考虑结构自振周期约束的抗震结构的多目标多级优化设计

本文利用抗震结构的多目标多级优化设计理论，对考虑结构自振周期约束的抗震结构优化设计进行了研究，并根据规范ＧＢＪ１１－８９给出的四类场地的特征周期，计算了剪切型钢框架的算例。结果表明，在抗震结构优化设计中考虑结构自振周期约束有利于结构的抗震。     

板式建筑物楼梯对框架结构整体计算的影响分析

现行建筑物的结构设计一般不考虑楼梯参与框架结构的整体计算,但地震震害表明楼梯的破坏往往很严重．建立模型并利用SAP2000结构分析软件对不考虑楼梯作用及考虑楼梯作用的框架结构整体计算进行了比较分析,为楼梯抗震设计参与结构整体计算提供参考．     

单层球面网壳新型减震体系整体性能研究

选用60m跨度的空间k6型网壳考虑下部结构和不考虑下部结构两种计算模型进行动力时程分析,讨论两种模型在地震作用下抗震反应的差异,分析不同柱高度参数对网壳结构整体性能的影响,并对考虑下部结构模型布置4种约束屈曲支撑方案进行动力分析。结果表明,单层网壳下部结构的共同作用影响了网壳杆件受力变化规律,不同下部结构对网壳壳体的影响范围也相应变化;网壳下部结构柱高度对网壳结构整体刚度影响较大,柱越高网壳结构整体刚度削弱就越明显;约束屈曲支撑能够有效地控制网壳节点位移响应,效果明显,合理布置约束屈曲支撑有效吸收地震能量,减小网壳结构的地震响应。在考虑下部结构模型布置4种约束屈曲支撑方案中,方案2对主肋节点的水平和竖向位移均有较好的控制效果,主肋节点减震系数达到0.75。     

基于动力方法的RC框架结构整体超强能力分析

结构超强系数是结构在强震作用下不发生倒塌的重要因素,但是目前中国现行抗震规范没有纳入结构超强能力的影响,对于结构安全性的计算都是考虑结构构件,没有更多地考虑整体结构的承载能力.考虑不同设防烈度,不同层数严格按现行抗震规范设计了17个典型RC框架结构,采用OpenSees进行有限元建模与分析,并采用结构拟静力试验数据对有限元模型进行验证.采用非线性动力方法对所设计典型结构的地震反应进行了分析,得到了按现行抗震规范所设计结构的整体动力超强系数能力值的取值及其变化规律.结果表明:通过结构整体动力超强系数能力值,可以预测临界倒塌状态时结构的最大承载能力.分别按Ⅵ度,Ⅶ度和Ⅷ度抗震设防设计的结构,结构整体动力超强系数能力值分别至少要达到6,4和3,其最低值和NEHRP2000推荐条文中给出的结构整体超强系数限值3一致.     

带边框预制装配式剪力墙关键技术研究进展

预制装配式剪力墙结构是实现住宅产业化及建筑节能减排的重要途径.从国家住宅产业化的发展、预制剪力墙整体及构件受力性能、带边框剪力墙的抗震性能、钢筋和钢管灌浆套筒连接技术、考虑加载速率影响的剪力墙抗震研究五个方面对剪力墙的受力性能、破坏机理、变形能力等方面进行综述.通过分析指出,将边框(钢管混凝土、型钢等约束端柱)引入预制装配式剪力墙中可以有效改善传统单一的抗震防线,利用约束端柱和剪力墙形成多道防线提高结构整体抗震性能.因此,对带边框预制装配式剪力墙的承栽能力、变形性能、破坏模式等问题需要进行深入研究.     

钢骨建筑抗震评估与耗能减震构件简化模拟

本文以一座超高层钢骨建筑改建工程为例,进行抗震设计与性能评估案例介绍。其中进行三维结构非线性静、动力分析以检核其抗震性能。非线性动力分析结果显示：最大考虑地震作用下,梁端最大弯矩塑铰约达0.01rad、屈曲约束支撑最大核心段应变达1.25%、偏心斜撑连杆梁的最大剪力塑铰为0.065rad,皆未超过AISC抗震规范所订构件性能要求或实验所得其变形能力。其次介绍了此改建结构的计算模型、模拟方法、非线性分析所得结构整体与主要构件的性能表现,其中亦提出梁柱节点及偏心斜撑构架剪力连杆梁等构件加固前后的简化模拟方法,并利用梁柱节点加固试验结果加以比较验证。     

抗震设防地区多层砌体房屋的抗震设计

砌体结构作为我国传统的建筑形式,仍在我国各类建筑中占有十分重要的位置。砌体结构的抗震设计进展也始终为结构工程师所关注。结合新抗震设计规范,介绍了约束砌体中构造柱间距的设置原则及其抗震承载力的计算;各种砌体结构抗震措施的基本要求等。     

抗震设防地区多层砌体房屋的抗震设计

砌体结构作为我国传统的建筑形式,仍在我国各类建筑中占有十分重要的位置。砌体结构的抗震设计进展也始终为结构工程师所关注。结合新抗震设计规范,介绍了约束砌体中构造柱间距的设置原则及其抗震承载力的计算;各种砌体结构抗震措施的基本要求等。     

大型异形体组合结构抗震性能

为研究由不同材料构成的大型异性体组合结构的抗震性能,采用通用有限元分析及设计软件MIDAS/Gen对底部为规则混凝土框架结构、上部为圆柱形闭合钢架结构的组合结构建立了分析模型,采用组阻尼考虑不同材料阻尼比的影响,对整体结构进行抗震反应谱分析,计算水平地震作用下结构的位移与受力情况.研究结果表明:不同的结构类型会使组合结构产生较大变形,应采取有效措施;不同材料组成的组合结构,应考虑组阻尼对结构的影响.     

对竖向非规则框架设计的思考

结合工程设计实践,分析单榀钢筋混凝土竖向非规则框架的受力机理：传力路线长,受力构件多;刚度变化：水平刚度沿着高度方向有突变,应力集中现象严重;变形特点：各柱的竖向变形差异较大,必须考虑对结构整体内力的计算影响;抗震设防要求：采用强柱弱梁设计,形成延性结构。通过与规则框架的比较,提出竖向非规则框架属于抗震不利的结构形式,实际问题的处理应从结构布置、内力与配筋计算、构造措施等方面加以综合考虑。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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