Results 41 to 50 of about 1,744 (160)

残余应力对冷弯厚壁方矩管轴压承载力的影响

open access: yesJianzhu Gangjiegou Jinzhan, 2017
根据已有残余应力分布模型对冷弯厚壁型钢典型截面进行了理论分析,得到残余应力对冷弯厚壁型钢轴压构件承载力的影响规律。在理论分析的基础上对不同厚度、不同宽厚比的Q235、Q345冷弯厚壁型钢进行有限元分析,得到不同长细比的各构件在考虑和不考虑残余应力两种情况下的轴压承载力,并研究残余应力对冷弯厚壁型钢长柱轴压承载力的影响。结果表明:残余应力对冷弯厚壁型钢轴压承载力的影响在长细比为90时达到最大,且对Q235钢的影响比Q345钢的影响略小 ...
李元齐, 李功文, 沈祖炎
doaj  

The earthquake sequence, surface rupture characteristics and engineering effects of the MS6.9 Qinghai Menyuan earthquake on January 8, 2022 [PDF]

open access: yes
At 01:45 on January 8, 2022, an MS6.9 earthquake occurred in Menyuan County, Haibei Tibetan Autonomous Prefecture, Qinghai Province. In order to gain a deeper understanding of the activity characteristics of this earthquake, the author conducted a ...
Beilei Zhan   +4 more
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窄翼缘PEC中长柱轴压整体稳定性能试验研究

open access: yesJianzhu Gangjiegou Jinzhan, 2023
为研究窄翼缘PEC中长柱轴压整体稳定性能,设计制作9根组合长细比介于76~141(正则化长细比介于0.84~1.55)的窄翼缘PEC中长柱,进行轴压整体稳定性能试验。研究窄翼缘PEC中长柱的初始弯曲、长细比、混凝土强度等因素对其破坏模式和轴压整体稳定承载力的影响。试验结果表明,窄翼缘PEC中长柱在轴压荷载下的破坏模式表现为绕弱轴的弯曲失稳,长细比和初始弯曲显著影响试件的破坏模式和极限承载力。当试件的正则化长细比大于1.0,初始弯曲大于L/1 000时,试件的破坏模式表现为整体极值点失稳 ...
张文轩   +5 more
doaj  

借“鸟”为名的探讨——评述电影《BIRDY》与话剧《鸟人》 [PDF]

open access: yes, 2014
电影《bIrdy》和话剧《鸟人》这两部作品,跨越时间、地域以及艺术形式,均选择以“鸟“为中心意象,并通过对鸟人的刻画,以小见大地探讨了现代人在身份认同上所遭遇的焦虑,并且都形成了忧郁的艺术氛围 ...
周尚谊
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The Timber Arch Lounge Bridges in Fujian and Zhejiang Provinces [PDF]

open access: yes, 2009
木拱桥是指由木杆构件纵横相贯形成的拱状木桥,因其形如虹,俗称虹桥。本文分析了现存的闽浙木拱廊桥与宋代汴河虹桥的结构差异,并比较其他形式的木拱结构,探讨了闽浙木拱廊桥的施工程序。There is a timber arch bridge,consisted of two groups of lengthwise components that were placed alternately,namely Hongqiao,or Rainbow Bridge.This article analyses ...
曹春平
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Wooden Arch Bridges of Fujian and Zhejiang [PDF]

open access: yes, 2009
现存的闽浙木拱桥与宋代的汴河虹桥存在着结构上的相似性,但其技术经过很大的改进,流传范围广,延续时间长,适应性较强,表明其体系相对独立,可能有着自己的发展脉络。Existing wooden arch bridges of Fujian and Zhejiang are similar to the Hong Bridge on the Bian River of the Song Dynasty in structure.However,technology of the wooden arch ...
曹春平
core  

Influence of ultra-close undercrossing shield on deformation of existing tunnels [PDF]

open access: yes
With continuous development of urban construction in recent years, many Chinese cities have successively developed and increased the construction of urban rail transit projects, and the construction of the metro engineering causes surrounding surface ...
DAI Zhengbin1, 2 , LU Yunlong1, 2
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冷弯薄壁型钢构件的直接强度设计法

open access: yesJianzhu Gangjiegou Jinzhan, 2003
受压或受弯的冷弯薄壁卷边槽钢有板件局部屈曲,截面畸变屈曲和整体弯曲屈曲或弯扭屈曲三种模式。本文着重介绍板件的相关屈曲和计算截面畸变屈曲应力的方法并阐述了三种屈曲模式之间的相关关系。指出用传统的有效截面设计法计算受压和受弯冷弯薄壁卷边槽钢承载力的弊端,较详细地说明了用构件全截面计算的直接强度设计法。
陈骥
doaj  

单轴对称截面轴压构件弯扭失稳换算长细比的一般计算式

open access: yesJianzhu Gangjiegou Jinzhan
单轴对称截面轴压构件弯扭失稳的换算长细比是计算其极限荷载的重要参数。从单轴对称截面轴压构件弯扭失稳的平衡微分方程入手,采用Galerkin法推导了4种边界约束条件的弯扭失稳临界荷载的一元二次方程,并进一步得到了基于荷载比、基于双长细比的弯扭失稳换算长细比的理论公式。基于理论公式,分别对比了我国现行标准GB 50017-2017中双角钢T形截面轴压构件扭转失稳、弯扭失稳的换算长细比,揭示了其中存在的问题。进而基于理论公式,提出了新的双角钢T形截面轴压构件扭转失稳、弯扭失稳的换算长细比 ...
刘占科   +4 more
doaj   +2 more sources

Research on the Dynamic Intelligent Quality Control of Cold Rolling Mill Process [PDF]

open access: yes, 2007
针对带钢冷连轧过程质量控制特点,论文提出了一种基于模糊逻辑推理和神经网络的动态智能质量控制器DIQC。论文的最初动机是希望寻找一种有效的控制方法,来解决复杂的、非线性的、系统间存在强交互作用的、时变的带钢冷连轧系统控制问题。这类过程往往受干扰与噪声的影响,具有很强的不确定性。对于带钢冷连轧系统,需要增加控制器的智能性,以提高控制器从过程中抽象出函数关系的能力,并且通过调整这些关系以提高系统的控制精度,也即提高控制器的学习与推理能力。论文的目的就是针对上述问题,综合运用模糊逻辑推理和神经网络方法 ...
程菲
core  

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