scholarly journals OPTIMAL RADIUS OF KINEMATICALLY AFFECTED PILE INFLUENCED BY LOCAL NONLINEARITY IN COHESIVE SOIL

2008 ◽  
Vol 64 (2) ◽  
pp. 179-191
Author(s):  
Masato SAITOH
2019 ◽  
Vol 92 ◽  
pp. 01004
Author(s):  
Christopher Ibeh ◽  
Matteo Pedrotti ◽  
Alessandro Tarantino ◽  
Rebecca Lunn

The quality and reliability of cohesive soil laboratory test data can be significantlyaffected by sample disturbance during sampling or sample preparation. Sample disturbance may affect key design and modelling parameters such as stiffness, preconsolidation stress, compressibility and undrained shear strength, and ultimately determine particle mobilization and shear plane development. The use of X-ray computed tomography (X-CT) in the study of soil is restricted by the inverse relationship of specimen size and obtainable image resolution. This has led to the testing of miniature specimen sizes which are far less than conventional laboratory sample size in a bid to obtain high resolution images and detailed particle-scale soil properties; however, these miniature soil specimens are more prone to sample disturbance. In this work 2% muscovite was mixed with speswhite kaolin clay as a strain marker for use in X-CT. The clay soil sample was prepared from slurry and either consolidated using an oedometer or a gypsum mould. Specimens obtained from a 7 mm tube sampler were compared to lathe trimmed specimens with a diameter (Ø) of 7 mm. Results from X-CT imaging were used to study the influence of sampler type on specimen disturbance, by analysing the muscovite particle orientation of the obtained 3D images. The results show that; for samples subjected to large consolidation stress (>200kpa) lathe trimmed specimens may be subject to lesser disturbance compared to tube sampled specimens.


Author(s):  
Giovanni Tripepi ◽  
Mario Plebani ◽  
Giorgio Iervasi ◽  
Mercedes Gori ◽  
Daniela Leonardis ◽  
...  

Abstract Background Italy was the second country in the world, after China, to be hit by SARS-CoV-2 pandemic. The Italy’s experience teaches that steps to limit people’s movement by imposing “red zones” need to be put in place early by carefully identifying the cities to be included within these areas of quarantine. The assessment of the relationship between the distance from an established outbreak of SARS-CoV-2 infection with transmission-linked cases and mortality observed in other sites could provide useful information to identify the optimal radius of red zones. Methods We investigated the relationship between SARS-CoV-2 cases and the distance of each Italian province from the first outbreak of SARS-CoV-2 epidemic in Italy (the city of Lodi placed in the Lombardia region). In 38 provinces of Lombardia and neighboring regions, we performed a breakpoint analysis to identify the radius of the red zone around Lodi minimizing epidemic spread and mortality in neighboring cities. Results In all Italian provinces a non-linear relationship was found between SARS-CoV-2 cases and distance from Lodi. In an analysis including the provinces of Lombardia and neighboring regions, SARS-CoV-2 cases and mortality increased when the distance from Lodi reduced below 92 km and 140 km, respectively, and such relationships were amplified by ozone (O3) pollution. Conclusions The breakpoint analysis identifies the radius around the outbreak of Lodi minimizing the public health consequences of SARS-CoV-2 in neighboring cities. Such an approach can be useful to identify the red zones in future epidemics due to highly infective pathogens similar to SARS-CoV-2.


2021 ◽  
Vol 209 ◽  
pp. 106-124
Author(s):  
Kojo Atta Aikins ◽  
James B. Barr ◽  
Diogenes L. Antille ◽  
Mustafa Ucgul ◽  
Troy A. Jensen ◽  
...  

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