头的海水腐蚀疲劳裂纹扩展试验 [PDF]
, 1994 本工作采用国产海上平台用钢的T型和十字形板状焊接接头试件;模拟导管架管节点的弯曲受力状态;在随机变幅载荷下进行了海水腐蚀疲劳裂纹扩展试验;分别测得在海水自由腐蚀和阴极保护条件下的da/dN～△K_(rms)关系曲线。对于十字型焊接接头试件;根据试验测得的裂纹扩展速率曲线;用断裂力学方法对其海水腐蚀疲劳裂纹扩展寿命(有阴极保护)进行了估算 ...
徐纪林, 李禾, 薛以年
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An integrated DIC and CPG investigation of the model-I fracture features for granites after cyclic heating-cooling treatments [PDF]
The thermo-mechanical properties of deep reservoir rocks, especially the damage and failure characteristics under heating-cooling cycles, are of great importance to the stability analysis of well wall and the evaluation of geothermal extraction ...
Gan FENG +5 more
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Research progress on fracture control of accidental leakage and decompression in CO2 pipeline transportation [PDF]
, 2022 Pipeline is the optimal way in transporting large amounts of carbon dioxide (CO2) in CCUS (carbon capture, utilization and storage) technology industrial chain.
Chen, L +9 more
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, 2018 在实际工程中,常常需要利用模型去描述和分析问题。然而模型亦存在不确定性,即可能存在多个描述同一现象的模型,例如多个疲劳分析的模型。针对飞机结构的疲劳可靠性问题,提出在考虑三种裂纹扩展模型下基于贝叶斯公式的疲劳可靠度组合预测方法。针对不同应力水平下飞机结构试件的裂纹扩展数据建立了三种随机裂纹扩展模型;在考虑模型参数不确定性条件下,采用贝叶斯模型平均方法对三种模型进行组合;基于组合模型分析结构的可靠度。所提方法在分析飞机结构疲劳可靠度上,采用了组合模型,能够最大限度保障结果的稳定性。此外 ...
刘文杰, 袁修开
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FATIGUE CRACK GROWTH BEHAVIOR of 0Cr18Ni9 STAINLESS STEEL AT HIGH TEMPERATURES [PDF]
, 2012 研究奥氏体不锈钢0Cr18nI9在高温(550℃)下的疲劳裂纹扩展规律。测试采用标准CT(COMPACT TEnSIOn)试样,最大载荷范围为6.5 kn~14 kn,应力比为0.1(室温)和0.05(550℃)。裂纹扩展过程通过QuESTAr长焦距显微镜直接观测,同时采用COd(CrACk OPEnIng dISPlACEMEnT)规记录加载线位移。由于在高温条件下,测试终止时试样的裂纹前缘呈明显弧形,故此给出实测表面处裂纹长度有效值的修正方法。对高温疲劳裂纹扩展问题 ...
刘建中, 胡本润, 陈勃, 陈立杰
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, 2013 建立不同末端形状纳米纤维的黏附接触模型,主要分析了蘑菇状,铲状,柱状等不同末端形貌及蘑菇状纤维的几何参数对单纤维/基底黏附界面强度的影响,进一步分析了Y型纤维结构的黏附行为。进一步揭示一类生物的微观黏附机制提供了理论依据 ...
彭志龙, 陈少华
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Dianci bileiqi, 1987 用恒载荷双扭方法,在不同环境条件下,研究了电瓷材料亚临界裂纹的扩展,测得的KI-V曲线呈现出典型的三个区域:Ⅰ、Ⅱ、Ⅲ。第Ⅰ区域中的KI-V曲线未延伸到裂纹扩展速度小于10-6m/s的低应力区。低应力区的裂纹扩展随时间的增长而减速,直到停止。这种现象可用应力腐蚀极限和阻止裂纹扩展的非均质瓷的显微结构加以解释;根据测得的数据,本文还讨论了瓷材料的寿命预测,并把瓷的和钠钙硅酸盐玻璃的延期破坏作了比较。
M.Matsui, 谢清云
doaj
Numerical simulation of jointed rock mass blasting under different in-situ stress conditions [PDF]
, 2016 Two-hole blasting of jointed rock mass under different in-situ stress conditions(lateral pressure coefficient:0.5,1 and 2; vertical stress:5 MPa and 10 MPa) and joint angles(30°,45°,60° and 90°) was numerically simulated to study the ...
BAI Yu +3 more
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Study on energy dynamic change law in the process of water-contained coal caused by liquid nitrogen freezing [PDF]
, 2023 To study the energy dynamic change law of moisture-contained coal in the process of liquid nitrogen freezing, a self-developed acoustic emission (AE) experimental system for the whole process of liquid nitrogen frozen coal was utilized to analyze the ...
Botao LI +6 more
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Jianzhu Gangjiegou Jinzhan, 2023 设计制作了4个钢-SFRC组合桥面板试件，通过四点弯曲试验测试各试件的破坏模式、刚度、内力分布情况和延性等，研究配筋率、钢纤维体积率以及采用嵌入CFRP筋法加固对负弯矩区钢-SFRC组合桥面板抗弯性能的影响。结果表明：提高配筋率能够提高试件的刚度、开裂荷载和屈服荷载，但对极限荷载的影响较小；提高钢纤维体积率能够抑制裂纹的扩展并使试件的初始刚度提高8.5%左右；采用嵌入CFRP筋法加固能够有效减小截面应变，试件塑性能更充分地发展，加固试件均发生较明显的屈曲破坏 ...
朱宏平, 朱爱珠, 李正, 张朋
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