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Cohesive Strength and Seismogenic Stress Pattern along the Active Basement Faults of the Precordillera-Sierras Pampeanas Ranges,Western Argentina:An Experimental Analysis by Means of Numerical Model
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作者 Md. Rafiqul Islam 《Journal of Mountain Science》 SCIE CSCD 2009年第4期331-345,共15页
A two-dimensional finite element method (FEM) model that incorporates faults, elastic rock physical properties, topographical load due to gravity and far-field plate velocity boundary conditions was used to recogniz... A two-dimensional finite element method (FEM) model that incorporates faults, elastic rock physical properties, topographical load due to gravity and far-field plate velocity boundary conditions was used to recognize the seismogenic stress state along the fold-and-thrust belt of the Precordillera-Sierras Pampeanas ranges of western Argentina. A plane strain model with nine experiments was presented here to examine the fault strength with two major rock phyical properties: cohesion and angle of internal friction. Mohr-Coulomb failure criterion with bulk rock properties were applied to analyse faults. The stress field at any point of the model was assumed to be comprised of gravitational and tectonic components. The analysis was focused to recognize the seismogenic shear strain concentrated in the internal-cristaline domain of the orogene shown by the modeling. Modeling results are presented in terms of four parameters, i. e., (i) distributions, orientations, and magnitudes of principal stresses (σ1 and σ3), (ii) displacement vector1 (iii) strain distribution, and (iv) maximum shear stress (τmax) contour line within the model. The simulation results show that the compressive stress is distributed in and around the fault systems. The overall orientation of of σ1 is in horizontal directions, although reorientations do occur within some stress weaker parts, especially subsequent to the faults. A large-scale shear stress is accumulating along the active faults of Tapias-Villicum Fault (TVF), Salinas-Berros Fault (SBF), Ampacama-Niquizanga Fault (ANF) and Las Charas Fault (CF), which could act as local stress and strain modulators to localize the earthquakesoccurrence. 展开更多
关键词 Finite element method Rock physical property Fold-and-thrust belt fault strength Seismogenic shear stress pattern
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Risk assessment of fault reactivation considering the heterogeneity of friction strength in the BZ34-2 Oilfield,Huanghekou Sag,Bohai Bay Basin,China 被引量:3
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作者 Ye-Jun Jin Ling-Dong Meng +4 位作者 Ding-You Lyu Xiao-Fei Fu Jiang-Bo Huang Si-Jia Cao Jian-Da Li 《Petroleum Science》 SCIE EI CSCD 2023年第5期2695-2708,共14页
The hazards of fault reactivation caused by fluid injection are a growing concern.However,traditional evaluation methods of fault stability are likely to underestimate the risk in fault segments with a high clay conte... The hazards of fault reactivation caused by fluid injection are a growing concern.However,traditional evaluation methods of fault stability are likely to underestimate the risk in fault segments with a high clay content.Therefore,an extended evaluation method of fault stability(ECPP)incorporating the heterogeneity in friction strength caused by variation in the clay content within the fault zone is established in this study.After characterizing the current stress field of the BZ34-2 Oilfield in the Huanghekou Sag,Bohai Bay Basin,the reactivation potential of faults is evaluated using both traditional and ECPP methods.Traditional evaluation of fault stability shows that all faults are stable in the present stress field.Faults oriented ENE have a relatively high risk.The maximum sustainable fluid pressure Δp is approximately 8.8-8.9 MPa and 9.3-9.9 MPa.When considering the heterogeneity in fault friction strength,the fault stability is clearly controlled by the clay content of the faults.The high-risk fault segments assessed using traditional methods are no longer obvious,which reflects the importance of incorporating friction strength heterogeneity in the process of fault evaluation.Moreover,the results also show that most fault segments are activated when the fault zone is dominated by montmorillonite,reflecting the strong influence of clay mineral types on fault stability.The factors influencing the heterogeneity of fault friction strength are very complicated in actual situations.Therefore,future work should focus on establishing a database through a large number of experiments and investigating the relationship between the friction coefficient and the main controlling factors. 展开更多
