Article
Engineering, Geological
Hardy Yide Kek, Yutao Pan, Yannick Choy Hing Ng, Fook Hou Lee
Summary: This study presents a framework for modeling random permeability variation in cement-admixed soil and demonstrates the significant influence of spatial variability on the overall consolidation rate, especially when soil strength variability is high. Results suggest that the prescribed scales of fluctuation play a key role in the overall consolidation rates, with horizontal layering potentially causing stagnation in pore pressure dissipation.
Article
Engineering, Geological
Moozhikkal Raheena, Retnamony G. Robinson
Summary: This study introduces a faster and more complete consolidation testing procedure using the inflection point method, which can obtain the void ratio-consolidation curve and coefficient of consolidation of soils in a shorter time. The validity of this method is verified through tests on different soil samples.
Article
Environmental Sciences
Shaoyi Wang, Jiawei Wu, Peifu Cai, Cong Chen, Shenghua Ye, Jianqiang Xu, Liang Chen, Xiaoyong Luo, Jun Wei
Summary: The vertical barrier technique is an ideal option for controlling site contamination. A numerical model was used to investigate the groundwater flow and contaminant transport coupling effect in a vertical cut-off wall with depth-dependent permeability. The results showed that a variable permeability barrier can significantly reduce breakthrough time compared to a fixed permeability barrier. The presence of the barrier increased the contaminant concentration inside the wall and shallow leakage occurred where horizontal migration was dominated by advection. Installing high-density polyethylene (HDPE) membranes reduced the shallow convective effect by up to 90% due to a decrease in pore-water pressure. Reinforcing the vertical barrier with HDPE membranes effectively prevents shallow leakage caused by heterogeneity.
WATER AND ENVIRONMENT JOURNAL
(2023)
Article
Engineering, Geological
Peng Wang, XiaoTian Yang, Jian Zhang, Xueyan Ge
Summary: This study investigated the clogging of a soil pile in the vacuum preloading of dredged soil combined with a prefabricated vertical drain (PVD) through laboratory model tests and analytical modeling. The formation of a soil pile was clarified by the variation in water content and permeability of soil around the PVD. Seepage and consolidation tests showed that the clogging effect slowed down the drainage of pore water rather than stopping it completely. An analytical model considering the clogging effect and the varying permeability and compressibility of soil was established. Based on a comparison with existing results, an empirical linear relationship was developed to estimate the permeability and scale of a soil pile in vacuum-assisted soil consolidation. The study found that a soil pile with lower permeability or larger diameter resulted in more serious clogging effects on soil consolidation, and the development of the clogging effect decreased as the soil pile extended.
PROCEEDINGS OF THE INSTITUTION OF CIVIL ENGINEERS-GEOTECHNICAL ENGINEERING
(2022)
Article
Engineering, Geological
Deryck Chan, Gopal Madabhushi, Giulia Viggiani, Michael Williamson, Yu Sheng Hsu
Summary: This study investigates the problem of long-term basement heave in clay areas through centrifuge tests. The results show that stiff basements generate large swell pressures and bending stresses, while flexible basements experience significant differential heave. The prediction of high heave pressures is a self-fulfilling prophecy.
Article
Engineering, Geological
Ling-Ling Zeng, Yu-Feng Gao, Zhen-Shun Hong
Summary: The study investigated the relationship between shear strength and compressibility of different types of clays with varying water contents. It proposed quantitative expressions to determine this relationship and normalized compression curves using an intrinsic compression framework.
Article
Engineering, Geological
Shubhrajit Maitra, Yinghui Tian, Mark J. Cassidy
Summary: This study investigates the installation of drag-in plate anchors using advanced large-deformation finite-element (LDFE) analysis and introduces a new modelling technique. The findings suggest that plasticity and analytical approaches may not be conservative in shallow conditions and highlight the importance of considering soil remoulding. These results provide insights for offshore engineers when estimating a drag anchor installation trajectory and holding capacity.
Article
Energy & Fuels
Bertrand Francois, Gilles Corda
Summary: This article investigates the kinetics of one-dimensional self-weight consolidation of dredged mud and finds that it is influenced by the permeability, compressibility, height, and drainage conditions of the mud. The study proposes two original experiments to determine the constitutive relations governing the consolidation process and monitors the settlement and excess pore water pressure during tests. In addition, a finite difference method is used to evaluate the ability of the constitutive relations to reproduce the consolidation kinetics. The article also performs sensitivity analysis on the constitutive relations and concludes that the draining sand at the base has an insignificant role on the consolidation speed.
