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1.
建筑物震害预测模糊震害指数法   总被引:6,自引:3,他引:6  
建筑物震害预测是城市防震减灾的基础工作之一。本文在分析现有震害预测方法的基础上,提出了一种新的震害预测方法-模糊震害指数法。模糊震害指数法以现有震害预测资料为基础,采用模糊数学方法实现。本文详细阐述了模糊震害指数法的理论模型,推导了其数学公式,最后给出了实例分析。  相似文献   

2.
崔玉红  邱虎等 《地震研究》2001,24(2):175-182
国内外单体建筑物的震害预测方法包括历史震害统计法、专家评估法、模糊类比法、半经验半理论法、结构理论计算方法和动态分析法。本首先对国内外单体建筑物震害的预测方法进行了研究论述,然后探讨了各种方法的优缺点。  相似文献   

3.
国内外单体建筑物震害预测方法研究述评   总被引:4,自引:0,他引:4  
国内外单体建筑物的震害预测方法包括历史震害统计法、专家评估法、模糊类比法、半经验半理论法、结构理论计算方法和动态分析法。本文首先对国内外单体建筑物震害的预测方法进行了研究评述 ,然后探讨了各种方法的优缺点  相似文献   

4.
架空管道震害预测实用方法的研究   总被引:1,自引:0,他引:1  
根据震害调查分析和试验研究结果,建立了由环境因素和管道结构参数组成的,对架空管道震害预测进行二级多因素模糊综合评判的方法。文中给出了计算、评价构成二级评判因素地震烈度、场地类型、工作状态和结构种类各档次正态模糊数范数ak的参数和对实际情况如何确定的方法。本文为面广量大的已建架空管道的震害预测工作提供了一套科学性强,方便实用的计算方法。  相似文献   

5.
城市群体建筑物震害模拟方法研究   总被引:2,自引:0,他引:2  
本文针对目前进行城市群体建筑物震害预测时,在数据收集和计算工作中遇到的实际困难,提出了一种简化的震害计算方法——单元破坏度指数法。同时将该计算模型嵌入到ArcView 9.0的GIS平台中,并以Oracle数据库为支撑,结合青岛市的实际数据,对城市群体建筑物的震害进行了模拟。结果表明,单元破坏度指数法不仅大大简化了数据收集和处理的工作量,而且计算结果的精度同样能满足工程应用的要求,与GIS相结合可以客观快速地模拟出城市群体建筑物的震害程度及其空间分布。  相似文献   

6.
向群 《华南地震》2004,24(1):23-27
通过二次评判法,在考虑框架结构强度、变形破坏准则的基础上,引入了房屋破损程度、施工质量等模糊因素,使框架结构的震害预测建立在既考虑可精确计量的强度、变形等因素,又考虑了诸多无法精确计量的模糊因素基础上,从而复原了震害预测的本质即概率和模糊的特性。  相似文献   

7.
目前基于地震烈度的建筑物震害预测方法,通常按整烈度给出预测结果,造成在设定地震影响下烈度分界线两侧相邻的、抗震能力相同的建筑物震害预测结果有很大的差异,而同一烈度圈内靠近高烈度分界线与靠近低烈度分界线的建筑物震害预测结果却完全相同,这与实际震害情况严重不符。为了解决这个问题,将地震烈度按0.2度间隔进行分档,同时将震害指数和破坏等级也进一步细化出5个分档。按地震烈度与震害指数的关系,通过拟合方法和等分方法得到5个烈度分档的震害指数调整系数和分档震害指数,拟合方法获得的调整系数适用于群体房屋震害预测,等分方法获得的震害指数适用于单体房屋震害预测,通过改进方法获得的设定地震影响下震害预测结果,可以体现同一烈度不同烈度分档内建筑物震害差异,并使烈度线两侧,抗震能力相同的建筑物的震害预测结果不再出现跃变。  相似文献   

8.
地下管道震害预测实用方法的研究   总被引:2,自引:2,他引:2  
本文根据震害调查分析和试验研究结果,建立了由环境因素和管道结构参对地下管道震害进行二级多因素模型综合评判的方法,文中给出了计算,评价构成二级评判因素地震烈,场地类型,工作状态和结构种类正态模糊范数ak的方法,并在地下管道震害关联分析和试验基础上,给出了二级模糊评判的权向量,本文为面广量大的已那建下管道的震害预测工作提供了一套方便实用的计算方法。  相似文献   

9.
钢筋混凝土耗能支撑框架结构的震害预测   总被引:1,自引:0,他引:1  
首先介绍了一种新的震害预测方法——基于模糊概率的震害预测模型。在分析了钢筋混凝土框架结构抗震性能以及摩擦耗能支撑框架结构在地震作用下力学性能的基础上,提出用结构层间屈服强度系数、层间剪切位移角和地震损伤指数这三个指标作为其主要震害影响评价因子。同时,利用所提出的预测方法,建立了钢筋混凝土耗能支撑框架结构房屋的震害预测模型。  相似文献   

