砌体结构裂缝的控制措施

1设计方面（1）建筑物的屋面及外围护结构应采用符合热工要求和节能标准的保温措施。 （2）建筑物的平面形状应规则，避免平面形状突变。当平面有凹口时，凹口周边楼板的配筋应适当加强；当楼板平面形状不规则时，应调整平面或采取构造措施。     

浦东展讯二期超限高层抗震设计

高层建筑平面布置图中因为电梯间、楼梯间、中庭等楼板开洞空间的设置,往往都属于规范规定的平面不规则建筑,都需要对结构进行进一步的抗震性能分析。展讯二期二层大堂上空造成楼板尺寸和平面刚度急剧变化,有效楼板宽度小于该层楼板典型宽度的40%,属于现行规范规定的平面不规则的超限高层建筑工程。采用两种程序对结构抗震性能进行分析,并加强该层及相邻层楼板抗震构造措施。同时二层楼板计算时按照全层弹性膜单元模拟开洞真实刚度,复核墙柱及楼板配筋。     

运用PKPM分析竖向荷载作用下不规则无梁楼板

运用PKPM结构分析软件,分析比较了在相同竖向荷载作用下L形不规则无梁楼板不规则边形状及尺寸的变化对板内力影响及阴阳角应力集中现象,得出L形不规则板的存在没有改变整个无梁楼板结构体系的受力特点的结论。     

某大型商业综合体结构设计

本工程为超长结构,水平向最大长度达226 m,未设缝,补充了温度应力计算,并采取其它构造措施控制楼板裂缝.平面存在凹凸不规则和楼板局部不连续,补充中震弹性计算,并根据计算结果,对楼板连接薄弱处予以加强.对于扭转不规则,则利用楼梯间设置型钢混凝土斜撑控制建筑物的扭转.对于下沉广场处一层楼板大开洞,采用嵌固在地下室顶板和嵌固在地下一层楼板模型包络设计配筋.     

某平面异形的隔震结构抗震分析

云南某中学结构平面凹凸不规则楼板展开长度超过规范规定,为了满足建筑功能要求,建筑物不允许留永久施工缝.结构整体隔震设计时,由于上部结构楼板不连续造成局部薄弱连接板.现行规范中并未对此类结构给出相关设计方法,只能通过增加板厚加强配筋等方式满足建筑要求.通过YJK和ETABS2016两个结构软件对结构楼板设计进行分析计算,...     

现浇钢筋混凝土楼板结构设计配筋与验算分析探讨

本文结合笔者多年建筑工程实践,就现浇钢筋混凝土楼板结构设计配筋与验算中存在的问题进行了详细分析,对充分考虑梁板共同作用楼板和支承梁刚度作用时的计算与配筋方式进行了详细论述,对楼板采用弹、塑性算法与配筋原则进行了深入分析探讨。     

论住宅楼板全部采用双层双向配筋的必要性和可行性

住宅工程的楼板开裂问题较为普遍,其中一个主要原因是楼板面筋不连续设置,造成钢筋网的自我支撑能力较差,负弯矩钢筋在施工荷载作用下容易失位错乱,导致楼板开裂.楼板双层双向连续配筋可有效改善这种情况.阻碍楼板双层双向连续配筋的最大障碍是工程造价的增加.通过详细计算,认为楼板双层双向连续配筋后的钢筋增量及造价增加情况非常有限,可作为减小楼板开裂的重要措施积极推行.     

湖北省图书馆新馆悬挑转换桁架结构设计

湖北省图书馆新馆为框架结构,局部设置少量支撑及剪力墙,属于平面、竖向均不规则的结构。结合概念设计和计算分析,对新馆工程上托7层悬挑转换桁架的结构布置进行了设计方案比选;分析比较了不同楼板假定对桁架弦杆的受力和配筋影响。结果表明:传力越直接,结构布置越合理;对于平面不规则或考虑温度荷载工况的结构,刚性楼板假定会产生较大误差。桁架节点复杂,设计中提出了有别于常规做法的适用节点构造。     

论住宅楼面裂缝的防治

从住宅工程现浇楼板裂缝发生的部位分析,最常见、最普通和数量最多的是房屋四周阳角处(含平面形状突变的凹口房屋阳角处)的房间在离开阳角1米左右,即在楼板的分离式配筋的角弯距筋以及部放射末端或外侧发生45度左右的楼面斜角裂缝,此通病在现浇楼板的任何一种类型的建筑中都普遍存在。     

