Engineering Geology最新文献

{"title":"In-situ and experimental investigations of the failure characteristics of surrounding rock through granites with biotite interlayers in a tunnel","authors":"Wei Zhang ,&nbsp;Lei Hu ,&nbsp;Zhi-Bin Yao ,&nbsp;Yong-Run Xiong ,&nbsp;Jun Zhao ,&nbsp;Tao Ma ,&nbsp;Song Chen ,&nbsp;Zhe Xu","doi":"10.1016/j.enggeo.2024.107816","DOIUrl":"10.1016/j.enggeo.2024.107816","url":null,"abstract":"<div><div>Significant differences in the failure characteristics of surrounding rocks caused by complex lithologies and geological conditions have been observed in deep tunnels. In this work, a failure involving rockburst and collapse observed in a deep tunnel excavated by a tunnel boring machine (TBM) was introduced. The in-situ failure characteristics of granite with biotite interlayers with different biotite contents and particle sizes were studied via field investigations and mineral composition analysis. The microseismic activity characteristics and fracture mechanisms at different failure zones were analyzed. The strength, failure, acoustic emission (AE) and brittleness characteristics of these types of granites were studied via true triaxial compression tests. The results showed that the biotite granite with biotite interlayers is prone to rockburst and that high-intensity rockburst may occur with less energy than in the intact biotite granite area. The rock fractures are mainly tensile failures, even in the biotite interlayer area. In contrast, the feldspar biotite schist surrounding rock is prone to collapse regardless of whether it contains biotite interlayers. The number of microseismic events during this collapse is relatively small, but the energy is relatively high compared with that of the rockburst at the biotite granite with biotite interlayers. The true triaxial strength and brittleness of the granite samples gradually decrease with increasing biotite content. The biotite granite exhibits very high AE activity, so it is prone to rockburst. The AE activity of medium-coarse grained monzogranite is relatively low; thus, both rockburst and collapse may occur. The strength, brittleness, and AE activity of feldspar biotite schist are very low, and its failure mode is mainly collapse. This study elucidates the typical failure modes and characteristics of different granites with biotite interlayers and can provide a basis and guidance for targeted failure warning and mitigation in tunnels with similar lithologies and geological conditions.</div></div>","PeriodicalId":11567,"journal":{"name":"Engineering Geology","volume":"343 ","pages":"Article 107816"},"PeriodicalIF":6.9,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142660182","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evolution characteristics of mining-induced fractures in overburden strata under close-multi coal seams mining based on optical fiber monitoring","authors":"Yiwei Ren ,&nbsp;Qiang Yuan ,&nbsp;Jie Chen ,&nbsp;Ze Wang ,&nbsp;Dingding Zhang ,&nbsp;Shujun Li","doi":"10.1016/j.enggeo.2024.107802","DOIUrl":"10.1016/j.enggeo.2024.107802","url":null,"abstract":"<div><div>Large-scale mining fractures resulting from repeated mining are a major cause of surface water loss in the northern Shaanxi mining area, China. Accurately detecting the evolution of mining-induced fractures is crucial for addressing the fragile ecological environment and ensuring coalmine production safety in this area. This study focuses on the close-multi coal seams mining at the Ningtiaota coalmine, northern Shaanxi, China, investigating the failure types of overburden rock, the evolution of mining-induced fractures, and the height of fracture zones. The results indicate that the failure type of overburden strata transforms from a “trapezoid shape” to an “overlapping trapezoid shape”, with the fracture zone height extending from 64.5 m to 158.5 m due to the superposition of secondary mining. Furthermore, the evolution characteristics of mining-induced fractures shift from a “three-stage and three-step” model to a “three-stage and two-step” model. A characterization model of overburden deformation based on optical fiber sensing is proposed to effectively describe the strain distribution characteristics of overburden failure. This model reveals the spatiotemporal evolution of overburden deformation from the perspective of “horizontal three areas and vertical three zones”, enabling real-time characterization of overburden deformation. The results demonstrate a relative error of less than 5.0 % between optical fiber monitoring and other methods, excluding theoretical calculations. This study offers a technical solution for detecting mining-induced fractures in the northern Shaanxi mining area and holds significant implications for broader studies of overburden deformation and failure under repeated mining.