关键词 faultreactivation In-situ stress strength heterogeneity of fault friction Huanghekou Sag
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First-principles study of the effects of selected interstitial atoms on the generalized stacking fault energies, strength, and ductility of Ni 被引量:1
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作者 李春霞 党随虎 +2 位作者 王丽萍 张彩丽 韩培德 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第11期454-458,共5页
We analyze the influences of interstitial atoms on the generalized stacking fault energy (GSFE), strength, and ductility of Ni by first-principles calculations. Surface energies and GSFE curves are calculated for t... We analyze the influences of interstitial atoms on the generalized stacking fault energy (GSFE), strength, and ductility of Ni by first-principles calculations. Surface energies and GSFE curves are calculated for the (112) (111) and / 101) ( 1 1 1) systems. Because of the anisotropy of the single crystal, the addition of interstitials tends to promote the strength of Ni by slipping along the (10T) direction while facilitating plastic deformation by slipping along the (115) direction. There is a different impact on the mechanical behavior of Ni when the interstitials are located in the slip plane. The evaluation of the Rice criterion reveals that the addition of the interstitials H and O increases the brittleness in Ni and promotes the probability of cleavage fracture, while the addition of S and N tends to increase the ductility. Besides, P, H, and S have a negligible effect on the deformation tendency in Ni, while the tendency of partial dislocation is more prominent with the addition of N and O. The addition of interstitial atoms tends to increase the high-energy barrier γmax, thereby the second partial resulting from the dislocation tends to reside and move on to the next layer. 展开更多
关键词 first principles generalized stacking fault energy Nickel based alloys strength and ductility
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A two-dimensional earthquake fault modeling with fractal structure strength distribution
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作者 陈祥熊 《Acta Seismologica Sinica(English Edition)》 CSCD 1996年第4期59-69,共11页
In this paper a two dimensional (2 D) model of earthquake fault rupturing was presented. It was estabilished on the basis of 1 D spring block model. Using this model, we studied the dynamical plane strain fractur... In this paper a two dimensional (2 D) model of earthquake fault rupturing was presented. It was estabilished on the basis of 1 D spring block model. Using this model, we studied the dynamical plane strain fracture problem, modeled the whole dynamical process of nucleating, expanding and propagating of fracture on a 2 D fault with homogeneous or inhomogeneous rupture strength distribution. Our studies show that under homogeneous prestress condition, the fault will gain enough momentum to tear strong obstacles in their propagating path. The rupturing fronts can also propagate forth around the isolated barriers. It is shown that the stopping conditions for rupturing processes play an important role in modeling whole earthquake process. We also studied the dynamical rupturing problems of the fault on which the rupture strength distribution is inhomogeneous, and modeled the earthquake sequence generated on a 2 D fault with the strength distribution of fractal structure. It possesses some similar features as a seismic sequence in the nature. These features mainly depend on the distribution of rupture strength on the fault plane and the level of initial stress drop. The modeling studies which were established on the basis of experiments and observations provided the physical basis for explaining some statistical rules of seismicity. 展开更多
关键词 earthquake fault fracture strength fractal dynamical rupture process.
