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91.
以某河床式水电站工程为例,在分析厂房整体结构特点的基础上,建立了三维有限元模型,并应用《水工建筑物抗震设计规范》(DL 5037-2000)和《欧洲结构抗震设计规范》(Eurocode 8)中三种不同的反应谱,进行了河床式水电站厂房结构的地震响应分析。将设计反应谱转换成20s的人造地震波,通过时程分析,对反应谱分析得到的结构应力和位移状况进行验证对比,讨论在规范规定的不同反应谱分析方法下河床式水电站厂房结构地震响应的异同。期待研究成果可以为我国抗震规范的修订提供部分借鉴。 相似文献
92.
This paper experimentally investigated the behavior of a special shaped column composed of concrete-filled steel tubes (SCFST column) subjected to a constant axial load and a cyclically varying flexural load. The effects of both the axial compression ratio and the length to width ratio on the behavior (stiffness, strength, ductility, and energy dissipation) of SCFST columns were studied. The asymmetry character of the column was studied. The connection plate was an important member transferring shear force. The mono columns of SCFST columns worked together well and the seismic behavior of SCFST columns was good. An increase of the axial compression ratio increased the stiffness with a decrease of energy dissipation ability, ductility, and bearing capacity. On the other hand, an increase of the length to width ratio led to an increase of energy dissipation ability and ductility and a decrease of stiffness and bearing capacity. Furthermore, a finite element analysis was also carried out to simulate the behavior of SCFST columns and the test results agreed with the results of finite element analysis. 相似文献
93.
The modified hyperbolic method is used in practice to predict the ultimate primary consolidation settlement of compressible ground. This paper presents a new relationship between the average degree of consolidation for combined vertical and horizontal consolidation Uvh and the non-dimensional vertical time factor Tv, with a new parameter, νhv, introduced. νhv is defined as the ratio of the time factor in the horizontal direction to that in the vertical direction. This relationship is then adopted to calculate the slope of the linear segment of the theoretical hyperbolic plot (Tv/Uvh vs Tv), λ, which is a key factor in the modified hyperbolic observational method presented by Tan (1995). A design chart for λ as a function of νhv is proposed. Using this design chart, the determination for λ can be simplified from a procedure involving three parameters to only one, νhv. A new procedure for the use of the modified hyperbolic method is proposed. The new procedure is verified using a well-documented case history. 相似文献
94.
Through tensile testing of 15 steel bolt-sphere joints and 15 aluminum alloy bolt-sphere joints, influencing rules of material type, high temperature and cooling mode on tensile properties of post-fire bolt-sphere joints were studied, and then failure modes of the joints were determined. According to experimental data, the calculation formula of residual tension capacity of post-fire bolt-sphere joints was presented. Experimental data indicated that (1) decreased extension on the mechanical properties of aluminum alloy bolt-sphere joints after high temperature in the fire was significantly higher than that of the steel bolt-sphere joints; (2) when fire temperature was lower than 800 °C, the tension capacity of steel bolt-sphere joints could be restored by more than 90% after cooling; (3) when fire temperature was lower than 500 °C, the tension capacity of aluminum alloy bolt-sphere joints could be restored by more than 50% after cooling; (4) bolt-sphere joints could still satisfy the requirement of “strong node and weak member” after a fire; and (5) material type and fire temperature were the main factors that influenced post-fire mechanical properties of bolt-sphere joints. 相似文献
95.
针对长距离引水工程建设管理中存在可控性弱、信息共享交流困难等问题,提出了 Skyline 平台集成 BIM 信息模型的方法,实现了施工进度模拟和工程量统计,通过 Skyline 软件的二次开发建立了基于网络的长距离引水工程建设管理系统。系统以三维空间大场景为可视化交互环境,为各参建方提供了一个可视化的信息共享与协同办公平台,同时实现了以进度和工程量管理为核心的八大项目管理功能,满足引水工程建设管理需求,体现了 BIM 和 GIS 融合在引水工程建设管理中的应用价值。目前系统已应用到某引水工程中,效果良好。 相似文献
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98.
以中国福建某较深海域风电场为背景,提出一种海上风电宽浅型三筒导管架基础结构,继而通过建立考虑分层土体的基础整体有限元模型,对分层土中宽浅型三筒导管架基础静动力特性及浮运稳性展开研究。研究结果表明,正常荷载作用下此基础结构法兰倾斜率为3.98‰,满足规范要求:极限荷载作用下,基础结构各部位应力满足要求;基础-塔筒-机组整体共振校核满足要求:基础可在4级风浪以内的海况下进行自浮远距离拖航浮运;等效疲劳荷载作用下,基础结构疲劳损伤满足要求。 相似文献
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