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高温加热-液氮冷冲击处理后花岗岩声发射演化特征及损伤本构模型

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岩土工程学报 2024年第9期46卷 1849-1859页

作者：薛熠张智豪刘嘉蔡承政张志镇高峰时旭阳张云西安理工大学西北旱区生态水利国家重点实验室陕西西安710048 中国矿业大学深部岩土力学与地下工程国家重点实验室江苏徐州221116

通过液氮(LN_2)压裂在储层中形成大规模裂隙网络,可以有效提高干热岩储层的热能提取效率。为研究液氮冷冲击作用对不同温度储层的压裂机理和致裂效果的影响,对经过高温加热(25℃~400℃)和液氮冷冲击处理后的花岗岩试样进行单轴压缩试验... 详细信息

通过液氮(LN_2)压裂在储层中形成大规模裂隙网络,可以有效提高干热岩储层的热能提取效率。为研究液氮冷冲击作用对不同温度储层的压裂机理和致裂效果的影响,对经过高温加热(25℃~400℃)和液氮冷冲击处理后的花岗岩试样进行单轴压缩试验,分析了花岗岩力学强度及声发射等多项参数的演化特征,并进一步构建了考虑声发射参数的损伤本构模型,用于评价和预测高温加热-液氮冷冲击处理后花岗岩的变形和强度特征。结果表明:高温和液氮冷冲击的联合作用显著劣化了花岗岩力学性能,峰值强度逐渐降低,最大降幅达到32.8%。同时随着加热温度的升高,不同矿物颗粒之间的热膨胀变形存在差异,导致矿物颗粒之间变形不协调。随着初始加热温度的升高,声发射最大b值平均值显著上升,最大增幅达到32.2%,且声发射振铃计数的初始静默阶段对应的应变量大幅度降低,最大降幅达到54.3%。随着加热温度的升高,液氮冷冲击作用使得微裂纹的生长更为密集,花岗岩在外部荷载作用下,微裂隙不断扩展贯通,更容易形成剪切变形,发生剪切破坏的起始应力水平逐渐下降,最大降幅达到62.3%,同时RA-AF散点值在剪切区域占比增加,最大增幅达到29.5%。此外,本文以声发射振铃累计计数为变量构建了考虑声发射参数的损伤本构模型,能够描述不同高温和液氮冷冲击处理后花岗岩各力学参量在变形破坏过程中的演化特征。

关键词：花岗岩声发射高温加热-液氮冷冲击损伤破坏本构模型

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物流搬运系统供应商发展态势分析

起重运输机械 2024年第12期 88-92页

作者：张之臻田雄北京起重运输机械设计研究院有限公司北京100007

为了深入了解物流搬运系统市场的表现与动向,观察物流搬运系统集成解决方案的发展现状与趋势,文中对物流搬运系统集成的市场情况进行了调研与分析,通过研究发展态势情况,总结未来物流搬运系统市场的发展之道。分析内容中的资料和数据来... 详细信息

为了深入了解物流搬运系统市场的表现与动向,观察物流搬运系统集成解决方案的发展现状与趋势,文中对物流搬运系统集成的市场情况进行了调研与分析,通过研究发展态势情况,总结未来物流搬运系统市场的发展之道。分析内容中的资料和数据来源于对行业公开信息的分析、对业内资深人士和相关企业高管的深度访谈记录,以及综合以上内容作出的客观性性判断和评价,对物流搬运系统的发展提供研究基础,并为其未来发展提供方向指导。

关键词：物流搬运系统系统解决方案发展方向供应

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Experimental investigation on the energy evolution of dry and water-saturated red sandstones

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International Journal of Mining Science and Technology 2015年第3期25卷 383-388页

作者： zhang zhizhen Gao Feng State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and Technology School of Mechanics and Civil Engineering China University of Mining and Technology

In order to investigate the effect of water content on the energy evolution of red sandstone, the axial loading–unloading experiments on dry and water-saturated sandstone samples were conducted, and the distribution and evolution of elastic energy and dissipated energy within the rock were *** results show that the saturation process from dry to fully-saturated states reduces the strength, rigidity and brittleness of the rock by 30.2%, 25.5% and 16.7%, respectively. The water-saturated sample has larger irreversible deformation in the pre-peak stage and smaller stress drop in the post-peak *** saturation process decreases the accumulation energy limit by 38.9%, but increases the dissipated energy and residual elastic energy density, thus greatly reducing the magnitude and rate of energy release. The water-saturated sample has lower conversion efficiency to elastic energy by 3% in the prepeak region; moreover, the elastic energy ratio falls with a smaller range in the post-peak ***, saturation process can greatly reduce the risk of dynamic disaster, and heterogeneous water content can lead to dynamic disaster possibly on the other hand.