中科院地理信息及文化产业项目结构设计

中科院地理信息及文化产业项目地理楼和文化楼为平面及竖向不规则的超限高层。针对结构平面及竖向不规则,本工程采取适当加强措施,使其具有足够的安全储备,满足结构既定的抗震能力;对于文化楼超长结构,补充楼板应力分析,按应力分析结果进行楼板配筋;三层连接两栋楼的地球仪造型钢结构平台结构体系合理,传力路径明确,经计算分析表明结构的整体位移、承载力及整体稳定均满足规范要求。     

开孔板连接件相对滑移机理试验研究

为研究组合结构桥梁中开孔板连接件的相对滑移机理,以开孔板厚度、孔中钢筋直径、开孔板孔径为变化参数,进行了21个开孔板连接件抗剪性能模型试验。通过理论分析与试验结果比较,揭示了开孔板连接件相对滑移量主要由孔中钢筋剪切变形量、孔中混凝土压缩变形量和剪切变形量三部分组成,以及抗剪承载力对应相对滑移量随板厚增加而减小,随孔径、孔中钢筋直径增加而增大的滑移机理。     

Development of a shrouded wind turbine with a flanged diffuser

We have developed a wind turbine system that consists of a diffuser shroud with a broad-ring flange at the exit periphery and a wind turbine inside it. The flanged-diffuser shroud plays a role of a device for collecting and accelerating the approaching wind. Emphasis is placed on positioning the flange at the exit of a diffuser shroud. Namely, the flange generates a low-pressure region in the exit neighborhood of the diffuser by vortex formation and draws more mass flow to the wind turbine inside the diffuser shroud. To obtain a higher power output of the shrouded wind turbine, we have examined the optimal form of the flanged diffuser, such as the diffuser open angle, flange height, hub ratio, centerbody length, inlet shroud shape and so on. As a result, a shrouded wind turbine equipped with a flanged diffuser has been developed, and demonstrated power augmentation for a given turbine diameter and wind speed by a factor of about 4-5 compared to a standard (bare) wind turbine. In a field experiment using a prototype wind turbine with a flanged diffuser shroud, the output performance was as expected and equalled that of the wind tunnel experiment.     

Time to build options in construction processes

Time to build is a very important factor in a real estate development venture. Delay in completion of a project not only affects the financing costs and the rental revenue but also it may, on a more strategic note, determine the success or failure of a project. A time to build option model consisting of a stochastic rate of completion and a stochastic net project payoff is applied to the sequential construction process of a large scale construction project. The results of the sensitivity analysis show that the optimal payoff value, that triggers the exercise of the option to invest at a maximum rate, increases positively with the increases in cash flow volatility, input cost uncertainty, excess asset return per unit risk and maximum rate of investment. However, it has a negative relationship with the rental yield. In a case study involving a commercial project, the premium for hedging the payoff risks by pre-leasing a project was estimated at 11.29%, whereas the additional cost incurred for shielding a project against input cost risks in a design and build contract was estimated at 7.80%, where each is given as a percentage of the total construction costs.     

横向流动土体作用下的群桩反应性状

借助FLAC3D程序,分析了基坑开挖后土体横向流动作用下坑内群桩的反应性状。研究了两桩、四桩、五桩、六桩群桩中基桩的反应性状,并与相同位置的单桩反应进行了比较,得到了受横向流动土体作用的群桩相互作用规律:桩基连线平行于边坡布置的两桩,相互影响并不明显;而在其它情况下,前排桩对后排桩遮拦、后排桩对前排桩阻挡,均使受影响的桩基内力分布改变,桩身最大变形量减小;受周围越多、越近桩基的影响,基桩的内力和变位减少得越多。根据桩间土体的成拱特征,定性解释了群桩相互作用的机理与规律,具体工程的现场量测结果也验证了此结论。     

J型烟囱的设计

为满足燃油锅炉的烟气排放要求，设计了Ｊ型烟囱，它由斜三通，直管，膨胀节，防爆门，雨漏、落水管道组成；给出了烟囱高度计算公式，指出烟囱设计中应注意的几个问题。实际运行表明，这种烟囱烟气排放指标符合当地环保要求。     

Inside the Eco-home: Using Video to Understand the Implications of Innovative Housing

As a method of qualitative research, video offers a means of looking into the world of a respondent and a means of stimulating a dialogue, both with the respondent and others. Video requires, however, the application of additional ethical procedures and may also increase refusal rates, if it is publicly disseminated. Applied to the home, the use of video reveals both practice and identity. Video records practice, showing how the spaces within a home are used at a particular time. For this reason, video is well adapted to understanding the implications of living in a home with an innovative design and technology, with all the complexities that this commonly involves. Equally, video communicates the appearance of the home and of its occupants to whoever is watching. Video is, therefore, intimately connected to identity and the home as a place.     

