Article
Green & Sustainable Science & Technology
Rahim Habibi, Shokrollah Zare, Amin Asgari, Mrityunjay Singh, Saeed Mahmoodpour
Summary: This study presents the coupled Thermal-Hydraulic-Mechanical-Chemical (THMC) processes in the storage and disposal of hydrocarbons, hydrogen, compressed air, and nuclear waste in salt formations. The aim is to identify key parameters associated with each process and evaluate available simulation codes/software. The outcome of this study will help design a comprehensive framework to enhance environmental and operational safety measures.
RENEWABLE & SUSTAINABLE ENERGY REVIEWS
(2023)
Article
Energy & Fuels
Jose A. Bosch, Yafei Qiao, Alessio Ferrari, Lyesse Laloui
Summary: The FEBEX test was a long-term project to assess the deep geological disposal of nuclear waste. It aimed to evaluate the reliability of numerical methods in predicting the physical processes in a geological repository. Despite previous studies demonstrating the performance of current models in capturing temperature and humidity evolution, uncertainties remained in predicting the stress-strain behavior of the bentonite seal. This paper used a recently developed THM elastoplastic constitutive model to analyze the bentonite barrier of the FEBEX test, obtaining good predictions and providing new insights on its heterogeneous state.
GEOMECHANICS FOR ENERGY AND THE ENVIRONMENT
(2023)
Article
Engineering, Geological
David Holton, David Roberts, Thomas Williams
Summary: This paper describes a methodology for evaluating the influence of thermal stress on fracture aperture around a Geological Disposal Facility (GDF), and presents calculations on an illustrative Discrete Fracture Network (DFN) to estimate the responses of the fractures to rock stress changes.
ENGINEERING GEOLOGY
(2023)
Article
Thermodynamics
Xudong Liu, Shuxun Sang, Xiaozhi Zhou, Ziliang Wang
Summary: In this paper, a fully coupled AHTMC model is constructed and applied to study CO2 enhanced coalbed methane. The simulation results show that CO2 injection can significantly decrease CH4 adsorption capacity, increase production rate, but also affect CO2 storage and drainage pH. The injection rate of CO2 has a significant influence on CO2-ECBM.
Article
Engineering, Geological
Tuan Nguyen-Sy, Minh-Ngoc Vu, Thoi-Trung Nguyen
Summary: A hybrid Laplace-Galerkin method is proposed for modeling thermo-hydro-mechanical coupled problems of fluid saturated porous media in unsteady state regime. This technique does not require any time stepping and achieves accurate results by transforming weak form equations into Laplace space and using Galerkin finite element method.
INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS
(2021)
Article
Chemistry, Multidisciplinary
Alireza Mokhtari Varnosfaderani, Ehsan Motevali Haghighi, Behrouz Gatmiri, Seonhong Na
Summary: The study investigates the impacts of climate change on unsaturated porous media through a coupled thermo-hydro-mechanical analysis. A new model is proposed to evaluate the applicability of the findings, and numerical examples demonstrate the effectiveness and feasibility of the model for practical application.
APPLIED SCIENCES-BASEL
(2021)
Article
Computer Science, Interdisciplinary Applications
Eleonora Sailer, David M. G. Taborda, Lidija Zdravkovic, David M. Potts, Wenjie Cui
Summary: This study investigates the impact of thermal-active structures exchanging heat with the ground, analyzing one-dimensional problems and establishing dimensionless parameters to evaluate THM interactions and their evolution over time. Results show that in THM modeling of thermo-active retaining walls, the structural response is influenced by various factors including thermal expansion of soils, volumetric deformations due to pore water generation, and mechanical boundary conditions. Therefore, performing accurate THM analyses and estimating hydraulic and thermal properties correctly are crucial for ensuring the safe design of thermo-active structures.
COMPUTERS AND GEOTECHNICS
(2021)
Article
Environmental Sciences
Michael O. Schwartz
Summary: The research on the Columbia River Basalt focuses on minimizing CO(2) emissions through underground waste disposal projects, providing a database for high-capacity CO(2) sequestration. Due to geomechanical constraints, the injection rate of CO(2) sequestration must be limited. The large underground space in the Columbia River Basalt provides a rare asset for waste disposal, occupying only a small fraction compared to a nuclear waste repository.
