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991.
?????????LiDAR?????з??????????????????y????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????Χ??????????????????????????С?????????????????????????С???????????3???????????????????????????????Ч??????????????????????????????????92%?? 相似文献
992.
A fuzzy‐logic control algorithm, based on the fuzzification of the MR damper characteristics, is presented for the semiactive control of building frames under seismic excitation. The MR damper characteristics are represented by force–velocity and force–displacement curves obtained from the sinusoidal actuation test. The method does not require any analytical model of MR damper characteristics, such as the Bouc‐Wen model, to be incorporated into the control algorithm. The control algorithm has a feedback structure and is implemented by using the fuzzy‐logic and Simulink toolboxes of MATLAB. The performance of the algorithm is studied by using it to control the responses of two example buildings taken from the literature—a three‐storey building frame, in which controlled responses are obtained by clipped‐optimal control and a ten‐storey building frame. The results indicate that the proposed scheme provides nearly the same percentage reduction of responses as that obtained by the clipped‐optimal control with much less control force and much less command voltage. Position of the damper is found to significantly affect the controlled responses of the structure. It is observed that any increase in the damper capacity beyond a saturation level does not improve the performance of the controller. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
993.
Structural performance of a base-isolated reinforced concrete building subjected to seismic pounding
The effects of seismic pounding on the structural performance of a base-isolated reinforced concrete (RC) building are investigated, with a view to evaluate the influence of adjacent structures and separation between structures on the pounding response. In particular, seismic pounding of a typical four-story base-isolated RC building with retaining walls at the base and with a four-story fixed-base RC building is studied. Three-dimensional finite element analyses are carried out considering material and geometric nonlinearities. The structural performance of the base-isolated building is evaluated considering various earthquake excitations. It is found that the performance of the base-isolated building is substantially influenced by the pounding. The investigated base-isolated building shows good resistance against shear failure and the predominant mode of failure due to pounding is flexural. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
994.
在大气边界层风洞进行了"珠江城"商务写字楼大比例尺(1:150)模型风洞试验,通过对风洞试验数据分析,获得了基础等效静风荷载及结构顶部风致加速度响应。并将其结果与其它较小比例尺的两个风洞试验结果相对比,分析了模型几何缩尺比、周边建筑及平均风剖面对试验结果的影响。获得的结果可以为此结构设计提供风荷载,同时也为其他建筑的抗风设计和风洞实验提供技术参考。 相似文献
995.
邓敏贞 《资源与生态学报(英文版)》2012,3(2):183-191
建筑是能源消耗大户,也是导致环境污染与气候变化的原因之一.推动绿色建筑的发展,是实现低碳经济与可持续发展的重要路径.当前,中国已经颁布了一些法律法规以及通过信息工具——绿色建筑认证等制度措施来推动绿色建筑的发展,但是实践中存在一些问题,相关制度设计也不够成熟.美国以及欧盟在绿色建筑方面的立法与实践经验相对比较丰富.中国可以借鉴这些国家的一些成功经验,采取一些措施促进绿色建筑的发展,如提高人们对绿色建筑的认识,设计出更多样化的激励工具等等. 相似文献
996.
997.
Comprehensive analysis and artificial intelligent simulation of land subsidence of Beijing, China 总被引:3,自引:0,他引:3
Mechanism and modeling of the land subsidence are complex because of the complicate geological background in Beijing, China. This paper analyzed the spatial relationship between land subsidence and three factors, including the change of groundwater level, the thickness of compressible sediments and the building area by using remote sensing and GIS tools in the upper-middle part of alluvial-proluvial plain fan of the Chaobai River in Beijing. Based on the spatial analysis of the land subsidence and three factors, there exist significant non-linear relationship between the vertical displacement and three factors. The Back Propagation Neural Network (BPN) model combined with Genetic Algorithm (GA) was used to simulate regional distribution of the land subsidence. Results showed that at field scale, the groundwater level and land subsidence showed a significant linear relationship. However, at regional scale, the spatial distribution of groundwater depletion funnel did not overlap with the land subsidence funnel. As to the factor of compressible strata, the places with the biggest compressible strata thickness did not have the largest vertical displacement. The distributions of building area and land subsidence have no obvious spatial relationships. The BPN-GA model simulation results illustrated that the accuracy of the trained model during fifty years is acceptable with an error of 51% of verification data less than 20 mm and the average of the absolute error about 32 mm. The BPN model could be utilized to simulate the general distribution of land subsidence in the study area. Overall, this work contributes to better understand the complex relationship between the land subsidence and three influencing factors. And the distribution of the land subsidence can be simulated by the trained BPN-GA model with the limited available dada and acceptable accuracy. 相似文献
998.
建筑物不均匀震陷影响因素研究 总被引:5,自引:2,他引:3
利用以往提出的建筑物不均匀震陷简化分析方法对不均匀震陷的几种影响因素进行了综合分析,考虑土层分布、建筑物荷载分配以及输入地震波波形和大小的不同组合,得到了一些有益的结果。 相似文献
999.
高科技厂房精密仪器工作平台的微振混合控制 总被引:2,自引:1,他引:1
车辆运行过程中引起的竖向地面微幅振动是影响高科技厂房精密仪器正常运行的重要因素。本文采用隔振与主动控制相结合的混合控制系统,以高科技厂房及精密仪器工作平台的有限元动力方程为基础,采用子优化控制方法建立了高科技厂房及精密仪器工作平台的分析模型,探讨了车辆运行所引起的高科技厂房精密仪器工作平台竖向微幅振动的混合控制分析方法。一座典型的三层高科技厂房的算例分析表明,采用混合控制方法能够有效地减小高科技厂房精密仪器工作平台的竖向微幅振动。 相似文献
1000.
高位转换框支剪力墙高层建筑抗震性能研究 总被引:11,自引:2,他引:9
本文通过对一个1:25比例的高位转换框支剪力墙结构高层建筑模型的模拟地震振动台试验,分析研究了高位转换高层建筑的自振特性、阻尼比、地震反应特征、破坏形态和破坏机理。应用三维有限元程序对结构的抗震性能进行了深入探讨,试验与计算值符合较好。成果可供高位转换结构设计和编制有关规程时参考。 相似文献