Geomechanics for Energy and the Environment最新文献

{"title":"Thermomechanical analysis method for energy piles with skin friction softening and hardening behavior","authors":"Huaibo Song ,&nbsp;Huafu Pei ,&nbsp;Hao Wang","doi":"10.1016/j.gete.2025.100744","DOIUrl":"10.1016/j.gete.2025.100744","url":null,"abstract":"<div><div>Various approaches have been proposed to analyze the thermomechanical behavior of individual energy piles. Although these approaches can account for pile-soil interactions, there is a lack of approaches for continuously describing the full nonlinear range of the load-transfer curve for individual energy piles under thermomechanical loading, including both skin friction softening and the hardening behavior. Therefore, this study developed an analysis method for individual energy piles by considering skin friction softening and hardening behaviors. The developed approach was verified by comparing the simulation results with those of three well-documented field tests, alongside laboratory and centrifuge model tests. The simulation results show a maximum percentage error between the simulation results and the field measurement results is 8.8 %, which is much smaller than that of other methods, indicating a relatively high degree of consistency between the simulation and the actual situation. Besides，the results suggest that the proposed method can capture the full nonlinear range of the load-transfer curve and essential aspects of the pile in terms of the stress and displacement induced by the thermomechanical operation. Finally, a parametric analysis was conducted to study the effects of the model parameters on the energy pile thermomechanical performance. Results show that increasing the dimensionless parameter changes the pile axial thermal stress and displacement oppositely; increasing the residual ratio boosts axial thermal stress, reduces displacements and stress, and moves the neutral point (NP) towards the pile head.</div></div>","PeriodicalId":56008,"journal":{"name":"Geomechanics for Energy and the Environment","volume":"44 ","pages":"Article 100744"},"PeriodicalIF":3.7,"publicationDate":"2025-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145106908","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 study on enhancing coalbed methane recovery using stress relief by multiple cavities","authors":"Yi Chen,&nbsp;Lei Zhou,&nbsp;Liulin Fang,&nbsp;Yu Peng,&nbsp;Xiaocheng Li","doi":"10.1016/j.gete.2025.100742","DOIUrl":"10.1016/j.gete.2025.100742","url":null,"abstract":"<div><div>Conventional horizontal well direct fracturing technology is inadequate for deep coalbed methane (DCBM) surface extraction. The extraction of DCBM presents a technical obstacle that impedes the advancement of China's CBM industry. This study explores the potential of a novel approach involving horizontal wells with multi-cavities to enhance DCBM extraction. A three-dimensional numerical tool, based on the elastic-plastic damage model and material point method (MPM), was developed to examine permeability enhancement and CBM desorption induced by cavities. Systematic engineering simulations were conducted to validate the effectiveness of DCBM extraction. The findings are as follows: 1) The three-dimensional numerical tool accurately simulates large deformation, large displacement, and inner boundary self-contact issues during cavity-induced collapse in deep coal. 2) A single cavity contributes an effective stress-relief volume 23.95 times greater than the cavity volume; permeability increases by 5–800 times in the plastic zones and by 1–5 times in the elastic zones over the initial permeability, and a total CBM desorption of 197.22 m³ is achieved. 3) The DCBM production volume enhanced by horizontal wells with multi-cavities is 24.98 times greater than hydraulic fracturing, with an average production exceeding 10,000 m³ /d and remaining above 6000 m³ /d after one year of extraction. 4) Optimal performance of horizontal wells with multi-cavities can be achieved by reducing the cavity angle and spacing while increasing the cavity width and length. Based on these results, implementing compound fracturing in horizontal wells with multi-cavities is recommended. This study provides a numerical tool and new insights for enhancing DCBM extraction.</div></div>","PeriodicalId":56008,"journal":{"name":"Geomechanics for Energy and the Environment","volume":"44 ","pages":"Article 100742"},"PeriodicalIF":3.7,"publicationDate":"2025-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145106905","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 evaluation of effective thermal conductivity in micro-carbon fiber reinforced clay soils with varying fiber distributions","authors":"Yuan Feng ,&nbsp;Jongwan Eun ,&nbsp;Seunghee Kim ,&nbsp;Yong-Rak Kim","doi":"10.1016/j.gete.2025.100743","DOIUrl":"10.1016/j.gete.2025.100743","url":null,"abstract":"<div><div>The effective thermal conductivity of Micro-Carbon Fiber Reinforced Soil (MCFRS) is critical in geothermal, energy, and environmental engineering. Due to the influence of the filament's shape of carbon fibers, it is important to understand the effect of fiber distribution in interpreting the thermal conductivity of fiber-reinforced