Geomechanics for Energy and the Environment最新文献

{"title":"Study on the interaction between pile and soil under lateral load in coral sand","authors":"Bingxiang Yuan ,&nbsp;Qingyu Huang ,&nbsp;Weiyuan Xu ,&nbsp;Zejun Han ,&nbsp;Qingzi Luo ,&nbsp;Guorong Chen ,&nbsp;Junhong Yuan ,&nbsp;Qiyong Zhang ,&nbsp;Sabri Mohanad Muayad Sabri","doi":"10.1016/j.gete.2025.100674","DOIUrl":"10.1016/j.gete.2025.100674","url":null,"abstract":"<div><div>In complex marine environments, research on the response of single piles to lateral loads under different coral sand grain sizes and different embedment depths of the pile body is relatively limited. This study employed indoor scaled-model tests combined with PIV technology, focusing on two variables: coral sand particle sizes and embedment depths of rigid piles. The effects on the bending moment of single piles, the resistance of coral sand, and the displacement of the pile shaft and pile top in coral sand layers were analyzed. The study also revealed the distribution and development patterns of horizontal strain in coral sand particles around the pile top when subjected to lateral loads. The results showed that, as particle size decreased, the maximum bending moment of the pile and the resistance of coral sand increased, the rotation point of pile displacement rose, and pile top displacement increased. In addition, smaller particles had weaker interlocking, resulting in less effective force chain transmission and lower load diffusion. When the embedment depth of the rigid pile decreased, lateral loads could not be transferred to deeper soil layers, leading to more noticeable displacements at the pile shaft and pile top.</div></div>","PeriodicalId":56008,"journal":{"name":"Geomechanics for Energy and the Environment","volume":"42 ","pages":"Article 100674"},"PeriodicalIF":3.3,"publicationDate":"2025-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143826154","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study on the characteristics of coal pore structure changes during hot flue gas displacement and their impact on the gas displacement effect","authors":"Jiahao He ,&nbsp;Baiquan Lin ,&nbsp;Tong Liu ,&nbsp;Zhenyong Zhang ,&nbsp;Shuai Le ,&nbsp;Yajie Hu","doi":"10.1016/j.gete.2025.100673","DOIUrl":"10.1016/j.gete.2025.100673","url":null,"abstract":"<div><div>Gas displacement by hot flue gas injection into the coal body is a hot spot in the research on high-gas and low-permeability coal seams. Injecting hot flue gas generated by gas power plants into coal seams will introduce water and CO₂, and the introduced CO₂ will dissolve and ionize to form an acidic environment, leading to the dissolution of minerals in coal. Therefore, it is particularly important to study the impact of coal pore structure changes on gas displacement before and after mineral dissolution. In this study, the impact of mineral dissolution in coal was explored by combining Computed Tomography (CT) and COMSOL Multiphysics numerical simulation, and the parameters of the numerical model were determined based on gas adsorption-desorption experimental results. The following conclusions were drawn at the millimeter scale: (1) Compared with the Langmuir equation, the BET equation is more competent to act as an isothermal adsorption and desorption model of coal in high-gas and low-permeability coal seams. (2) After 10.11 % of minerals dissolve, the flow velocity and outlet flow rate in the fractures formed at the original positions of minerals both increase significantly, and the model permeability grows from 7.0711 × 10⁻¹² m² to 2.2331 × 10⁻¹¹ m². (3) The time consumed for the residual gas pressure to drop from its initial value to 0.1 MPa was calculated. (4) After mineral dissolution, the coal pore structure alters, resulting in changes in the distribution of gas pressure during displacement, and the gas pressure varies obviously spatially.