排序方式： 共有7条查询结果，搜索用时 46 毫秒
1
1.
Different Approaches for Simulating Brittle Failure in Two Hard Rock Mass Cases: A Parametric Study 总被引：2，自引：0，他引：2
Catrin Edelbro 《Rock Mechanics and Rock Engineering》2010,43(2):151-165
One of the aims of rock mechanics analysis is to predict fallouts in underground excavations. The objective of this paper
was to study the relative importance of different strength parameters and their significance on the simulation of brittle
failure and fallouts. This work was conducted as a parametric study, using numerical modelling and a number of approaches.
The results were compared with observed fallouts. More obvious and distinct shear bands could be observed with decreased element
sizes close to, and at, the boundary. The maximum shear strain was the most reliable indicator for fallout prediction. The
results of the (instantaneous) cohesion softening friction softening models were sensitive to changes of the peak strength
parameters and less sensitive to variations in residual parameters. The result from the cohesion-softening friction-hardening
(CSFH) model, when using a peak cohesion equal to the intact rock strength, best captured the observed rock behaviour. 相似文献
2.
Papathoma-Koehle Maria Promper Catrin Bojariu Roxana Cica Roxana Sik Andr&#;s Perge Kinga L&#;szl&#; Peter Czikora Erika Bal&#;zs Dumitrescu Alexandru Turcus Cosmin Birsan Marius-Victor Velea Liliana Glade Thomas 《Natural Hazards》2016,81(1):89-115
This paper reports on a quantitative estimation of the risk to residents at the toe of Mount Albino, a carbonatic relief covered by shallow deposits of pyroclastic soils, which threatens the municipality of Nocera Inferiore (southern Italy). The quantitative risk analysis (QRA) focuses on one type of mass transport phenomena typical for the context at hand, namely the hyperconcentrated flows. The methodological approach includes three main steps: hazard analysis, consequence analysis and risk estimation. Based on historical incident data, the hazard analysis makes use of a high-resolution digital terrain model and advanced models that incorporate relevant geological and geotechnical input data collected via in situ investigations and laboratory tests. The consequence analysis takes into account information on the exposed persons (age, gender) and their vulnerability. The estimated risk to life is calculated at the individual level (risk to the average and most exposed person). The reported procedure is one of the first QRA’s applications to instabilities which potentially affect natural slopes in Italy, and it was successfully used as technical basis for a public participatory process in Nocera Inferiore, designed and developed to support decisions about risk mitigation measures. 相似文献
3.
Natural Hazards - Existing research indicates that distinct human populations may prepare for, experience, and recover from wildfires in different ways. However, research that helps explain... 相似文献
4.
Catrin Schmidt 《中国勘察设计》2007,(3):65-65
有很多关于土地使用方面的工具，其中之一就是环境评价。环境评价是一个过程，即在做出项目决策的时候，要对这一项目可能对于环境产生的影响进行评价。从原则上来讲，环境评价是针对个体的项目进行的评估。 相似文献
5.
6.
Kettle holes are glacially created, small, shallow, depressional wetlands collecting their water from internal or closed catchments in young moraine landscapes. Their water body is defined by having a maximum of 1 ha in extent. Mostly they undergo a wet-dry circle. In North-East Germany, kettle holes are widely spread, mostly on arable land. They are characterised by large differences in hydroperiod (HP), size, shape and edge steepness. They also have a high potential for both, geomorphic structural diversity and biological species diversity. However, kettle holes are subject to pollution, drainage and structural reduction that result from intensive land use practices.Although kettle holes in Germany are protected by law, protection strategies are not specific enough with respect to the variability of kettle holes, especially of HP. Therefore, the study objective was to characterise hydrogeomorphic (HGM) kettle hole types to create a basis for a decision support system with regard to the selection of the type dependent conservation and management measures.In three agricultural landscapes in North-East Germany, geomorphological and hydrological variables of 268 kettle holes (HP, shore overflow tendency, depth, area, form, shore width and slope) as well as those of their catchments (area, wetland to catchment area ratio, relief) were investigated from 1993 to 2003. By statistical analysis of datasets of 144 kettle holes, 10 HGM kettle hole types were defined. The basic types are “silted fen type” and “open-water type”. Basic subtypes of the latter type are “storage type”, “shore overflow type” and “puddle type”. Differences in spreading of kettle hole types in dependency on landscape relief were found. 相似文献
7.
Many granites that occur in orogenic belts such as the Himalaya, the Hercynides or Caledonides are thought to result from anatexis of the lower parts of over-thickened thrust-stacked crustal units, just preceding termination of the orogenic cycle. Numerous Tertiary granitoids occur in the Rhodope Zone of northern Greece (and adjacent regions of Bulgaria), a belt regarded as an eastern extension of the Alpine System. These granites could also be regarded as syn- or late-tectonic crustal melts in that some have been emplaced as sheet-like bodies along major Alpine thrust planes, and show a strong marginal foliation parallel to the pervasive Alpine compressional fabrics. In detail, however, the geochemistry of the granitoids, their timing and relationships with country rocks, suggest they have been emplaced in an extensional regime that is related to the collapse of the Hellenic Orogen and, more particularly, to the crustal thinning that the Aegean region has suffered since the mid-Tertiary. Rather than being products of crustal thickening, it is suggested that their petrogenesis is related to the elevation of thermal gradients during the extensional phase, which initiated thermal breakdown of hydrous minerals in the lithosphere and lower crust that had existed metastably during compression and the subduction of cool ocean lithosphere beneath the region in the late Mesozoic-early Tertiary. 相似文献
1