检索结果-南通市图书馆

Effect of stress paths on failure mechanism and progressive damage of hard-brittle rock

Journal of Mountain Science 2021年第9期18卷 2486-2502页

作者： CHEN Zi-quan HE Chuan HU Xiong-yu MA Chun-chi key laboratory of Transportation Tunnel engineering Ministry of EducationSouthwest Jiaotong UniversityChengdu 610031China key laboratory of engineering structures of heavy haul railway Ministry of EducationCentral South UniversityChangsha 410075China State key laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China

During deep buried hard-brittle rock tunnel excavation,the surrounding rock experiences a complicated stress path and stress adjustment *** the adjusted stress exceeds the ultimate bearing capacity of rockmass,a rock failure mode defined as stress-cracking type will *** order to investigate the effect of stress paths on failure mechanism and progressive damage of deep-buried rockmass,the cyclic loading-unloading,loading-unloading,uniaxial,conventional and unloading triaxial compression tests on samples of hard-brittle sandstone were *** to the experimental results,increase in the confining pressure was beneficial to improve the mechanical parameters of rock,but it will reduce the brittle failure *** with conventional triaxial compression,the sandstone under unloading state had more remarkable stress drop and unstable failure ***,it was found that the energy dissipation and energy release in the whole process of rock deformation were the internal power of driven rock progressive *** the increase of confining pressure,the energy hardening and energy accumulation features of rock were weakened,while the progressive damage evolution characteristics could be *** unloading state,more energy could be converted into elastic energy in the energy softening phase(σeb-σP),so that the prepeak damage rate of rock was lower than that of conventional triaxial compression ***,the energy dissipation rate of rock after peak strength decreased linearly with the increase of confining pressure under conventional triaxial compression state,while in unloading state it showed the opposite law.

关键词： Hard-brittle rock Stress path Confining pressure Failure mechanism Progressive damage

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

Seismic dynamic stability of double-slider rock slopes containing tension cracks

引用

Journal of Mountain Science 2023年第7期20卷 2093-2106页

作者： ZHU Chen-hao ZHAO Lian-heng HU Shi-hong ZUO Shi YU Cheng-hao School of Civil engineering Central South UniversityChangsha 410075China key laboratory of heavy-haul railway engineering Structure Ministry of EducationCentral South UniversityChangsha 410075China

Earthquakes have significant impact on rock slopes,thus studying the seismic stability of double-slider rock slopes containing tension cracks is *** proposed an analysis method on the seismic dynamic slope *** method utilizes discrete Fourier transform to decompose real earthquake waves into a combination of harmonic *** waves are then used in conjunction with the pseudo-dynamic method and safety factor calculation formula to compute the safety *** approach accurately captures the influence of seismic time history characteristics on the dynamic stability of double-slider rock slopes containing tension *** minimum safety factor in the obtained time history curves of the safety factor reflects the most unfavorable state of the slopes under seismic *** analysis is conducted using six sets of actual earthquake ground motion data obtained from the Pacific Earthquake engineering Research Center’s NGAWest2 ground-shaking record *** conclusions are as follows:(1)There is an inverse correlation between the average seismic acceleration amplitude and the minimum safety ***,the seismic acceleration amplitude standard deviation shows a positive correlation with the minimum safety *** global sensitivity of geometric parameters in the slope model is higher than other influencing factors.(2)The proposed dynamic stability analysis method can capture the dynamic characteristics of earthquakes,emphasizing the minimum safety factor of the slope in the seismic time history as a stability *** contrast,the pseudo-static method may yield unsafe results.(3)A safety factor expression considering hydrostatic pressure is proposed.A negative correlation was observed between the height of the water level line and the minimum safety factor.

关键词： Earthquake Rock slope Tension crack Modified Pseudo-Dynamic Method Discrete Fourier transform

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

Influence of non-dimensional strength parameters on the seismic stability of cracked slopes

引用

Journal of Mountain Science 2019年第1期16卷 153-167页

作者： ZHAO Lian-heng CHENG Xiao LI De-jian ZHANG Ying-bin School of Civil engineering Central South University key laboratory of heavy-haul railway engineering Structure Ministry of Education Central South University key laboratory of Transportation Tunnel engineering Ministry of Education Southwest Jiaotong University Department of Geotechnical engineering School of Civil Engineering Southwest Jiaotong University