</div></div>","PeriodicalId":56008,"journal":{"name":"Geomechanics for Energy and the Environment","volume":"42 ","pages":"Article 100673"},"PeriodicalIF":3.3,"publicationDate":"2025-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143800013","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development and validation of TOUGH-3DEC: A three-dimensional discontinuum-based numerical simulator for coupled thermo-hydro-mechanical analysis","authors":"Saeha Kwon,&nbsp;Kwang-Il Kim,&nbsp;Changsoo Lee,&nbsp;Jaewon Lee,&nbsp;Jin-Seop Kim","doi":"10.1016/j.gete.2025.100670","DOIUrl":"10.1016/j.gete.2025.100670","url":null,"abstract":"<div><div>The discontinuum-based numerical methods can simulate the coupled thermo-hydro-mechanical (THM) processes in porous media with multiple discontinuities, so it is appropriate to model the mechanical behavior of a fractured host rock under the coupled processes such as a geological repository for high-level radioactive waste. TOUGH-3DEC, a three-dimensional discontinuum-based simulator for the coupled THM analysis, was developed by linking the integral finite difference method TOUGH2 and the distinct element method 3DEC to describe the coupled THM processes in porous media and discontinuous media. TOUGH2 handles the coupled TH analysis through the internal simulation module, while 3DEC performs mechanical analysis based on the constitutive models of porous media and discontinuity, coupling the thermal and hydraulic responses from TOUGH2. The thermal and hydraulic couplings are key processes and should be carefully verified by sufficient cases, so this study performed TM and HM verifications by modelling analytic solutions including the uniaxial consolidation, fracture static opening, and the heating of a hollow cylinder. As comparative validations, two models describing laboratory-scale experiments regarding the HM and TM processes of fractured rock were simulated and compared to the experimental results. The developed TOUGH-3DEC simulator showed sufficient accuracy in reflecting the coupled THM processes of the small-scale discontinuous rock, but still needs to be verified by more complicated and large-scale coupled process problems to be applicable to the demonstration of the field-scale model requiring the coupled THM processes of various geological media, such as a multi-barrier system of a geological repository.</div></div>","PeriodicalId":56008,"journal":{"name":"Geomechanics for Energy and the Environment","volume":"42 ","pages":"Article 100670"},"PeriodicalIF":3.3,"publicationDate":"2025-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143815438","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental study on the swelling pressure of compacted bentonite under high temperatures above 100 °C","authors":"Jang-Un Kim ,&nbsp;Hyunwook Choo ,&nbsp;Boyoung Yoon ,&nbsp;Susan E. Burns","doi":"10.1016/j.gete.2025.100671","DOIUrl":"10.1016/j.gete.2025.100671","url":null,"abstract":"<div><div>Disposal and storage of high-level nuclear waste in deep geological repositories requires understanding the behavior of compacted clay at high maximum design temperatures (&gt; 100 °C); however, the effect of temperature variations on the swelling pressure of compacted bentonite has generally been examined within a restricted temperature range of 20–90 °C. Consequently, this experimental investigation uses specially designed temperature-controlled apparatus to determine the swelling pressure of compacted Na-bentonite across a temperature span of 10–160 °C. The poro-thermal and chemo-thermal effects on the swelling pressure of bentonite were studied using three dry densities (1.20, 1.35 and 1.50 Mg/m³) and three electrolyte concentrations (de-ionized water, NaCl 0.1 M and 0.5 M solutions). A linear relationship was observed between the normalized swelling pressure (the ratio of swelling pressure at a specific temperature to the swelling pressure at 25 °C) and temperature under the tested temperature ranges, suggesting that the swelling pressure measured at relatively low temperature ranges (below 100 °C) could be used to estimate the high temperature (above 100 °C) swelling pressure based on extrapolation. The swelling pressure increased with temperature, and higher dry densities and lower electrolyte concentrations amplified this effect. The complex interplay of dry density, pore fluid concentration, and temperature on the swelling behavior of compacted bentonite was explained based on the competition between the interlayer and interparticle swelling pressures.