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81.
82.
汶川地震滑坡损毁土地复垦关键技术——以北川县陈家坝乡灾后土地复垦项目为例 总被引:1,自引:1,他引:0
在对四川地震灾区北川县陈家坝乡损毁土地实地调查的基础上,根据损毁土地成因,分析滑坡损毁土地的基本特征,提出其土地复垦的关键技术主要为截一排一堵。 相似文献
83.
地震是具有突发性、破坏性的灾害,建筑物在地震的作用下,顷刻间会造成严重的经济损失,尤其是对人类的生命财产带来严重的威胁。因此,如何减少地震作用对建筑物造成的破坏,已成为该领域的重要研究课题之一,而基础隔震技术的发展,为建筑结构的抗震设计与研究开辟了一个新途径。 相似文献
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85.
"5·12"汶川地震后,大量财政资金涌入灾区用于灾后重建工作。在新农村建设背景下,通过实地走访调查,分析了绵阳、江油两地财政资金的筹措与运用现状,及灾区新农村建设财政资金使用中存在的问题,并提出相应的政策建议。 相似文献
86.
The dynamic finite element method is used to analyzes the influence on dynamic characteristic of the slope by soft soil layer. The parameters which influencing the earthquake response of the slope, including the depth, the thickness, the obliquity of soft soil layer are analyzed. The influence of soft soil layer is obvious, which must be thought over in the analysis of slope stability. The thicker the soft soil layer is, the more obvious the filter and the amplitude effect is. The deeper the soft soil layer is, the more obvious the filter effect is. The filter effect of the obliquity of the soft soil layer to dynamic time history is not obvious. 相似文献
87.
In this paper, the application of modulated ARMA model in simulation of artificial earthquake waves is discussed on the several aspects such as determination of the ARMA model orders, determination of the ARMA model parameters and influence of the initial random series. It is shown from the calculation that the influence of the intensity envelop function on the frequency characteristic of the modulated ARMA model is acceptable and the modulated ARMA model is still an efficient alternative method to generate artificial earthquake wave in practice. 相似文献
88.
基于遥感技术宏观数据快速获取能力以及地理信息系统提供的强大空间分析能力,建立了地震移民选址的空间分析模型,对研究区的数据进行迁建适宜度分区处理,并在此基础上进行了候选区模糊综合评判.并以汶川绵虒镇为研究区,对地质安全、地形地貌、水系分布、自然人文保护、交通运输、城镇建设、发展潜力等7个一级指标,以及活断层、地质灾害、土地覆盖、生态环境保护、旅游资源等15个二级指标进行了分析处理,选址结果合理,能够为地震移民选址的科学决策提供辅助数据. 相似文献
89.
确定泥石流激发雨量阈值以及建立有效的预警预报等级是泥石流防灾减灾的重要手段之一。就2008—2013年汶川灾区群发性、局部地区暴发的泥石流雨量过程进行分析,分别得到北川、清平、都江堰、映秀4个地区泥石流暴发的“雨强-历时”阈值。其中,都江堰地区阈值较高,映秀最低;北川地区群发性泥石流阈值较局部地区要高,而其他3个地区不明显,部分地区群发性泥石流I-D值还低于局部地区泥石流I-D值。根据群发性和局部区域泥石流暴发的雨强-历时、前期降雨+实时降雨关系,初步建立了以上4个地区的预警预报等级,以期能为该区泥石流预警预报提供参考。 相似文献
90.
A number of landslides were triggered by the Wenchuan earthquake on May 12 2008. The damage caused by these landslides was even more than that by earthquake. Systematic landslides inventory, as a basic technique for landslide study, can provide applicable data to quantify the study of landslides. A lot of earthquake-induced landslides were concentrated in Yingxiu meizoseismal area of 5.12 Wenchuan Earthquake. By means of post-earthquake aerial photo and satellite imagery interpretation and field investigation, this paper gets the information including locations, types and morphometry about 1948 earthquake-induced landslides within the Yingxiu Meizoseismal area (about 109.3 ㎞ 2) and inventoried them with GIS software. Then, overlay analyses are used between these landslides inventory data and environmental factors such as slope aspect, slope angle, distance from ridge, geologic units and lithology, distance from epicentre and seismogenic fault. The results show that: Landslides are triggered by earthquake scatter predominantly in the range of 30°~50°, and the landslide density is positively correlated with slope angle. Areas nearby ridge are of high landslide density indicating that amplification effect of ridge on seismic wave is an important reason of slope failure. Earthquake-induced landslide development level in Pengguan complex is higher than that in sedimentary petrologic province. Landslide density is the single exponential negative correlation with distance from epicentre and seismogenic fault indicating that earthquake-induced landslide development level in hanging wall of seismogenic fault is higher than that in footwall, and the results predicted by regression correlation agree with the existing research findings. 相似文献