框排架厂房空间结构地震反应分析

一端设置山墙的框排架厂房在地震作用下将出现扭转振动，不考虑这种影响对结构设计来说是偏于不安全的。本文用于空间计算模型分析了框排架结构的地震反应，并与平面结构计算结果进行了比较。结果表明该类结构的空间作用调整系数较大。     

基于PUSH—OVER方法的厂房弹塑性分析

结构抗震理论中通过弹性分析方法无法确切的掌握结构在大震下进入塑性后的真实反应，特别是对于复杂的不规则结构，如果存在薄弱部位可能会在地震作用下首先进入塑性阶段，大量吸收地震能量并导致破坏，还可能因为局部破坏而造成结构的整体倒塌。随着结构理论以及计算软件的日益完善，在此基础上形成的Pushover分析方法逐渐得到广泛应用。本文介绍了Pushover分析的基本原理和实施Pushover分析的关键步骤，运用Midas软件对某单层厂房进行了Pushover分析实例，对一般单层厂房结构罕遇地震作用下的抗震性能做出合理的评价。     

日本神户市建筑结构震害特征分析

本文采用冲量原理计算竖向地震作用，并考虑与水平地震共同作用，对日本神户市建筑结构震害特征进行了分析，供抗震设计时参考。     

高层建筑结构刚度退化与地震作用响应关系的理论分析

弹塑性分析方法是基于性能抗震设计的重要手段，由于影响该计算结果的因素较多，对分析结果可靠性的合理评判至关重要。从理论角度给出了高层建筑结构在地震作用下刚度退化系数和弹塑性耗能附加阻尼的定量关系，在此基础上推导了结构的内力响应和位移响应随刚度退化而发生变化的计算式，并分析了结构自振周期、初始阻尼比及场地特征周期等参数的影响规律。同时讨论了内力响应与位移响应趋势不一致以及弹塑性分析的基底剪力响应大于相应弹性结果等两类不满足基本规律的特殊问题。最后，通过对一个实际工程进行罕遇地震作用下的弹性与弹塑性时程分析，得到基底剪力和位移的响应，同时运用本文推导的理论计算式进行计算，结果显示，计算结果与有限元分析结果基本吻合。研究成果可为基于性能抗震设计以及弹塑性时程分析的结果评判提供参考。     

张弦网壳结构地震响应规律分析

对张弦网壳结构地震响应规律进行大量理论分析与计算研究。在建立多自由度体系计算模型及地震响应基本方程的基础上,探讨对比采用不同计算方法、不同方向单维地震作用及多维地震作用下张弦网壳结构的地震响应,深入地研究张弦网壳屋盖与下部支承体系的静力及动力相互作用,强调采用整体模型的必要性,并给出张弦网壳结构地震响应的特点与规律,从而对张弦网壳结构的抗震设计提出有益的建议。     

地震作用下不对称高层建筑平移-扭转耦联振动的控制研究

本文分析了不对称高层建筑平移—扭转耦连振动的动力特性及其地震作用下的动力反应，根据结构控制的基本理论提出了不对称高层建筑LTTMD控制的计算理论及计算方法，编制了相应的计算机程序。并用实例分析了一个20层不对称高层建筑；其结果表明，施加LTTMD控制机构后，结构的水平及扭转地震反应均显著降低。     

高烈度地区某框架结构的隔震分析与设计

传统高烈度区框架结构设计,需要通过加大构件截面尺寸以提高结构刚度来抵抗地震作用,本文采用隔震技术对某高烈度区框架结构进行计算分析,通过在基础与上部结构之间设置铅芯橡胶支座和普通橡胶支座,采用ETABS计算软件对非隔震结构和隔震结构进行设防地震和罕遇地震作用下的时程分析,隔震后上部结构的水平地震作用效应明显降低,在设防地...     