</div></div>","PeriodicalId":56008,"journal":{"name":"Geomechanics for Energy and the Environment","volume":"42 ","pages":"Article 100671"},"PeriodicalIF":3.3,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143807367","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical simulation of coupled THM behaviour of full-scale EBS in backfilled experimental gallery in the Horonobe URL","authors":"Yutaka Sugita ,&nbsp;Hirokazu Ohno ,&nbsp;Steffen Beese ,&nbsp;Pengzhi Pan ,&nbsp;Minseop Kim ,&nbsp;Changsoo Lee ,&nbsp;Carlos Jove-Colon ,&nbsp;Carlos M. Lopez ,&nbsp;Suu-yan Liang","doi":"10.1016/j.gete.2025.100668","DOIUrl":"10.1016/j.gete.2025.100668","url":null,"abstract":"<div><div>Bentonite-based engineered barrier system (EBS) is a key component of many repository designs for the geological disposal of high-level radioactive waste. Given the complexity and interaction of the phenomena affecting the barrier system, coupled thermo-hydro-mechanical (THM) numerical analyses are a potentially useful tool for a better understanding of their behaviour. In this context, a Task (the Horonobe EBS experiment) was undertaken to study, using numerical analyses, the thermo-hydro-mechanical (and thermo-hydro) interactions in bentonite based engineered barriers within the international cooperative project DECOVALEX 2023. One full-scale in-situ experiment and four laboratory experiments, largely complementary, were selected for modelling. The Horonobe EBS experiment is a temperature-controlled non-isothermal experiment combined with artificial groundwater injection. The Horonobe EBS experiment consists of the heating and cooling phases. Six research teams performed the THM or TH (depended on research team approach) numerical analyses using a variety of computer codes, formulations and constitutive laws. For each experiment, the basic features of the analyses are described and the comparison between calculations and laboratory experiments and field observations are presented and discussed.</div></div>","PeriodicalId":56008,"journal":{"name":"Geomechanics for Energy and the Environment","volume":"42 ","pages":"Article 100668"},"PeriodicalIF":3.3,"publicationDate":"2025-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143776650","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical investigation of the gas-induced fracturing behavior of the Callovo-Oxfordian claystone","authors":"Carlos Plúa ,&nbsp;Rémi de La Vaissière ,&nbsp;Gilles Armand ,&nbsp;Sebastià Olivella ,&nbsp;Alfonso Rodriguez-Dono ,&nbsp;Zhan Yu ,&nbsp;Jian-fu Shao ,&nbsp;Eike Radeisen ,&nbsp;Hua Shao","doi":"10.1016/j.gete.2025.100669","DOIUrl":"10.1016/j.gete.2025.100669","url":null,"abstract":"<div><div>This paper presents a synthesis of the numerical approaches adopted by three research teams to reproduce gas fracturing initiation in the Callovo-Oxfordian claystone. This collaborative work has been carried out within the framework of the DECOVALEX-2023 project. First, the research teams investigated the impact of gas migration and fluid pressurization within the Callovo-Oxfordian claystone and the fracturing threshold pressure through a series of benchmark exercises under plane strain conditions with increasing complexity. The three numerical approaches accounted for couplings between the mechanical part and hydraulic parameters, such as permeability, through different variables such as damage, fracture aperture, or equivalent plastic strain. Then, the research teams utilized their models to reproduce two injection tests at the field-scale. A challenge faced by the research teams was dealing with a single study point per injection test, complicating the study of responses near the injection interval. This part included interpretative analyses with simplified approaches for a better understanding of gas pressure build-up. Overall, the numerical simulations yielded acceptable results in reproducing the in-tests after a calibration process and provided insights into the hydromechanical response of the Callovo-Oxfordian claystone under two-phase flow conditions. Nonetheless, the benchmark exercises showed that the numerical results using different mechanical constitutive models yielded different outcomes when reaching critical values leading to fracturing, which strongly depend on how the mechanical part influences the hydraulic response through the changes in hydraulic properties.