Cracks in rock or soil slopes influence the stability and durability of the slopes. Seismic forces can trigger slope disasters, particularly in the cracked slopes. Considering the nonlinear characteristics of materials, the more generalized nonlinear failure criterion proposed by Baker is adopted. The influence of non-dimensional strength parameters on the stability of cracked slopes under earthquakes is performed using the upper bound limit analysis. The seismic displacement is calculated by adopting the logarithmic spiral failure surface according to the sliding rigid block model. Based on the existing studies, two methods for the stability analysis of cracked slopes under earthquakes are introduced: the pseudo-static method(with the factor of safety(Fs) as an evaluation index), and the displacement-based method(with the seismic displacement as an evaluation index). The pseudo-static method can only determine the instantaneous stability state of the cracked slope, yet the displacement-based methodreflects the stability variation of cracked slopes during earthquakes. The results indicate that the nondimensional strength parameters affect the factor of safety and seismic displacement of slopes significantly. The non-dimensional strength parameter(n) controlling the curvature of strength function shapes on the slope stability is affected by other parameters. Owing to cracks, the effect of non-dimensional strength parameters on seismic displacement becomes more significant.

关键词： Cracked slopes Upper bound limit analysis(UBLA) Generalized nonlinear failure criterion Pseudo-static method Displacement-based method

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

Assessing the range of blasting-induced cracks in the surrounding rock of deeply buried tunnels based on the unified strength theory

引用

Journal of Central South University 2024年第7期31卷 2341-2364页

作者： LI Liang CHEN Jia-jun ZHAO Lian-heng HE Ke-pei HU Shi-hong LI Hua-long School of Civil engineering Central South UniversityChangsha 410075China key laboratory of heavy-haul railway engineering Structure Ministry of EducationCentral South UniversityChangsha 410075China Hunan Provincial key laboratory for Disaster Prevention and Mitigation of Rail Transit engineering Structure Central South UniversityChangsha 410075China

Blasting-induced cracks in the rock surrounding deeply buried tunnels can result in water gushing and rock mass collapse,posing significant safety ***,previous theoretical studies on the range of blasting-induced cracks often ignore the impact of the in-situ stress,especially that of the intermediate principal *** particle displacement−crack radius relationship was established in this paper by utilizing the blasthole cavity expansion equation,and theoretical analytical formulas of the stress−displacement relationship and the crack radius were derived with unified strength theory to accurately assess the range of cracks in deep surrounding rock under a blasting *** analysis showed that the crushing zone size was positively correlated with in-situ stress,intermediate principal stress,and detonation pressure,whereas negatively correlated with Poisson ratio and decoupling *** dilatancy angle-crushing zone size relationship exhibited nonmonotonic *** relationships in the crushing zone and the fracture zone exhibited opposite trends under the influence of only in-situ stress or intermediate principal *** the in-situ stress increased from 0 to 70 MPa,the rate of change in the crack range and the attenuation rate of the peak vibration velocity gradually slowed.

关键词： deep drilling and blasting cracks in surrounding rock unified strength theory intermediate principle stress in-situ stress cavity expansion dilatancy characteristics

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

Modelling the temporal-varied nonlinear velocity profile of debris flow using a stratification aggregation algorithm in 3D-HBP-SPH framework

引用

Journal of Mountain Science 2024年第12期21卷 3945-3960页

作者： HAN Zheng XIE Wendu ZENG Chuicheng LI Yange CHEN Guangqi CHEN Ningsheng HU Guisheng WANG Weidong School of Civil engineering Central South UniversityChangsha 410075China Hunan Provincial key laboratory for Disaster Prevention and Mitigation of Rail Transit engineering structures Changsha 410075China The key laboratory of engineering structures of heavy haul railway Ministry of EducationChangsha 410075China Department of Civil engineering Kyushu UniversityFukuoka 819-0395Japan key Lab of Mountain Hazards and Surface Processes Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China

Estimation of velocity profile within mud depth is a long-standing and essential problem in debris flow *** now,various velocity profiles have been proposed based on the fitting analysis of experimental measurements,but these are often limited by the observation conditions,such as the number of configured ***,the resulting linear velocity profiles usually exhibit limitations in reproducing the temporal-varied and nonlinear behavior during the debris flow *** this study,we present a novel approach to explore the debris flow velocity profile in detail upon our previous 3D-HBPSPH numerical model,i.e.,the three-dimensional Smoothed Particle Hydrodynamic model incorporating the Herschel-Bulkley-Papanastasiou ***,we propose a stratification aggregation algorithm for interpreting the details of SPH particles,which enables the recording of temporal velocities of debris flow at different mud *** analyze the velocity profile,we introduce a logarithmic-based nonlinear model with two key parameters,that a controlling the shape of velocity profile and b concerning its temporal *** verify the proposed velocity profile and explore its sensitivity using 34 sets of velocity data from three individual flume experiments in previous *** results demonstrate that the proposed temporalvaried nonlinear velocity profile outperforms the previous linear profiles.