基于精确柔度矩阵的多肢剪内墙－框架体系的抗震分析

本文在框架剪力墙精确侧移公式的基础上建立结构的柔度矩阵，确定结构的自振周期和振型，按照实际的地震作用分布计算结构的作用效应和进行抗震分析。最后通过计算实例对本文方法和一些常用方法的结果进行分析和讨论。     

索穹顶结构地震作用计算方法的对比分析

由于结构的几何非线性，我国GB 50011—2010《建筑抗震设计规范》中并未对以索穹顶为代表的柔性大跨屋盖结构的地震作用计算方法作出明确规定。为此，以重力荷载代表值作用下的平衡构型为考察对象，通过与时程分析法计算结果进行对比，考察振型分解反应谱法用于索穹顶结构地震作用计算的适用性。为保证地震动输入的一致性，时程分析时使用由设计反应谱生成的人工地震波。基于振型参与质量系数，提出了一种判别屋盖索穹顶结构地震作用主要贡献振型的指标，并指出应采用对屋盖索穹顶结构的地震作用提供主要贡献的振型确定瑞利阻尼系数，否则时程分析时将显著高估结构阻尼效应并造成结构地震响应的计算结果偏小。采用两种方法计算索穹顶结构在不同挠跨比限值(预应力水平)下的多遇地震响应。结果表明，对于满足非抗震设计验算的Geiger型和Levy型索穹顶算例，振型分解反应谱法计算得到的结构地震响应与时程分析法的结果匹配良好，验证了该方法进行此类柔性屋盖结构地震作用计算的适用性。     

上海电影博物馆主楼超限高层结构设计

上海电影博物馆主楼采用框架-剪力墙结构，在5层通过钢结构连廊与电影艺术研究所相连。该工程为平面和竖向均特别不规则的超限高层建筑，从概念设计着手，合理布置竖向抗侧构件，针对不同的超限情况采取了相应的技术措施。采用SAT-WE、PMSAP程序对结构进行多遇地震作用下的计算，各项计算指标均满足规范要求。对结构进行了弹性动力时程分析补充计算和罕遇地震作用下静力弹塑性分析，计算表明，结构能够抵抗大震水准的地震作用，钢结构连廊滑动支座的设计满足连廊罕遇地震作用下的位移要求。     

不同钢—混凝土组合剪力墙抗震性能对比分析

钢—混凝土组合剪力墙中钢板的布置形式是影响其抗震性能的一个主要因素。通过对两组内置钢板混凝土组合剪力墙和内藏钢桁架混凝土组合剪力墙试验的模拟,确定计算模型的建立方法,并选取两片相同含钢率的内置钢板混凝土组合剪力墙和内藏钢桁架混凝土组合剪力墙进行在侧向低周反复荷载作用下的计算分析,对比了两片剪力墙的承载力、刚度及其退化过程、延性、耗能特性及滞回特性。研究结果表明:在相同含钢率的条件下,内藏钢桁架混凝土组合剪力墙与内置钢板混凝土组合剪力墙相比,承载力、延性、耗能能力均有较明显提高。     

Traditional Urbanism Meets Residential Affluence: An Analysis of the Variability of Suburban Preference

This article evaluates the likelihood that wealthy suburban residents in the U.S. would endorse the ideas currently being promulgated by advocates of traditional urbanism. The results of an attitudinal survey of 185 affluent, mostly White residents of a suburb 25 miles north of Dallas, Texas, are reported. Four hypotheses were developed and used to assess what aspects of residential preference may be linked to an acceptance of traditional urban-ism concepts. The findings indicate that residents are very attached to their neighborhood and are unlikely to accept criticisms of their suburban lifestyle. Further, agreement with traditional urbanism concepts was associated with a perceived failure of the physical planning aspects of suburban development such as access to services. The conclusion is that in general, affluent suburban residents are likely to base any disfavor with suburban living on factors that affect them in very practical ways and not on a lack of community sentiment or a sense of the social or environmental weaknesses of suburban development. The findings also support the view that residential preferences are not inflexible and are sometimes even contradictory. This adaptability suggests that education about the impacts of development may be warranted.     

Review of explosion and fire hazard of liquefied petroleum gas

The properties of LPG that contribute to its fire and explosion hazards are outlined. The hazards include those associated with small vapour leaks from appliances and gas cylinders as well as major hazards associated with loss of containment and rapid vaporisation of tonnage quantities of the liquefied gas. Estimates are given of the magnitude of effects that might follow the latter type of release. In the UK the record of LPG is poor with regard to general fire occurrence compared with that of natural gas or town gas. This performance will need to be improved if the quantity of LPG used is to be increased. These improvements might be achieved by developing its use as a piped fuel and in motor vehicles, but both these would require careful hazard analysis. Although the record for major hazard with LPG in the UK is good, quantitative studies indicate that handling and transportation of tonnage quantities by road and sea are not safe enough. Methods are suggested for reducting the risk.     