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Strength reduction factors for seismic analyses of buildings exposed to near-fault ground motions 被引量:2
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作者 Qu Honglue Zhang Jianjing J.X. Zhao 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2011年第2期195-209,共15页
To estimate the near-fault inelastic response spectra, the accuracy of six existing strength reduction factors (R) proposed by different investigators were evaluated by using a suite of near-fault earthquake records... To estimate the near-fault inelastic response spectra, the accuracy of six existing strength reduction factors (R) proposed by different investigators were evaluated by using a suite of near-fault earthquake records with directivity-induced pulses. In the evaluation, the force-deformation relationship is modelled by elastic-perfectly plastic, bilinear and stiffness degrading models, and two site conditions, rock and soil, are considered. The R-value ratio (ratio of the R value obtained from the existing R-expressions (or the R-p-T relationships) to that from inelastic analyses) is used as a measurement parameter. Results show that the R-expressions proposed by Ordaz & Perez-Rocha are the most suitable for near-fault ground motions, followed by the Newmark & Hall and the Berrill et al. relationships. Based on an analysis using the near-fault ground motion dataset, new expressions of R that consider the effects of site conditions are presented and verified. 展开更多
关键词 strength reduction factors near-fault ground motion response spectra force-deformation relationship
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Effect of mineralogy on friction-dilation relationships for simulated faults:Implications for permeability evolution in caprock faults 被引量:1
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作者 Fengshou Zhang Mengke An +2 位作者 Lianyang Zhang Yi Fang Derek Elsworth 《Geoscience Frontiers》 SCIE CAS CSCD 2020年第2期439-450,共12页
This paper experimentally explores the frictional sliding behavior of two simulated gouges:one,a series of quartz–smectite mixtures,and the other,powdered natural rocks,aiming to evaluate and codify the effect of min... This paper experimentally explores the frictional sliding behavior of two simulated gouges:one,a series of quartz–smectite mixtures,and the other,powdered natural rocks,aiming to evaluate and codify the effect of mineralogy on gouge dilation and frictional strength,stability,and healing.Specifically,velocity-stepping and slide-hold-slide experiments were performed in a double direct shear configuration to analyze frictional constitutive parameters at room temperature,under normal stresses of 10,20,and 40 MPa.Gouge dilation was measured based on the applied step-wise changes in shear velocity.The frictional response of the quartz–smectite mixtures and powdered natural rocks are affected by their phyllosilicate content.Frictional strength and healing rates decrease with increasing phyllosilicate content,and at 20 wt.