关键词： Rock mechanics Energy evolution Energy distribution Triaxial compression Saturation process

“情景应对”视角下应急预案本体构建:以电网企业为例

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安全与环境学报 2024年第7期24卷 2768-2775页

作者：栗婧贠佳颖关城张志珍胡琼中国矿业大学(北京)应急管理与安全工程学院北京100083 国网智能电网研究院有限公司电网数字化技术研究所北京102200 山东潍坊烟草有限公司诸城分公司山东诸城262200

为进一步提升应急预案的可操作性,实现突发事件的快速应对与处置,首先,在“情景应对”视角下,基于公共三角形模型和灾害系统理论思想,结合前因行为后果本体(Antecedent-Behavior-Consequences,ABC)模型和通用形式化本体(General Formal ... 详细信息

为进一步提升应急预案的可操作性,实现突发事件的快速应对与处置,首先,在“情景应对”视角下,基于公共三角形模型和灾害系统理论思想,结合前因行为后果本体(Antecedent-Behavior-Consequences,ABC)模型和通用形式化本体(General Formal Ontology,GFO)顶层模型,构建应急预案“扩展前因行为后果(Extended-Antecedent-Behavior-Consequences,EABC)”顶层本体;其次,根据突发事件应急处置流程与预案文本结构,形成“6W1H”预案结构化范式,并划分情景流、阶段流、决策流、组织流和资源流,表达突发事件发展过程与预案本体要素之间的动态映射关系;最后,以某国网公司台风事件应急预案部分示例,展示基于EABC顶层本体和结构化范式的表达实例。结果显示,构建的本体结构及表达范式能够针对应急处置阶段和过程快速有效实现职责匹配、任务设置和资源调配等功能,为应急预案向数字化和智能化发展提供了思路和方法。

关键词：安全工程情景应对应急预案本体构建结构化

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Research on the energy evolution characteristics and the failure intensity of rocks

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International Journal of Mining Science and Technology 2020年第5期30卷 705-713页

作者： Lin Gao Feng Gao zhizhen zhang Yan Xing School of Mechanics and Civil Engineering China University of Mining and TechnologyXuzhou 221116China State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhou 221116China

It is pretty challenging and difficult to quantitatively evaluate the intensity of dynamic disasters in deep mining *** on the uniaxial loading-unloading experiments for five types of rocks,this paper investigated the energy evolution characteristics,and identified the damage and crack propagation ***,the fragment size distributions of the rocks after failure were *** energy release rate(Ge)and energy dissipation rate(Gd)were then proposed to describe the change of energies per unit volume and per unit *** demonstrated that the more brittle rocks had the shorter stage of unstable crack growth and the lower induced damage at crack damage *** evolution characteristics of the strain energy rates can be easily identified by the crack propagation *** failure intensity index(FId),which equals to the values of Ge/Gd at the failure point,was further put *** can account for the brittleness of the rocks,the intensity of rock failure as well as the degree of rock *** was revealed that a higher FId corresponded to a lower fractal dimension and stronger dynamic failure.

关键词： Energy evolution Crack propagation thresholds Damage Energy release rate Energy dissipation rate Failure intensity

Effect of the layer orientation on mechanics and energy evolution characteristics of shales under uniaxial loading

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International Journal of Mining Science and Technology 2016年第5期26卷 857-862页

作者： Hou Peng Gao Feng Yang Yugui zhang Xiangxiang zhang zhizhen State Key Laboratory for Geomechanics ＆ Deep Underground Engineering China University of Mining ＆ Technology Xuzhou 221116 China School of Mechanics ＆ Civil Engineering China University of Mining ＆ Technology Xuzhou 221116 China

The uniaxial compression tests were conducted on the cylindrical shale specimens with bedding plane inclined at 0° and 90° to the axial loading direction, respectively. Effect of the bedding orientation on the mechanical property and energy evolution characteristics of shales was revealed. The failure mechanisms of the specimens with layers in 0° orientation showed splitting failure along weak bedding, while the specimens with layers in 90° orientation were failed by shearing sliding. The values of compressive strength, elastic modulus and shear modulus of samples at 0° were higher than those of samples at 90°and there was little difference of Poisson's ratio between samples at 0° and 90°. The analysis of the stress–strain energy and acoustic emission(AE) energy indicated that the growth rate of absorbed energy density and elastic energy density at 0° was significantly faster than that at 90°, hence their final values at 0°were relatively larger than the latter. Moreover, higher energy release was observed for specimens at 0°.The energy release and rapid growth of energy dissipation also appeared more early at 0°. The stress ratio63% was a critical point of energy distribution at which differences started to arise between samples at 0°and 90°. These results indicated that the failure of shale at 0° was more violent and devastative than the failure of shale at 90°.

