检索结果-内蒙古大学图书馆

Modeling rock slope stability using kinematic, limit equilibrium and finiteelement methods along Mertule Maryam-Mekane Selam road, central Ethiopia (Oct, 10.1007/s40808-022-01563-8, 2022)

引用

MODELING EARTH SYSTEMS AND ENVIRONMENT 2023年第2期9卷 1587-1587页

作者： Bekele, Addisu Meten, Matebie Addis Ababa Sci & Technol Univ Coll Appl Sci Dept Geol POB 16417 Addis Ababa Ethiopia Bule Hora Univ Coll Nat & Computat Sci Dept Geol POB 144 Bule Hora Ethiopia Addis Ababa Sci & Technol Univ Mineral Explorat & Exploitat Ctr Excellence POB 16417 Addis Ababa Ethiopia

Slope failures are among the most common natural geohazards in the world’s hilly and mountainous terrains causing loss of life and damage to infrastructures. The road connecting Mertule Maryam and Mekane Selam towns in central Ethiopia passes through extremely rugged terrain with steep hills and deep valleys/gorges. The purpose of this study is to identify and model the stability of selected rock slope sections along the road. For this, a detailed field investigation, including discontinuity survey, in situ rock testing, rock sampling, measuring slope geometry, and orientation, were carried out. From field observations, eight critical rock slope sections were identified for stability modeling using kinematic, limit equilibrium and finite-element methods. Kinematic modeling, which was performed with dips software, showed wedge and toppling modes of failures at slope sections RSS1 and RSS4, respectively, while planar mode of failure for RSS5 and RSS7. Moreover, limit equilibrium method (LEM) and finite-element method (FEM) models were used to determine the factor of safety (FoS) and the stress reduction factor (SRF), respectively, using Swedge, Rocplane, and Roctopple softwares for wedge, planar, and toppling failures, respectively. These modeling approaches were conducted for static dry, static saturated, dynamic dry, and dynamic saturated conditions. The modeling results at these critical rock slope sections showed that these slopes are stable if FoS/SRF > 1 and unstable if FoS/SRF < 1. The performance of remedial measures at different slope profiles based on LEM modeling showed that reducing the slope angle, slope height, and benching a slope have improved the overall stability of rock slopes. Moreover, this study also recommends the application of shotcrete, rock bolts, anchors, and retaining walls to prevent the failure of the critical rock slope sections along the road.

关键词： Factor of safety finite-element method Kinematic method Limit equilibrium method Slope stability modeling Stress reduction factor

来源：评论

学校读者我要写书评

暂无评论

Forward Modeling Analysis in Advanced Exploration of Cross-Hole Grounded-Wire-Source Transient Electromagnetic method

引用

APPLIED SCIENCES-BASEL 2025年第5期15卷 2672-2672页

作者： Zhu, Jiao Jiang, Zhihai Li, Maofei Dou, Zhonghao Gao, Zhaofeng China Univ Min & Technol Coll Resources & Geosci Xuzhou 221116 Peoples R China

To address the challenge of accurately detecting hidden water inrush hazards ahead of working faces, a cross-hole transient electromagnetic (TEM) method utilizing a grounded-wire source is proposed. The technique positions a step-current-driven grounded-wire source within a working-face borehole, while electrode arrays in adjacent boreholes measure secondary electric field responses. This configuration minimizes interference from metal supports or machines, thereby enhancing the signal-to-noise ratio of the TEM signals. A theoretical analysis based on the unstructured finite-element (FE) method is used to investigate the configuration. The collected data are processed using differential techniques, and the results confirm the method's effectiveness in detecting anomalies. This paper investigates the response of our cross-hole method to anomalies in terms of size, resistivity contrasts, and spatial location, with anomaly boundaries quantitatively delineated via first-order differential analysis. This significantly enhances the capability of TEM detection in identifying anomalies. A comparison between our cross-hole method and the traditional roadway-borehole TEM method, using the trapped column model, demonstrates that the proposed cross-hole device more effectively locates anomalies and improves accuracy. Furthermore, this technique enables the formation of a 3D observation framework by utilizing existing boreholes, presenting promising prospects for future applications.

