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Torsionally coupled dynamic performance analysis of asymmetric offshore platforms subjected to wave and earthquake loadings

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Earthquake Engineering and Engineering Vibration 2010年第2期9卷 247-258页

作者： He Xiaoyu and Li Hongnan 1.zhejiang provincial Planning,design & research institute of Communications,Hangzhou 310006,China 2.State Key Laboratory of Coastal and Offshore Engineering,Dalian University of Technology,Dalian 116024,China zhejiang provincial Planning Design &amp research institute of Communications Hangzhou 310006 China

The dynamic equations of motion of asymmetric offshore platforms under three different environmental conditions:seismic action,wave action and their combination are established in this paper. In establishing these motion equations,three typical eccentricity types including mass eccentricity,rigidity eccentricity and their combination were considered,as are eccentricities that occur un-idirectionally and bi-directionally. The effects of the eccentricity type,the dynamic characteristics and the environmental conditions on the torsional coupling response of platforms are investigated and compared. An effort has also been made to analyze the inffluence of accidental eccentricity on asymmetric platforms with different eccentricity in two horizontally orthogonal directions. The results are given in terms of non-dimensional parameters,accounting for the uncoupled torsional to lateral frequency ratio. Numerical results reveal that the eccentricity type has a great inffluence on the torsionally coupled response under different environmental conditions. Therefore,it is necessary to consider the combination of earthquake and wave action in the seismic response analysis of some offshore platforms.

关键词： offshore platform asymmetric structure accidental eccentricity torsion coupling earthquake load wave load

8度地震区高层建筑短肢剪力墙结构的判别及设计探讨

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土木工程学报 2011年第9期44卷 65-70页

作者：张举涛甘肃省建筑设计研究院甘肃兰州730030

《高层建筑混凝土结构技术规程(》JGJ 3—2002)对短肢剪力墙较多的剪力墙结构未给出明确的判定方法,在使用中引起了一定的困惑。为此介绍几种文献对高层建筑短肢剪力墙结构的判别方法,各法不尽相同,差异也比较大。讨论短肢剪力墙及短肢... 详细信息

《高层建筑混凝土结构技术规程(》JGJ 3—2002)对短肢剪力墙较多的剪力墙结构未给出明确的判定方法,在使用中引起了一定的困惑。为此介绍几种文献对高层建筑短肢剪力墙结构的判别方法,各法不尽相同,差异也比较大。讨论短肢剪力墙及短肢剪力墙结构的判别问题。取用8度地震区的一个工程实例,设定不同高度、不同底部地震倾覆力矩比共6种模型,进行短肢剪力墙结构和一般剪力墙结构的分析比较,发现当房屋高度分别不高于60m、80m1、00m时,短肢剪力墙承担的底部地震倾覆力矩分别大于40%、30%、20%时,将该结构判定为短肢剪力墙较多的剪力墙结构,基本能与大部分文献吻合,建议高层建筑按不同高度用不同的底部地震倾覆力矩比判别是否属于短肢剪力墙结构,并提出在短肢剪力墙结构设计中应注意的一些问题。

关键词：高层建筑短肢剪力墙短肢剪力墙结构判别

INVESTIGATION　OF　ACTIVE　CONTROL　FOR　DYNAMIC　STABILITY　OF　HELICOPTER　ROTOR－BODY　COUPLING

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Chinese Journal of Aeronautics 1996年第4期9卷 269-272页

作者： Ling Aimin(Chinese Helicopter research and design institute,Jindezhn, Jiangxi, China, 333001) Chinese Helicopter Res. Des. Inst. Jindezhen Jiangxi 333001 China

A study is conducted on the feasibility of helicopter ground and air resonanceby using actively controlled tabs mounted at the trailing edge of an aerofoil. A method isdeveloped to obtain the optimal feedback control law through constructing a referencemodel according to requirements of stability levels in the modal space. The effects of rotorspeed and length and location of tabs on the control law are analyzed, and it is found possible that a controller can be designed into constant feedback gain against rotor speed andto feed back only to the dominant system states to eliminate the unstable range of rotorspeed.

关键词： tabs (control surfaces) helicopters rotor body interactions coupling dynamic stability active control

Dynamic Analysis of a Single-Column Platform

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China Ocean Engineering 1991年第4期6卷 385-394页

作者： Lian Gan , Ni Kan, Hu Kai and Guo Dawei Prof., Senior Engineer, Marine design and research institute of China, Shanghai Senior Engineer, Marine design and research institute of China, Shanghai Engineer, Marine design and research institute of China, Shanghai

In this paper, a single-column structure used as well-head platform is studied. The loads of wave and current exerted on the single-column will be greatly reduced, therefore the cost of the structure will be decreased. The advantages of the single-column structure compared with ordinary jacket structure are explained. A dynamic analysis of this type of structure is made and some problems related to dynamic analysis are solved. In order to check the reliability of computation theory and programme, model tests have been carried out. However, as space is limited, the conclusion of tests will be introduced in another paper. Therefore, this type of structure is applicable for proctical engineering.

