检索结果-南通市图书馆

Stress tensor determination by modified hydraulic tests on pre-existing fractures:Method and stress constraints

Journal of rock mechanics and geotechnical Engineering 2024年第5期16卷 1637-1648页

作者： Guiyun Gao Chenghu Wang Ke Gao National Institute of Natural hazards Ministry of Emergency Management of ChinaBeijing100085China Beijing Engineering Research center of Earthquake Observation Beijing100085China Key Laboratory of Compound and Chained Natural hazards Dynamics Ministry of Emergency Management of ChinaBeijing100085China Department of Earth and Space Sciences Southern University of Science and TechnologyShenzhen518055China

The hydraulic testing of pre-existing fractures(HTPF)is one of the most promising in situ stress measurement methods,particularly for three-dimensional stress tensor ***,the stress tensor determination based on the HTPF method requires at least six tests or a minimum of 14-15 tests(under different conditions)for reliable *** this study,we modified the HTPF method by considering the shear stress on each pre-existing fracture,which increased the number of equations for the stress tensor determination and decreased the number of tests *** shear stresses were attributed to different fractures by random sampling;therefore,the stress tensors were obtained by searching for the optimal solution using the least squares criterion based on the Monte Carlo ***,we constrained the stress tensor based on the tensile strength criterion,compressive strength criterion,and vertical stress *** inverted stress tensors were presented and analyzed based on the tensorial nature of the stress using the Euclidean mean stress *** stress-measurement campaigns in Weifang(Shandong Province,China)and Mercantour road tunnel(France)were implemented to highlight the validity and efficiency of the modified HTPF(M-HTPF)*** results showed that the M-HTPF method can be applied for stress tensor inversion using only three to four tests on pre-existing fractures,neglecting the stress *** inversion results were confined to relatively small distribution dispersions and were significantly reliable and stable due to the shear stresses on the fractures and the stress constraints *** M-HTPF method is highly feasible and efficient for complete stress tensor determination in a single borehole.

关键词： Stress tensor Hydraulic tests on pre-existing fractures Mean stress Stress constraint Hydraulic fracturing

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Experimental study on workability and permeability of sandy soils conditioned with thickened foam

引用

Journal of rock mechanics and geotechnical Engineering 2024年第2期16卷 532-544页

作者： Zhiyao Feng Shuying Wang Tongming Qu Xiangcou Zheng Fanlin Ling School of Civil Engineering Central South UniversityChangsha410075China Tunnel and Underground Engineering Research center Central South UniversityChangsha410075China Department of Civil and Environmental Engineering The Hong Kong University of Science and TechnologyClearwater BayKowloon999077Hong KongChina geo-Engineering Section Delft University of TechnologyDelft999025Netherlands

Water spewing and muck plugging often occur during earth pressure balance(EPB)shield machines tunnelling in water-rich sandy strata,even though the conventional foam has been employed to condition sandy *** this study,a novel thickened foaming agent suitable for EPB shield tunnelling in water-rich sandy strata is *** contrast to conventional foam-conditioned sands,the thickened foam-conditioned sand has a low permeability due to the consistent filling of soil pores with the thickened foam,and the initial permeability coefficient decreases by approximately two orders of *** also exhibits a suitable workability,which is attributed to the enhanced capability of the thickened foam to condition sandy *** addition,the effect of concentration on the stability of the foam is explained by the Gibbs-Marangoni effect,and conditioning mechanisms for the thickened foam on sands are discussed from the evolution of foam bubbles.