Spatial concentration of manufacturing firms in China

Applying the methodology developed by Duranton and Overman, we analyse localization and dispersion of firms in China. Using a unique and detailed dataset on manufacturing firms in China, we are able to follow the changes in location patterns of firms between 2002 and 2008. Our analysis shows that firms in China are more localized than in the UK or Japan. Localization is comparable to that in the US, and takes place at relatively small scales that are consistent with the size of Chinese cities. Localization increases rapidly, even in the relative short period between 2002 and 2008, especially new entrants localize. Private firms, firms from Hong‐Kong, Macao and Taiwan, and foreign firms are more localized than state‐owned firms. Our findings are consistent with the notion that China is increasingly liberalizing its economy, enabling (profit seeking) manufacturing firms to benefit from agglomeration economies.     

Development of a biological filtration model applied for advanced treatment of sewage

A mathematical model of biological filtration process is developed in this paper. A biological filtration process has advantages that filtration action and biological activities are combined in a single reactor with aid of filter media. Both physical and biological functions are incorporated in this developed model to simulate both mechanisms. Backwashing is expressed by the assumption that a mean captured solids concentration is input as data, and a captured solids concentration is kept at that value during each filtration run. The developed model is applied to explain the experimental performance with biological filtration reactors, in which batch cultivation of autotrophic bacteria and continuous treatment of actual sewage are carried out. Its applicability is discussed by comparing the simulated results with the experimental data. This model can favourably estimate maximum accumulation of autotrophic bacteria on the medium in batch cultivation, long-term treatment performance in continuous treatment, details of water quality profiles through the filter bed, and biomass. Required hydraulic retention time for nitrification and an appropriate recirculation ratio in a winter season are discussed with this model. This model predicts that a HRT of 1.1 h or above is required to achieve nitrification with remaining NH4(+)-N of less than 1 mgN/L and that an appropriate recirculation ratio is 2-3.     

浅谈既有住区海绵化改造中的植物选择与应用

在全国海绵城市建设和老旧小区改造大面积开展的形势下,针对既有住区现状特点进行海绵化改造,从植物在海绵建设中发挥重要生态和景观作用的角度出发,探讨如何进行植物应用和选择。首先按照项目所在地气候区进行植物品种选择,使植物生长状态最优;其次选择习性与不同海绵设施特点相匹配的植物,提高水资源的利用和经济效益;最后根据不同场所的特点选择形态特征与之匹配的植物进行搭配,营造出和场地氛围融合的植物景观。通过以上三个步骤逐一筛选,得出适用于既有住区各海绵项目的植物品种及搭配模式,帮助设计者在受限的种植条件下,形成体现地域特色、适宜场地特征且高效低维护的海绵植物景观。     

试谈文物建筑保护抢救的重要性和紧迫性

通过对我国当代经济的发展促进了城市现代化步伐的加快,城市内的文物建筑是随着城市的发展而被保护或被毁灭现状的分析认识,提出了保护的“质”和“量”是随着城市发展深度的不同而异,文物建筑是在发展中求保护的观点,针对文物建筑的保护与抢救这一亟待解决的历史性问题,总结了文物建筑保护与抢救的一系列方法及原则。     

The future of work

The author argues that the structure of employment in Britain is changing for good. The days of jobs for life with 30 years in the same company and a gold watch at the end of it are over. He describes how, instead, managers are having to cope with changing work patterns and, chameleon-like, are having to adjust with the times in order to survive     

热水间歇供暖加热过程数理模型

将建筑物供暖过程模拟划分为两个串联工作的热力系统，在假设条件下建立间歇供暖加热过程微分方程组及其关系式，并通过初步的实验加以验证，结果表明假设条件基本符合实际，误差能满足工程需要。     

滤纸法在现场基质吸力量测中的应用

介绍滤纸法现场测量基质吸力的装置和测量结果,并与张力计测量结果、水土特征曲线算得的结果相比较,说明研制的装置简单实用。还介绍了双圈牌滤纸的率定过程和率定曲线,探讨了一些对测量精度有影响的因素。