%a transition from velocity-weakening to velocity-strengthening behavior was noted.For both suites of gouges,dilation is positively correlated with frictional strength and healing rates,and negatively correlated with frictional stability.Changes in the permeability of gouge-filled faults were estimated from changes in mean porosity,indexed through measured magnitudes of gouge dilation.This combined analysis implies that the reactivation of caprock faults filled with phyllosilicaterich gouges may have a strong influence on permeability evolution in caprock faults. 展开更多
关键词 fault gouge MINERALOGY strength and stability Frictional healing Gouge dilation Permeability
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Pseudotachylyte-Induced Weakness of Plate-Boundary Fault:Insight from the Indus-Tsangpo Suture between India and Asia
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作者 XU Zhiqin JI Shaocheng ZHOU Xin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2019年第1期1-11,共11页
Although the Indus-Tsangpo Suture(ITS) is the most spectacular thrust system of continent-continent collision in the world, fundamental questions about its strength evolution and deformation behavior transition remain... Although the Indus-Tsangpo Suture(ITS) is the most spectacular thrust system of continent-continent collision in the world, fundamental questions about its strength evolution and deformation behavior transition remain unanswered. Here we reported, for the first time, frictional melting-induced pseudotachylytes in the intensively deformed felsic rocks along the ITS zone in southern Tibet. This study reveals that pseudotachylytes induced profound weakness of the boundary fault between Indian and Asian plates. The intrinsically low strength of the foliated microlites crystallized from frictional melt or glass(i.e., pseudotachylyte) at seismogenic depths compared with the surrounding coarse-grained quartzofeldspathic rocks in the brittle and semi-brittle regime is sufficient to explain the localization of shear strain, the development of ductile shear zones embedded in strong wall rocks, and the transition from the strong to weak fault behaviors without invoking the presence of high fluid pressure or low friction coefficient metasomatic materials(e.g., smectite or lizardite) within the faults. 展开更多
关键词 PSEUDOTACHYLYTE MYLONITE fault strength strain localization Indus-Tsangpo SUTURE TIBET
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A new early-warning prediction system for monitoring shear force of fault plane in the active fault 被引量:2
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作者 Manchao He Yu Wang Zhigang Tao 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE 2010年第3期223-231,共9页