关键词： Debris flow Velocity profile Temporal varied feature Nonlinear Stratification aggregation algorithm

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

A Novel Vibration-Based Self-Adapting Method to Acquire Real-Time Following Distance for Virtually Coupled Trains

引用

IEEE/CAA Journal of Automatica Sinica 2025年第1期 27-39页

作者： Qinglai Zhang Jianmin Gao Qing Wu Qinglie He Libin Tie Wanming Zhai Shengyang Zhu State key laboratory of Rail Transit Vehicle System Southwest Jiaotong University IEEE Centre for railway engineering Central Queensland University National Energy railway Equipment Co. LTDNational Energy Group

Virtual coupling(VC) is an emerging technology for addressing the shortage of rail transportation capacity. As a crucial enabling technology, the VC-specific acquisition of train information, especially train following distance(TFD), is *** this paper, a novel method is proposed to acquire real-time TFD by analyzing the vibration response of the front and following trains, during which only onboard accelerometers and speedometers are required. In contrast to the traditional arts of train positioning, this method targets a relative position between two adjacent trains in VC operation, rather than the global positions of the trains. For this purpose, an adaptive system containing three strategies is designed to cope with possible adverse factors in train operation. A vehicle dynamics simulation of a heavy-haul railway is implemented for the evaluation of feasibility and performance. Furthermore, a validation is conducted using a set of data measured from in-service Chinese high-speed trains. The results indicate the method achieves satisfactory estimation accuracy using both simulated and actual data. It has favorable adaptability to various uncertainties possibly encountered in train operation. Additionally, the method is preliminarily proven to adapt to different locomotive types and even different rail transportation modes. In general, such a method with good performance, low-cost, and easy implementation is promising to apply.

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

Time-dependent squeezing deformation mechanism of tunnels in layered soft-rock stratum under high geo-stress

引用

Journal of Mountain Science 2021年第5期18卷 1371-1390页

作者： CHEN Zi-quan HE Chuan WANG Jun MA Chun-chi key laboratory of Transportation Tunnel engineering Ministry of EducationSouthwest Jiaotong UniversityChengdu 610031China State key laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China Sichuan Highway Planning Survey Design and Research Institute Ltd Chengdu 610041China key laboratory of engineering structures of heavy haul railway Ministry of EducationCentral South UniversityChangsha 410075China

Large squeezing deformation of layered soft rock tunnel under high geo-stress has a significant time-dependent deformation *** this paper,we studied the deformation mechanism during the construction period of deep-buried softrock tunnel by means of a combination of field observations and a numerical ***,a new classification criterion for large deformations based on the power exponent variation law between the deformation and the strength-stress ratio is ***,the initial damage tensor reflecting the bedding plane(joint)distribution and an equivalent damage evolution equation derived from the viscoplastic strain are introduced based on the geometric research method,i.e.,a new rheological damage model(RDL model)of layered soft rock is established consisting of elastic,viscous,viscoelastic,viscoplastic and plastic elements.A field test was conducted on the Maoxian tunnel in Sichuan province,southwestern China,which is in broken phyllite(layered soft rock)under high *** tunnel has experienced large deformation due to serious squeezing pressure,thus we adopted double primary support method to overcome the supporting structure failure *** rheological parameters of phyllite in the Maoxian tunnel were recognized by using SA-PSO optimization,and the RDL model does a good job in describing the time-dependent deformation behavior of a layered soft-rock tunnel under high ***,the RDL model was used to investigate the supporting effect and bearing mechanism of the double primary support *** with the single primary support method,the surrounding rock pressure,secondary lining force,surrounding rock deformation,and the depth of the damage to the rock mass was reduced by 40%-60%after the double primary support method was used.

关键词： Deformation mechanism Layered soft rock tunnel High geostress Large squeezing deformation Rheological damage model

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

Sensitivity analysis of regional rainfall-induced landslide based on UAV photogrammetry and LSTM neural network

引用

Journal of Mountain Science 2023年第11期20卷 3312-3326页

作者： ZHAO Lian-heng XU Xin LYU Guo-shun HUANG Dong-liang LIU Min CHEN Qi-min School of Civil engineering Central South UniversityChangsha 410075China key laboratory of heavy-haul railway engineering Structure Ministry of EducationCentral South UniversityChangsha410075China Hunan Provincial key laboratory for Disaster Prevention and Mitigation of Rail Transit engineering structures CentralSouth UniversityChangsha 410075China Hunan Tieyuan Civil engineering Testing Co. LTDChangsha 410075China