关键词： cross-hole TEM finite-element method grounded-wire source coal mining

来源：评论

学校读者我要写书评

暂无评论

Application of the Cyclic Strain Accumulation method on Shallow Foundations under Eccentric Cyclic Loading in Sand

引用

INTERNATIONAL JOURNAL OF GEOMECHANICS 2024年第11期24卷

作者： Cao, Shuhan Abdel-Rahman, Khalid Achmus, Martin Leibniz Univ Hannover Inst Geotech Engn D-30167 Hannover Germany

The cyclic loading of foundation structures in sand leads to an accumulation of plastic deformations in the structures. For shallow foundations of high and slender structures such as wind energy converters (WECs), an accumulation of the plastic rotations is expected under cyclic eccentric loading that is imposed by wind loads, which could be crucial for the proof of serviceability. A practical approach to predict the behavior of shallow foundations under high-cycle eccentric loading is under research. In this paper, a numerical approach, the cyclic strain accumulation method (CSAM), which has been validated for cyclically loaded monopiles, is adopted for shallow foundations under eccentric cyclic loading. Modifications to the CSAM are described, which are necessary to apply it to shallow foundations. The results that are gained with the modified method are compared with a medium-scale model test, in which the deformations of a footing with a diameter of 2.0 m under eccentric one-way cyclic loading were investigated. It can be concluded that the CSAM can make realistic predictions and shows satisfying agreement with the measured cyclic behavior. Although more experiments are needed to finally validate the method, the CSAM could be a promising numerical approach to account for the cyclic behavior of shallow foundations under eccentric cyclic loading in sand.

关键词： Cyclic deformation Cyclic strain accumulation method Eccentric loading finite-element method Noncohesive soil Shallow foundation Wind energy converter

来源：评论

学校读者我要写书评

暂无评论

General finite-element Framework of the Virtual Fields method in Nonlinear Elasticity

引用

Journal of Elasticity 2021年第1-2期145卷 265-294页

作者： Mei, Yue Liu, Jiahao Guo, Xu Zimmerman, Brandon Nguyen, Thao D. Avril, Stéphane State Key Laboratory of Structural Analysis for Industrial Equipment Department of Engineering Mechanics Dalian University of Technology Dalian 116023 China International Research Center for Computational Mechanics Dalian University of Technology Dalian 116023 China Ningbo Institute of Dalian University of Technology No.26 Yucai Road Ningbo 315016 Jiangbei District China DUT-BSU Joint Institute Dalian University of Technology Dalian 116023 China Department of Mechanical Engineering Johns Hopkins University Baltimore 21218 MD United States Mines Saint-Étienne Univ Lyon Univ Jean Monnet INSERM U 1059 Sainbiose Saint-Étienne 42023 France

This paper presents a method to derive the virtual fields for identifying constitutive model parameters using the Virtual Fields method (VFM). The VFM is an approach to identify unknown constitutive parameters using deformation fields measured across a given volume of interest. The general principle for solving identification problems with the VFM is first to derive parametric stress field, where the stress components at any point depend on the unknown constitutive parameters, across the volume of interest from the measured deformation fields. Applying the principle of virtual work to the parametric stress fields, one can write scalar equations of the unknown parameters and solve the obtained system of equations to deduce the values of unknown parameters. However, no rules have been proposed to select the virtual fields in identification problems related to nonlinear elasticity and there are multiple strategies possible that can yield different results. In this work, we propose a systematic, robust and automatic approach to reconstruct the systems of scalar equations with the VFM. This approach is well suited to finite-element implementation and can be applied to any problem provided that full-field deformation data are available across a volume of interest. We also successfully demonstrate the feasibility of the novel approach by multiple numerical examples. Potential applications of the proposed approach are numerous in biomedical engineering where imaging techniques are commonly used to observe soft tissues and where alterations of material properties are markers of diseased states. © 2021, The Author(s).

关键词： finite-element method Hyperelasticity Material identification Nonlinear elasticity Soft biological tissues Virtual fields method

来源：评论

学校读者我要写书评

暂无评论

Efficient Jet-Engine Inlet Radar Cross-Section Prediction Using Higher-Order finite-element method and Reduced-Order Modeling

引用

ELECTROMAGNETICS 2014年第3-4期34卷 345-362页

作者： Zdunek, Adam Rachowicz, Waldemar Swedish Def Res Agcy SE-16490 Stockholm Sweden Cracow Univ Technol Krakow Poland

A direct full-wave-based approach and a reduced-order hp-finite-element sub-domain based scattering matrix methodology suitable for calculating the radar cross-section for jet engine air intakes are presented. The convergence of the radar cross-section using uniform mesh refinements and uniform polynomial enrichments are compared. The comparison shows a superiority in favor of the p-enrichments. An efficient method to avoid the bottleneck in the domain decomposition approach at the top level is presented. A very efficient way is to solve the resulting interface problem using the presented reduced-order modeling technique. The radar cross-section can be computed with virtually no loss of accuracy in terms of generalized guided-wave degrees of freedom. The auxiliary generalized scattering matrix approach can also be used without the modal projection or with other generalized inter-facial degrees of freedom to alleviate the interface bottleneck problem.