GEOMECHANICS FOR ENERGY AND THE ENVIRONMENT
(2022)
Article
Geosciences, Multidisciplinary
Pin Zhang, Zhen-Yu Yin, Yin-Fu Jin, Tommy H. T. Chan, Fu-Ping Gao
Summary: This study proposes a novel modeling approach using machine learning techniques to predict the compression index C c in geotechnical design, showing that machine learning models outperform traditional empirical prediction formulations. Among the tested machine learning algorithms, random forest and back-propagation neural network models are recommended for predicting C c under different conditions.
GEOSCIENCE FRONTIERS
(2021)
Article
Engineering, Marine
Yinghui Tian, Jie Ren, Tao Zhou, Maozhu Peng, Mark J. Cassidy
Summary: In geotechnical engineering, numerical modelling of structure-soil interaction is a fundamental and challenging topic. A versatile interface that accounts for contributions from the soil skeleton and pore fluid is needed. This paper presents two coupled hydro-mechanical interfaces that can be used to model uplift problems.
Article
Chemistry, Physical
Luca Sorrentino, Sandro Turchetta, Gianluca Parodo, Roberta Papa, Elisa Toto, Maria Gabriella Santonicola, Susanna Laurenzi
Summary: This work aims to investigate the potential and limitations of composite materials made of flax fiber and bio-based epoxy resin, and develop process parameters and a numerical model for producing green laminates through the RIFT process. Compressibility tests and permeability tests were conducted to evaluate the behavior of commercial flax woven under vacuum bag and the necessary permeability curves for numerical analysis of the infusion process. The results, compared with a petroleum-based epoxy system, demonstrate the potential and critical use of bio-based resins for infusion processes.
Article
Engineering, Environmental
Yang Zhou, Fang Xu
Summary: This study investigates the consolidation behavior of a two-soil-layer deposit through experiments and numerical analysis, revealing that the average degree of consolidation defined by excess pore water pressure is generally lower than that defined by settlement. A new index is introduced to quantify the difference, and a method is proposed to evaluate the consolidation condition of a two-soil-layer deposit using this index, showing satisfactory validity in tests.
BULLETIN OF ENGINEERING GEOLOGY AND THE ENVIRONMENT
(2022)
Article
Engineering, Geological
Chen Wang, Bipul Hawlader, Didier Perret, Kenichi Soga
Summary: In this study, flowslides and spreads in sensitive clays were simulated using a Eulerian-based large-deformation finite-element method. A strain-rate-dependent undrained shear strength model was used to consider the strain rate effects on liquefied clay. The rate of increase in undrained shear strength with depth in flowslides reduces the depth of subsequent slides, leading to a smaller retrogression distance. The ratio of horizontal to vertical stress, resistance to downslope movement, soil brittleness, and slope steepness changes the failure pattern from flowslides to spreads.
Article
Engineering, Environmental
Ngoc Ha Hoang, Anh My Chu, Kim Thai Thi Nguyen, Chi Hieu Le
Summary: This paper presents a novel mathematical modelling for simulating the spread of heavy metals in soil layers in MSW landfills. By deriving a governing equation and using a Finite Element Method (FEM) based algorithm, the variation of pollutants concentrations can be effectively analyzed. The applicability and advantages of this method are demonstrated through a case study with soil samples collected from an actual MSW landfill.
ENVIRONMENTAL ENGINEERING RESEARCH
(2022)
Article
Engineering, Petroleum
Ivan C. Aldana Gallego, Laura P. Santos, I. Yucel Akkutlu
Summary: A new laboratory method is introduced to predict sample pore volume, pore compressibility, and effective stress coefficient simultaneously for fluid storage capacity predictions under different stresses. The method involves two stages of gas uptake and pressure-volume measurements under changing pressures. The model is validated using a reference pore volume and can be applied to various rock samples such as sandstone, shale, and carbonate.
Article
Engineering, Geological
Max Wiebicke, Edward Ando, Gioacchino Viggiani, Ivo Herle
Article
Computer Science, Interdisciplinary Applications
X. S. Shi, Jiayan Nie, Jidong Zhao, Yufeng Gao
COMPUTERS AND GEOTECHNICS
(2020)
Article
Engineering, Geological
X. S. Shi, Yufeng Gao, Jianwen Ding
Summary: A novel compression model for sandy soils is proposed in this study, which takes into account the effects of initial void ratio and sand fraction on compression behavior by incorporating equivalent void ratio and a structure variable. The model is effective in reproducing the compression behavior of sandy soils with a wide range of initial void ratio and sand fraction.