ENVIRONMENTAL TECHNOLOGY
(2022)
Article
Computer Science, Interdisciplinary Applications
Jintong Zhang, Junyu Chen, Zhihong Zhao, Sicong Chen, Guihong Liu, Xingguang Zhao, Ju Wang, Tao Lin, Bing Liu
Summary: Research has found that coupled thermo-hydro-mechanical (THM) processes have a significant impact on the transport behavior of nuclides in long-term operation of nuclear waste repositories, especially in the early stages of leaching. The thermal stress induced by heat release from nuclear waste leads to a reduction in fracture aperture around the repository, while inclined fractures delay the transport of nuclides.
COMPUTERS AND GEOTECHNICS
(2023)
Article
Computer Science, Interdisciplinary Applications
Tuan A. Pham, Gabriela M. Medero, Melis Sutman
Summary: This paper presents a thermohydro-mechanical coupled model of the elastic modulus characteristic curve (EMCC) based on the effective stress theories of unsaturated soils. The proposed model uses the soil-water characteristic curve (SWCC) and the modulus of elasticity under saturated conditions to predict the variation of modulus of elasticity with matric suction for unsaturated soils. The successful prediction performance of the proposed model is demonstrated by comparing measured and predicted outcomes for various published data sets related to different soil types.
COMPUTERS AND GEOTECHNICS
(2023)
Article
Computer Science, Interdisciplinary Applications
Yi Liu, Guoqing Cai, Annan Zhou, Bowen Han, Jian Li, Chengang Zhao
Summary: This work introduces a fully coupled constitutive model for the thermo-hydro-mechanical behavior of unsaturated soils, which considers key features of unsaturated soils and is validated against experimental data. The model is shown to exhibit basic properties and performance through a numerical example.
COMPUTERS AND GEOTECHNICS
(2021)
Article
Engineering, Geological
Guoqing Cai, Yi Liu, Zimeng Liu, Annan Zhou, Jian Li, Chenggang Zhao
Summary: The volume change behavior of unsaturated compacted loess under thermo-hydro-mechanical loads was investigated in this experimental research. A new temperature/suction-controlled triaxial apparatus with triple cells was developed. Various tests were conducted on an unsaturated compacted loess from Shaanxi, China, including temperature- and suction-controlled isotropic tests, heating-cooling tests, and drying-wetting tests. Experimental results showed different variation trends of compressibility indices with changes in suction, and both suction hardening and thermal softening were observed. The compacted loess exhibited irreversible volumetric contraction upon heating-cooling path, and the contraction was more significant at higher isotropic net stresses and higher suctions. The over-consolidation ratio prior to heating influenced the extent of irreversible contraction in loess samples. Water-holding capacity decreased upon heating, but it was independent of the stress level. The hydraulic hysteresis of samples remained unchanged with temperature changes. Slight shrinkage occurred during drying process, while collapse was observed during wetting process. Heating had limited effect on the drying shrinkage but induced more distinctive wetting collapse in loess samples.
Article
Energy & Fuels
Yilong Yuan, Tianfu Xu, Fabrizio Gherardi, Hongwu Lei
Summary: Within the context of deep geological disposal of high-level radioactive waste, thermo-hydro-mechanical (THM) coupled numerical modeling is crucial. This study incorporates a 3D mechanical module into the thermal-hydraulic coupled code TOUGH2, creating an integrated THM coupled simulator called TOUGH2Biot. The improved simulator is used to analyze the coupled THM behaviors of Callovo-Oxfordian claystone induced by thermal loading, considering anisotropy of material parameters and in-situ stresses. The modeling results replicate field observations and provide insights into the complex THM problem.
Article
Computer Science, Interdisciplinary Applications
Tsubasa Sasaki, Jonny Rutqvist
Summary: Geologic disposal is a promising solution for safe permanent isolation of high-level nuclear waste, and researchers have developed a method to estimate stress and permeability changes, successfully matching these values in simulations.
COMPUTERS AND GEOTECHNICS
(2021)
Article
Engineering, Environmental
Reza Ershadnia, Corey D. Wallace, Sassan Hajirezaie, Seyyed Abolfazl Hosseini, Thanh N. Nguyen, Daniel Murray Sturmer, Zhenxue Dai, Mohamad Reza Soltanian
Summary: This study investigates the effects of different factors on the effectiveness of geological carbon sequestration through a CO2 injection pilot project. The results show that neglecting thermal effects, geochemical reactions, capillary pressure heterogeneity, geomechanical processes, and permeability enhancement can all impact the sequestration efficiency. This has practical implications for designing effective field scale experiments and numerical simulations of geological carbon sequestration.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Oceanography
Mohammad Sarfaraz, Ali Pak
Article
Engineering, Geological
S. Reza Taheri, Ali Pak
ROCK MECHANICS AND ROCK ENGINEERING
(2020)
Article
Mining & Mineral Processing
S. Reza Taheri, Ali Pak, Saeed Shad, Behzad Mehrgini, Meisam Razifar
INTERNATIONAL JOURNAL OF MINING SCIENCE AND TECHNOLOGY
(2020)
Article
Engineering, Geological
Majid Fetrati, Ali Pak
JOURNAL OF ROCK MECHANICS AND GEOTECHNICAL ENGINEERING
(2020)
Article
Engineering, Geological
Seyyed-Kazem Razavi, Masoud Hajialilue-Bonab, Ali Pak
Summary: This paper discusses the determination of mechanical properties of plastic concrete for a new cutoff wall, with a detailed numerical simulation analyzing the influence of past and upcoming loading on the cutoff wall behavior. The study concludes the required mechanical properties for the plastic concrete after considering static and dynamic loading effects.
