Analysis of the effects of the partial saturation on the Adige river embankment stability

Flooding is a worldwide phenomenon. Over the last few decades the world has experienced a rising number of devastating flood events and the trend in such natural disasters is increasing. Furthermore, escalations in both the probability and magnitude of flood hazards are expected as a result of climate change. Flood defence embankments are one of the major flood defence measures and stability assessment for these structures is therefore a very important process. Traditional deterministic approaches to stability analysis do not allow taking into account and quantifying the uncertainties in soil characterisation. For this reason they may not be sufficient to capture the failure of flood embankments. The paper presents a probabilistic approach for the stability analysis of flood embankments taking into account the probabilistic distribution of soil hydro-mechanical properties. The approach is validated against the failure case study of the Adige river embankment in Italy, by comparing the probability of failure of two sections, within and outside the failure segment respectively.

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Field Distribution of Strongly Excited Magnetic Lenses

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100114323 ◽

1975 ◽

Vol 33 ◽

pp. 140-141

Author(s):

M. Strojnik

Keyword(s):

Flux Density ◽

Field Distribution ◽

Optical Axis ◽

Operating Point ◽

Pole Piece ◽

Partial Saturation ◽

Axial Flux ◽

The Stability

Magnetic lenses operating in partial saturation offer two advantages in HVEM: they exhibit small cs and cc and their power depends little on the excitation IN. Curve H, Fig. 1, shows that the maximal axial flux density Bz max of one of the lenses investigated changes between points (3) and (4) by 5% as the excitation varies by 40%. Consequently, the designer can relax the requirements concerning the stability of the lens current supplies. Saturated lenses, however, can only be used if (i) unwanted fields along the optical axis can be controlled, (ii) 'wobbling' of the optical axis due to inhomogeneous saturation around the pole piece faces is prevented, (iii) ample ampere-turns can be squeezed into the space available, and (iv) the lens operating point covers a sufficient range of accelerating voltages.

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Assessing Persistence of Entrapped Gas for Induced Partial Saturation

Journal of Geotechnical and Geoenvironmental Engineering ◽

10.1061/(asce)gt.1943-5606.0002477 ◽

2021 ◽

Vol 147 (3) ◽

pp. 04020184

Author(s):

Babak Mahmoodi ◽

Aaron Gallant

Keyword(s):

Partial Saturation ◽

Induced Partial Saturation

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Evaluation of Bed Depth Reduction, Media Change, and Partial Saturation as Combined Strategies to Modify in Vertical Treatment Wetlands

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18094842 ◽

2021 ◽

Vol 18 (9) ◽

pp. 4842

Author(s):

Ismael Vera-Puerto ◽

Hugo Valdés ◽

Christian Correa ◽

Valeria Perez ◽

Roberto Gomez ◽

...

Keyword(s):

Natural Zeolite ◽

Domestic Wastewater ◽

Bottom Layer ◽

Treatment Wetlands ◽

Positive Development ◽

Experimental Plant ◽

Partial Saturation ◽

Treatment Wetland ◽

Media Change ◽

Depth Reduction

The aim of this work was to evaluate the performance of vertical subsurface flow treatment wetlands (VSSF TWs) for treating rural domestic wastewater when strategies such as bed depth reduction and media change are used in combination with bottom saturation. Two treatment wetland systems were implemented: normal (VF-N), with a bed depth of 1.0 m, and modified (VF-M), with a bed depth of 0.5 m and a bottom layer of natural zeolite. Schoenoplectus californicus was used as experimental plant. These two treatment systems were operated at a hydraulic loading rate of 120 mm/d in two phases. Phase I did not use bottom saturation, while Phase II involved a bottom saturation of the zeolite layer of the VF-M system. The results show that bed depth reduction did not have a significant effect (p > 0.05) in terms of organic matter, solids, and ammonium removal. Conversely, it had a significant influence (p < 0.05) on phosphate as well as a negative effect on pathogen removal. This influence could be explained by initial media capacity for phosphorus removal and filtration importance in the case of pathogens. Partial saturation only had a positive influence on total nitrogen removal. The addition of a bottom layer of natural zeolite showed no positive effect on nutrient removal. The plant showed adaptation and positive development in both VF-N and VF-M. The water balance showed that water loss was not influenced by bed depth reduction. Therefore, according to the previous results, a combination of the proposal modifications to VSSF TWs can be introduced for treating rural domestic wastewater.

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Key issues on seepage analysis in mountain river embankment

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/189/5/052041 ◽

2018 ◽

Vol 189 ◽

pp. 052041

Author(s):

Wenjia Tang ◽

Jiamin Hong ◽

Xinzhou Huang ◽

Jian Huang

Keyword(s):

Mountain River ◽

Seepage Analysis ◽

Key Issues ◽

River Embankment

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Experimental observation on laterally loaded pile in unsaturated silty soil

Canadian Geotechnical Journal ◽

10.1139/cgj-2018-0322 ◽

2019 ◽

Vol 56 (11) ◽

pp. 1545-1556 ◽

Cited By ~ 4

Author(s):

L.M. Lalicata ◽

A. Desideri ◽

F. Casini ◽

L. Thorel

Keyword(s):

Water Table ◽

Ground Surface ◽

Bending Moment ◽

Data Interpretation ◽

Partial Saturation ◽

Laterally Loaded Piles ◽

Silty Soil ◽

Centrifuge Tests ◽

Surface Data ◽

Laterally Loaded

An experimental study was carried out to investigate the effects of soil partial saturation on the behaviour of laterally loaded piles. The proposed study was conducted by means of centrifuge tests at 100g, where a single vertical pile was subjected to a combination of static horizontal load and bending moment. The study was conducted on a silty soil characterized with laboratory testing under saturated and unsaturated conditions. During flight, two different positions of water table were explored. The influence of density was investigated by compacting the sample with two different void ratios. Finally, the effects of a variation of saturation degree on the pile response under loading were studied by raising the water table to the ground surface. Data interpretation allows drawing different considerations on the effects of partial saturation on the behaviour of laterally loaded piles. As expected, compared to saturated soils, partial saturation always leads to a stiffer and resistant response of the system. However, the depth of the maximum bending moment is related to the position of the water table and the bounding effects induced by partial saturation appear to be more important for loose soils.

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