scholarly journals Random Characteristics of Hydraulic Gradient through Three-Dimensional Multilayer Embankment

2022 ◽  
Vol 2022 ◽  
pp. 1-8
Author(s):  
Xiaoming Zhao ◽  
Yulong Niu ◽  
Dongbin Cui ◽  
Mingming Hu
Keyword(s):  
Hydraulic Conductivity ◽  
Three Dimensional ◽  
Vertical Direction ◽  
Hydraulic Gradient ◽  
Deterministic Analysis ◽  
Soil Hydraulic Conductivity ◽  
The Monte Carlo Method ◽  
M 12 ◽  
Soil Hydraulic ◽  
Local Average

The distribution characteristics of hydraulic gradient in embankment are closely related to seepage failure. Seepage failures such as flowing soil and piping will lead to serious damage and even the overall failure of embankment. The hydraulic conductivity has strong spatial variability, which changes the distribution of hydraulic gradient in embankment and increases the difficulty for predicting the embankment seepage instability. In this study, the distribution of soil hydraulic conductivity in a section of Shijiu Lake embankment was obtained by the permeability test. Based on Local Average Subdivision technique, a three-dimensional multilayer random field of embankment hydraulic conductivity was generated. Then, the mean and standard deviation of overflow point height and hydraulic gradient were calculated by the Monte Carlo method, which combined the generated three-dimensional random model and the deterministic analysis method of seepage field. Finally, the coefficient of variation (COV) of hydraulic conductivity (0.1, 0.3, 0.5, 0.7, 1.0, 2.0, and 3.0), the fluctuation scale in vertical direction (3 m) and the fluctuation scale in horizontal plane (3 m, 6 m, 12 m, 24 m, 36 m, and 48 m) were selected respectively for analyzing the random characteristics of embankment overflow point height and hydraulic gradient under the influence of different COV and fluctuation scale of embankment soil hydraulic conductivity.

Libardi's method refinement for soil hydraulic conductivity measurement

Soil Research ◽  
2001 ◽  
Vol 39 (4) ◽  
pp. 851 ◽  
Author(s):  
P. L. Libardi ◽  
P. L. Libardi ◽  
K. Reichardt ◽  
K. Reichardt
Keyword(s):  
Hydraulic Conductivity ◽  
Water Content ◽  
Soil Water ◽  
Soil Water Content ◽  
Conductivity Measurement ◽  
Soil Surface ◽  
Hydraulic Gradient ◽  
Saturated Soil ◽  
Soil Hydraulic Conductivity ◽  
Soil Hydraulic

The method of Libardi to estimate soil hydraulic conductivity in the field, during the redistribution of soil water, is discussed and improved. It is shown that if the saturated soil water content is measured at the soil surface, values at any other depth can be calculated from the database used to compute hydraulic conductivity. Since the saturated soil water content is difficult to measure and critical to the establishment of the hydraulic conductivity functions, this is an important refinement of the method. It is also shown that the unit hydraulic gradient assumption, which is part of the methodology, does not introduce significant errors in the estimation of soil hydraulic conductivity.

Effect of Local Soil Hydraulic Conductivity Drop Using a Three-Dimensional Root Water Uptake Model

2008 ◽  
Vol 7 (3) ◽  
pp. 1089-1098 ◽  
Author(s):  
Tom Schröder ◽  
Mathieu Javaux ◽  
Jan Vanderborght ◽  
Bernd Körfgen ◽  
Harry Vereecken
Keyword(s):  
Hydraulic Conductivity ◽  
Water Uptake ◽  
Three Dimensional ◽  
Root Water Uptake ◽  
Soil Hydraulic Conductivity ◽  
Local Soil ◽  
Soil Hydraulic

Simplified estimation of unsaturated soil hydraulic conductivity using bulk electrical conductivity and particle size distribution

