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Jianzhu Gangjiegou Jinzhan, 2015 大量工程实践表明,组合梁的破坏主要源于抗剪栓钉的疲劳破坏。在疲劳荷载下,承受拉压循环应力的栓钉裂纹萌生、扩展至最终断裂,使钢梁与混凝土的组合作用失效,所以研究栓钉中裂纹萌生及扩展规律对实际工程具有重大意义。扩展有限元(eXtended Finite Element Method,XFEM)是近年来发展起来的一种求解涉及移动非连续问题的有效方法。基于ABAQUS平台利用此方法建立了组合梁推出试验的模型,进行了静力承载力以及疲劳寿命分析,模拟了栓钉中裂纹从萌生到断裂失效的过程 ...
韩庆华, 王一泓, 徐杰, 邢颖
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Jianzhu Gangjiegou Jinzhan, 2011 本文提出了一个模拟组合梁栓钉受力性能的有限元模型,该模型采用8节点实体单元来模拟混凝土楼板、钢梁与栓钉,压型钢板则采用8节点双曲度壳单元来模拟。该模型充分考虑了荷载及边界约束情况,并假设压型钢板与混凝土楼板之间无相对滑移。本文应用该模型对一系列栓钉推出试验进行了模拟分析,结果表明该有限元模型能精确地模拟组合梁中栓钉的受力性能。此外,本文还研究了无侧向支撑试件在推出试验中的非成熟破坏问题,解释了破坏机理,提出了有效防止方法。
王隽
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Jianzhu Gangjiegou Jinzhan在北方寒冷地区，钢管混凝土结构受冻融作用侵蚀，造成钢管开裂以及钢管混凝土结构力学性能劣化导致结构破坏事故时有发生。针对冻融侵蚀后钢管混凝土界面黏结性能的问题，制作钢管混凝土推出试件，考虑冻融循环、混凝土强度、钢管径厚比等不同参数，进行冻融试验和推出试验，分析了界面黏结力的分布规律和影响因素，研究了冻融循环作用后钢管混凝土界面黏结滑移本构关系，确定平均黏结强度以及峰值黏结强度、残余黏结强度特征值。结果表明，随着冻融循环次数的增加，界面平均黏结强度减小，极限荷载对应的滑移逐渐增大，而残余黏结强度线性减小 ...
曾在平 +3 more
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Jianzhu Gangjiegou Jinzhan, 2018 钢-混凝土组合梁广泛应用于各类建筑与桥梁等结构,为适应装配式组合结构的发展需求,提出了一种将带预制圆孔的混凝土板与焊接栓钉的钢梁安装定位后在预制孔内后填高强填料以固定栓钉连接件的预制装配式钢-混凝土组合梁。通过静力推出试验,研究栓钉直径、预留孔成孔方式与孔径比(预留孔径和栓钉直径比值)对预制装配式组合梁栓钉抗剪连接件的破坏形态、抗剪承载力和滑移性能的影响规律,并进行了普通现浇组合梁栓钉抗剪连接件的对比试验。试验结果表明:破坏形态均为栓钉剪断和混凝土板开裂 ...
钟琼, 霍静思, 王海涛, 陈俊
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Jianzhu Gangjiegou Jinzhan, 2006 进行了20个型钢混凝土构件的推出试验、20根型钢混凝土偏心受压柱试验,以及23根型钢高强混凝土柱在反复荷载作用下的试验。通过在型钢与混凝土之间埋设的电子滑移传感器和电阻应变片,得到了粘结应力和内部滑移沿型钢埋置长度的分布规律;考虑了混凝土强度、型钢的保护层厚度和埋置长度,以及横向配箍率等诸因素,建立了型钢混凝土粘结强度的计算公式;分析了构件长细比、荷载偏心距对粘结强度和滑移应变的影响,提出了偏心受压柱粘结滑移本构关系的一般表达式;研究了型钢高强混凝土柱在动力作用下粘结滑移的分布规律和粘结退化机理 ...
薛建阳 +4 more
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Veterinary Dermatology, Volume 34, Issue 6, Page 543-553, December 2023., 2023 Background – Hymenoptera envenomation with honey bee (Apis mellifera) and paper wasp (Polistes spp.) may cause life‐threatening anaphylaxis in dogs. In human patients, clinical history, intradermal testing (IDT) and measurement of allergen‐specific serological immunoglobulin (Ig)E (sIgE) are used to support a diagnosis of Hymenoptera venom ...
Hilary H. Chan +3 more
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Region‐wide retreats from lower elevations of range‐restricted birds across the Northern Andes
Conservation Biology, Volume 37, Issue 5, October 2023., 2023 Abstract Local studies show upslope shifts in the distribution of tropical birds in response to warming temperatures. Unanswered is whether these upward shifts occur regionally across many species. We considered a nearly 2000‐km length of the Northern Andes, where deforestation, temperature, and extreme weather events have increased during the past ...
Wilderson Medina +2 more
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Family Process, Volume 62, Issue 2, Page 534-556, June 2023., 2023 Abstract Study of change mechanisms is important to advance theory development and to reveal the active components that make a critical difference in treatment. Improved outcomes in a randomized controlled trial that favored Congruence Couple Therapy (CCT) vs individual‐based Treatment‐as‐Usual (TAU) were correlated within each group.
Bonnie K. Lee +2 more
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Infant Mental Health Journal: Infancy and Early Childhood, Volume 44, Issue 2, Page 200-217, March 2023., 2023 Abstract Parenting interventions can improve parenting outcomes, with widespread implications for children's developmental trajectories. Relational savoring (RS) is a brief attachment‐based intervention with high potential for dissemination. Here we examine data from a recent intervention trial in order to isolate the mechanisms by which savoring ...
Jessica L. Borelli +5 more
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Journal of Traumatic Stress, Volume 36, Issue 1, Page 59-70, February 2023., 2023 Abstract Clinical supervision is critical for the uptake of psychotherapy but difficult to facilitate in countries with limited providers, resources, and internet infrastructure. Innovative supervision approaches are needed to increase access to mental health treatments in low‐to‐middle income countries (LMICs).
Alexandra B. Klein +16 more
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