</div></div>","PeriodicalId":11567,"journal":{"name":"Engineering Geology","volume":"343 ","pages":"Article 107802"},"PeriodicalIF":6.9,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142660647","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluating the chain of uncertainties in the 3D geological modelling workflow","authors":"A.S. Høyer,&nbsp;P.B.E. Sandersen,&nbsp;L.T. Andersen,&nbsp;R.B. Madsen,&nbsp;M.H. Mortensen,&nbsp;I. Møller","doi":"10.1016/j.enggeo.2024.107792","DOIUrl":"10.1016/j.enggeo.2024.107792","url":null,"abstract":"<div><div>Geological models are used for a range of applications relevant for engineering geology and the demands for reliable geological models with realistic uncertainty assessments are therefore increasing. The geological modelling workflow is divided into multiple steps, each associated with uncertainties. Often however, many of these sources of uncertainty are overlooked, which may lead to an underestimation of the uncertainties of the final model. The main reason is that most of the steps in the geological modelling workflow are subjective to some degree. Thus, the possible sources of uncertainty in geological modelling are theoretically infinite, and without a trustworthy conceptual model to outline the expected geological structures and lithologies, the uncertainty assessment of the resulting model will likewise be unreliable. In this paper, we describe the chain of uncertainties in the geological modelling workflow and showcase some of the most important sources of uncertainties through practical modelling examples from two different model areas. The paper also presents and discuss a method to conduct qualitative uncertainty assessment, which is conducted by the modeler and based on expert evaluation and prioritization of the different sources of uncertainty. The practical use of the uncertainty assessment method is exemplified in the last two examples, representing a local-scale and a large-scale model, respectively. All four examples are from Danish geological models that have been constructed as interpretation-based layer-models. However, the considerations regarding the uncertainties in the chain of the geological modelling workflow are useful regardless of the modelling method.</div></div>","PeriodicalId":11567,"journal":{"name":"Engineering Geology","volume":"343 ","pages":"Article 107792"},"PeriodicalIF":6.9,"publicationDate":"2024-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142660744","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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":"Thermal and mechanical impact of artificial ground-freezing on deep excavation stability in Nakdong River Deltaic deposits","authors":"Sangyeong Park ,&nbsp;Youngjin Son ,&nbsp;Jae-guem Kim ,&nbsp;Dong-Jin Won ,&nbsp;Hangseok Choi","doi":"10.1016/j.enggeo.2024.107796","DOIUrl":"10.1016/j.enggeo.2024.107796","url":null,"abstract":"<div><div>This paper presents a case study of deep excavation using the artificial ground freezing (AGF) method for tunnel restoration work in the Nakdong River deltaic deposits. The study involved detailed construction monitoring and data analysis to assess the thermal and mechanical impacts on surrounding ground and underground structures. Factors influencing heat transfer were identified and evaluated for their effect on ground temperature distribution. The excavation and frost expansion of the ground led to unique lateral deformation of the diaphragm wall. However, the frozen soil effectively resisted earth pressure and suppressed deformation of the wall. The axial stress applied to the braced strut was closely related to the deformation of the diaphragm wall and was influenced by both excavation-induced and frost-expansion pressures. Boreholes near the frozen soil functioned as stress-relief holes, enhancing excavation stability. These comprehensive findings enhance the understanding of AGF techniques and their impact on complex deltaic geological conditions and adjacent structures.