关键词： finite-element method equation solution cavity domain decomposition scattering matrix air intake wave-guide radar cross-section

来源：评论

学校读者我要写书评

暂无评论

Diakoptic Approach Combining finite-element method and method of Moments in Analysis of Inhomogeneous Anisotropic Dielectric and Magnetic Scatterers

引用

ELECTROMAGNETICS 2014年第3-4期34卷 222-238页

作者： Manic, Ana B. Olcan, Dragan I. Ilic, Milan M. Notaros, Branislav M. Colorado State Univ Dept Elect & Comp Engn Ft Collins CO 80523 USA Univ Belgrade Sch Elect Engn Belgrade Serbia

A new diakoptic method combining the finite-element method and the method of moments is proposed for analysis of inhomogeneous anisotropic dielectric and magnetic scatterers. The method splits the original electromagnetic system into a number of closed-region finite-element method subsystems containing material complexities and an open-region method of moments subsystem, which are analyzed independently. The solution to the original problem is obtained from linear relations between coefficients in expansions of equivalent electric and magnetic surface currents on diakoptic boundary surfaces. Diakoptic electric sources and the magnetic field in finite-element method subsystems are connected using dual sets of higher-order hierarchical basis functions.

关键词： scattering numerical techniques domain decomposition inhomogeneous anisotropic materials diakoptic analysis surface equivalence principle higher-order modeling finite-element method

来源：评论

学校读者我要写书评

暂无评论

Convergence of a Numerical method for Solving the Optimal Control Problem of Panel Forming under Creep Conditions

引用

COMPUTATIONAL MATHEMATICS AND MATHEMATICAL PHYSICS 2024年第1期64卷 45-55页

作者： Bormotin, K. S. Komsomolsk On Amur State Tech Univ Komsomolsk On Amur 681013 Russia

A dynamic programming method is used for the numerical solution of optimal control problems for forming structural elements under creep conditions. The method is implemented in a finite-element software package. The s... 详细信息

关键词： optimal control problems forming process dynamic programming method finite-element method creep

来源：评论

学校读者我要写书评

暂无评论

Permittivity Estimation Based on Transmission Coefficient for Gaussian Beam in Free-Space method

引用

IEICE TRANSACTIONS ON ELECTRONICS 2023年第6期E106C卷 335-343页

作者： Hirayama, Koichi Yanagimoto, Yoshiyuki Sugisaka, Jun-ichiro Yasui, Takashi Kitami Inst Technol Div Informat & Commun Engn Kitami 0908507 Japan EM Labs Inc Kobe 6530842 Japan

In a free-space method using a pair of horn antennas with dielectric lenses, we demonstrated that the permittivity of a sample can be estimated with good accuracy by equalizing a measured transmission coef-ficient of a sample to a transmission coefficient for a Gaussian beam, which is approximately equal to the transmission coefficient for a plane wave mul-tiplied by a term that changes the phase. In this permittivity estimation method, because the spot size at the beam waist in a Gaussian beam needs to be determined, we proposed an estimation method of the spot size by em-ploying the measurement of the Line in Thru-Reflect-Line calibration;thus, no additional measurement is required. The permittivity estimation method was investigated for the E-band (60-90 GHz), and it was demonstrated that the relative permittivity of air with a thickness of 2 mm and a sample with the relative permittivity of 2.05 and a thickness of 1 mm is estimated with errors less than & PLUSMN;0.5% and & PLUSMN;0.2%, respectively. Moreover, in measuring a sample without displacing the receiving horn antenna to avoid the error in measurement, we derived an expression of the permittivity estimation for S parameters measured using a vector network analyzer, and demonstrated that the measurement of a sample without antenna displacement is valid.

