Article
Engineering, Multidisciplinary
Shiyuan Yao, Yuchao Li, Shan Tong, Guannian Chen, Yunmin Chen
Summary: A numerical investigation was proposed to study the effect of chemical incompatibility of geosynthetic clay liner (GCL) on the barrier performance of a composite liner with hole defect. The results showed that the incompatibility of GCL significantly increased the leakage rate and flux through the composite liner. The area affected by incompatibility was located within 0.1 m from the center of the hole in the geomembrane (GMB). Consideration of GCL chemical incompatibility revealed that advection may dominate contaminant transport through GCL.
JOURNAL OF ZHEJIANG UNIVERSITY-SCIENCE A
(2023)
Article
Engineering, Geological
Huaxiang Yan, Haijian Xie, Hao Ding, Dandi Yang, Cong Chen, Yunmin Chen, Yun Chen
Summary: A composite liner system consisting of a geomembrane layer, a compacted clay layer, and an attenuation layer is widely used in landfills. Consolidation of the soil liner can have detrimental effects on contaminant breakthrough, particularly under relatively high stress caused by waste placement. This study develops a one-dimensional model to investigate the transport behavior of contaminants in the composite liner system considering consolidation. The results show that the volume compressibility coefficient in the attenuation layer and the thickness of the attenuation layer play important roles in controlling the consolidation induced effects.
INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS
(2022)
Article
Engineering, Geological
Shahin Ghazizadeh, Christopher A. Bareither
Summary: This study evaluated the shear behavior and failure mechanisms of composite systems comprised of a geosynthetic clay liner (GCL) and textured geomembrane (GMX). The peak critical shear strength of GCL/GMX composite systems increased with an increase in GMX spike density. The effect of geotextile type and mass per area more profoundly influenced peak critical shear strength at normal stress > 500 kPa.
GEOTEXTILES AND GEOMEMBRANES
(2021)
Article
Computer Science, Interdisciplinary Applications
Yu-Chao Li, Shi-Yuan Yao, Cheng Chen, Yun-Min Chen, Guan-Nian Chen, Ri -Hong Zhang
Summary: Geomembranes in landfill composite liners often have long defects, which can lead to underestimation of leakage rate. In this study, a new solution considering two-dimensional flow in the compacted clay liner (CCL) was proposed to predict the leakage rate through GMB/CCL composite liners. The proposed solution showed lower relative errors for leakage rate and wetted distance compared to the existing solution.
COMPUTERS AND GEOTECHNICS
(2023)
Article
Engineering, Geological
Genaro Gonzalo Carnero-Guzman, Abdelmalek Bouazza, Will P. Gates, R. Kerry Rowe, Rebecca McWatters
Summary: This study investigates the hydration and dehydration behavior of GCL under polar conditions in Antarctica, focusing on summer hydration and winter-summer dehydration cycles. The findings indicate that direct contact with groundwater leads to summer hydration, while low relative humidity environment causes dehydration, depending on the field conditions. Hydration from fine or coarse Antarctic soil is influenced by the original water content and grain size distribution of the subgrade soil, as well as the low relative humidity prevailing in Antarctica.
GEOTEXTILES AND GEOMEMBRANES
(2021)
Article
Engineering, Geological
Juan Hou, Rui Sun, Craig H. Benson
Summary: A hydrodynamic model was used to simulate the flow in an idealized geosynthetic clay liner (GCL) containing bentonite, and the results suggest that the hydraulic conductivity of GCLs decreases as the bentonite granules hydrate and swell, forming smaller intergranular flow paths. The model also indicates that greater granule swelling is required to achieve low hydraulic conductivity when the bentonite is comprised of larger granules or has a lower density. Furthermore, the model predicts that intergranular pores become extremely small as the hydraulic conductivity approaches 10-11 m/s.