soil. In this study, we evaluated the thermal conductivity of MCFRS using analytical solutions and finite element simulation methods in three-dimensional space, and discussed the effects of carbon fiber distribution and fiber type on thermal conductivity. The results showed that adding carbon fiber can effectively improve the thermal conductivity of soil, and the thermal conductivity of MCFRS was closely related to the distribution of fibers. By adding 1.0 % carbon fiber with a thermal conductivity of 1000 W/(m·K), the thermal conductivity of the composite material can be increased up to 292 %. Furthermore, the thermal conductivity of MCFRS is closely related to the distribution of fibers. In the case of parallel distribution, the thermal conductivity was 1.87 and 1.47 times that of purely random distribution and random distribution in the XZ/XY-plane, respectively, if the heat transfer is in the X-axis direction. This study provides evidence for the potential improvement of the thermal conductivity of MCFRS.</div></div>","PeriodicalId":56008,"journal":{"name":"Geomechanics for Energy and the Environment","volume":"44 ","pages":"Article 100743"},"PeriodicalIF":3.7,"publicationDate":"2025-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145106907","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":"Investigations into crack evolution during controlled continual laser-based rock processing","authors":"Antash K. Sinha ,&nbsp;Shrikrishna N. Joshi","doi":"10.1016/j.gete.2025.100741","DOIUrl":"10.1016/j.gete.2025.100741","url":null,"abstract":"<div><div>Laser-based rock processing presents a transformative approach for mining, drilling, tunnelling, and geothermal applications by addressing key limitations of conventional mechanical methods, including excessive tool wear and operational inefficiencies. Despite its promise, challenges such as anisotropic rock behaviour, power transmission, formation damage, and instability in subsurface conditions require further investigation. This study examines the effectiveness of continual laser-based rock processing in inducing controlled damage and crack propagation in limestone rock. Distinct stages of rock failure – ranging from pore initiation to fragmentation and segmentation – were identified, revealing a progressive transition from microstructural alteration to macroscopic fracturing. A customized image analysis framework was employed to asses subsurface crack patterns, qualitatively and quantitatively with high fidelity, offering a robust tool for damage quantification. The results underscore the potential of controlled continual laser pulsing as a reliable method for targeted rock disintegration and highlight the role of image-based evaluation in advancing the mechanistic understanding of laser-rock interaction. These findings are expected to contribute positively for the development of next-generation rock-breaking and excavation technologies.</div></div>","PeriodicalId":56008,"journal":{"name":"Geomechanics for Energy and the Environment","volume":"44 ","pages":"Article 100741"},"PeriodicalIF":3.7,"publicationDate":"2025-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145158604","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":"Post-wildfire soil hydrophobicity and slope erosion remediation by applying environmentally friendly modifiers","authors":"Wenpei Ma ,&nbsp;Henry McKlin ,&nbsp;Russell Chan ,&nbsp;Caitlin Kim ,&nbsp;Teagan DePoint-Spang ,&nbsp;Ingrid Tomac","doi":"10.1016/j.gete.2025.100740","DOIUrl":"10.1016/j.gete.2025.100740","url":null,"abstract":"<div><div>This paper investigates the use of environmentally friendly remediation materials and techniques for rain-induced post-wildfire soil erosion on burned slopes. During wildfires, vegetation and organic matter combust and release hydrophobic chemicals on soil grains. Hydrophobicity reduces the water infiltration rate, prolongs the wetting process, increases erosion, and causes severe debris flows over watersheds. This comparative study presents the most effective approaches for mitigating hydrophobicity effects through environmentally friendly biopolymers and surfactants. Experimental techniques evaluate the dynamics of water drop penetration into treated and untreated soil, downhill water drop mobility, and erosion. The waterdrop contact angle measurements indicate that biopolymer Xanthan Gum (XG) slightly reduces hydrophobicity, whereas surfactant Sodium Cocoyl Isethionate (SCI) reduces it by a factor of a thousand. In addition, SCI can decrease slope erosion at low-inclined and moderate-inclined slopes. Sands' infiltration rates (IR) are very fast due to high permeability in normal conditions; however, surface hydrophobicity significantly reduces IR. Results from artificially treated extremely water-repellent samples of mixed sand show a six orders of magnitude decrease in IR. Then, after treatments XG and SCI modifiers, the IR increased by an order of magnitude after the XG treatments, and by four orders of magnitude under SCI treatment. Although XG is wettable and attractive to water, the crust and webs it forms between sand particles prevent effective water infiltration. Mild slopes exhibit similar IR rates as horizontal surfaces for all the cases; however, steeper slopes reduce IR for treated hydrophobic soils because they allow for downhill motion of water that is faster relative to the infiltration speed.