关键词： free-space method permittivity estimation Gaussian beam finite-element method

来源：评论

学校读者我要写书评

暂无评论

High-Accuracy Contact Resistance Measurement method for Liquid Metal by Considering Current-Density Distribution in Transfer Length method Measurement

引用

ACS APPLIED MATERIALS & INTERFACES 2023年第37期15卷 44404-44412页

作者： Sato, Takashi Iwase, Eiji Waseda Univ Dept Mat Sci Tokyo 1698555 Japan Waseda Univ Dept Appl Mech & Aerosp Engn Tokyo 1698555 Japan Waseda Univ Kagami Mem Res Inst Mat Sci & Technol Tokyo 1690051 Japan

Liquid metals (LMs) are used as stretchable conductors in various stretchable electronic devices. Moreover, such devices using Ga-based LMs have attracted considerable attention. Herein, we propose a method for accurately determining the contact resistance (R-c) between galinstan and Cu electrodes by considering the current-density distribution in transfer length method (TLM) measurement. Conventional TLM measurements assume that the sheet resistance of the metal electrode (R-she) is negligible compared with that of the object (R-sho), such as Si. However, this assumption may be problematic because the R-sho of Ga-based liquid metals (LMs) is close to the R-she. Therefore, we developed a method of applying current to each measuring electrode and compared it with the conventional method of applying current to the outer electrodes. Simulation results indicated that R-she cannot be ignored for galinstan, and the measured resistance in the contact area (R-c(Total)) included <10% of the R-c component when current was applied to the outer electrodes. In contrast, R-c(Total) included the entire R-c component when current was applied to each electrode. Furthermore, we found that the volume resistances of the object and electrode included in R-c(Total) cannot be ignored. Therefore, for accurate measurement, current must be applied to each electrode, and R-c must be determined from the intersections of the measured and simulated R-c(Total). The obtained contact resistivity (rho(c)), i.e., the contact resistance per unit contact area, was 0.115 m ***(2). The maximum error was 0.085 m ***(2), which was lower than the rho(c) of the solders (>= 10(-1) m ***(2)) with the lowest rho(c) among the electrical interface materials between the electronic components and wiring. This study provides valuable insight into the R-c measurement of LMs, along with new opportunities for the development of stretchable electronics using LMs.

关键词： galinstan contact resistance transfer length method stretchable electronics finite-element method

来源：评论

学校读者我要写书评

暂无评论

Influence of anisotropy on structural dynamic response, from the views of mechanism, analysis method, and implications for pavement design

引用

INTERNATIONAL JOURNAL OF PAVEMENT ENGINEERING 2025年第1期26卷

作者： You, Lingyun Xiao, Zhuang Quan, Weiwen Ma, Xianyong Dong, Zejiao Huazhong Univ Sci & Technol Sch Civil & Hydraul Engn Wuhan Peoples R China Huazhong Univ Sci & Technol Natl Ctr Technol Innovat Digital Construct Wuhan Peoples R China Cent South Univ Forestry & Technol Sch Civil Engn Changsha Peoples R China Harbin Inst Technol Sch Transportat Sci & Engn Harbin Peoples R China

While anisotropic properties of road materials have been extensively investigated, their systematic integration into pavement design frameworks remains incomplete. This study systematically reviews the mechanisms, characteristics and structural implications of material anisotropy in pavement systems through a layered analysis approach (asphalt surface, base and subgrade). The work evaluates three critical dimensions: experimental metrics and characterisation methods for anisotropy quantification, analytical techniques integrating anisotropic behaviour in structural design and anisotropy-induced performance degradation mechanisms. Key findings reveal that compressive modulus predominates as the primary anisotropy indicator in existing studies. Structural consequences include asphalt layer anisotropy exacerbating rutting severity and fatigue deterioration, base layer anisotropy diminishes pavement stress resistance and subgrade anisotropy amplifying permanent deformation. The paper concludes with the following research priorities: mechanistic modelling of anisotropy genesis and its evaluation protocols, field testing innovations for anisotropy assessment and inverse analysis methodologies for parameter identification. This synthesis establishes a foundational framework for advancing anisotropy-aware pavement engineering practices.

关键词： Dynamic analysis Asphalt pavements Analytical methods finite-element method Pavement monitoring

来源：评论

学校读者我要写书评

暂无评论

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

请选择保存的检索档案：

请选择收藏分类：

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

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

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：