</div></div>","PeriodicalId":56008,"journal":{"name":"Geomechanics for Energy and the Environment","volume":"42 ","pages":"Article 100669"},"PeriodicalIF":3.3,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143786026","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of chemical pollution from different pH solutions on evaporation and crack growth of granite residual soil","authors":"Yang Chen ,&nbsp;Liansheng Tang ,&nbsp;Weiya Ding ,&nbsp;Zihua Cheng","doi":"10.1016/j.gete.2025.100667","DOIUrl":"10.1016/j.gete.2025.100667","url":null,"abstract":"<div><div>In recent years, soil chemical pollution has emerged as a significant global environmental concern. Soil cracking induced by chemical pollution can alter the movement of water in the soil, consequently influencing the entire geological environment. Nevertheless, the consequences of diverse acid-alkali chemical pollutants on soil evaporation and cracking remain incompletely understood. In this investigation, the impact of varied pH chemical solutions on the evaporation and crack formation in granite residual soil (GRS) was examined. Mud samples were submerged in solutions of differing pH levels for 28 days while maintaining a constant temperature of 50°C. The findings demonstrate that as the pH of the solution increases, chemical pollution alters the inter-particle forces within soil, leading to an accelerated evaporation rate of GRS. At pH values of 3, 5, 7, 9, 11, and 13, the constant rate stage of soil water evaporation represented 78.9 %, 78.0 %, 76.1 %, 73.9 %, 69.6 %, and 69.0 % of the total evaporation time, respectively. Acid-alkali pollution significantly accelerates the development of cracks in GRS. For instance, at pH values of 3, 5, 9, 11, and 13, the final crack rate in soil samples increased by 56.56 %, 38.44 %, 19.06 %, 112.81 %, and 305.31 %, respectively, when compared to pH 7. The final fractal dimension of cracks increased by 2.29 %, 0.84 %, 0.63 %, 7.22 %, and 9.52 %, correspondingly. Varied pH levels in chemical solutions influence evaporation characteristics and crack development by altering the contact angle, the electric double layer (EDL), mineral composition, and the soil's microstructure. The research has uncovered an inverse relationship between the thickness of the EDL and contact angle or time of initial crack formation. Building upon this finding, a novel method is introduced to assess changes in EDL thickness. The findings of this study have practical implications for a range of applications related to hydrology and soil stability in the presence of acid-alkali pollution.</div></div>","PeriodicalId":56008,"journal":{"name":"Geomechanics for Energy and the Environment","volume":"42 ","pages":"Article 100667"},"PeriodicalIF":3.3,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143734573","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Energy quay walls: Performance analysis and optimisation","authors":"Marco Gerola ,&nbsp;Francesco Cecinato ,&nbsp;Vincent Leclercq ,&nbsp;Philip J. Vardon","doi":"10.1016/j.gete.2025.100664","DOIUrl":"10.1016/j.gete.2025.100664","url":null,"abstract":"<div><div>Energy Quay Walls (EQWs) are innovative energy geostructures with the unique capability to exchange heat with both soil and open water. Although previous laboratory testing demonstrated a promising energy efficiency for this type of system, its novelty necessitated thorough research to advance comprehension of its thermal behaviour and optimise energy efficiency. This paper conducts an in-depth examination of EQWs, employing numerical models validated against real data from a full scale test in Delft, The Netherlands.</div><div>Two Finite Element numerical models were developed to (i) reconstruct the undisturbed (i.e. pre-geothermal activation) temperature profile within the soil and (ii) conduct a comprehensive (3D) analysis of heat exchange processes in an EQW application (i.e. during geothermal activation), calibrating relevant parameters with field test data, providing valuable insights into its energy efficiency. Following validation, the geothermal activation model was employed to assess the impact of the flow regime within the heat exchanger pipes and the velocity of the open water on the energy efficiency of the EQW system. Additionally, the contributions of soil, water, and air to the energy gain are investigated. The results indicate that the primary source of energy gain is from open water, and the dominance of this contribution is further increased by the presence of turbulent flow within the heat exchanger pipes. However, the soil can play a key role in short term energy delivery. Furthermore, this study emphasises the importance of the open water movement, revealing a 48<span><math><mtext>%</mtext></math></span> reduction in energy extraction for fully stationary water scenarios.