关键词： Earth pressure balance(EPB)shield Thickened foam Foam-conditioned sand Permeability Workability

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Physics-informed optimization for a data-driven approach in landslide susceptibility evaluation

引用

Journal of rock mechanics and geotechnical Engineering 2024年第8期16卷 3192-3205页

作者： Songlin Liu Luqi Wang Wengang Zhang Weixin Sun Yunhao Wang Jianping Liu School of Civil Engineering Chongqing UniversityChongqing400045China Key Laboratory of New Technology for Construction of Cities in Mountain Area Chongqing UniversityMinistry of EducationChongqing400045China National Joint Engineering Research center of geohazards Prevention in the Reservoir Areas Chongqing UniversityChongqing400045China Chongqing Field Scientific Observation Station for Landslide hazards in Three Gorges Reservoir Area Chongqing UniversityChongqing400045China Chongqing Mingfeng Construction Engineering Co. LtdChongqing405800China

Landslide susceptibility mapping is an integral part of geological hazard ***,the emphasis of many studies has been on data-driven models,notably those derived from machine learning,owing to their aptitude for tackling complex non-linear ***,the prevailing models often disregard qualitative research,leading to limited interpretability and mistakes in extracting negative samples,*** non-landslide *** this study,Scoops 3D(a three-dimensional slope stability analysis tool)was utilized to conduct a qualitative assessment of slope stability in the Yunyang section of the Three Gorges Reservoir *** depth of the bedrock was predicted utilizing a Convolutional Neural Network(CNN),incorporating local boreholes and building on the insights from prior *** Random Forest(RF)algorithm was subsequently used to execute a data-driven landslide susceptibility *** proposed methodology demonstrated a notable increase of 29.25%in the evaluation metric,the area under the receiver operating characteristic curve(ROC-AUC),outperforming the prevailing benchmark ***,the landslide susceptibility map generated by the proposed model demonstrated superior *** result not only validates the effectiveness of amalgamating mathematical and mechanistic insights for such analyses,but it also carries substantial academic and practical implications.

关键词： Physics-informed Machine learning Bedrock depth Scoops 3D Landslide susceptibility

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Thermo-hydro-poro-mechanical responses of a reservoir-induced landslide tracked by high-resolution fiber optic sensing nerves

引用

Journal of rock mechanics and geotechnical Engineering 2024年第3期16卷 1018-1032页

作者： Xiao Ye Hong-Hu Zhu Gang Cheng Hua-Fu Pei Bin Shi Luca Schenato Alessandro Pasuto School of Earth Sciences and Engineering Nanjing UniversityNanjing210023China School of Computer Science North China Institute of Science and Technology(National Safety Training Center of Coal Mines)Beijing101601China State Key Lab of Coastal and Offshore Engineering Department of Geotechnical EngineeringDalian University of TechnologyDalian116024China National Research Council-Research Institute for geo-Hydrological Protection(CNR-IRPI) Padova35127Italy Department of Information Engineering University of PadovaPadova35131Italy

Thermo-poro-mechanical responses along sliding zone/surface have been extensively ***,it has not been recognized that the potential contribution of other crucial engineering geological interfaces beyond the slip surface to progressive ***,we aim to investigate the subsurface multiphysics of reservoir landslides under two extreme hydrologic conditions(*** and dry),particularly within sliding *** on ultra-weak fiber Bragg grating(UWFBG)technology,we employ specialpurpose fiber optic sensing cables that can be implanted into boreholes as“nerves of the Earth”to collect data on soil temperature,water content,pore water pressure,and *** Xinpu landslide in the middle reach of the Three Gorges Reservoir Area in China was selected as a case study to establish a paradigm for in situ thermo-hydro-poro-mechanical *** UWFBG-based sensing cables were vertically buried in a 31 m-deep borehole at the foot of the landslide,with a resolution of 1 m except for the pressure *** reported field measurements covering the period 2021 and 2022 and produced the spatiotemporal profiles throughout the *** show that wet years are more likely to motivate landslide motions than dry *** annual thermally active layer of the landslide has a critical depth of roughly 9 m and might move downward in warmer *** dynamic groundwater table is located at depths of 9e15 m,where the peaked strain undergoes a periodical response of leap and withdrawal to annual hydrometeorological *** interface behaviors may support the interpretation of the contribution of reservoir regulation to slope stability,allowing us to correlate them to local damage events and potential global *** paper also offers a natural framework for interpreting thermo-hydro-poro-mechanical signatures from creeping reservoir bank slopes,which may form the basis for a landslide monitoring and early warning system.