GEOTEXTILES AND GEOMEMBRANES
(2023)
Article
Engineering, Geological
Hanrui Zhao, Kuo Tian
Summary: This study investigated the impact of polymer elution on the interface shear strength between a smooth geomembrane (GMB) and two types of bentonite-polymer (B-P) geosynthetic clay liners (GCLs) containing linear and crosslinked polymers. The results showed that polymer elution had a significant effect on the GMB/B-P GCL interface shear strength, especially at higher normal stress.
GEOTEXTILES AND GEOMEMBRANES
(2023)
Article
Engineering, Geological
Hakki O. Ozhan, Aykut Erkal
Summary: This paper investigates the occurrence of internal erosion and the variation of the permeability of geosynthetic clay liner (GCL) with respect to its geotextile component, polymer type and polymer amount added to its bentonite component, hydraulic head, and subgrade material. The results show that GCLs tested with woven geotextile experienced internal erosion at a hydraulic head of 10 m, and the treatment of Na CMC and PAM caused a significant decrease in permeability. The optimum polymer contents were found to be 2% Na CMC and 1% PAM.
GEOTEXTILES AND GEOMEMBRANES
(2023)
Article
Engineering, Geological
Mayu Tincopa, Abdelmalek Bouazza
Summary: This paper investigates the water retention curves of geosynthetic clay liners (GCLs) under non-uniform temperature-stress paths, finding that high vertical stresses lead to faster water uptake and low water viscosity caused by high temperatures accelerates water desorption during drying.
GEOTEXTILES AND GEOMEMBRANES
(2021)
Article
Environmental Sciences
Yu-Ling Yang, Xing-Yuan You, Jian-Nan Chen, Xian-Lei Fu, Yan-Jun Du
Summary: This study evaluated the potential application of a modified sodium bentonite geosynthetic clay liner (GCL) with acid-and-alkaline resistance for containing bauxite residue leachate. The hydraulic conductivity (k) of the GCL was quickly evaluated using different liquids, and the effects of various factors on the conductivity were analyzed. The results showed that the properties of the liquids significantly affected the hydraulic conductivity of the GCL, and further modifications are needed to meet the desired performance.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2022)
Article
Computer Science, Interdisciplinary Applications
Huaxiang Yan, Haijian Xie, Jiawei Wu, Hao Ding, Zhanhong Qiu, Zhilin Sun
Summary: An analytical model for transient contaminant transport in clay barriers under the combined effects of diffusion, adsorption, and consolidation processes has been developed. The model was validated using experimental results. The study found that the consolidation model with large displacement induces the shortest breakthrough time and contributes significantly to the contaminant flux.
COMPUTERS AND GEOTECHNICS
(2021)
Article
Engineering, Mechanical
Ting-Ting Li, Zhike Wang, Hao-Kai Peng, Xiayun Zhang, Liwei Wu, Ching-Wen Lou, Jia-Horng Lin
Summary: The study introduces glass-geogrid-reinforced GCLs for enhancing the mechanical properties and impermeability of liners, which can withstand toxic environments and high pressures. Additionally, the durability and heavy metal ions adsorption of these reinforced liners were explored under various simulated conditions.
JOURNAL OF SANDWICH STRUCTURES & MATERIALS
(2021)
Article
Engineering, Geological
Anna Norris, Neelufar Aghazamani, Joseph Scalia, Charles D. Shackelford
Summary: The hydraulic performance of geosynthetic clay liners (GCLs) enhanced with anionic polymers was evaluated under different conditions. The results showed that the hydraulic performance of GCLs to NaCl solution was better than that to CaCl2 solution. Dry sprinkling with poly(acrylic acid) (PA) generally provided the best hydraulic performance, while the viscosity grade of sodium carboxymethylcellulose (CMC) did not affect the hydraulic conductivity of the GCLs.