</div></div>","PeriodicalId":11567,"journal":{"name":"Engineering Geology","volume":"343 ","pages":"Article 107796"},"PeriodicalIF":6.9,"publicationDate":"2024-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142660745","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Novel method to estimate horizontal variability of shear wave velocity through multichannel analysis of surface waves","authors":"Yen-Hsiang Chang ,&nbsp;Chi-Chin Tsai ,&nbsp;Louis Ge ,&nbsp;Duhee Park","doi":"10.1016/j.enggeo.2024.107799","DOIUrl":"10.1016/j.enggeo.2024.107799","url":null,"abstract":"<div><div>Scale of fluctuations (SOFs) of spatially variable soil properties have been regarded as one of the important parameters for performing reliability-based design in geotechnical engineering. However, the information required to estimate the SOFs in practice is limited, especially in the horizontal direction. In this study, the potential use of Multichannel Analysis of Surface Waves (MASW) to estimate the SOFs of shear wave velocity (V_S) in horizontal direction is investigated through a series of numerical investigations. 2D random field models with a vertically increasing trend of V_S were first simulated with different levels of variability controlled by the coefficient of variation (COV) and SOF. Afterwards, a large number of numerical MASW tests were performed using a 2D finite difference method, where the survey lines were progressively shifted. Results show that the COV of V_S can be determined from the scatter of the dispersion curves, whereas the horizontal SOF of V_S can be appropriately estimated from the phase velocity profile presented in the wavelength form. Additionally, in-situ MASW tests were conducted to estimate the horizontal SOF, and the obtained results align with those estimated by different methods. It is highlighted that the accuracy of the estimation depends on survey length. The interpretation using a long array reflects an averaged site condition of the survey area, thus losing the variability information. Favorable predictions are produced when survey length is shorter than 1.0 SOF. However, it should be noted that use of short survey length may limit the depth of investigation.</div></div>","PeriodicalId":11567,"journal":{"name":"Engineering Geology","volume":"343 ","pages":"Article 107799"},"PeriodicalIF":6.9,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142660739","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimized binarization algorithm-based method for the image recognition and characterization of explosion damage in rock masses","authors":"Jiazheng Gao ,&nbsp;Yongsheng He ,&nbsp;Yeqing Chen ,&nbsp;Zhenqing Wang ,&nbsp;Chunhai Li","doi":"10.1016/j.enggeo.2024.107787","DOIUrl":"10.1016/j.enggeo.2024.107787","url":null,"abstract":"<div><div>The quantitative analysis of rock mass damage is crucial in fields such as engineering geology, disaster prevention, mining, geotechnical engineering, and structural engineering. With the advancement and application of noncontact measurement technologies and fractal theory, image-based damage identification methods are gaining increasing importance. This paper presents an optimized binarization algorithm for identifying and characterizing damage zones in granite explosion images. The method involves filtering, mathematical morphology operations, and connectivity recognition to effectively remove background noise while preserving clear boundaries of the damaged areas. It accurately captures the explosion damage in granite, both in terms of damage morphology and characteristic parameters. Additionally, the coefficient of agreement (<em>COA</em>) is introduced to quantitatively assess the accuracy of different methods in identifying damaged areas. The experimental results show that, compared with commonly used methods such as Otsu's method, Bernsen's algorithm, Niblack's algorithm, Sauvola's algorithm, and the K-means image clustering algorithm, the proposed method performs better in terms of identification accuracy and parameter agreement, achieving <em>COA</em> values near 1 across diverse experimental environments. Furthermore, the proposed method excels in handling uneven lighting, mitigating interference from rock surface textures and explosion carbonization zones, and demonstrates significant robustness in complex scenarios. The findings of this paper provide insights into the integration of engineering geology and computer vision technology. They offer valuable references for damage identification in excavation damage zones (EDZs), geological disaster evaluation, and structural damage warning systems.