INTERNATIONAL JOURNAL OF GEOMECHANICS
(2021)
Article
Engineering, Geological
Habibollah Sadeghi, Ali Pak, Amin Pakzad, Peyman Ayoubi
Summary: Liquefaction is the phenomenon where saturated sandy soil loses its shear strength and turns into a liquefied state, causing detrimental consequences such as post-earthquake settlements and potential floods. Previous studies were limited in scope and did not consider realistic loadings and boundary conditions in field conditions. Accurate simulation of liquefaction-induced settlement requires fully coupled hydro-mechanical numerical analysis.
SOIL DYNAMICS AND EARTHQUAKE ENGINEERING
(2021)
Article
Energy & Fuels
Morteza Esfandiari, Ali Pak
Summary: This study evaluates the effects of in-situ stress on hydraulic fracture characteristics using the XFEM method. The accuracy of the analytical formulas of KGD and PKN models is examined by conducting numerical simulations. The results show that the analytical formulas differ from the numerical simulations due to simplifying assumptions and neglecting certain parameters. Correction factors are proposed to improve the results of KGD and PKN models. The findings of this study can contribute to more accurate design of hydraulic fracture processes in the oil industry for increased hydrocarbon reservoir production.
JOURNAL OF PETROLEUM EXPLORATION AND PRODUCTION TECHNOLOGY
(2023)
Article
Engineering, Geological
S. Morteza Mousavi, Ernest Yanful, M. Hesham El Naggar, Behrouz Gatmiri, Ali Pak
Summary: Groundwater overwithdrawal leads to accelerated global development, increasing demands on unsaturated zones. Estimating evaporation from unsaturated soil is crucial for various engineering applications, and it is influenced by factors such as soil properties and environmental data. In this study, the program EVAP1 was developed using a two-dimensional model with atmospheric coupling and a modified Penman equation to numerically estimate potential and actual evaporation from unsaturated soil.
INTERNATIONAL JOURNAL OF GEOMECHANICS
(2022)
Article
Engineering, Geological
Jafar Maleki, Ali Pak
Summary: Deep excavations are commonly seen geotechnical structures in urban areas, but they may cause harmful effects on adjacent structures. Therefore, accurate soil parameters, rigorous design, and monitored construction are crucial for the success of such projects. Soil-nail walls, known for their simplicity and cost-effectiveness, are commonly used. To simplify the design process and reduce the need for numerical modeling, the Multivariate Adaptive Regression Splines (MARS) method has been employed.
GEOTECHNICAL AND GEOLOGICAL ENGINEERING
(2023)
Article
Engineering, Marine
Mohammad Mohammadnia, Ali Pak
Summary: Recently, designers have focused on low-crested/submerged breakwaters due to their advantages, but there is no comprehensive formula for designing the cube armour layer for these types of breakwaters. This article presents a comprehensive formula for design based on experiments, including important parameters such as crest width, packing density, placement pattern, slope, freeboard, and wave characteristics. The formula's hydraulic stability number shows favorable accuracy compared to laboratory values, indicating its applicability for safe design of the armour layer.
Article
Engineering, Geological
Sedigheh Masoudi, Hadi Shahir, Ali Pak
Summary: This study used the CEL method to simulate the construction of rubble mound breakwaters on soft soil and predict the resulting settlements. The results indicated that the CEL method can accurately predict the deformations and settlements of rubble mound breakwaters on soft soils. Additionally, a parametric study was conducted to investigate the effects of various parameters on the amount of settlement in soft soil conditions.