10.
展望建筑物震害预测的发展方向   总被引:2,自引:1,他引:2  
本文回顾了我国 建筑物震害预测研究和应用的发展过程,评论了各种预测方法的优缺点,指出了各家建议预测方法存在的不确定性,针对存在的问题,提出了减少消除物震害预测方法中不确定性的途径。最后,展望了建筑物震害预测在的实用前景和发展方向。  相似文献   

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《国际泥沙研究》2014,(4):F0003-F0003
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14.
《国际泥沙研究》2014,(2):F0003-F0003
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15.
《国际泥沙研究》2014,(3):F0003-F0003
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17.
The partitioning of rain water into throughfall, stemflow and interception loss when passing through plant canopies depends on properties of the respective plant species, such as leaf area and branch angles. In heterogeneous vegetation, such as tropical forest or polycultural systems, the presence of different plant species may consequently result in a mosaic of situations with respect to quantity and quality of water inputs into the soil. As these processes influence not only the water availability for the plants, but also water infiltration and nutrient leaching, the understanding of plant effects on the repartitioning of rain water may help in the optimization of land use systems and management practices. We measured throughfall and stemflow in a perennial polyculture (multi‐strata agroforestry), monocultures of peach palm (Bactris gasipaes) for fruit and for palmito, a monoculture of cupuaçu (Theobroma grandiflorum), spontaneous fallow and primary forest during one year in central Amazonia, Brazil. The effect on rain water partitioning was measured separately for four useful tree species in the polyculture and for two tree species in the primary forest. Throughfall at two stem distances, and stemflow, differed significantly between tree species, resulting in pronounced spatial patterns of water input into the soil in the polyculture system. For two tree species, peach palm for fruit (Bactris gasipaes) and Brazil nut trees (Bertholletia excelsa), the water input into the soil near the stem was significantly higher than the open‐area rainfall. This could lead to increased nutrient leaching when fertilizer is applied close to the stem of these trees. In the primary forest, such spatial patterns could also be detected, with significantly higher water input near a palm (Oenocarpus bacaba) than near a dicotyledonous tree species (Eschweilera sp.). Interception losses were 6·4% in the polyculture, 13·9 and 12·3% in the peach palm monocultures for fruit and for palmito, respectively, 0·5% in the cupuaçu monoculture and 3·1% in the fallow. With more than 20% of the open‐area rainfall, the highest stemflow contributions to the water input into the soil were measured in the palm monocultures and in the fallow. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   

18.
A procedure for short-term rainfall forecasting in real-time is developed and a study of the role of sampling on forecast ability is conducted. Ground level rainfall fields are forecasted using a stochastic space-time rainfall model in state-space form. Updating of the rainfall field in real-time is accomplished using a distributed parameter Kalman filter to optimally combine measurement information and forecast model estimates. The influence of sampling density on forecast accuracy is evaluated using a series of a simulated rainfall events generated with the same stochastic rainfall model. Sampling was conducted at five different network spatial densities. The results quantify the influence of sampling network density on real-time rainfall field forecasting. Statistical analyses of the rainfall field residuals illustrate improvement in one hour lead time forecasts at higher measurement densities.  相似文献   

19.
Red tide, a recurrent phenomenon has become conspicuous in several Kashmir lake ecosystems since 1991. The responsible organism (Euglena pedunculata), a rare flagellate rediscovered in the Kashmir Himalaya (Khan 1993) caused first and unprecedented red tide outbreak, constituting a maximum of 96% of resident numerical phytoplankton density in Dal Lake. At present, conflicting hypotheses exist on the generation of causal assemblage(s) imparting redness to waters: Jeeji Bai (1991) linked its origin to acid precipitation – a fallout of burning oil‐fields during the Gulf War – whilst Khan (1993) holds local factor(s) responsible. Field/experimental studies support the latter contention that the influx of untreated sewage, in unison with warm temperatures, high levels of PhAR, iron and interruption to hydrological flow‐pattern together with absence/or reduction in grazing activity created conducive environmental milieu for red tide outbreak. Dal Lake “red tide” drifted the bloom‐inoculum to other waters, including Lake Wular, where additional ecological niches were carved out, threatening the aesthetic value and biological diversity of Kashmir lakes. Ecological monitoring indicates frequent seasonal red tide occurrence in Dal Lake (including summer‐autumn event of 1998) which testifies its unabated eutrophication status. Further studies are needed on ecological adaptability and biogeographic distribution of this rare and unique red tide‐causing flagellate.  相似文献   

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