Life-cycle social analysis of motorway bridges

User costs of a bridge are the costs incurred by the users of the bridge, which result from any construction and/or maintenance activity being performed in the bridge. Typically, these costs encompass the additional time lost due to incurred congestion, the additional costs of vehicle operation and the costs of additional accidents. Usually, such costs are not considered in the procedures leading to the formulation of strategies for bridge construction, maintenance and repair, despite their relevance in comparison with the costs incurred by the agency or owner of the bridge. Moreover, in a life-cycle perspective of a bridge, with a time span over 100 years, the quantification of user costs is affected by a large number of uncertainties. Therefore, it is the purpose of this paper to introduce a life-cycle analysis for the quantification of typical user costs, in a probabilistic approach. For this purpose, the analysis of a motorway bridge in Portugal is performed. The results of the case study demonstrate that user costs can be much more important than costs supported by the concessionaire, in a life-cycle perspective, and thus, a much higher importance should be given to these costs apart from the scientific community.     

Energy landscape: Los Angeles Harbor and the establishment of oil-based capitalism in Southern California, 1871–1930

In the first three decades of the twentieth century, the Los Angeles metropolitan area emerged as the fastest growing urban–industrial economy on the Pacific Coast. This was a significant achievement for a city without a natural harbour. Despite formidable barriers presented by physical geography, the gradual development of a deep-water harbour in Los Angeles was fundamental to the emergence of oil-based capitalism in Southern California. In the first three decades of the twentieth century, under the municipal governance of a Board of Harbor Commissioners, private oil companies developed Los Angeles Harbor into a modern transhipment facility comprising infrastructures and technologies dedicated to the efficient transportation, storage, and refining of petroleum and petroleum-based products. From this perspective, Los Angeles Harbor needs to be understood as a long-term, fixed-capital investment into oil-based energy as fuel for industry and transportation. As a transhipment facility, Los Angeles Harbor also functioned as a critical outlet for surplus energy after the discovery of several large fields in the Los Angeles Basin in the early 1920s. By focusing on a particular built landscape, this paper aims to contribute insight into how geographies of fixed-capital investment play a role in the regional dynamics of energy transition and establishment.     

Nonlinear analysis and reliability of metallic truss structures

The present study goes into the search for the safety domain of civil engineering structures. The objective is to show how a reliability-evaluation brought by a mechanical sizing can be obtained. For that purpose, it is necessary to have a mechanical model and a reliability model representing correctly the behavior of this type of structure.It is a question on one hand, to propose a formulation for the nonlinear calculation (mechanical nonlinearity) of the spatial structures in trusses, and on the other hand, to propose or to adapt a formulation and a modeling of the reliability. The principle of Hasofer-Lind can be applied, in first approach, for the reliability index estimation, scenarios and the probability of failure.The made check concerned metallic in truss structures. Finally, some structures are calculated using the method adapted by Hasofer-Lind to validate the probability approach of the reliability analysis.     

Choctaw Eco-Industrial Park: an ecological approach to industrial land-use planning and design

This project investigates the concepts of industrial ecology and eco-industrial parks and applies those concepts to the redesign of an existing industrial park in Choctaw, OK. The opportunity for developing an eco-industrial park on this site comes from the availability of waste water for non-potable water needs, and the abundance of waste tires as raw materials for products to drive a new set of industrial partnerships. These industrial partnerships include the City of Choctaw Waste Water Treatment Plant, a tire shredding company, a tire pyrolysis company, a hydroponics industry, a hard rubber tire manufacturer, a screen printer, a plastics manufacturer, a toner manufacturer, and a toner cartridge manufacturer. The nature of this relationship and the design of the eco-industrial park is contained within this report. The result of this investigation is a new, common sense, approach to industrial land use that combines economic growth and environmental protection.