A multiphase approach to the stability analysis of reinforced earth structures accounting for a soil–strip failure condition

A multiphase model, developed in the context of elastoplasticity, is applied to the simulation and design of reinforced earth retaining structures. The main feature of this model is to combine the advantage of a homogenization approach, as regards its computational efficiency, with the ability to account for a specific failure condition at the interface between the soil and the reinforcing strips, which may have a decisive influence on the behavior of the structure. A particular emphasis is put on the stability analysis of this kind of reinforced soil structures, formulated within the framework of the yield design theory. Making use of a generalized rigid block failure mechanism, the stability of a reinforced earth retaining wall is investigated by means of the kinematic approach, leading to upper bound estimates for the stability factor of the structure, which are then favorably compared with the results of an elastoplastic analysis. Special attention is paid to assessing in a quantitative way how a specific soil–strip failure condition affects the stability of the reinforced earth structure as a whole.     

<国际地震动态>创刊30周年的回顾

在新世纪第一年的 5月迎来了《国际地震动态》创刊 30周年纪念。“30而立”一般泛指人到 30岁左右日臻成熟或在事业上取得初步成就 ,而对于一个已创办了 30年的刊物来说似也具有较为特殊的意义。作为本刊的创刊主编 ,此刻抚今追昔 ,不胜感慨 ,略作些许回顾 ,愿与本刊新老读者共飨。 1　本刊的历史沿革首先在此赘述几句 ,本人在文革前一直在外事单位工作 ,其中工作之一是先后主持编辑出版过英文周刊《北京动态》 (What's on inPeking)和参加编辑过中文周刊《国际文化动态“参考资料版”》;文革后调至地球物理研究所直至 1 987年 8月退休。来…     

Sedimentary Basin Analysis and Petroleum Potential of the Cretaceous Yuchon Group in Haenam Depression, SW Korea

IntroductionThe Haenam Depression filled with the LateCretaceous sediments and volcanics lies to the southwestern coast of Korea peninsula. The Cretaceousstrata (Yucheon Group) cover an area of ca. 200km2in the Haenam and Mokpo area. Regional geologicalsu…     

Pre-stack sea bottom detection and swell correction within an expected hyperbolic range for noisy high-resolution 8-channel airgun seismic data

Marine Geophysical Research - The Hugin Fracture, discovered in 2011, is an approximately 3.5&nbsp;km long seafloor fracture in the North Sea. This fracture was unexpected and, due to the...     

Influence of diesel fuel contamination on the electrical properties of unsaturated soil at a low frequency range of 100 Hz–10 MHz

In this study, the effect of diesel fuel contamination on the electrical properties of unsaturated soils was estimated in the low frequency ranges. For the soils having 5% water content, the electrical resistivity increased with the diesel fuel contents while the permittivity decreased at higher diesel contents. However, at 15% water content, the variation of electrical properties was not significant possibly because most of the electric currents should occur through the pore water. The linear relationship between the electrical resistivity and the diesel fuel contents in soil was developed at 5% water content, which implied that the electrical resistivity could be used to quantify the extent of diesel fuel contamination in soil. The results indicated that the electrical properties including the resistivity and the permittivity could give the reliable estimation on the diesel contamination with the low water content in soil and the frequency applied below 1 MHz.     

Phylogenetic,histological and age determination for investigation of non-native tropical black-lip pearl oyster, <Emphasis Type="Italic">Pinctada margaritifera</Emphasis>, settled in jeju,Korea

This study reports the first finding of tropical blacklip pearl (BLP) oyster, Pinctada margaritifera, in Korean waters. One BLP oyster was found and sampled from Beom-seom islet (33°13′N, 126°33′E) in the southern coast of Jeju Island, Korea in February, 2011. The taxonomic status of the specimen was confirmed by nucleotide sequences of the mitochondrial gene cytochrome oxidase I and 28S ribosomal DNA. Oxygen isotopic analysis (δ¹⁸O_sh) and histology were used to determine the specimen’s age and reproductive stage, which were 3.5 years and ripe male, respectively. This BLP oyster most likely originated in an area in the subtropics or tropics, such as the Okinawa archipelagic or Micronesian regions. We suggest that intensive monitoring surveys are necessary for confirming the northward expansion of BLP oyster in Korean waters in the near future.     

Flood modelling using the distributed event-based SCS-LR model in the Mediterranean Real Collobrier catchment

ABSTRACT

Event-based models are often used for flood prediction because they require fewer data than more complex models and account for a small number of parameters. We present the performance of such a model in simulating Mediterranean floods, with a focus on the initialization and on the impact of the rainfall uncertainties on the calibration of the model. The distributed event-based parsimonious Soil Conservation Service Lag-and-Route (SCS-LR) model was applied in the Real Collobrier catchment, France, which has a very high density of raingauges. The initial condition of the model was highly correlated with predictors, such as baseflow or soil water content. A reduction in the raingauge density can markedly change the calibration of the model. As the density of raingauges is generally low in most catchments, the uncertainties associated with rainfall measurement are thus expected either to mask the actual accuracy of the model, or to alter the model parameters.