Soil Research ◽  
2013 ◽  
Vol 51 (1) ◽  
pp. 23 ◽  
Author(s):  
Mohammad Reza Neyshabouri ◽  
Mehdi Rahmati ◽  
Claude Doussan ◽  
Boshra Behroozinezhad
Keyword(s):  
Electrical Conductivity ◽  
Particle Size ◽  
Hydraulic Conductivity ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Unsaturated Soil ◽  
Soil Core ◽  
Soil Hydraulic Conductivity ◽  
Core Samples ◽  
Soil Hydraulic

Unsaturated soil hydraulic conductivity K is a fundamental transfer property of soil but its measurement is costly, difficult, and time-consuming due to its large variations with water content (θ) or matric potential (h). Recently, C. Doussan and S. Ruy proposed a method/model using measurements of the electrical conductivity of soil core samples to predict K(h). This method requires the measurement or the setting of a range of matric potentials h in the core samples—a possible lengthy process requiring specialised devices. To avoid h estimation, we propose to simplify that method by introducing the particle-size distribution (PSD) of the soil as a proxy for soil pore diameters and matric potentials, with the Arya and Paris (AP) model. Tests of this simplified model (SM) with laboratory data on a broad range of soils and using the AP model with available, previously defined parameters showed that the accuracy was lower for the SM than for the original model (DR) in predicting K (RMSE of logK = 1.10 for SM v. 0.30 for DR; K in m s–1). However, accuracy was increased for SM when considering coarse- and medium-textured soils only (RMSE of logK = 0.61 for SM v. 0.26 for DR). Further tests with 51 soils from the UNSODA database and our own measurements, with estimated electrical properties, confirmed good agreement of the SM for coarse–medium-textured soils (<35–40% clay). For these textures, the SM also performed well compared with the van Genuchten–Mualem model. Error analysis of SM results and fitting of the AP parameter showed that most of the error for fine-textured soils came from poorer adequacy of the AP model’s previously defined parameters for defining the water retention curve, whereas this was much less so for coarse-textured soils. The SM, using readily accessible soil data, could be a relatively straightforward way to estimate, in situ or in the laboratory, K(h) for coarse–medium-textured soils. This requires, however, a prior check of the predictive efficacy of the AP model for the specific soil investigated, in particular for fine-textured/structured soils and when using previously defined AP parameters.

Simple Field Methods for Estimating Soil Hydraulic Conductivity

1980 ◽  
Vol 44 (1) ◽  
pp. 3-7 ◽  
Author(s):  
P. L. Libardi ◽  
K. Reichardt ◽  
D. R. Nielsen ◽  
J. W. Biggar
Keyword(s):  
Hydraulic Conductivity ◽  
Field Methods ◽  
Soil Hydraulic Conductivity ◽  
Soil Hydraulic

Changes in soil hydraulic conductivity after prescribed fires in Mediterranean pine forests

2019 ◽  
Vol 232 ◽  
pp. 1021-1027 ◽  
Author(s):  
P.A. Plaza-Álvarez ◽  
M.E. Lucas-Borja ◽  
J. Sagra ◽  
D.A. Zema ◽  
J. González-Romero ◽  
...  
Keyword(s):  
Hydraulic Conductivity ◽  
Pine Forests ◽  
Prescribed Fires ◽  
Soil Hydraulic Conductivity ◽  
Soil Hydraulic ◽  
Mediterranean Pine

scholarly journals Effect of the dewatering on the surrounding terrains during the construction of Metrostation 9-III of the Sofia Metropoliten

2021 ◽  
Vol 82 (3) ◽  
pp. 207-209
Author(s):  
Ina Bojinova-Popova
Keyword(s):  
Hydraulic Conductivity ◽  
Deformation Modulus ◽  
Soil Deformation ◽  
Soil Hydraulic Conductivity ◽  
Soil Hydraulic

The international practice often faces significant settlements of terrains and structures due to dewatering. This study presents of the dewatering impact during the construction of Metrostation 9-III from the Sofia Metropoliten on the surrounding terrains and buildings. The subsidences are quantified for specific values of the soil deformation modulus and varying values of the soil hydraulic conductivity.

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