</div></div>","PeriodicalId":11567,"journal":{"name":"Engineering Geology","volume":"343 ","pages":"Article 107787"},"PeriodicalIF":6.9,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142660742","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Injection-induced seismic moment in layered rock formations","authors":"Dazhao Lu,&nbsp;Wei Wu","doi":"10.1016/j.enggeo.2024.107793","DOIUrl":"10.1016/j.enggeo.2024.107793","url":null,"abstract":"<div><div>Appropriate estimation of seismic moment release during fluid injection is critical to mitigate the risk of induced seismic hazards and to guide safe operation in the geo-energy industry. However, the present single-layer models overlook the contributions of fault slip in different rock layers to the seismic moment release. Here we report an analytical model incorporating a multiple-layer function to predict the injection-induced seismic moment in layered rock formations. This model is established based on fault slip triggered by aseismic motion, particularly considering the locations of aseismic slip front and fluid diffusion front on a seismogenic fault in relative to the layer interface. We compare the maximum seismic moment obtained from our model to those estimated from three single-layer models and those measured from eleven field cases. The results highlight possible underestimation of the maximum seismic moment using the single-layer models in the layered rock formations. We also emphasize that a proper selection of layer model is significant to reasonably assess the seismic moment release. Lastly, we apply both the single-layer and double-layer models to predict the maximum seismic moment of the 5 February 2019 <span><math><msub><mi>M</mi><mi>w</mi></msub></math></span> 4.0 earthquake in the Weiyuan Shale Gas Field in Sichuan, China. The engineering application further confirms the necessity of using the double-layer model in the layered rock formations. Additionally, the assessment of amplification factors for fault segments provides a better understanding of induced seismic hazards in different rock layers and possibly guides the safety threshold of injection rate during fluid injection.</div></div>","PeriodicalId":11567,"journal":{"name":"Engineering Geology","volume":"343 ","pages":"Article 107793"},"PeriodicalIF":6.9,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142660736","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantitative risk assessment of road exposed to landslide: A novel framework combining numerical modeling and complex network theory","authors":"Shu Zhou ,&nbsp;Yu Huang ,&nbsp;Zhen Guo ,&nbsp;Chaojun Ouyang","doi":"10.1016/j.enggeo.2024.107794","DOIUrl":"10.1016/j.enggeo.2024.107794","url":null,"abstract":"<div><div>The quantitative analysis of the landslide risk posed to road networks is a challenging task owing to the uncertainty involved both in the potential landslide hazard and the road value. To address this challenge, this paper proposes a novel framework to assess the road risk in quantitative terms. The landslide hazard is assessed using the depth-integrated method with consideration of the landslide size probability and initial conditions. The potential direct losses associated with road disruption are determined by exposure analysis in a geographical information system. The indirect losses of the road caused by the landslide were analyzed through complex network theory with consideration to regional socioeconomic development and the time required for road restoration. The proposed framework was used to assess the road risk posed by the Chunchangba landslide, Xiaojin County, China. The results show that the volume size probability of landslides in the Xiaojin area could be assessed using the function <span><math><mi>P</mi><mfenced><mi>V</mi></mfenced><mo>=</mo><mn>1</mn><mo>/</mo><mfenced><mrow><mn>1</mn><mo>+</mo><mn>3.583</mn><mo>×</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>5</mn></mrow></msup><msup><mi>V</mi><mrow><mn>2</mn><mo>×</mo><mn>0.391</mn></mrow></msup></mrow></mfenced></math></span>. The depth-integrated method based hazards assessment results show the maximum impact area of the Chunchangba landslide reached 0.383 km², and the landslide has a high probability of damaging the lower road and forming a barrier lake. The losses associated with road disruption caused by the landslide were estimated. The maximum direct losses reached 293,100 USD, while indirect losses reached 423,800 USD, which has the same importance as direct losses. The risk curve reveals that the maximum probability of the road risk associated with the Chunchangba landslide is 0.0175 %, 0.0189 %, 0.0190 %, and 0.0191 % for the time interval of 5, 10, 20, and 50 years, respectively, with losses of 0.177 million USD/year. The regional disaster mitigation strategy is analyzed based on quantitative risk analysis. The results show that a new 2.7 km road on the mountain opposite the Chunchangba landslide can reduce indirect losses by approximately 300 times. The findings of this study contribute to sustainable development and landslide risk management in mountainous areas.