关键词： Shale Layer orientation Energy evolutio Failure mechanism Uniaxial compression AE energy

Visco-elastic-plastic model of deep underground rock affected by temperature and humidity

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Mining Science and Technology 2010年第2期20卷 183-187页

作者： GAO, Yanan GAO, Feng zhang, zhizhen zhang, Tao school of sciences china university of mining & technologyxuzhou 221008china state key laboratory of geomechanics and deep underground engineering china university of mining & technologyxuzhou 2210

As the depth of exploitation increases,studies on constitutive models of rock affected by temperature and humidity become very *** on the Nishihara model,a visco-elastic-plastic rock model was established by using the coefficients of thermal and humidity expansion,thermal viscosity attenuation,humid viscosity attenuation and acceleration rheology *** used the definition of a controlled heat circle to explain the *** results show that the behavior of rock,affected by temperature and humidity,is stable as a function of time when the stress is lower than the first yield stress σS1;the creep rate will increase due to the effect of temperature and humidity when the stress is greater than or equal to σS1;the creep rate will accelerate at an increasing rate when the stress is greater than or equal to the second yield stress σS2,which results in a failure of the *** model derived in this study can completely describe visco-elastic-plastic characteristics and reflects the three stages of rock creep.

关键词： temperature humidity creep controlled heat circle

Thermo-hydro-mechanical coupled mathematical model for controlling the pre-mining coal seam gas extraction with slotted boreholes

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International Journal of Mining Science and Technology 2017年第3期27卷 473-479页

作者： Xue Yi Gao Feng Gao Yanan Liang Xin zhang zhizhen Xing Yan State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining & Technology Xuzhou 221116 China School of Mechanics & Civil Engineering China University of Mining & Technology Xuzhou 221116 China Rock Mass Modeling and Computational Rock Mechanics Laboratories University of Arizona Tucson AZ 85721 USA

Drainage influence radius is the basic parameter for borehole arrangement, while the effect of high pressure water jet slotting technology on borehole drainage influence radius has not been studied systematically. In this paper, a fully thermo-hydro-mechanical(THM) coupled model which represents the non-linear responses of gas extraction was implemented to demonstrate the reliability of this model through history data matching. Based on this model, the susceptibilities of gas extraction with single slotted borehole, including the permeability, the gas pressure, the temperature, the coal adsorption characteristics and the radius of slot, were quantified through a series of simulations. The simulation results revealed that increasing the permeability, initial gas pressure and temperature could develop the influence radius of single slotted borehole. This finite element model and its simulation results can improve the understanding of the coal-gas interactions of underground gas drainage and provide a scientific basis for the optimization of drainage systems.

关键词： Coal seam gasGas extractionThermo-hydro-mechanical modelSlotted boreholes

Experimental investigations on effects of gas pressure on mechanical behaviors and failure characteristic of coals

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第2期15卷 412-428页

作者： Yi Xue P.G.Ranjith Feng Gao zhizhen zhang Songhe Wang State Key Laboratory of Eco-hydraulics in Northwest Arid Region Xi’an University of TechnologyXi’an710048China Deep Earth Energy Laboratory Department of Civil EngineeringMonash UniversityBuilding 60MelbourneVictoria3800Australia State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhou221006China

The mechanical behavior of coal is the key factor affecting underground coal mining and coalbed methane *** this study,triaxial compression and seepage tests were carried out on coal at different gas *** mechanical properties and failure process of coal were studied,as well as the acoustic emission(AE)and strain *** influence of gas pressure on the mechanical parameters of this coal was *** on the conventional energy calculation formula,the pore pressure was introduced through the effective stress formula,and each energy component of coal containing gas was refined *** contribution of gas pressure to the total energy input and dissipation during loading was quantitatively ***,the influence of gas pressure on coal strength was theo-retically analyzed from the perspectives of MohreCoulomb criterion and fracture *** results show that the total absorbed energy comprises the absorbed energy in the axial pressure direction(positive)and in the confining pressure direction(negative),as well as that induced by the pore pressure(initially negative and then positive).The absorbed energy in the axial pressure direction accounts for the main proportion of the total energy absorbed by *** quiet period of AE in the initial stage shortens,and AE activity increases during the pre-peak stage under high gas *** fractal characteristics of AE in three stages are studied using the correlation *** AE process has different forms of self-similarity in various deformation stages.

关键词： Coal Gas pressure Acoustic emission(AE) Strain energy Fractal characteristics