</div></div>","PeriodicalId":56008,"journal":{"name":"Geomechanics for Energy and the Environment","volume":"44 ","pages":"Article 100740"},"PeriodicalIF":3.7,"publicationDate":"2025-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145106906","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":"Rock physics and fracture characterization of the Deadwood Formation, Williston Basin: Insights into geothermal resource development","authors":"Moones Alamooti,&nbsp;Shane Namie","doi":"10.1016/j.gete.2025.100737","DOIUrl":"10.1016/j.gete.2025.100737","url":null,"abstract":"<div><div>Sedimentary basin geothermal systems face critical characterization challenges from complex reservoir heterogeneity that traditional assessment methods inadequately address. This study develops an integrated petrophysical-structural framework for the Deadwood Formation in North Dakota's Williston Basin using advanced rock physics modeling and statistical fracture analysis. We employed Differential Effective Medium theory for bimodal pore structures (macropores 10–100 micrometers, micropores &lt;1 micrometer), Kuster-Toksöz analysis for fracture-induced anisotropy with aspect ratios 0.001–1.0, and Gassmann fluid substitution with empirically constrained parameters. Formation Micro-Imager logs at 5 millimeter resolution enabled statistical characterization of 847 fractures across 450 feet, with uncertainty quantification through Monte Carlo simulation. Results demonstrate exceptional geothermal potential with a validated gradient of 34.6°C/km, significantly exceeding typical sedimentary basin values of 25–30°C/km, achieving 160–162°C at economically viable depths of 3.0–3.1 kilometers. Fracture networks follow log-normal distributions with volumetric intensities of 0.07–2.82 fractures/ft³ and a coefficient of variation of 79 %, requiring stochastic modeling approaches. Rock physics modeling successfully discriminates reservoir zones with correlation coefficients exceeding 0.87, identifying Members B and A as optimal targets. Economic analysis demonstrates commercial viability with levelized electricity costs of 8.7 cents per kilowatt-hour (confidence interval: 6.1–12.4), competitive with renewable alternatives. The superior depth-to-temperature ratio of 18.9–19.4 m per degree Celsius provides 25–45 % cost advantages over typical sedimentary prospects. Parameter bounds were constrained by core and log data (φ = 0.08 – 0.18; K_s = 37 – 43 GPa; K-f = 0.02 – 2.3 GPa across steam-brine scenarios), with dry-frame moduli from DEM directly feeding Gassman substitution. This integrated framework advances sedimentary geothermal assessment while establishing replicable protocols for global application, contributing to sustainable energy transition goals.</div></div>","PeriodicalId":56008,"journal":{"name":"Geomechanics for Energy and the Environment","volume":"44 ","pages":"Article 100737"},"PeriodicalIF":3.7,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145106797","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":"Investigation on mechanical response and fracture behavior of initially damaged shale based on multi-level PB-GBM method","authors":"Jianping Zuo ,&nbsp;Bo Lei ,&nbsp;Genshui Wu ,&nbsp;Haiyan Liu ,&nbsp;Massimo Coli","doi":"10.1016/j.gete.2025.100738","DOIUrl":"10.1016/j.gete.2025.100738","url":null,"abstract":"<div><div>Research on the failure behavior of Longmaxi shale is vital for shale reservoir reconstruction. Shale inherently contains some initial micro-cracks, which significantly affect its strength and failure behavior. In this paper, a refined boundary multi-level parallel bonded grain-based model (multi-level PB-GBM) in Particle Flow Code (PFC2D) was developed, and the effect of inherent initial damage on shale strength and failure behavior was quantitatively investigated. The results showed that inherent initial damage significantly influences the failure pattern and mechanical properties of shale. The newly generated cracks of the initially damaged samples are significantly self-organized compared with those of the undamaged samples, indicating that the inherent initial damaged cracks induce the orientation and aggregation of micro-cracks. High initially damaged samples mainly demonstrate by splitting-shear coupled fracture as a result of the co-evolution of primary and secondary micro-cracks. Generally, rock strength gradually decreases as the initial damage increases. When the inherent initial damage within the sample is low, the rock strength is greatly influenced by confining pressure, whereas when the initial damage is high enough, the initial damage contributes more to the rock strength.