Seismic hazard assessment for the Itoiz dam site (Western Pyrenees,Spain)     

J. García-Mayordomo  J.M. Insua-Arévalo 《Soil Dynamics and Earthquake Engineering》2011

This work summarises the seismic hazard analysis performed for the complete characterisation of strong ground-motion at the site of the Itoiz dam (Western Pyrenees, Spain). The hazard analysis includes the compilation of a composite catalogue from French and Spanish agencies, the definition of an original hybrid seismogenic source model (including zones and major faults) and the selection of ground motion prediction equations (GMPEs). Hazard results are provided as hazard curves and acceleration response spectra on rock for the 1000- and 5000-year return periods, which correspond respectively to the operating basis earthquake (OBE) and safety evaluation earthquake (SEE). The impact of truncating GMPEs at a number of standard deviations (epsilon) has been found not critical here for the return periods targeted. Subsequently, an analysis of the contribution of each source to total hazard and a hazard disaggregation analysis are performed in order to establish the earthquake-source parameters for both the OBE and SEE scenarios consistently with the seismotectonics of the region. The European Strong Motion database is then searched and a selection of records is proposed for each of the scenarios. Our results suggest that seismic hazard in the region is underestimated by the official Spanish seismic hazard map included in the current version of the code (NCSE-02), which is the reference document for the definition of seismic actions for dam projects in the whole Pyrenees.  相似文献   

公路工程地质遥感勘察     

詹云军  李定平 《云南地质》2002,21(4):437-443

卫星遥感技术应用在公路选线中，具有常规方法无可比拟的优势。在湖南省常德-吉首高速公路初勘研究中，以正射航空相片，Landsat-TM数字图像为主要信息源，通过数据处理和地学遥感判释，并综合分析其它资料，对常吉公路沿线地区进行了地质构造。地层，地貌。地表水，第四系等遥感专题调查。探讨分析了不良地质现象分布规律。形成背景及发展演化趋势。在此基础上比较各设计线路之优缺点。并提出科学合理的建议线路方案。方法对自然条件十分复杂的西部公路建设有较好的借鉴意义。  相似文献   

Allozyme genotypes and tolerance to copper stress in Hediste diversicolor (Polychaeta: Nereididae)     

Virgilio M  Abbiati M 《Marine pollution bulletin》2004,49(11-12):978-985

This study analysed the occurrence of genotypic shifts in laboratory populations of Hediste diversicolor (Polychaeta: Nereididae) exposed to copper stress. Specimens of H. diversicolor were collected at three sites, up to 10 km apart, in the estuarine area of the Pialassa lagoons (North Adriatic Sea, Italy) and were used in acute toxicity tests. Specimens were assigned to copper exposure (0.34 mg/l Cu2+) or control conditions. Each combination of Treatment and Site was replicated in two tanks containing 35 specimens of H. diversicolor. The genotypic structure of both dead and survived specimens was analysed by allozyme electrophoresis at six loci (ALD, FH, HBDH LDH, PGI, SDH). Under copper exposure, specimens with the genotypes ALD100/100 and PGI102/102 had significantly lower mortalities than other genotypes Results were consistent across the three sites, suggesting that, under laboratory conditions, effects of copper stress on H. diversicolor is related to individual genotypes at ALD and PGI loci.  相似文献   

边角后方交会的精度分析及布设方案选择   总被引：8，自引：2，他引：6  

李全信 《测绘工程》2000,9(3):48-52

在推出边角后方会简捷精度估算式的基础上,分析并给出了待定点较优的选择区域,还讨论了其解的多值性问题及实质,针对边角后方交会应用中有较严格的布点限制,提出了双边单角后方交会的布设方案;文中给出了其点位与精度计算的固定公式,并附有实例难证。  相似文献   

上海市桩基础的桩型选择问题     

张剑锋  华镇难 《上海国土资源》1988,(3)

本文介绍了上海市桩基础的常用桩型及其特性,并进行了经济性和实用性的比较;提出了上海桩型需要改进和进一步发展的意见,提出了几种尚未采用的新桩型,这些新的桩型在技术和经济性方面可能是有竞争力的。  相似文献   