The most common method used to describe earthquake activity is based on the changes in physical parameters of the earth's surface such as displacement of active fault and seismic wave.However,such approach is not suc... The most common method used to describe earthquake activity is based on the changes in physical parameters of the earth's surface such as displacement of active fault and seismic wave.However,such approach is not successful in forecasting the movement behaviors of faults.In the present study,a new mechanical model of fault activity,considering the shear strength on the fault plane and the influence of the resistance force,is established based on the occurrence condition of earthquake.A remote real-time monitoring system is correspondingly developed to obtain the changes in mechanical components within fault.Taking into consideration the local geological conditions and the history of fault activity in Zhangjiakou of China,an active fault exposed in the region of Zhangjiakou is selected to be directly monitored by the real-time monitoring technique.A thorough investigation on local fault structures results in the selection of two suitable sites for monitoring potential active tectonic movements of Zhangjiakou fault.Two monitoring curves of shear strength,recorded during a monitoring period of 6 months,turn out to be steady,which indicates that the potential seismic activities hardly occur in the adjacent region in the near future.This monitoring technique can be used for early-warning prediction of the movement of active fault,and can help to further gain an insight into the interaction between fault activity and relevant mechanisms. 展开更多
关键词 active faults monitoring EARTHQUAKE early-warning system shear strength
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Research and application of hierarchical model for multiple fault diagnosis
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作者 An Ruoming Jiang Xingwei Song Zhengji 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第4期957-961,共5页
Computational complexity of complex system multiple fault diagnosis is a puzzle at all times. Based on the well known Mozetic's approach, a novel hierarchical model-based diagnosis methodology is put forward for impr... Computational complexity of complex system multiple fault diagnosis is a puzzle at all times. Based on the well known Mozetic's approach, a novel hierarchical model-based diagnosis methodology is put forward for improving efficency of multi-fault recognition and localization. Structural abstraction and weighted fault propagation graphs are combined to build diagnosis model. The graphs have weighted arcs with fault propagation probabilities and propagation strength. For solving the problem of coupled faults, two diagnosis strategies are used: one is the Lagrangian relaxation and the primal heuristic algorithms; another is the method of propagation strength. Finally, an applied example shows the applicability of the approach and experimental results are given to show the superiority of the presented technique. 展开更多