关键词： single-column structure dynamic analysis diffraction wave theory natural period,resonant dynamic strength damping ratio fictitious stiffness of pile top fatigue analysis

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青城山房,成都,四川,中国

世界建筑 2008年第2期 82-87页

作者： Beijing institute of architectural design 北京市建筑设计研究院

当青城山房项目在世界文化遗产，国家5A级风景区青城山脚下渐渐呈现的时候，所有的人都舒了口气。这一组建筑群落没有成为国家级风景区的累赘，反而成为左邻右舍诸多房地产项目中的典范。这是因为建筑群的形体、密度、尺度、选材、质感... 详细信息

当青城山房项目在世界文化遗产，国家5A级风景区青城山脚下渐渐呈现的时候，所有的人都舒了口气。这一组建筑群落没有成为国家级风景区的累赘，反而成为左邻右舍诸多房地产项目中的典范。这是因为建筑群的形体、密度、尺度、选材、质感、与山体树木丛林有机相融，以一种低调内敛的精致，回应着世界文化遗产的人杰地灵，并将当代人的居住行为空间梳理得流畅而舒适。

关键词：青城山世界文化遗产成都四川中国建筑群落房地产项目行为空间

Preparation and characterization of nitrogen-doped titanium dioxides

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Science China Chemistry 2007年第2期50卷 212-216页

作者： ZHU GuoPing1 & ZHOU KangGen2 1 Environmental Science research & design institute of zhejiang province,Hangzhou 310007,China 2 Department of Environmental Engineering,School of Metallurgical Science and Engineering,Central South University,Changsha 410083,China 1. Environmental Science research & design institute of zhejiang province Hangzhou 310007 China 2. Department of Environmental Engineering School of Metallurgical Science and Engineering Central South University Changsha 410083 China

A type of high visible-light active titanium oxinitride(TiO2-xNx) powder was prepared by a simple proc-ess:the calcination of the hydrated titanium dioxide at the atmosphere of ammonia-argon using a tu-bular electric furnace at high temperatures. The hydrated titanium dioxide was synthesized as the precursor of TiO2-xNx using titanic acid as raw material,which came from sulfate technique of produc-ing titanium white. The effects of temperature and reaction time on the nitrogen content,grain size and crystal structure were studied. The visible-light activity and photocatalysis capability of the powder were also investigated.

关键词： nitrogen-doped titanium dioxides visible-light activity photocatalysis titanium oxinitride

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景德镇陶溪川大剧院

建筑学报 2023年第4期 56-60页

作者： David Chipperfield Architects institute of Shanghai architectural design ＆ research Co. ltd 戴卫·奇普菲尔德建筑事务所上海建筑设计研究院有限公司

A METHOD FOR PREDICTION OF SHALLOW WATER TIDES

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Journal of Oceanology and Limnology 1984年第1期2卷 34-48页

作者： Xu Hanxing (Shu Han-shing) (The design and research institute of the Shanghai Waterway Bureau, Shanghai) 1. The design and research institute of the Shanghai Waterway Bureau Shanghai

This paper describes a new approach to tidal prediction, gives a brief description of harmonic analysis method and introduces a tidal height model adopted recently by Shanghai Port. It is expected that this method will be valid for ports similar to Shanghai. Based on the tidal behavior in the shallow water area, significant tidal constituents have been selected in line with local conditions to form a model of tidal height computation, and the required span of data analysis was defined, resulting in a two-fold increase of the prediction accuracy. For non-periodical water level fluctuation a "Weather Chart Predicting Method" has been adopted, which is simple in operation and produces comparatively good result. Based on the combination of the methods of analysis and prediction computation for periodical and non-periodical water level fluctuation, a one-day short-term tidal prediction is issued for navigation of ships serving the Shanghai Port, for flood-control, and for other purposes. The long-term predic

关键词： A METHOD FOR PREDICTION OF SHALLOW WATER TIDES

Dynamic Analysis of a Single-Column Platform (II)

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China Ocean Engineering 1992年第4期7卷 395-402页

作者： Lian Gan, Ni Kan, Hu Kai Guo Dawei 2. Professor, Senior Engineer, Marine design & research institute of China, Shanghai3. Senior Engineer, Marine design & research institute of China, Shanghai4. Engineer, Marine design & research institute of China, Shanghai

This paper describes the study of a single-column structure used as well-head platform. In order to check the reliability of computation theory and programme, model tests have been carried out. The paper introduces th... 详细信息

关键词： single-column structure dynamic analysis diffraction wave theory natural period damping ratio