JOURNAL OF GEOTECHNICAL AND GEOENVIRONMENTAL ENGINEERING
(2022)
Article
Environmental Sciences
Hao Ding, Haijian Xie, Peifu Cai, Liang Wang, Huaxiang Yan, Aimin Jin, Yun Chen
Summary: This study develops alternative formulations for transient analytical modeling of organic contaminant transport in a composite of geosynthetic clay and attenuation layer system. The Laplace transform method is used to derive the solution. The proposed analytical frameworks are validated by benchmark tests and applied to evaluate various cases of organic contaminant transport.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2023)
Article
Engineering, Geological
Qin Li, Jiannan Chen, Craig H. Benson, Daoping Peng
Summary: The high ionic strength of porewater in red mud suppresses montmorillonite swelling, making geosynthetic clay liners (GCLs) too permeable for effective use in red mud disposal facilities. Bentonite-polymer composite GCLs (BPC GCLs) have been developed as more resilient lining materials, with hydraulic conductivity influenced by the leachate's chemical properties and polymer type.
GEOTEXTILES AND GEOMEMBRANES
(2021)
Letter
Engineering, Geological
Huaxiang Yan, Jiawei Wu, Haijian Xie, Hywel R. Thomas, Shijin Feng
INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS
(2020)
Article
Engineering, Geological
Majid Sedighi, Huaxiang Yan, Andrey P. Jivkov
Summary: This paper presents a non-local formulation for clay erosion, which combines clay swelling, particle detachment, and detached particle transport into a single modeling tool. The proposed model is validated against experimental data and shows excellent agreement. The results provide strong support for the applicability of the model to account for the hydro-chemical conditions of the eroding environment.
Article
Engineering, Geological
Huaxiang Yan, Haijian Xie, Shaoyi Wang, Zijing Zheng
Summary: Cutoff walls are used to isolate contaminants in geological environments. Various factors affect the transport of chemicals in cutoff walls and aquifers. Biodegradation and dimensionality play significant roles in the performance of barrier systems.
INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS
(2021)
Article
Engineering, Geological
Huaxiang Yan, Jiawei Wu, Hywel R. Thomas, Hao Ding, Liangtong Zhan, Haijian Xie
Summary: This study investigates the behavior of organic chemicals transport in landfill composite liner system. It was found that the triple liner under double drainage boundary condition performs better compared to the case under single drainage boundary condition. Additionally, GCL consolidation can increase the breakthrough time.
GEOTEXTILES AND GEOMEMBRANES
(2021)
Article
Computer Science, Interdisciplinary Applications
Huaxiang Yan, Haijian Xie, Jiawei Wu, Hao Ding, Zhanhong Qiu, Zhilin Sun
Summary: An analytical model for transient contaminant transport in clay barriers under the combined effects of diffusion, adsorption, and consolidation processes has been developed. The model was validated using experimental results. The study found that the consolidation model with large displacement induces the shortest breakthrough time and contributes significantly to the contaminant flux.
COMPUTERS AND GEOTECHNICS
(2021)
Article
Engineering, Geological
Huaxiang Yan, Majid Sedighi, Andrey Jivkov
Summary: This study investigates the erosion of clay buffer caused by interactions with groundwater and develops predictive models for the process. Experimental results show significant effects of water flowrate and chemistry on erosion rate, with further investigation needed for ionic concentrations below 1 mM.
ENGINEERING GEOLOGY
(2021)
Article
Environmental Sciences
Haijian Xie, Hao Ding, Huaxiang Yan, Dandi Yang, Zhanghua Lou, Zhanhong Qiu, Yun Chen
Summary: This study presents an analytical model to investigate the effects of cracks on the migration of organic contaminants in a composite liner system. The results show that the presence of cracks significantly affects the breakthrough curve and bottom concentration of contaminants. Increasing the adsorption factor and degradation rate of contaminants can improve the performance of the composite liner.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2022)
Article
Engineering, Geological
Huaxiang Yan, Andrey P. Jivkov, Majid Sedighi
Summary: Understanding of desiccation-induced cracking in soil has improved through experimental studies, but predictive modeling has been limited. The authors present a non-local hydro-mechanical model based on peridynamics theory to predict crack initiation and growth. The model describes soil desiccation cracking as a hydro-mechanical problem, allowing for investigation of the mechanisms controlling crack formation and propagation.
