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11.
Vairaktaris Emmanouil Theocharis Alexandros I. Dafalias Yannis F. 《Acta Geotechnica》2020,15(3):681-694
Acta Geotechnica - Soil fabric anisotropy can be quantitatively assessed by means of fabric tensors introduced as internal variables in constitutive models and defined by unit vectors along the... 相似文献
12.
According to Litwiniszyn's theory, subsidence over a yielding underground geo‐structure is seen as a stochastic (Markov) process. This theory leads to a single, linear parabolic differential equation of diffusion–convection type (D–C equation) in the plane‐field of displacements. If the boundary conditions for the governing D–C equation are prescribed along the shear bands, i.e. at ‘moving’ boundaries—it has been observed from small‐scale model experiments that the subsiding process is always confined between a set of inclined shear bands—then the resulting equation is nonlinear. The inverse problem for this nonlinear equation, i.e. the problem of determining the base displacement using the surface subsidence as ‘initial’ condition, is ill‐posed and estimation of the base displacement from a given surface subsidence profile is not possible. In the present paper the domain of integration of the governing D–C equation is fixed (and bounded)—the boundaries are not evolving. Hence, the governing equation remains linear parabolic. The advantage is that this linear differential equation admits an analytical solution, under the trap‐door mechanism assumption, that enables a direct solution to the inverse problem. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
13.
Al Heib Marwan Zevgolis Ioannis E. Theocharis Alexandros I. Koukouzas Nikolaos C. Coccia Stella 《Geotechnical and Geological Engineering》2022,40(3):1307-1321
Geotechnical and Geological Engineering - Mining operations can drastically affect the stability of nearby areas. A representative case for this has been the Mavropigi mine, a part of an open-pit... 相似文献
14.
Deliveris Alexandros V. Theocharis Alexandros I. Koukouzas Nikolaos C. Zevgolis Ioannis E. 《Geotechnical and Geological Engineering》2022,40(8):4023-4039
Geotechnical and Geological Engineering - Rainfall leads to the deterioration of slope stability conditions, while intense rainfall has been commonly associated with landslides on natural or... 相似文献
15.
M. N. Tsimplis A. F. Velegrakis P. Drakopoulos A. Theocharis M. B. Collins 《Progress in Oceanography》1999,44(4):2045
A simple hydraulic model is used to estimate the deep water fluxes of Cretan Deep Water (CDW), through the Cretan Arc Straits and into the Eastern Mediterranean Basins. The input to the model consists of the height of the deep water reservoir above sill depth and its density difference from the overlying water masses. Data from four hydrographic cruises, which took place in 1995, 1991 and 1987, are used to estimate the depth of the reservoir above the sill and the density difference. The results show a significant CDW outflow of 0.75×106 m3 s−1 in early 1995. The outflow of CDW through Kassos Strait, in the east, is 0.53×106 m3 s−1, while 0.22×106 m3 s−1 outflows through the Antikithira Strait in the west. The model results agree with fluxes estimated from current meter observations.The CDW outflow has been neither steady nor uniform during the period 1987–95. In the Kassos Strait, the outflow commenced in 1987 and increased rapidly until 1991; since then, it appears to have stabilised. In the Antikithira Strait, in contrast, the outflow has increased steadily since 1987. Such modifications in the CDW outflow are associated with changes in its hydrographic characteristics. The salinity of CDW increased constantly, by approximately 0.1, between 1987 and 1995 while its temperature warmed, between 1987 and 1991, and then cooled. 相似文献
16.
Ana Rita Carrasco Theocharis Plomaritis Johan Reyns Óscar Ferreira Dano Roelvink 《Ocean Dynamics》2018,68(9):1121-1139
This study evaluates the patterns and effects of relative sea-level rise on the tidal circulation of the basin of the Ria Formosa coastal lagoon using a process-based model that is solved on an unstructured mesh. To predict the changes in the lagoon tidal circulation in the year 2100, the model is forced by tides and a static sea level. The bathymetry and the basin geometry are updated in response to sea-level rise for three morphological response scenarios: no bed updating, barrier island rollover, and basin infilling. Model results indicate that sea-level rise (SLR) will change the baseline current velocity patterns inside the lagoon over the ~100-year study period, due to a strong reduction in the area of the intertidal basin. The basin infilling scenario is associated with the most important adjustments of the tidal circulation (i.e., increases in the flood velocities and delays in the ebb tide), together with an increase in the cumulative discharges of the tidal inlets. Under sea-level rise and in the basin infilling scenario, the salt marshes and tidal flats experience increases in the tidal range and current asymmetry. Basin infilling changes the sediment flushing capacity of the lagoon, leading to the attenuation of the flood dominance in the main inlet and the strengthening of the flood dominance in the two secondary inlets. The predictions resulting from these scenarios provide very useful information on the long-term evolution of similar coastal lagoons that experience varying degrees of SLR. This study highlights the need for research focusing on the quantification of the physical and socio-economic impacts of SLR on lagoon systems, thus enabling the development of effective adaptation strategies. 相似文献