INDIAN GEOTECHNICAL JOURNAL
(2021)
Article
Engineering, Geological
Ali Pak, Jafar Maleki, Nima Aghakhani, Mojtaba Yousefi
Summary: This study analyzed the behavior of soil-nailed walls through numerical modeling and conducted numerous parametric studies to investigate the stability of deep excavations with different geometries. A simplified equation was developed to predict the deflections of deep excavations, aiming to enhance safety measures during construction and stabilization processes.
GEOMECHANICS AND GEOENGINEERING-AN INTERNATIONAL JOURNAL
(2021)
Article
Engineering, Geological
Ali Ghassemi, Javad Abbaszadeh, Ali Pak
Article
Engineering, Multidisciplinary
A. Pak, M. A. Iranmanesh
Proceedings Paper
Green & Sustainable Science & Technology
Mehrzad Rahimi, Parisa Shahbazan, Amin Gheibi, Ali Khosravi, Ali Pak, Mehdi Yarmahmoodi
GEO-SYSTEMS, SUSTAINABILITY, GEOENVIRONMENTAL ENGINEERING, AND UNSATURATED SOIL MECHANICS (GEO-CONGRESS 2020)
(2020)
Article
Computer Science, Interdisciplinary Applications
Yinghao Deng, Yang Xia, Di Wang, Yan Jin
Summary: This study investigates the mechanism of hydraulic fracture propagation in laminated shale, develops a numerical solver, and validates the effectiveness of the method through simulation experiments. The study also examines the influence of the interaction between hydraulic fractures and weak interfaces on the mechanical properties of shale.
COMPUTERS AND GEOTECHNICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Zhichao Zhang, Mingfei Feng, Guangshuo Zhou, Zhenglong Xu
Summary: A thermodynamic constitutive model for structured and destructured clays is proposed in this paper. The model includes state-dependent relations of hyperelasticity and plasticity without the concept of yielding surface. The proposed model captures the couplings between elasticity and plasticity and the effects of bonding structure.
COMPUTERS AND GEOTECHNICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Deze Yang, Xihua Chu
Summary: Creep and stress relaxation behaviors in granular materials are influenced by the time-dependent changes in their microstructure, with particle shape playing a significant role. However, the effects of particle shape on these behaviors are still not well understood. In this study, 3D DEM models incorporating the rate process theory and superellipsoids are used to simulate creep and stress relaxation in granular samples with different aspect ratios and blockiness. The results show that both aspect ratio and blockiness have a significant influence on creep and stress relaxation, with aspect ratio affecting creep through contact force ratio and blockiness affecting stress relaxation through variation in normal contact force anisotropy. These findings provide insights into the effects of particle shape on creep and stress relaxation in granular assemblies.
COMPUTERS AND GEOTECHNICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Shahab Amanat, Kourosh Gholami, Reza Rafiee-Dehkharghani, Dipanshu Bansal
Summary: This paper investigates the optimal design of wave barriers using the modified non-dominated sorting genetic algorithm-II (NSGA-II) and the Bloch-Floquet theory. The aim is to find the optimal design of plane wave barriers with a wide bandgap at a low-frequency range and low construction cost. The study develops a modified NSGA-II algorithm to determine the optimal arrangement of concrete in wave barrier unit cells. The performance of the optimal barriers is examined through finite element simulation and their efficacy in attenuating plane S-waves is verified.
COMPUTERS AND GEOTECHNICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Yanlin Su, Guoqing Cai, Fengjie Yin, Yepeng Shan, Annan Zhou
Summary: This paper presents a novel elastic-viscoplastic constitutive model that takes into account particle breakage to reproduce the time-dependent behavior of coarse-grained soil. The model integrates the Unified Hardening (UH) model, the elastic-viscoplastic (EVP) model, and the overstress theory. The relationship between particle breakage and loading rate is established, and state variables associated with the critical state of coarse-grained soil are derived to consider both time and particle breakage. A three-dimensional elastic-viscoplastic constitutive model is constructed by combining a one-dimensional viscoplastic hardening parameter with a secondary consolidation coefficient considering particle breakage. The proposed model requires 19 parameters and effectively describes the influence of time-dependency and particle breakage on the shear, dilatancy, and compression behaviors of coarse-grained soil with different confining pressures or initial void ratios. Experimental data comparisons validate the model's ability to replicate the time-dependent behavior of coarse-grained soil.
COMPUTERS AND GEOTECHNICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Shichao Zhang, Yaqiong Wang, Qidong Gao, Xiaobo Ma, Haixiao Zhou, Zhifeng Wang
Summary: Accurately evaluating and predicting ground settlement during tunnel excavation is essential for ensuring tunnel stability. This study conducted a probabilistic analysis of ground settlement under uncertain soil properties. The results demonstrate that spatially variable soils significantly influence the ground settlement in the vertical direction.