</div></div>","PeriodicalId":56008,"journal":{"name":"Geomechanics for Energy and the Environment","volume":"42 ","pages":"Article 100664"},"PeriodicalIF":3.3,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143739880","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of multifractal characteristics of pore structure in coal adsorbed by low pressure gas on thermal conductivity and thermal diffusion","authors":"Xiuming Jiang ,&nbsp;Caifang Wu ,&nbsp;Xiaojie Fang ,&nbsp;Yi Cheng","doi":"10.1016/j.gete.2025.100666","DOIUrl":"10.1016/j.gete.2025.100666","url":null,"abstract":"<div><div>Thermal conductivity and thermal diffusivity are critical physical properties influencing safe mining operations, geothermal field studies, and underground coal gasification technologies. This study investigates the pore structure and multifractal characteristics of coal with varying metamorphic degrees in southwest China using low-pressure N₂ and CO₂ adsorption techniques. The thermal conductivity and diffusivity of coal samples were measured using the transient plane source method. Furthermore, we analyzed the relationship between multifractal parameters and the thermal properties of coal. Our results indicate a weak correlation between industrial parameters and the thermal properties of coal. We found that the pore volume and specific surface area of intermediate pores in coal are positively correlated with thermal conductivity and negatively correlated with thermal diffusivity. Both thermal conductivity and diffusivity increase with the pore volume and specific surface area. Multifractal self-similarity analysis reveals that coal samples exhibit strong multifractal characteristics, with micropores displaying stronger multifractal features than intermediate pores. The distribution of pores in coal primarily influences thermal conductivity and diffusivity, whereas the structure and complexity of the pores themselves have a negligible effect compared to pore uniformity.</div></div>","PeriodicalId":56008,"journal":{"name":"Geomechanics for Energy and the Environment","volume":"42 ","pages":"Article 100666"},"PeriodicalIF":3.3,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143683855","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Three-dimensional elastoplastic modelling for deformation property of sandstone with dilatancy","authors":"Jiacun Liu ,&nbsp;Xing Li ,&nbsp;Ying Xu ,&nbsp;Kaiwen Xia","doi":"10.1016/j.gete.2025.100665","DOIUrl":"10.1016/j.gete.2025.100665","url":null,"abstract":"<div><div>Due to the development of plastic strains, the strain path within the meridian plane deviates from the reference line corresponding to elastic state. Similarly, under true triaxial stress conditions, the strain path within the deviatoric plane deviates from the reference line corresponding to the constant Lode angle. This deviation is attributed to the plastic shear strain associated with the Lode angle. To account for these phenomena, a novel three-dimensional elastoplastic constitutive model incorporating Lode angle is proposed to characterize the deformation behavior of sandstone. The yield and potential functions within this model incorporate parameters that vary with the plastic internal variable, enabling the evolution of the yield and plastic potential surfaces in both the meridian and deviatoric planes. The comparison between experimental data and the analytic solution derived from the constitutive model validates its reliability and accuracy. To examine the differences between yield surface and plastic potential surface, a comparison between the associated and non-associated flow rules is conducted. The results indicate that the associated flow rule tends to overestimate the dilatancy of sandstone. Furthermore, the role of Lode angle dependence in the potential function is explored, highlighting its importance in accurately describing the rock's deformation.</div></div>","PeriodicalId":56008,"journal":{"name":"Geomechanics for Energy and the Environment","volume":"42 ","pages":"Article 100665"},"PeriodicalIF":3.3,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143698121","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}