关键词： Reservoir landslide Thermo-hydro-poro-mechanical response Ultra-weak fiber bragg grating(UWFBG) subsurface evolution Engineering geological interface geotechnical monitoring

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

High-Speed Ring Shear Tests to Study the Motion and Acceleration Processes of the Yingong Landslide

引用

Journal of Mountain Science 2015年第6期12卷 1534-1541页

作者： HU Ming-jian Pan Hua-li Zhu Chang-qi Wang Fa-wu State Key Laboratory of geomechanics and geotechnical Engineering Institute of rock and Soil mechanics Chinese Academy of Sciences Key Laboratory of Mountain hazards and Earth Surface Process Institute of Mountain hazards and Environment Chinese Academy of Sciences Research center on Natural Disaster Reduction Shimane University

In this paper, the motion and acceleration process, as well as the mechanism of a high speed and long run landslide are investigated by adopting high speed ring shear test and taking the landslide occurred at Yigong River in Bomi, Tibet on April 9, 2000 as the background. According to the motion characteristics of high-speed and long distance motion landside, the mechanism is studied under different conditions such as shear speed, consolidated drained and consolidated undrained status. Results show that high speed shearing process hinders and delays the dissipation of pore pressure, and drives pore water migrating to shear zone slowly. Both of water content and fine particle content at shear zone are obviously higher than those in other layers; and soil liquefaction occurs at shear zone in the saturated consolidated undrained ring shear tests. The effective internal friction angle of the consolidated undrained soil is much lower than that of the consolidated drained soil under ring shearing. The results also indicate that the shearing speed affecting the strength of soil to some extent. The higher the ring shearing speed is, the lower the strength of soil is. This investigation provides a preliminary interpretation of the mechanism of the motion and acceleration process of the Yigong landslide, occurred in Tibet in 2000.

关键词： Yigong landslide Ring shear tests Shear zone Liquefaction Strength

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Rainfall Threshold Calculation Method for Debris Flow Pre-Warning in Data-Poor Areas

引用

Journal of Earth Science 2013年第5期24卷 854-862页

作者：潘华利黄江成汪稔欧国强 Key Laboratory of Mountain hazards and Surface Progress Chinese Academy of Sciences Institute of Mountain hazards and Environment Chinese Academy of Sciences Asian International Rivers center Yunnan University State Key Laboratory of geomechanics and geotechnical Engineering Institute of rock and Soil mechanics Chinese Academy of Sciences

Debris flows are the one type of natural disaster that is most closely associated with hu- man activities. Debris flows are characterized as being widely distributed and frequently activated. Rainfall is an important component of debris flows and is the most active factor when debris flows oc- cur. Rainfall also determines the temporal and spatial distribution characteristics of the hazards. A reasonable rainfall threshold target is essential to ensuring the accuracy of debris flow pre-warning. Such a threshold is important for the study of the mechanisms of debris flow formation, predicting the characteristics of future activities and the design of prevention and engineering control measures. Most mountainous areas have little data regarding rainfall and hazards, especially in debris flow forming re- gions. Therefore, both the traditional demonstration method and frequency calculated method cannot satisfy the debris flow pre-warning requirements. This study presents the characteristics of pre-warning regions, included the rainfall, hydrologic and topographic conditions. An analogous area with abundant data and the same conditions as the pre-warning region was selected, and the rainfall threshold was calculated by proxy. This method resolved the problem of debris flow pre-warning in ar- eas lacking data and provided a new approach for debris flow pre-warning in mountainous areas.