COMPUTERS AND GEOTECHNICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Xu Zhang, Bin Luo, Youjun Xu, Zhiwen Yang
Summary: This paper presents an analytical solution for horizontal displacements induced by small radius curve shield tunneling. The formula is derived based on the image method and Mindlin solution, considering additional thrust, frictional resistance, ground loss, and grouting pressure. The solution is validated with on-site data, demonstrating its reliability and providing a new approach for predicting and controlling stratum horizontal displacements in curve shield tunneling. The study finds that ground loss has the most significant influence on displacements, and soil closer to the tunnel exhibits larger horizontal displacements.
COMPUTERS AND GEOTECHNICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Jian-Hong Wan, Ali Zaoui
Summary: Ground vibrations during earthquakes can cause soil strength loss and structural damage. Rubber-soil mixtures (RSM) have shown promise in reducing residual ground deformation. This study used molecular dynamics simulations to investigate the friction behavior of the rubber-clay interface in RSM systems. The results revealed a direct correlation between normal stress and friction force, with denser soil systems exhibiting higher friction forces.
COMPUTERS AND GEOTECHNICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Hongying Wang, Qiang Zhang, Peinan Wu, Yanjing Li, Lijun Han, Guilei Han
Summary: In addition to the Mohr-Coulomb and Hoek-Brown criteria, other nonlinear functions are used to describe the plastic response of rock mass. This paper derived the equivalent cohesive strength, frictional angle, and dilatancy angle for nonlinear yield and plastic flow rock masses. The solution for a circular tunnel in any nonlinear yield and plastic flow rock masses was derived and verified using a numerical procedure. The analysis of strain-softening rock masses under two assumed nonlinear yield criteria was also studied.
COMPUTERS AND GEOTECHNICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Zhijun Wu, You Wu, Lei Weng, Mengyi Li, Zhiyang Wang, Zhaofei Chu
Summary: This study proposed a machine learning approach to predict the uniaxial compression strength (UCS) and elastic modulus (E) of rocks. By measuring meso-mechanical parameters and developing grain-based models, a database with 225 groups of data was established for prediction models. The optimized kernel ridge regression (KRR) and gaussian process regression (GPR) models achieved excellent performance in predicting UCS and E.
COMPUTERS AND GEOTECHNICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Mingjun Zhou, Zhenming Shi, Chong Peng, Ming Peng, Kahlil Fredrick E. Cui, Bo Li, Limin Zhang, Gordon G. D. Zhou
Summary: In this paper, the erosion and deposition processes during overtopping dam breaching are simulated using a novel method (ED-SPH). The proposed model is able to capture the complex behaviors of dam soil erosion, entrainment, and depositions. Soil deposition hinders particle movement and reduces water velocity at the water-soil interface.
COMPUTERS AND GEOTECHNICS
(2024)
Article
Computer Science, Interdisciplinary Applications
C. Chavez-Negrete, F. J. Dominguez-Mota, R. Roman-Gutierrez
Summary: To accurately simulate groundwater flow in porous layered media, it is important to consider all environmental factors and use a generalized finite differences scheme as a meshless method for spatial discretization. This approach ensures robustness and accuracy of the numerical solution.
COMPUTERS AND GEOTECHNICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Shuairun Zhu, Lulu Zhang, Lizhou Wu, Lin Tan, Haolong Chen
Summary: This paper investigates the effectiveness of the cascadic multigrid method applied to the improved Picard iteration method for solving nonlinear problems in deforming variably saturated porous media. Two improved Picard iteration methods are proposed, and their effectiveness is verified through numerical examples. The results show that the improved methods have faster convergence and higher computational efficiency compared to the classical method.
COMPUTERS AND GEOTECHNICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Yuan Cao, Yan-Guo Zhou, Kyohei Ueda, Yun-Min Chen
Summary: Investigated shear stress responses of enclosed soil in deep soil mixing (DSM) grid-improved ground, and revealed the characteristics of the waist effect and mathematical model for shear stress reduction ratio.
COMPUTERS AND GEOTECHNICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Jinfan Chen, Zhihong Zhao, Jintong Zhang
Summary: This study develops data-driven criteria to estimate the peak shear strength (PSS) of rock fractures, considering the effects of surface roughness features. A high-quality dataset is created using particle-based discrete element method and diamond-square algorithm. Tree-based models and convolutional neural network are trained to predict the PSS of rock fractures, and their reliability is verified using experimental data.
COMPUTERS AND GEOTECHNICS
(2024)