Rainfall stands out as a critical trigger for landslides,particularly given the intense summer rainfall experienced in Zheduotang,a transitional zone from the southwest edge of Sichuan Basin to Qinghai Tibet *** area is characterized by adverse geological conditions such as rock piles,debris slopes and unstable ***,due to the absence of historical rainfall records and landslide inventories,empirical methods are not applicable for the analysis of rainfall-induced *** we employ a physically based landslide susceptibility analysis model by using highprecision unmanned aerial vehicle(UAV)photogrammetry,field boreholes and long short term memory(LSTM)neural network to obtain regional topography,soil properties,and rainfall *** applied the Transient Rainfall Infiltration and Grid-Based Regional Slope-Stability(TRIGRS)model to simulate the distribution of shallow landslides and variations in porewater pressure across the region under different rainfall intensities and three rainfall patterns(advanced,uniform,and delayed).The landslides caused by advanced rainfall pattern mostly occurred in the first 12 hours,but the landslides caused by delayed rainfall pattern mostly occurred in the last 12 ***,all the three rainfall patterns yielded landslide susceptibility zones categorized as high(1.16%),medium(8.06%),and low(90.78%).Furthermore,total precipitation with a rainfall intensity of 35 mm/h for 1 hour was less than that with a rainfall intensity of 1.775 mm/h for 24hours,but the areas with high and medium susceptibility increased by 3.1%.This study combines UAV photogrammetry and LSTM neural networks to obtain more accurate input data for the TRIGRS model,offering an effective approach for predicting rainfall-induced shallow landslides in regions lacking historical rainfall records and landslide inventories.

关键词： Regional landslide TRIGRS UAV photography Rainfall landslide LSTM neural network

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

Three-dimensional limit variation analysis on the ultimate pullout capacity of the anchor cables based on the Hoek-Brown failure criterion

引用

Journal of Mountain Science 2024年第3期21卷 1036-1047页

作者： ZUO Shi ZHAO Lianheng HU Shihong College of Civil engineering Changsha UniversityChangsha 410022China Hunan Provincial key laboratory for Disaster Prevention and Mitigation of Rail Transit engineering Structure Key Laboratory of Heavy-Haul Railway Engineering StructureMinistry of EducationCentral South UniversityChangsha 410075China College of Civil engineering Central South UniversityChangsha 410075China

Only simplified two-dimensional model and a single failure mode are adopted to calculate the ultimate pullout capacity(UPC)of anchor cables in most previous *** study focuses on a more comprehensive combination failure mode that consists of bond failure of an anchorage body and failure of an anchored rock *** three-dimensional ultimate pullout capacity of the anchor cables is calculated based on the Hoek-Brown failure criterion and variation analysis *** numerical solution for the curvilinear function in fracture plane is obtained based on the finite difference theory,which more accurately reflects the failure state of the anchor cable,as opposed to that being assumed in *** results reveal that relying solely on a single failure mode for UPC calculations has limitations,as changes in parameter values not only directly impact the UPC value but also can alter the failure model and thus the calculation method.

关键词： Anchor cable Ultimate pullout capacity(UPC) Failure model Variation analysis Hoek-Brown failure criterion

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

Upper bound analysis of ultimate pullout capacity of shallow 3-D circular plate anchors based on nonlinear Mohr-Coulomb failure criterion

引用

Journal of Central South University 2018年第9期25卷 2272-2288页

作者： ZHAO Lian-heng TAN Yi-gao HU Shi-hong DENG Dong-ping YANG Xin-ping School of Civil engineering Central South University key laboratory of heavy-haul railway engineering Structure of Ministry of Education Central South University

Based on the nonlinear Mohr-Coulomb failure criterion and the associated flow rules,the three-dimensional(3-D)axisymmetric failure mechanism of shallow horizontal circular plate anchors that are subjected to the ultimate pullout capacity(UPC)is determined.A derivative function of the projection function for projecting the 3-D axisymmetric failure surface on plane is deduced using the variation *** using difference principle,the primitive function of failure surface satisfying boundary condition and numerical solution to its corresponding ultimate pullout capacity function are *** influences of nonlinear Mohr-Coulomb parameters on UPC and failure mechanism are *** result shows that UPC decreases with dimensionless parameter m and uniaxial tensile strength increases but increases when depth and radius of plate anchor,surface overload,initial cohesion,geomaterial density and friction angle *** failure surface is similar to a symmetrical spatial funnel,and its shape is mainly determined by dimensionless parameter m;the surface damage range expands with the increase of radius and depth of the plate anchor as well as initial cohesion but decreases with the increase of dimensionless parameter m and uniaxial tensile strength as well as geomaterial *** the dimensionless parameter m=2.0,the numerical solution of UPC based on the difference principle is proved to be feasible and effective through the comparison with the exact *** addition,the comparison between solutions of UPC computed by variation method and those computed by upper bound method indicate that variation method outperforms upper bound method.

关键词： shallow circular plate anchors ultimate pullout capacity variation analysis nonlinear Mohr-Coulomb failure criterion upper bound limit analysis

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

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：