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101.
The local design and construction practices in the United Arab Emirates(UAE),together with Dubai’s unique rate of development,warrant special attention to the selection of Lateral Force-Resisting Systems(LFRS).This research proposes four different feasible solutions for the selection of the LFRS for tall buildings and quantifies the impact of these selections on seismic performance and cost.The systems considered are: Steel Special Moment-Resisting Frame(SMRF),Concrete SMRF,Steel Dual System(SMRF with Special Steel Plates Shear Wall,SPSW),and Concrete Dual System(SMRF with Special Concrete Shear Wall,SCSW).The LFRS selection is driven by seismic setup as well as the adopted design and construction practices in Dubai.It is found that the concrete design alternatives are consistently less expensive than their steel counterparts.The steel dual system is expected to have the least damage based on its relatively lesser interstory drifts.However,this preferred performance comes at a higher initial construction cost.Conversely,the steel SMRF system is expected to have the most damage and associated repair cost due to its excessive flexibility.The two concrete alternatives are expected to have relatively moderate damage and repair costs in addition to their lesser initial construction cost. 相似文献
102.
The target of this study is the evaluation of repair mortar contribution to the dynamic behavior of Kaisariani Monastery in Athens, by using the tools of finite element analysis and fragility curves. Three types of mortars (concrete) are designed in order to simulate the Hagia Sophia historic mortar, by using different binding material: lime/metakaolin, hydraulic lime, lime/cement. In the developed model the mechanical characteristics of the designed mortars are used. In addition, fragility curves were developed and their results indicated that for the current situation of Kaisariani Monastery and for peak ground acceleration (PGA) value ≥0.24 g, the probability of occurrence of serious damage is 59%. For PGA=0.36 g an overall failure happened. For PGA=0.40 and by using restoration mortar up to 15% of the total bed joint the failure percentage reduces in the range of 12–30%. Better protection is reported for lime/cement mix design followed by hydraulic lime and lime/metakaolin. 相似文献
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文章针对S波段双偏振天气雷达设计了一种改良的标准差分析方法,用以评估雷达数据质量,通过评估2022年2月-10月成都雷达基数据的数据质量,得到了如下结果:(1)对于正常雷达数据,改良的标准差计算方法与原始方法能得到相同趋势的标准差分布结果,计算异常雷达数据的标准差时,能得到更优的标准差分布结果。(2)成都雷达Zh数据质量存在较大波动,标准差低于SDZh标准值的比例仅43.67%。(3)成都雷达Zdr和CC数据质量较好,标准差低于SDZdr和SDCC标准值的比例分别为84.09%和87.10%,φdp的数据波动较大,标准差低于SDφdp上限的比例仅34.54%。 相似文献
107.
Jason McCormick Takuya Nagae Masahiro Ikenaga Peng‐Cheng Zhang Mika Katsuo Masayoshi Nakashima 《地震工程与结构动力学》2009,38(12):1401-1419
The friction developed between a steel base plate and a mortar base contributes shear resistance to the building system during a seismic event. In order to investigate the possible sliding behavior between the base plate and the mortar, a shake table study is undertaken using a large rigid mass supported by steel contact elements which rest on mortar surfaces connected to the shake table. Horizontal input accelerations are considered at various magnitudes and frequencies. The results provide a constant friction coefficient during sliding with an average value of approximately 0.78. A theoretical formulation of the friction behavior is also undertaken. The theoretical equations show that the sliding behavior is dependent on the ratio of the friction force to the input force. The addition of vertical accelerations to the system further complicates the sliding behavior as a result of the varying normal force. This results in a variable friction resistance which is a function of the amplitude, phase, and frequency of the horizontal and vertical input motions. In general, this study showed a consistent and reliable sliding behavior between steel and mortar. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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Structural damage in buildings designed according to the dissipative design philosophy can be significant, even under moderate earthquakes. Repair of damaged members is an expensive operation and may affect building use, which in turn increases the overall economic loss. If damage can be isolated to certain dissipative members realized to be removable following an earthquake, the repair costs and time of interruption of building use can be reduced. Dual structural configurations, composed of a rigid subsystem with removable ductile elements and a flexible subsystem, are shown to be appropriate for the application of removable dissipative element concept. Eccentrically braced frames with removable links connected to the beams using flush end‐plate bolted connections are investigated as a practical way of implementing this design concept. High‐strength steel is used for members outside links in order to enhance global seismic performance of the structure by constraining plastic deformations to removable links and reducing permanent drifts of the structure. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
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极限平衡分析方法是斜坡稳定性评价中的常用方法,在长期的工程实践中积累了丰富的经验,但其不能考虑斜坡岩土体中实际存在的不确定性,在应用中具有一定的局限性。可靠度分析方法可有效地考虑斜坡系统内的不确定性和相关性,但因状态函数偏导数的求解比较困难,使可靠度分析方法在实际中应用不便。为解决上述问题,根据二元函数插值逼近原理,在矩形区域上构造拉格朗日不完全双二次多项式逼近状态函数,从而近似地计算状态函数的偏导数,求得状态函数的均值和方差,并利用精度较高的一次二阶矩方法来计算斜坡的可靠指标和破坏概率。据鄂西恩施地区马堡营滑坡实例分析表明,引入二元函数插值逼近的一次二阶矩方法计算结果与剩余推力法及Monte-carlo模拟方法结果一致,其精度可满足工程需求。 相似文献
110.
岩溶裂隙介质可视为双重孔隙度介质。根据水流连续性原理、质量守衡和达西定律,建立了裂隙-岩溶承压含水层非稳定流双重介质数学模型,采用有限体积法对其求解,并以深圳龙岗区为例对模型进行验证。结果表明,计算模型与实际水文地质条件比较接近,计算水位与实测水位相吻合。 相似文献