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171.
动态监测方法在理论上是可行的,方法也是简便的,有着广阔的发展前景,但是,由于结构的复杂性,测量技术的局限性,单纯依赖理论计算分析诊断结构的病害状况并不总是容易实现的,本文介绍一种依据基本振型的振动反应求局刚度的方法,简单,实用,实践中如果辅以调查,考察,类比,分析...,可作出更切合实际的可靠诊断,文中还介绍一些实例,有助于启迪,开拓动态监测的应用领域。 相似文献
172.
改进的钢筋混凝土结构双参数地震破坏模型 总被引:34,自引:4,他引:34
本文在分析现有结构地震破坏模型的基础下,提出了一种改进掇参数地震破坏模型。文中采用三线退化型恢复力模型对实际钢筋混凝土结构在实际地震作用下的变形与累积耗能,极限变形与极限滞回耗能进行了分析,通过模型计算的破损结果与实际在结果的对比,研究了模型参数,从而建立了钢筋混凝土结构的双参数地震破坏模型。 相似文献
173.
The mechanisms of finite brittle strain 总被引:1,自引:0,他引:1
174.
During an earthquake, buildings which are vulnerable to seismic loads will be damaged, resulting in property loss and the potential for casualties. To reduce loss of life and injury, the relationship between earthquake-induced building failure and injury severity and distribution needs to be clarified. To this end, a methodology and a series of data collection forms were developed to collect pertinent data for post-event analysis and to provide a basis for structural triage in the field shortly following an earthquake for search and rescue purposes. The forms were developed in four steps: (1) identifying the variables which affect the outcome of an occupant in a damaged building; (2) classifying the variables into three levels of priority for data collection; (3) designing the forms; and (4) applying the forms to damaged buildings from past earthquakes. These forms represent a significant departure from existing forms in that they consider both casualties and building damage jointly in a consistent format. This paper describes the first two steps of the development process; a companion paper outlines the latter components. 相似文献
175.
地震损失评估与数据库系统 总被引:5,自引:0,他引:5
1989年10月大同-阳高地震后,国家地震局首次组织有关人员进行了震害评估,为政府进行抗震救灾决策提供了科学依据;对加快灾区重建,减少地震损失起了重要作用。本文根据大同-阳高地震的评估经验和近期研究成果,提出了一个震害快速评估实用方法,介绍了震害评估计算程序(EDEP),并以实例说明程序的主要功能和使用方法。最后,为更快地评估地震损失,建议建立重点监测区震害评估数据库系统,并提出数据库系统的建立方法。 相似文献
176.
Cold seep deposits of Beauvoisin (Oxfordian; southeastern France) and Marmorito (Miocene; northern Italy): microbially induced authigenic carbonates 总被引:12,自引:0,他引:12
J. Peckmann V. Thiel W. Michaelis P. Clari C. Gaillard L. Martire J. Reitner 《International Journal of Earth Sciences》1999,88(1):60-75
The relation of two well-known ancient carbonate deposits to hydrocarbon seepage was confirmed by this study. Archaea are
found to be associated with the formation of Oxfordian seep carbonates from Beauvoisin and with a Miocene limestone from Marmorito
("tube-worm limestone"). Carbonates formed due to a mediation by archaea exhibit extremely positive or extremely negative
δ13Ccarbonate values, respectively. Highly positive values (+15‰) reflect the use of 13C-enriched CO2 produced by methanogenesis. Low δ13C values of the Marmorito carbonates (–30‰) indicate the oxidation of seepage-derived hydrocarbons. Likewise, the δ13C content of specific tail-to-tail linked isoprenoids, biomarkers for archaea, was found to be strikingly depleted in these
samples (as low as –115‰). The isotopic signatures corroborate that archaea were involved in the cycling of seepage-derived
organic carbon at the ancient localities. Another Miocene limestone ("Marmorito limestone") shows a strong imprint of methanotrophic
bacteria as indicated by δ13C values of carbonate as low as –40‰ and biomarker evidence. Epifluorescence microscopy and field-emission scanning electron
microscopy revealed that bacterial biofilms were involved in carbonate aggregation. In addition to lucinid bivalves previously
reported from both localities, we infer that sponges from Beauvoisin and tube worms from Marmorito depended on chemosynthesis
as well. Low δ13C values of nodules related to sponge taphonomy (–27‰) indicate that sponges might have been linked to an enhanced hydrocarbon
oxidation. Tube worm fossils from Marmorito closely resemble chemosynthetic pogonophoran tube worms from Recent cold seeps
and are embedded in isotopically light carbonate (δ13C –30‰).
Received: 13 October 1998 / Accepted: 5 February 1999 相似文献
177.
Heidi Kreibich Veit Blauhut Jeroen C. J. H. Aerts Laurens M. Bouwer Henny A. J. Van Lanen Alfonso Mejia 《水文科学杂志》2020,65(3):491-494
ABSTRACTWe thank the authors, Brunella Bonaccorso and Karsten Arnbjerg-Nielsen for their constructive contributions to the discussion about the attribution of changes in drought and flood impacts. We appreciate that they support our opinion, but in particular their additional new ideas on how to better understand changes in impacts. It is great that they challenge us to think a step further on how to foster the collection of long time series of data and how to use these to model and project changes. Here, we elaborate on the possibility to collect time series of data on hazard, exposure, vulnerability and impacts and how these could be used to improve e.g. socio-hydrological models for the development of future risk scenarios. 相似文献
178.
以茶叶萌芽至展叶期寒冻害为突破口,利用1987—2016年福建省泉州市安溪县17个自动气象站2—4月的逐日气象数据及安溪各茶树种植区产量数据,确定茶叶寒冻害的天气指数保险气象指标,分析日极端最低气温与茶叶减产率的关系,建立了茶叶寒冻害指数模型。计算安溪不同区域茶叶种植区不同等级寒冻害的发生概率,应用纯保费率方法厘定了保险费率,并根据福建省政策性农业保险的实际情况,制定茶叶不同区域种植区寒冻害指数保险触发条件、赔付标准,设计了安溪县茶叶寒冻害天气指数保险合同。设计的茶叶寒冻害天气指数保险产品以客观气象数据作为定损依据,可以为茶农提供一种有效的风险转嫁方式,也为保险公司增加新险种提供了技术支撑。 相似文献
179.
地震速报参数不确定性的应急灾害损失快速评估模型 总被引:7,自引:0,他引:7
本文针对目前地震应急灾害损失快速评估中存在的问题,建立了考虑地震速报参数不确定性的灾害损失快速评估模型。并利用1990年来全国的81组速报震中与宏观震中数据。得到速报震中与宏观震中偏差的概率分布经验参数。 相似文献
180.