</div></div>","PeriodicalId":11567,"journal":{"name":"Engineering Geology","volume":"343 ","pages":"Article 107794"},"PeriodicalIF":6.9,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142660738","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermo-hydro-mechanical modelling of the heterogeneous subsidence and swelling in the desiccation cracked clayey strata","authors":"Hamed Sadeghi ,&nbsp;Milad Jabbarzadeh ,&nbsp;Saeed Tourchi","doi":"10.1016/j.enggeo.2024.107798","DOIUrl":"10.1016/j.enggeo.2024.107798","url":null,"abstract":"<div><div>Soil desiccation cracking as a consequence of severe environmental changes alters soil deformation mechanisms significantly. Therefore, this study aims to explore the effect of crack characteristics and environmental conditions on the heterogeneous deformation of desiccation-cracked soils using thermo-hydro-mechanical analyses. The model framework consists of balance equations, thermal, hydraulic, and mechanical constitutive equations, while the model scenarios were determined based on statistical analyses. The meteorological record of Qom city was used for three years, from 2015 to 2017, to capture long-term behaviour under wetting-drying cycles. Findings revealed that cracks extend the deformation range, potentially up to six times, with variation based on crack dimensions and spacing. Notably, narrower cracks experienced more pronounced deformation than wider ones. The cracked soil with a crack depth of 2.5 m showed 1.5 times higher swelling and subsidence than crack depth of 1 m. Furthermore, the wider cracks indicated a lower rate of increase in their dimensions compared to the initial state during drying. The investigation also highlights the mechanisms of soil surface shape due to swelling and shrinkage, resulting in concave and convex surfaces, respectively. The results provide new perspectives on the behaviour of fine-grained deposits in arid to semi-arid climates with deep groundwater levels.</div></div>","PeriodicalId":11567,"journal":{"name":"Engineering Geology","volume":"343 ","pages":"Article 107798"},"PeriodicalIF":6.9,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142660740","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Large-scale geohazards risk of submarine landslides considering the subsea cables vulnerability: A case study from the northern continental slopes of South China Sea","authors":"Defeng Zheng ,&nbsp;Qingkang Fang ,&nbsp;Deyu Lei ,&nbsp;Zehao Wang ,&nbsp;Chenglin Yan ,&nbsp;Ze Rong","doi":"10.1016/j.enggeo.2024.107788","DOIUrl":"10.1016/j.enggeo.2024.107788","url":null,"abstract":"<div><div>Submarine landslides pose significant threats to subsea cables distributed on the global seabed. However, regional scale risk assessment of landslide geohazards is rarely reported. This study introduces a methodology for regional-scale geohazard risk prediction of submarine landslides, focusing on the northern continental slopes of the South China Sea. Initially, the study employed the infinite-slope method to calculate safety factors for typical submarine slopes. Addressing uncertainties in geotechnical and seismic parameters, Monte Carlo simulations determine slope failure probabilities. Using kriging interpolation, localized failure probabilities are extrapolated to regional scales, establishing a spatiotemporal distribution method for large-scale geohazard susceptibility. Hazard levels are subsequently determined considering the volumes of potential landslides. The density of subsea cables is used as a vulnerability factor to guide the regional-scale assessment of cable vulnerability. Finally, integrating vulnerability with hazard levels provides a comprehensive assessment of landslide-induced large-scale geohazard risks. The findings highlight elevated geohazard risks in the Taiwan Bank slope segment, moderate risks in the Zhujiang Valley and Shenhu slope segments, with lower risks in other areas.</div></div>","PeriodicalId":11567,"journal":{"name":"Engineering Geology","volume":"343 ","pages":"Article 107788"},"PeriodicalIF":6.9,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142659632","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}