关键词 hierarchical model fault propagation graphs multiple fault diagnosis propagation strength.
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基于密度划分的分布式数据容错存储算法研究 被引量:2
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作者 翁锦阳 朱铁兵 柏志安 《吉林大学学报(信息科学版)》 CAS 2024年第1期67-73,共7页
为保证数据安全性,缓解数据存储空间,提出基于密度划分的分布式数据容错存储算法。过滤分布式数据高密度数据区域,将具有高度相似的目标划分到不同区域,通过数据来源样本点描述数据的密度分布,设定数据弹性,利用概率以及数据粒度推算出... 为保证数据安全性,缓解数据存储空间,提出基于密度划分的分布式数据容错存储算法。过滤分布式数据高密度数据区域,将具有高度相似的目标划分到不同区域,通过数据来源样本点描述数据的密度分布,设定数据弹性,利用概率以及数据粒度推算出对应的存储梯度和强度指数,并在信息存储中引入数据存储梯度和数据弹性,完成分布式数据容错存储。实验证明,所提算法有较高的容错性,带宽吞吐量平稳,平均路径长度较小,能提高网络数据的安全性。 展开更多
关键词 密度划分 分布式数据 数据容错存储 数据粒度 强度指数
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砂质充填型节理剪切力学行为试验研究
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作者 杨泰华 黄友琦 +3 位作者 刘滨 康永水 耿志 周秀斌 《岩土力学》 EI CAS CSCD 北大核心 2024年第12期3645-3657,共13页
由于长期地质构造运动引起的挤压剪切作用,断层破碎带岩体通常充填有类砂质、类泥质等充填物,对岩体的剪切力学特性产生显著影响,并影响岩体的注浆胶结效果。以我国云南某穿越断层带的公路隧道为例,对从断层带采集的岩石和充填物制作成... 由于长期地质构造运动引起的挤压剪切作用,断层破碎带岩体通常充填有类砂质、类泥质等充填物,对岩体的剪切力学特性产生显著影响,并影响岩体的注浆胶结效果。以我国云南某穿越断层带的公路隧道为例,对从断层带采集的岩石和充填物制作成的岩石节理试件进行一系列直剪试验,在此基础上分析了砂质充填对岩石节理注浆前后剪切特性和剪切强度的影响规律。结果表明:(1)对于非注浆试件和注浆试件,砂质充填都会导致节理峰值抗剪强度降低,前者是砂质弱化了节理岩壁之间的接触,后者是砂质影响了水泥结石的强度以及填充层的厚度;(2)注浆能够明显提高砂质充填型岩石节理的抗剪强度,且节理的充填度越高,加固后抗剪强度对比加固前抗剪强度的提升幅度越大;(3)基于节理粗糙度系数-节理压缩强度强度(joint roughness coefficient-joint compression strength,JRC-JCS)准则建立了砂质充填岩石节理以及砂质充填的注浆岩石节理抗剪强度模型,两个模型的预测值与试验数据的吻合度较高。有助于进一步了解断层泥对裂隙岩体注浆胶结的影响。 展开更多
关键词 断层 岩石节理 抗剪强度 砂质充填 注浆
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High temperature strength and ductility of the(C+N)strengthening Fe-Cr-Mn(W,V)steels
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作者 BenfuHu QuanmaoYu +3 位作者 LinLu ChengchangJia HiroshiKinoshita HeishichiroTakahashi 《Journal of University of Science and Technology Beijing》 CSCD 2002年第4期292-297,共6页
Fe-Cr-Mn(W, V) austenite steels used as low radioactive structural materialsin fusion reactor have been investigated. The results show that the high temperature strength andthe creep fracture life of Fe-Cr-Mn(W, V) st... Fe-Cr-Mn(W, V) austenite steels used as low radioactive structural materialsin fusion reactor have been investigated. The results show that the high temperature strength andthe creep fracture life of Fe-Cr-Mn(W, V) steels can be effectively improved through (C+N)complex-strengthening, so can be the high temperature ductility. The strength and ductility of thesteels are superior to that of SUS316 steels and JPCAS below 673 K. The relationship betweenstrength, ductility and the formation temperature is related to the evolution of deformationmicrostructure. The fracture and microstructure observation above 673 K indicates that the main wayto further improve ductility at high temperature is the control of carbide coarsening at the grainboundaries. 展开更多