核废料处置库选址过程中自然灾害风险性评价     

吴伟成  艾桂根 《华东地质学院学报》1995,(3)

自然灾害是给人类及其设施带来严重灾难的危害。本文试图在了解灾害的危害性基础上，以火山作用为例，在核废料处置库选址中，通过圈定灾害高发区、确定风险评价参数、划出高风险区及风险等级三步骤，对灾害风险性进行评价。  相似文献   

测绘工程专业毕业设计（论文）选题质量控制     

吉长东 《测绘与空间地理信息》2011,(6):25-26

＂指导学生撰写毕业设计（论文）是实现培养目标的重要教学环节,具有不可替代的作用,‘决不能降低要求,更不能放任自流’＂[1]。毕业设计（论文）一般经过选题、过程控制和答辩等几个环节,文章结合我院测绘工程专业多年毕业设计（论文）实际,着手研究选题环节的质量控制,对提高毕业设计（论文）的质量,适应我校应用创新型学生培养方案,...  相似文献   

一种基于Voronoi图的人防警报器空间选址算法     

王峰  王惠  赵耀强  夏飞 《地理信息世界》2012,10(2):81-84

首先通过声学传播原理研究了警报器覆盖范围模型,结合Voronoi图影像范围、最大空心圆策略和平面完全剖分等特性,提出了基于Voronoi图的警报器空间选址算法。文章详细阐述了算法基本思想和流程,最后进行了算法组件设计和系统开发实践。实践表明采用该算法能满足城市警报器合理选址和适当重叠覆盖的要求,并具有其优越性。  相似文献   

Selection of earthquake ground motion records: A state-of-the-art review from a structural engineering perspective     

Evangelos I. Katsanos  Anastasios G. SextosGeorge D. Manolis 《Soil Dynamics and Earthquake Engineering》2010

This paper reviews alternative selection procedures based on established methods for incorporating strong ground motion records within the framework of seismic design of structures. Given the fact that time history signals recorded at a given site constitute a random process which is practically impossible to reproduce, considerable effort has been expended in recent years on processing actual records so as to become ‘representative’ of future input histories to existing as well as planned construction in earthquake-prone regions. Moreover, considerable effort has been expended to ensure that dispersion in the structural response due to usage of different earthquake records is minimized. Along these lines, the aim of this paper is to present the most recent methods developed for selecting an ‘appropriate’ set of records that can be used for dynamic analysis of structural systems in the context of performance-based design. A comparative evaluation of the various alternatives available indicates that the current seismic code framework is rather simplified compared to what has actually been observed, thus highlighting both the uncertainties and challenges related to the selection of earthquake records.  相似文献   

Constraining water age dynamics in a south-eastern Australian catchment using an age-ranked storage and stable isotope approach     

Alexander J.V. Buzacott  Ype van der Velde  Claudia Keitel  R. Willem Vervoort 《水文研究》2020,34(23):4384-4403

Improving our knowledge of the travel times of water through catchments is critical for the management and protection of water resources and to improve our understanding of fundamental catchment behaviour. In this study we use the age-ranked storage framework StorAge Selection (SAS) to investigate travel times in the Corin catchment, a headwater catchment in the south-east of Australia covered by native Eucalyptus species. Few studies have applied the SAS framework globally and in energy-intensive areas where catchment losses are heavily in favour of evapotranspiration relative to streamflow. A combination of observed and modelled values of oxygen-18 (δ¹⁸O ), the stable isotope in water, are used to constrain storage selection preferences of streamflow and evapotranspiration and the size of the catchment active storage. The highest performing parameter combinations that could reproduce δ¹⁸O in streamflow were dependent on a strong preference for young water in evapotranspiration, and a mixture of weak young and old water preference in streamflow. The mean travel time of streamflow over the study period 2007–2019, weighted by the flow rate, is limited to within a probable range of 2.81–9.77 years. The size of the active storage, a key parameter in the SAS framework, was poorly identified, and in combination with the isotopic inputs into the model, contributed to the uncertainty of the results. We discuss the implications of the results with respect to the study area, as well as within the context of SAS research globally and identify ways to improve the modelling process.  相似文献