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481.
设计并制作了动力特性基本一致的90°螺旋型和方形截面高层建筑的多自由度气弹模型,对气弹模型进行了风洞试验。运用随机减量法识别了顺、横风向以及多风向角下的气动阻尼;对出现了"拍"现象的工况采用小波方法解耦模态后再进行气动阻尼识别。风洞试验结果表明,方形截面高层建筑顺、横风向气动阻尼比随折算风速的变化规律与相关研究结果类似;螺旋型高层建筑顺风向气动阻尼比随折算风速的变化规律与方形截面高层建筑较为接近,在高折算风速段的阻尼比值相比方形截面高层建筑偏小,横风向气动阻尼比在低折算风速段微弱上升,随后下降,在0值附近波动。对多个风向角的加速度响应进行研究,螺旋型高层建筑均表现出良好的气动性能,尤其在横风向折算风速为12.43时,其加速度均方根为方形截面高层建筑的25.48%。  相似文献   
482.
多层砌体房屋抗震加固方法述评   总被引:3,自引:0,他引:3  
本文讨论了多层砌体房屋抗震加固的原则,对目前常用的多层砌体房屋的加固方法进行了简要的论述,提出了各种方法的特点和适用范围以及需要注意的问题,并指出了将来可能的发展方向。  相似文献   
483.
This study assesses the effects of a high rise building on the beach and dune at an intensively developed shoreline through field investigation of geomorphological and sedimentological characteristics and wind tunnel investigation of wind speed and direction. Results indicate that wind speed is increased close to the building, where wind is often deflected to a more onshore direction. Obliquely offshore northwesterly winds are the most dramatically altered and cause onshore flows (with pronounced upward flows) in the landward portion of the beach near the building. Onshore deflections in wind direction cause besanding of the boardwalk and create highly localized scour and deposition zones. A dune on the backbeach breaks up zones of sediment transport and scour and diminishes the likelihood that scour areas will cause increased hazard to landward buildings as a result of flooding. Generic large-scale studies are required to develop criteria for communities to use to specify optimum dimensions, locations and shapes of landforms that are modified or created by high rise structures.  相似文献   
484.
多尺度全卷积神经网络建筑物提取   总被引:1,自引:1,他引:0  
针对VGG16网络在高空间分辨率遥感影像中进行大型建筑物提取时存在空洞的现象,提出一种基于多尺度影像的建筑物提取方法。将原始影像进行不同尺度的下采样,提取不同尺度下的建筑物特征,并将这些多尺度特征相加合并,同时为了减少网络参数数量,用全卷积上采样过程代替原始VGG16网络中的全连接层进行建筑物提取。以0.5 m分辨率的上海市嘉定区影像和1 m分辨率的Massachusetts地区影像进行试验,精度分别达97.09%和96.66%,表明本文方法的有效性。  相似文献   
485.
孙锐  张佳琳  于东杰 《中国地震》2022,38(4):785-798
医疗类建筑是抗震救灾的重要场地,如何保证医疗建筑在发生地震时实现“大震不倒”甚至“功能不中断”,成为值得研究的关键问题。对于位于发震断层附近的医疗类建筑,本文以实际项目为例,采用粘滞阻尼器作为一种消能减震的手段,将减震结构与非减震结构在多遇地震和罕遇地震工况下的地震响应进行对比。结果表明:多遇地震工况下,粘滞消能器发生轴向拉压变形开始耗能,能够提供3%的附加阻尼比,主体结构地震力减小,结构构件尺寸较非减震结构能够更好地满足医疗建筑的使用要求;罕遇地震工况下,设置粘滞消能器的结构XY向最大层间位移角分别为1/214和1/230,结构塑性铰分布满足“强柱弱梁”的设计准则,整体结构基本满足“大震下功能不中断”的性能要求。  相似文献   
486.
There is currently an expansion of local energy initiatives, underpinned by the desire to reduce energy-related carbon emissions and in recognition of the importance of the local arena to achieving such change. Much of the research on these initiatives has been framed by a conventional economic approach, identifying barriers, drivers and incentives to explain their emergence (or not). Here a new economic sociological approach is taken which sees markets as socio-materially constructed and points to the importance of tracing exchange flows and determining modalities of valuation for such exchanges. Artefacts or market devices are seen to play a particular role in connecting actors and technologies within coordinating institutional arrangements and offer the potential for making innovative projects conventional. These aspects are explored in four international case-studies from Wales, Sweden, Germany and USA, mapping relations, identifying exchange flows, pinpointing how artefacts coordinate and showing the multiple modalities of valuation involved in each case. Conclusions concerning the importance of negotiation against a market backdrop and rendering exchange flows more certain are drawn.  相似文献   
487.
This paper applies the ecological modernization (EM) framework to analyze China’s green building program. EM focuses on the effective institutionalization of environmental objectives into respective political and economic systems, and thus provides valuable insights into the roles of the state and other stake holders in environmental regulation. Since the mid-2000s, the Chinese government has advanced an aggressive green building campaign, which is distinguished by its speed, scale, and evolution from one of voluntary participation to a top-down implementation through administrative hierarchies. While this has resulted in a remarkable growth of green building projects, questions remain about the effectiveness and sustainability of such a state-centered approach. Though interviews with officials, planners, architects, real estate developers, and property managers in several Chinese cities, data analysis of the green building stock, and surveys of architects, this paper analyzes Chinese green building patterns and situates such patterns among the contradictory motivations of different levels of government and their relationships to different stake holders. This research finds that the top-down state apparatus is not sufficient to overcome these contradictions and the profit motives of the property developers. However, many under-developed opportunities exist to leverage property developers, building professionals, and the public to engage in green building practices. In the end, I argue that the state must embrace reform to build flexible and collaborative movements with other parties with strong public participation. China’s ecological modernization process may feature a stronger state and faster changes, but it is not exempted from the need of political modernization.  相似文献   
488.
在对拉德芳斯小区沉降监测研究的背景下,结合所学知识,设计了基于该小区高层建筑物的沉降监测方案,并进行了高楼倾斜的相关计算,为该小区的施工及竣工后的投产使用安全提供依据。  相似文献   
489.
三维建筑物是三维电子地图的重要组成要素,现有的网络地图普遍采用Web GL技术在地图上展现建筑物三维效果。本文则采用开源纯Java Script技术的OSM Buildings三维建筑物引擎实现在传统二维电子地图上添加三维建筑物并支持在浏览器中以无插件的方式浏览3D场景。全文详细叙述了三维建筑物所用底图数据的采集、校正、投影以及将底图数据转换成OSM Buildings所支持的Geo JSON格式的过程。  相似文献   
490.
机载LIDAR技术解决了如何快速、准确地获取地物高度的难题,同时为地物高度信息的应用提供了有效的技术手段。本文根据地理国情普查中建筑物分类指标体系,分析离散点云数据高程关系和分类过程,实现了一种基于点云阶层式分类的城市建筑物高度分级的技术方法,并在Terrascan软件环境下验证了该方法的可行性和快速性。  相似文献   
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