ENGINEERING GEOLOGY
(2021)
Article
Engineering, Geological
X. S. Shi, Kai Liu, Jianhua Yin
Summary: The study focused on the mobilized shear strength of weathered rockfill materials and their applications in engineering practice. Through direct shear tests, a simple model based on mixture theory was proposed to reflect the evolution of stress ratio in the direct shearing process of gap-graded soils, providing theoretical and practical guidance.
Article
Engineering, Geological
X. S. Shi, Jidong Zhao, Yufeng Gao
Summary: This study presents a homogenization-based state-dependent model within the elastoplastic framework for describing the deformation behavior of gap-graded granular soils. The simulations reveal that the structure parameter in the model significantly impacts the mechanical properties of the soils, particularly the initial stiffness, peak shear strength, and residual shear strength.
INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS
(2021)
Article
Engineering, Geological
X. S. Shi, Kai Liu, Jianhua Yin
Summary: The study reveals that the overall shear strength of gap-graded soils is not solely dependent on the confining stress and coarse fraction, but also influenced by factors such as the shape of aggregates and the initial density of sand matrix. The partial contacts between aggregates and formation of sand bridges play significant roles in the overall behavior of gap-graded soils.
JOURNAL OF GEOTECHNICAL AND GEOENVIRONMENTAL ENGINEERING
(2021)
Article
Materials Science, Multidisciplinary
Selma Schmidt, Max Wiebicke, Ivo Herle
Summary: This study investigates the spatial and temporal distribution of fabric in a Hostun sand sample during triaxial compression tests, finding that the contact fabric variables precede void ratio changes.
Article
Engineering, Geological
Johannes Welsch, Ivo Herle
Summary: This study investigated the effects of suffosion on the behavior of soil. The results showed that increasing material density can reduce the material loss, deformation, and permeability caused by suffosion.
Article
Engineering, Geological
Yiwen Zeng, Xiusong Shi, Wenbo Chen, Weiqiang Feng
Summary: This paper proposes an explicit equivalent compression curve for clay-sand mixtures, incorporating the equivalent void ratio into the intrinsic compression model of the clay matrix. Experimental data show that the proposed stress versus equivalent void ratio relationship is simple yet effective in evaluating the compressibility of clay-sand mixtures with a wide range of sand fraction.
INTERNATIONAL JOURNAL OF GEOMECHANICS
(2023)
Article
Engineering, Geological
Yiwen Zeng, Xiusong Shi, Hao Xiong, Wenbo Chen, Xia Bian
Summary: Naturally sedimentary soils, such as marine clays, weathered residual soils, and glacial deposits, usually contain sand particles. The mechanical properties of these soils are dominated by the clay matrix and significantly affected by the interparticle structure. Previous research on sandy clay has been experimental or numerical, with little theoretical investigation on the reinforcing effect of coarse inclusions. This study proposes a constitutive model for sandy clays that incorporates the effect of sand content and successfully predicts the mechanical response of these soils.
INTERNATIONAL JOURNAL OF GEOMECHANICS
(2023)
Article
Engineering, Geological
Bozana Bacic, Ivo Herle
Summary: The build-up of pore water pressure during shearing in loose, saturated, coarse-grained soils can lead to a reduction in effective stresses and soil stiffness. A simplified cyclic shear test is presented to compare the sensitivity of different sands to density-dependent pore water pressure build-up.
Article
Engineering, Geological
Kornelia Nitzsche, Ivo Herle
Summary: The state of equilibrium of a slope is often evaluated using limit equilibrium methods, but it is often neglected that deformation in the shear zone must occur before reaching maximum shear resistance. The development of shear stress depends on factors such as soil density and hydraulic conditions, leading to non-uniform mobilization of shear resistance in the shear zone which can result in overestimation of slope stability. This report introduces a calculation method that couples slope stability development with shear strain in the shear zone.
Article
Engineering, Civil
Jamal Hleibieh, Ivo Herle
TRANSPORTATION INFRASTRUCTURE GEOTECHNOLOGY
(2020)
Article
Engineering, Geological
Christian Karcher, Silvia Imposimato, Ivo Herle
Proceedings Paper
Engineering, Geological
Ivo Herle, X. S. Shi, Christian Karcher
RECENT DEVELOPMENTS OF SOIL MECHANICS AND GEOTECHNICS IN THEORY AND PRACTICE
(2020)