关键词 Fe-Cr-Mn steels high temperature strength deformation martensite stacking faults (SF)
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基于多水准的高强钢框架-D形偏心支撑结构层剪力分布研究
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作者 李慎 丁世豪 +1 位作者 李晓蕾 穆林 《计算力学学报》 CAS CSCD 北大核心 2024年第4期734-741,共8页
高强钢框架GD形偏心支撑结构中耗能梁段采用Q355钢,非耗能构件(即框架梁和柱)采用高强度钢材,形成一种新型结构体系.耗能梁段在结构遭遇罕遇地震时充分发挥塑性变形耗能,保护高强钢框架处于弹性受力状态,高强钢框架GD形偏心支撑结构由... 高强钢框架GD形偏心支撑结构中耗能梁段采用Q355钢,非耗能构件(即框架梁和柱)采用高强度钢材,形成一种新型结构体系.耗能梁段在结构遭遇罕遇地震时充分发挥塑性变形耗能,保护高强钢框架处于弹性受力状态,高强钢框架GD形偏心支撑结构由于在塑性状态下结构刚度发生改变,其层剪力分布模式不再符合基于强度的设计理论,因此,本文研究了高强钢框架GD形偏心支撑结构在多水准地震动状态下的层剪力分布模式.本文设计了四种不同层数(4层,8层,12层和16层)和三种不同耗能梁段长度(900mm,1000mm和1100mm)的高强钢框架GD形偏心支撑结构,输入40条近场脉冲地震和40条远场地震记录,得到结构在多遇地震、设防地震、罕遇地震以及极罕遇地震下的层剪力分布模式,并对罕遇地震下的层剪力分布模式进行参数标定,获取塑性状态下结构的弹塑性侧向力分布状态. 展开更多
关键词 D形偏心支撑 层剪力分布模式 近场脉冲地震 高强钢框架
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川西须二气藏产水气井合理配产方案探讨
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作者 黄仕林 邓美洲 +2 位作者 毕有益 詹泽东 冯英 《断块油气田》 CAS CSCD 北大核心 2024年第4期661-668,共8页
川西须二气藏储层致密,气井普遍产水,且断缝体规模和水体强度差异大,渗流机理复杂,使得单一产能模型和配产方法适用性差。综合因素导致气井合理配产方案不明确,从而制约了气藏的规模生产和效益开发。文中建立了考虑启动压力梯度、应力... 川西须二气藏储层致密,气井普遍产水,且断缝体规模和水体强度差异大,渗流机理复杂,使得单一产能模型和配产方法适用性差。综合因素导致气井合理配产方案不明确,从而制约了气藏的规模生产和效益开发。文中建立了考虑启动压力梯度、应力敏感等影响的气井气水两相产能评价模型,结合采气指示曲线法、动态分析法、无阻流量法及数学统计法,分别探讨了不同断缝体规模、不同水体强度及综合考虑2种因素影响的气井合理配产方案,须二气藏开发实践证实了其有效性和可靠性。此外,气井配产量与断缝体规模和水体强度的相关性明显,整体表现为裂缝越发育,配产量越高,配产比越低;水体强度越高,配产量越低,配产比也越小。该研究对川西须二气藏气井的合理工作制度制定与气井稳定生产具有较大的实际价值。 展开更多
关键词 断缝体规模 水体强度 产能 合理配产 川西须二气藏
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国外新能源脱网事故对中国电网安全稳定运行的启示 被引量:2
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作者 徐式蕴 王一鸣 +2 位作者 孙华东 毕经天 兰天楷 《电力系统自动化》 EI CSCD 北大核心 2024年第13期1-8,共8页
2016至2023年间,美国、英国和澳大利亚发生了11起新能源大规模脱网事故,严重威胁电网安全稳定运行。文中介绍了这些事故的基本情况,总结分析了事故失稳过程和机理特征,并指出系统强度不足、新能源控制策略不合理、非预想故障防控手段不... 2016至2023年间,美国、英国和澳大利亚发生了11起新能源大规模脱网事故,严重威胁电网安全稳定运行。文中介绍了这些事故的基本情况,总结分析了事故失稳过程和机理特征,并指出系统强度不足、新能源控制策略不合理、非预想故障防控手段不足是事故产生的主要原因。最后,结合中国电网实际,提出了保障新型电力系统安全稳定运行的建议。 展开更多
关键词 电力系统安全稳定 新能源脱网 系统强度 故障穿越策略 新能源控制保护
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不同含水率断层宏微观破裂与强度折减损伤
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作者 高涛 陈云娟 +4 位作者 敬艺 刘建民 王津津 杨传成 宋润钊 《科学技术与工程》 北大核心 2024年第9期3773-3780,共8页
为探究深部地区断层花岗岩不同含水率的宏观与微观跨尺度性质,开展了轴压力学试验、扫描电镜(scanning electron microscope,SEM)试验和X射线衍射(X-ray diffraction,XRD)试验,分析其多尺度破裂与强度折减损伤关系。结果表明:无水状态... 为探究深部地区断层花岗岩不同含水率的宏观与微观跨尺度性质,开展了轴压力学试验、扫描电镜(scanning electron microscope,SEM)试验和X射线衍射(X-ray diffraction,XRD)试验,分析其多尺度破裂与强度折减损伤关系。结果表明:无水状态下宏观以剪切破坏为主且破裂面平滑,而随着含水率提高,其破裂模式以张拉破坏为主,裂纹路径与主应力方向平行且整体松散;低含水率工况微观破裂为沿晶破裂,高含水率工况为沿晶破裂和穿晶破裂的复合型破坏;吸水中期峰值强度与弹性模量两指标衰减率为前期6倍,达到衰减幅度最大限并呈非线性指数下降,吸水后期两指标衰减率回弹至前期状态;劣化系数随含水率增长而降低,吸水前期水分子起润滑岩石内部矿物作用,中后期阶段水分子发生侵蚀软化导致强度大幅度折减。 展开更多
