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91.
Danny Arroyo Daniel García Mario Ordaz Mauricio Alexander Mora Shri Krishna Singh 《Journal of Seismology》2010,14(4):769-785
We derive strong ground-motion relations for horizontal components of pseudo-acceleration response spectra from Mexican interplate
earthquakes at rock sites (NEHRP B class) in the forearc region. The functional form is obtained from the analytical solution
of a circular finite-source model. For the regression analysis we use a recently proposed multivariate Bayesian technique.
The resulting model has similar accuracy as those models derived from regional and worldwide subduction-zone databases. However,
there are significant differences in the estimations computed from our model and other models. First, our results reveal that
attenuation in Mexico tends to be stronger than that of worldwide relations, especially for large events. Second, our model
predicts ground motions for large earthquakes at close distances to the source that are considerably larger than the estimations
of global models. Lack of data in this range makes it difficult to identify the most appropriate model for this scenario.
Nevertheless, according to the available data at the city of Acapulco, our model seems to estimate seismic hazard more adequately
than the other models. These new relations may be useful in computing seismic hazard for the Mexican forearc region, where
no similar equations had been yet proposed. 相似文献
92.
The paper presents an overview of the progress in research regarding seismic response of plan and vertically irregular building
structures. Three areas of research are surveyed. The first is the study of the effects of plan-irregularity by means of single-storey
and multi-storey building models. The second area encompasses passive control as a strategy to mitigate torsional effects,
by means of base isolation and other types of devices. Lastly, the third area concerns vertically irregular structures and
setback buildings. Although fewer papers have been published in this last area with respect to the former ones, this state-of-the-art
reports extensively on research efforts and progress into the seismic behaviour of irregular buildings in elevation to show
the growing interest among specialists in the field. 相似文献
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Hartmut H. Hellmer Monika Rhein Günther Heinemann Janna Abalichin Wafa Abouchami Oliver Baars Ulrich Cubasch Klaus Dethloff Lars Ebner Eberhard Fahrbach Martin Frank Gereon Gollan Richard J. Greatbatch Jens Grieger Vladimir M. Gryanik Micha Gryschka Judith Hauck Mario Hoppema Oliver Huhn Torsten Kanzow Boris P. Koch Gert König-Langlo Ulrike Langematz Gregor C. Leckebusch Christof Lüpkes Stephan Paul Annette Rinke Bjoern Rost Michiel Rutgers van der Loeff Michael Schröder Gunther Seckmeyer Torben Stichel Volker Strass Ralph Timmermann Scarlett Trimborn Uwe Ulbrich Celia Venchiarutti Ulrike Wacker Sascha Willmes Dieter Wolf-Gladrow 《Ocean Dynamics》2016,66(11):1379-1413
97.
Miriam Marzen Mario Kirchhoff Irene Marzolff Ali Aït Hssaine Johannes B. Ries 《地球表面变化过程与地形》2020,45(15):3808-3823
The endemic argan woodlands cover large parts of South Morocco and create a characteristic landscape with areas of sparsely vegetated and bare soil surfaces between single trees. This unique ecosystem has been under extensive agrosilvopastoral management for centuries and is now at risk of degradation caused by overgrazing and increasing scarcity and variability of rainfall. To investigate susceptibility to wind erosion, we conducted an experimental–empirical study including wind tunnel tests and a drone-generated digital elevation model and quantified wind-erodible material on five different associated surface types by means of sediment catchers. The highest emission flux was measured on freshly ploughed surfaces (1875 g m–2 h–1), while older ploughed areas with a re-established crust produced a much lower emission flux (795 g m–2 h–1). Extensive tillage may have been a sustainable practice for generations, but increasing drought and uncertainty of rainfall now lead to an acute risk of severe soil erosion and dust production. The typical crusted surfaces characterized by residual rock fragment accumulation and wash processes produced the second highest emission flux (1,354 g m–2 h–1). Material collected from tree-shaded areas (933 g m–2 h–1) was revealed to be a considerable source of organic material, possibly affecting substrate conditions positively on a larger regional scale. The lowest flux was measured on rock fragment-covered surfaces (301 g m–2 h–1). The data show that open argan woodland may be a considerable source for wind erosion and dust production, depending on surface characteristics strongly related to management. An adapted management must include the conservation of argan trees to offer a promising approach to prevent severe wind erosion and dust production and mitigate possible impacts of land-use change and climate change related shifts in wind and rainfall patterns. © 2020 The Authors. Earth Surface Processes and Landforms published by John Wiley & Sons Ltd 相似文献
98.
River restoration measures are becoming increasingly popular and are leading to dynamic river bed morphologies that in turn result in complex water level distributions in a river. Disconnected river branches, nonlinear longitudinal water level profiles and morphologically induced lateral water level gradients can evolve rapidly. The modeling of such river‐groundwater systems is of high practical relevance in order to assess the impact of restoration measures on the exchange flux between a river and groundwater or on the residence times between a river and a pumping well. However, the model input includes a proper definition of the river boundary condition, which requires a detailed spatial and temporal river water level distribution. In this study, we present two new methods to estimate river water level distributions that are based directly on measured data. Comparing generated time series of water levels with those obtained by a hydraulic model as a reference, the new methods proved to offer an accurate and faster alternative with a simpler implementation. 相似文献
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Bulletin of Earthquake Engineering - In past decades, multistory housing buildings have been constructed in high-seismic-risk regions in Latin America using thin reinforced concrete (RC) walls as... 相似文献