</div></div>","PeriodicalId":56008,"journal":{"name":"Geomechanics for Energy and the Environment","volume":"44 ","pages":"Article 100738"},"PeriodicalIF":3.7,"publicationDate":"2025-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145106909","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":"A three-dimensional fractional elastoplastic constitutive model for rocks within ductile domain","authors":"Jiacun Liu ,&nbsp;Junjie Xiao ,&nbsp;Ying Xu ,&nbsp;Xing Li ,&nbsp;Kaiwen Xia ,&nbsp;Gang Han","doi":"10.1016/j.gete.2025.100736","DOIUrl":"10.1016/j.gete.2025.100736","url":null,"abstract":"<div><div>Under the influence of high three-dimensional geostress, rocks transition into the ductile domain, undergoing continuous plastic hardening and volumetric contraction. Accurately describing the three-dimensional anisotropic deformation of rocks within ductile domain is of great significance for deep underground engineering. Therefore, a three-dimensional fractional elastoplastic constitutive within ductile domain is proposed in this study, including yield function and fractional flow rule. The ductile yield function is based on the modified Mohr-Coulomb criterion and generalized Matsuoka-Nakai deviatoric function. The deviatoric stress of yield surface is negatively correlated to hydrostatic pressure, but positively correlated to Lode angle. The yield surfaces in both meridian and deviatoric planes evolve with the plastic internal variable, accurately capturing the stress state during hardening. Two different fractional orders are used to control the plastic flow direction within meridian and deviatoric planes, represented by dilation angle and plastic deflection angle, respectively. These fractional orders are determined based on the relationship between plastic shear strain and volumetric strain, and they vary with the plastic internal variable, effectively capturing the plastic flow direction throughout hardening. The proposed model is validated using green sandstone data from hydrostatic compression and true-triaxial tests. The effect of fractional orders on the dilation angle and plastic deflection angle is discussed. Under the influence of fractional orders, both dilation angle and plastic deflection angle range from <span><math><msup><mrow><mn>0</mn></mrow><mo>∘</mo></msup></math></span> to <span><math><mrow><mo>−</mo><msup><mrow><mn>90</mn></mrow><mo>∘</mo></msup></mrow></math></span>. Besides, a comparison between the non-orthogonality and orthogonality flow rules is made. These results indicate that the fractional flow rule significantly improves the applicability and accuracy of constitutive model.</div></div>","PeriodicalId":56008,"journal":{"name":"Geomechanics for Energy and the Environment","volume":"44 ","pages":"Article 100736"},"PeriodicalIF":3.7,"publicationDate":"2025-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145005361","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":"MICP-enhanced wind erosion resistance of desert sand: process parameter optimization and microstructural mechanism","authors":"Jian Xu ,&nbsp;Liangkun Ding ,&nbsp;Zihan Li ,&nbsp;Jiayuan Li","doi":"10.1016/j.gete.2025.100735","DOIUrl":"10.1016/j.gete.2025.100735","url":null,"abstract":"<div><div>This study employed the microbially induced calcium carbonate precipitation (MICP) technique to investigate the mechanism of desert sand stabilization through a multiscale approach, ranging from macro to micro levels. A multi-objective optimization model was created to enhance surface strength, CaCO₃ content, and solidified layer thickness using a comprehensive analysis of multiple factors. The solidification effect was validated with wind tunnel and water retention tests. Microstructural mechanisms were examined through XRD, SEM, and PCAS. Results indicate that the optimum parameters for MICP technology are the 1:2.12 mix ratio, the 1.895 mol/L cementation solution concentration, and 4 treatment cycles. There was also a clear correlation between the performance indexes after solidification. The parameters optimized by the response surface method were essentially the same as those obtained from the experiments, with a difference of less than 5 % between the repeated test results and the optimized results. Under conditions of high <em>CSC</em> (single treatment cycle) or low <em>CSC</em> (multiple treatment cycles), MICP-treated desert sands can achieve highly efficient sand fixation and long-lasting water retention. Microanalysis revealed that increasing <em>CSC</em> and <em>T</em>_<em>c</em> altered the mode of particle contact from point to surface, and a significant negative correlation was observed between pore parameters and surface strength. This proves that it improves the water retention and mechanical strength of desert sand.</div></div>","PeriodicalId":56008,"journal":{"name":"Geomechanics for Energy and the Environment","volume":"43 ","pages":"Article 100735"},"PeriodicalIF":3.7,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144925645","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":"Accelerating the Energy Transition with Energy Geotechnics: editorial","authors":"Philip J. Vardon ,&nbsp;Anne-Catherine Dieudonné ,&nbsp;John. S. McCartney ,&nbsp;Jean-Michel Pereira ,&nbsp;David Smeulders ,&nbsp;Guillermo Narsilio","doi":"10.1016/j.gete.2025.100706","DOIUrl":"10.1016/j.gete.2025.100706","url":null,"abstract":"","PeriodicalId":56008,"journal":{"name":"Geomechanics for Energy and the Environment","volume":"43 ","pages":"Article 100706"},"PeriodicalIF":3.7,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145048917","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}