关键词 深部断层 花岗岩 破裂模式 微观机制 强度折减
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煤矿巷道断层滑移型冲击地压试验系统研制与试验验证
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作者 康红普 高富强 +9 位作者 王晓卿 柏建彪 王琦 章冲 王襄禹 杨磊 娄金福 李延辉 王学宁 原贵阳 《煤炭学报》 EI CAS CSCD 北大核心 2024年第9期3701-3710,共10页
断层滑移型冲击地压是煤矿冲击地压的主要类型,目前对其发生全过程缺乏系统研究,其机理与防控仍是根本难题。为实现断层滑移型冲击地压的试验模拟,研制了煤矿巷道断层滑移型冲击地压试验系统,开发了低强高脆相似模拟材料,制备了包含断... 断层滑移型冲击地压是煤矿冲击地压的主要类型,目前对其发生全过程缺乏系统研究,其机理与防控仍是根本难题。为实现断层滑移型冲击地压的试验模拟,研制了煤矿巷道断层滑移型冲击地压试验系统,开发了低强高脆相似模拟材料,制备了包含断层与巷道的大尺寸相似模型,开展了一系列验证试验,实现了巷道冲击破坏模拟与断层剪切滑移模拟。煤矿巷道断层滑移型冲击地压试验系统具备三向六面加载功能,竖向加载能力为20 MPa,模型尺寸为1.50 m×0.75 m×0.75 m;主体框架创新采用键板连接,确保了主体框架的高刚度;发明了蜂窝加载壳结构,实现了密集油缸群加载,能够满足断层滑移型冲击地压试验模拟的要求。开发了适用于断层滑移型冲击地压模拟的相似材料,材料以水玻璃为胶结物、以氟硅酸钠为固化剂、以滑石粉为骨料,单轴抗压强度介于3.44~7.81 MPa,冲击能指数为9.2,弹性能指数为8.83,兼具低强高脆特性。基于试验系统和低强高脆材料实现了静载巷道冲击破坏模拟,验证了低强高脆相似材料模拟巷道冲击破坏的可行性,获得了巷道极限平衡状态的加载条件,巷道帮部连续片落为巷道冲击破坏的显著前兆特征。实现了粗糙锯齿断层的剪切滑移模拟,证实粗糙断层剪切滑移会对巷道形成动载扰动,获得了断层剪切滑移的合理加载方式,采用动区顶部先加载、底部后卸载的方式能够实现断层的瞬间滑移,并能消除对静区应力状态的影响。 展开更多
关键词 断层滑移型冲击地压 试验系统 低强高脆相似材料 物理模拟 巷道冲击破坏
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自动扶梯提升梯级运行安全的方案分析
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作者 梁海健 《科技创新与应用》 2024年第35期167-170,共4页
自动扶梯作为垂直方向上乘客的运输工具,是安全度要求很高的特种设备,梯级作为乘客站立和移动的主要部位,其运行稳定性和安全性直接关系到乘客的安全。梯级故障发生的原因具备多样性,结合规范要求及研究分析自动扶梯运行过程中的梯级损... 自动扶梯作为垂直方向上乘客的运输工具,是安全度要求很高的特种设备,梯级作为乘客站立和移动的主要部位,其运行稳定性和安全性直接关系到乘客的安全。梯级故障发生的原因具备多样性,结合规范要求及研究分析自动扶梯运行过程中的梯级损坏故障及梯级安全事件,针对不同场景下的故障机理,从梯级自身技术参数指标、梯级配套部件等方面研究相应的技术方案提升自动扶梯梯级运行安全。 展开更多
关键词 自动扶梯 梯级 运行安全 故障机理 结构强度
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基于摩擦电效应的滚动轴承故障检测研究
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作者 丁泉文 朱军 《四川轻化工大学学报(自然科学版)》 CAS 2024年第5期31-39,共9页
由金属之间摩擦引起的电荷转移原理提出了一种基于摩擦电信号进行滚动轴承故障检测的方法。为此搭建了滚动轴承摩擦电信号采集实验台,首先设计了不同驱动模式的测试方案,探究摩擦电产生的原因;然后对轴承有/无润滑脂时摩擦电信号与摩擦... 由金属之间摩擦引起的电荷转移原理提出了一种基于摩擦电信号进行滚动轴承故障检测的方法。为此搭建了滚动轴承摩擦电信号采集实验台,首先设计了不同驱动模式的测试方案,探究摩擦电产生的原因;然后对轴承有/无润滑脂时摩擦电信号与摩擦强度的关系进行了探究;最后设计了轴承在不同磨损阶段和不同故障程度下的实验。结果表明,摩擦电信号随轴承的转动而出现,且摩擦电信号受轴承内部摩擦强度影响,摩擦强度越大,产生的电信号也就越大。进一步地将摩擦电信号的近似熵和样本熵作为衡量摩擦电势大小的指标,发现轴承从正常状态至磨损逐渐加剧时,对应指标均随磨损程度增加而增加;另外在内圈故障宽度为0.3、0.6、0.8 mm时,近似熵分别为0.7635、0.9425、1.2212,样本熵分别为0.5416、0.6218、0.9776,呈现出随故障程度加剧而增加的趋势。在此基础上,建立了轴承状态与摩擦电信号之间的对应关系,验证了摩擦电信号在滚动轴承故障检测上的可行性。 展开更多
关键词 摩擦电效应 故障检测 摩擦强度 磨损 故障程度
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断层位置及强度对地下洞室围岩稳定性影响 被引量:29
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作者 黄达 黄润秋 张永兴 《土木建筑与环境工程》 CSCD 北大核心 2009年第2期68-73,共6页
岩体工程的稳定性主要受岩体结构控制,而断层是岩体工程中最常见的一类规模较大的地质不连续面。断层的力学性质及其与洞室的相对位置关系决定了围岩的稳定状态,通过数值计算及三峡工程地下厂房变形监测分析表明:断层的存在严重恶化了... 岩体工程的稳定性主要受岩体结构控制,而断层是岩体工程中最常见的一类规模较大的地质不连续面。断层的力学性质及其与洞室的相对位置关系决定了围岩的稳定状态,通过数值计算及三峡工程地下厂房变形监测分析表明:断层的存在严重恶化了围岩的应力及变形分布,不同断层位置、不同自然应力场条件下围岩的应力及变形特征存在着明显的差异;断层摩擦强度对断层位于顶拱部位时的围岩变形影响较大,而粘聚力对断层位于边墙部位时影响较大,而且这种影响规律随侧压系数的增大而增大。 展开更多
关键词 地下洞室 断层位置 断层强度 变形 应力分布
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