Article
Engineering, Geological
Huaxiang Yan, Haijian Xie, Hao Ding, Dandi Yang, Cong Chen, Yunmin Chen, Yun Chen
Summary: A composite liner system consisting of a geomembrane layer, a compacted clay layer, and an attenuation layer is widely used in landfills. Consolidation of the soil liner can have detrimental effects on contaminant breakthrough, particularly under relatively high stress caused by waste placement. This study develops a one-dimensional model to investigate the transport behavior of contaminants in the composite liner system considering consolidation. The results show that the volume compressibility coefficient in the attenuation layer and the thickness of the attenuation layer play important roles in controlling the consolidation induced effects.
INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS
(2022)
Article
Engineering, Civil
Huaxiang Yan, Majid Sedighi, Hao Ding, Zhilin Sun, Haijian Xie
Summary: An analytical solution for the non-isothermal diffusion of organic compounds in the unsaturated GMB/CCL composite liner is proposed and tested against benchmarks for accuracy. The study shows that thermal gradient can affect contaminant diffusion through Soret effect and temperature dependent coefficient in GMB. It is indicated that transitioning from saturated to unsaturated state in the liner can significantly reduce contaminant concentration and flux.
JOURNAL OF HYDROLOGY
(2021)
Article
Environmental Sciences
Haijian Xie, Xinru Zuo, Yunmin Chen, Huaxiang Yan, Junjun Ni
Summary: The quantitative assessment of landfill gas emissions is crucial for evaluating the performance of landfill cover systems and gas collection systems. However, the use of static flux chamber technique may result in relative errors in measuring surface emissions of landfill gas. In this study, an integrated approach of in situ tests and numerical modeling was used to quantify the effects of chamber size, insertion depth, and pressure differential on the relative errors. The results showed that the proposed model based on the dusty-gas model (DGM) had a better capacity to predict gas transport compared to Blanc's method. Increasing the size and insertion depth of static chambers could reduce the relative error for CH4 and CO2 flux, while positive pressure differentials led to higher gas emission fluxes.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2022)
Article
Engineering, Geological
Haijian Xie, Jiawei Wu, Hywel R. Thomas, Peifu Cai, Huaxiang Yan, Yun Chen
Summary: This study investigates the effects of leachate head variations on contaminant transport in landfill sites. The results show that variations in leachate head can cause time-dependent changes in seepage velocity and alter the transport mechanisms of contaminants. Considering the effects of leachate head variations is critical in designing a stable and reliable landfill liner.
INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS
(2023)
Article
Engineering, Geological
Huaxiang Yan, Haijian Xie, Hamid Rajabi, Xiting Gu, Yun Chen
Summary: This study proposes an analytical solution for a one-dimensional and steady-state model to analyze the diffusion of VOCs within landfill capillary cover systems under unsaturated water flow and stable conditions. The research examines the impact of evaporation rate and clay thickness on coupled water flow and VOCs diffusion. The findings reveal the importance of considering unsaturated water flow in assessing VOC emissions in the cover system.
INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS
(2023)
Article
Environmental Sciences
Haijian Xie, Jiawei Wu, Mengzhen Yu, Huaxiang Yan, Shakil Masum, Peifu Cai, Yun Chen
Summary: Through experimental investigation, it was found that BPA can be adsorbed by organo-bentonites, and the adsorption capacity is 4.2 and 4 times higher than that of untreated loess, respectively. The modified loess can also reduce the permeability of BPA. The study suggests that organo-bentonites can effectively improve the impermeability of loess-based liners.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2023)
Article
Environmental Sciences
Hao Ding, Haijian Xie, Peifu Cai, Liang Wang, Huaxiang Yan, Aimin Jin, Yun Chen
Summary: This study develops alternative formulations for transient analytical modeling of organic contaminant transport in a composite of geosynthetic clay and attenuation layer system. The Laplace transform method is used to derive the solution. The proposed analytical frameworks are validated by benchmark tests and applied to evaluate various cases of organic contaminant transport.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2023)