关键词： rainfall threshold debris flow pre-warning calculation method data lack area.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Characterization and modeling of supercritical CO_(2)pulse pressures:Effects of activator mass and discharge plate thickness

Rock Mechanics Bulletin

引用

rock mechanics Bulletin 2024年第3期3卷 69-80页

作者： Erdi Abi Qifu Zeng Lin Fu Mingjing Jiang Jie Zhang Fayou Wu Mingwei Liu Yafeng Han National Engineering Research center for Inland Way Regulation Key Laboratory of Geological Hazards Mitigation of Mountainous Highway and WaterwayChongqing Jiaotong UniversityChongqing400074China School of CivilEngineering Suzhou University of Science and TechnologySuzhouJiangsu215009China State Key Laboratory for Disaster Reduction in Civil Engineering Tongji University Shanghai200092China School of Engineering Tibet UniversityLhasa850013China

Utilizing a bespoke CO_(2) phase transition pulse pressure experimental system,we conducted pulse pressure characterization tests across various activator masses,CO_(2) filling pressures,and energy discharge plate *** approach enabled us to ascertain the pulse pressure's response characteristics and variation patterns under diverse *** formula for calculating the peak supercritical CO_(2)pulse pressure was deduced by modeling the ultimate load calculation of the clamped circular plate,and then the time-course expression of the supercritical CO_(2)phase transition pulse pressure and energy was carried out by introducing the time factor and taking into account the parameters of the activator mass and the thickness of the energy discharging *** findings reveal a four-stage pressure evolution in the cracking tube during initiation:a gradual increase,a rapid spike,swift attenuation,and eventual negative pressure *** activator mass and discharge plate thickness critically influence the peak pressure's timing and ***,increased activator mass hastens peak pressure onset,while a thicker discharge plate amplifies *** errors between calculated and experimental values for peak supercritical CO_(2) phase transition pressure fall within5%–5%.Furthermore,the pressure peak and arrival time model demonstrates less than 10%error compared to experimental data,affirming its strong *** insights offer theoretical guidance for controlling phase transition pressure and optimizing energy in supercritical CO_(2) systems.

关键词： Supercritical CO_(2)phase transition Pressure-energy characterization test Pulsed peak pressure Pulsed pressure-energy time-course computational modeling

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Numerical simulation on the stability of rock slope based on an improved SPH Method

引用

Journal of Mountain Science 2021年第7期18卷 1937-1950页

作者： YU Shu-yang REN Xu-hua ZHANG Ji-xun WANG Hai-jun SUN Zhao-hua ZHOU Yu College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210098China School of Transportation and Civil Engineering Nantong UniversityNantong 226019China State Key Laboratory of Hydrology-Water Resource and Hydraulic Engineering Nanjing Hydraulic Research InstituteNanjing 210029China rock mechanics and geo-hazards center Shaoxing UniversityShaoxing 312000China

The presence of random fissures has a great impact on rock slope *** investigate the failure modes and stability of rock slopes containing different types of pre-existing fissures,the fracture mark ξ was introduced to improve the kernel function in the traditional smoothed particle dynamics(SPH) method,and a novel numerical method,the improved kernel of smoothed particle hydrodynamics(IKSPH),was proposed to realise the microscopic damage characteristics of *** ‘random fissure generating method' has been proposed for random fissure generation,and the gravity increase method has been embedded into the IKSPH program,thereby realising the stability analysis of rock slopes considering crack propagation processes.A typical steep rock slope is taken as a numerical simulation example considering the random distributions of preexisting fissures,and its failure modes as well as the stability under different conditions were *** results show that the failure processes of the rock slope contain propagations of microcracks and then macrocrack *** the fissure length is short,shallow collapse failure modes can be observed;when the fissure length is long,the deep layer slide occurs,and the slope stability decreases with an increase in fissure *** micro and macrocrack surfaces are basically consistent with pre-existing fissure angles,and the safety factor is the least at a fissure angle of 30°.The greater the fissure density,the greater the number of macrocracks,and the stability decreases with an increase in the number of pre-existing *** research results can provide some references for disaster protection and understanding the failure laws of rock ***,combining the geological survey results with the numerical simulations and developing a high-performance IKSPH program will be a future research direction.

关键词： IKSPH method Random fissures Gravity increase method High rock slopes Crack propagation Numerical simulation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

geo-engineered buffer capacity of two-layered absorbing system under the impact of rock avalanches based on Discrete Element Method

引用

Journal of Mountain Science 2016年第5期13卷 917-929页

作者： BI Yu-zhang HE Si-ming LI Xin-po WU Yong XU Qiang OUYANG Chao-jun SU Li-Jun WANG Hao Key Laboratory of Mountain hazards and Earth Surface Process Chinese Academy of Sciences Institute of Mountain hazards and Environment Chinese Academy of Sciences & Water Resources Ministry center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of Sciences State Key Laboratory of geo-Hazard Prevention and geo-Environment Protection Chengdu University of Technology College of Environment and Resources Fuzhou University

Many rock avalanches were triggered by the Wenchuan earthquake on May 12, 2008 in southwest China. Protection galleries covered with a single soil layer are usually used to protect against rockfall. Since one-layer protection galleries do not have sufficient buffer capacity, a two-layered absorbing system has been designed. This study aims to find whether an expanded poly-styrol （EPS） cushion, which is used in the soil-covered protection galleries for shock absorption, could be positioned under dynamic loadings. The dynamic impacts of the two-layered absorbing system under the conditions of rock avalanches are numerically simulated through a 2D discrete dement method. By selecting reasonable parameters, a series of numerical experiments were conducted to find the best combination for the two- layered absorbing system. The values of the EPS layer area as a percentage of the total area were set as 0% （Sl）, 22~ （S2）, and 70% （$3）. 22~ of the area of the EPS layer was found to be a reasonable value, and experiments were conducted to find the best position of the EPS layer in the two-layered absorbing system. The numerical results yield useful conclusions regarding the interaction between the impacting avalanches and the two-layered absorbing system. The soil layer can absorb the shock energy effectively and S2 （0.4-m thick EPS cushion covered with soil layer） is the most efficient combination, which can reduce the impact force, compared with the other combinations.

关键词： Discrete element method Buffer capacity Dynamic simulation Impact force Two-layered absorbing system

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Quantitative evaluation of rock brittle property based on energy evolution and its application in Three Gorges Reservoir area

引用

Journal of Earth Science 2022年

作者： Tao Wen Yankun Wang Huiming Tang School of geosciences， Yangtze University Three Gorges Research center for geo-hazards of Ministry of Education， China University of geosciences

Brittleness is of great significance for evaluating the mechanical properties of the slope rock in reservoir area and revealing the brittle failure mechanism of the rocks. Although a series of definitions of the brittleness and evaluation methods of brittleness index have been proposed， there is still lack of a widely recognized and remarkable standards in these aspects due to the differences in diagenetic process， depositional environment and mineral composition. The previous methods to quantitively estimate the rock brittleness based on energy balance analysis are summarized， which neglect multiple influencing factors of the rock brittleness， such as the weight of pre-peak or post-peak mechanical behaviors on the prediction performance of the brittleness index. Based on the typical curves about stress and strain， the relationships between the brittle failure behaviors and the energy evolutions are comprehensively analyzed， then a new method for assessing the brittleness is proposed. Based on pre-peak brittleness index to represent brittle property at pre-peak stage and post-peak brittleness index to determine brittle characteristic at post-peak stage， a new brittleness index is established by additive synthesis method in consideration of the weight of brittleness indexes before and after peak strength， and either of the two brittleness indexes can be punished or compensated by setting different parameter values. The results indicate that the proposed brittleness index can represent the brittle change laws for different rock types when α≤0.5， β≥0.5. When evaluating the brittleness of the slope rock in Three Gorges Reservoir (TGR) area， the results present that the rock brittleness in the slope affects the stability of the slope. Therefore， the novel evaluation method can provide reliable results， so the proposed brittleness index considering the energy evolution can be applied to assess the brittle property in the reservoir bank project.

关键词：

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：