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Progress in Natural Science:Materials International 2005年第12期15卷 1104-1109页

作者： LU Yanli,CHEN Zheng,LI Yongsheng,WANG Yongxin and CHU Zhong State Key Laboratory of Solidification Processing,School of Materials Science and Engineering,Northwestern Polytechnical University,Xi’an 710072,China State Key Laboratory of Solidification Processing School of Materials Science and Engineering Northwestern Polytechnical University Xi'an 710072 China

The early precipitation process of Ni-Al alloy was studied on the atomic scale based on the microscopic phase-field kinetic *** investigated the effect of elastic strain energy on precipitation mechanism and morphological evolution of the *** results show that at the early stage of precipitation,γ’ ordered phase presents non-directional and irregular shape during the process of aging,the γ’ ordered phases change into the quadrate shape and their orientations become more obvious; at the later stage,the γ’ precipitates present quadrate shape with round corner and align along the [100] and [010] *** mechanism of early precipitation for Ni-13at.%A1 alloy is the mixed mechanism of non-classical nucleation growth and spinodal decomposition and near to non-classical nucle-ation growth,and the mechanism of early precipitation for Ni-15.8at.% Al alloy is the mixed mechanism of non-classical nucleation growth and spinodal decomposition and near to spinodal decomposition.

关键词： Ni-Al alloy early precipitation microscopic phase-field simulation elastic strain energy

Effect of elastic strain energy on the core-shell structures of the precipitates in Al-Sc-Er alloys

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Journal of Rare Earths 2012年第12期30卷 1276-1280页

作者：陈思成李长荣连广丽郭翠萍杜振民 School of Materials Science and Engineering University of Science and Technology Beijing

The effect of the elastic strain energy on the core-shell structures was studied in an Al-0.06Sc-0.02Er （at.%） alloy. A theoretical model for the calculation of the elastic strain energy caused by core-shell precipitates, which is applicable to materials with weak elastic anisotropy, was adopted. It was demonstrated that the partitioning of Er to the precipitate core did not reduce the elastic strain energy as expected in the previous study. The resistance due to the elastic strain energy to form an Al3（Sc0.36Ero.64）-Al3（Sc0.8Er0.2） core-shell precipitate was quite small, and could be easily overcome by the decrease of the total interracial energy, which was consistent with the previous experimental results. On the other hand, the resistance due to the elastic strain energy to form an Al3Er-Al3Sc core-shell precipitate was much larger than that to form an Al3（Sc0.36Er0.64）-Al3（Sc0.8Er0.2） core-shell precipitate, thus the partitioning of all the Er atoms to the core was strongly hindered by the elastic strain energy and was not observed in the experiment of the previous study.

关键词： aluminum alloys precipitation core-shell structure elastic strain energy rare earths

Evaluation of rockburst proneness considering specimen shape by storable elastic strain energy

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Deep Underground Science and Engineering 2022年第2期1卷 116-130页

作者： Song Luo Fengqiang Gong School of Resources and Safety Engineering Central South UniversityChangshaChina School of Civil Engineering Southeast UniversityNanjingChina

To systematically assess the rockburst proneness considering specimen shape,multiple groups of laboratory tests were performed on 5 rock materials in cylindrical and cuboid *** linear energy storage(LES)law of both cylindrical and cuboid rock specimens under uniaxial compressive load was confirmed,and the energy storage coefficient was found to be unrelated to specimen *** the basis of LES law,two rockburst proneness indexes,namely the strain energy storage index(W_(et))and the potential energy of elastic strain(PES),were ***,the W_(et),PES,peak-strength strain energy storage index(W_(et))p,and peak-strength potential energy of elastic strain(PESp)were used to assess the rockburst proneness of the cylindrical and cuboid *** addition,the fragment ejection course of specimens under test was recorded by a high-speed ***,the rockburst proneness judgments obtained from the 4 indexes were compared with the qualitative data during rock *** results show that,under similar stress conditions,specimen shape has an ignorable effect on the rockburst proneness as a *** judgment accuracy of the two modified indexes,especially that of the PESp,is favorably improved to evaluate the rockburst proneness of both cylindrical and cuboid ***,misjudgment ofW_(et)^(p)and PESp may still occur in the assessment of rockburst proneness as these two indexes only consider the energy state before rock peak strength and the W_(et)^(p)is formulated in a ratio form.

关键词： cuboid specimen elastic strain energy energy storage rockburst proneness shape effect uniaxial compression

Rockburst mechanism in soft coal seam within deep coal mines

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International Journal of Mining Science and Technology 2017年第3期27卷 551-556页

作者： Zhang Junfei Jiang Fuxing Yang Jianbo Bai Wushuai Zhang Lei School of Civil and Environmental Engineering University of Science & Technology Beijing Beijing 100083 China

A number of rockburst accidents occurring in soft coal seams have shown that the rockburst mechanism involved in soft coal seams is significantly different from that involved in hard coal seams. Therefore, the method used to evaluate rockburst in hard coal seams is not applicable to soft coal seams. This paper established an energy integral model for the rockburst-inducing area and a friction work calculation model for the plastic area. If the remaining energy after the coal seam is broken in the rockburstinducing area is greater than the friction work required for the coal to burst out, then a rockburst accident will occur. Mechanisms of ‘‘quaking without bursting" and ‘‘quaking and bursting" are clarified for soft coal seams and corresponding control measures are proposed as the optimization of roadway layouts and use of ‘‘three strong systems"(strong de-stressing, strong supporting, and strong monitoring).

关键词： Soft coal seam Rockburst Plastic zone elastic strain energy Friction work

A new criterion of rock burst proneness based on residual energy release rate index

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第12期16卷 5004-5026页

作者： Guangbo Chen Jing Zhang Wei Tang Tan Li Guohua Zhang School of Mining and Coal Inner Mongolia University of Science and TechnologyBaotou014010China College of energy and Mining Engineering Shandong University of Science and TechnologyQingdao266590China School of Mining Engineering Heilongjiang University of Science and TechnologyHarbin150022China

The natural property of rock material,whether impact occurs,is the key influencing factor of the occurrence of rock burst *** accurately assess rock burst proneness,this study focuses on typical sandstone as the research *** cyclic loading and unloading tests were conducted to measure the elastic strain energy accumulated in sandstone under different stress levels and a relationship between elastic strain energy and stress level was *** results show that:(1)The peak stress under cyclic loading and unloading conditions is slightly lower than the uniaxial compressive *** an increase in the number of cycles,the internal damage of sandstone continues to accumulate,and the mechanical properties such as compressive strength continue to deteriorate;(2)With an increase in stress,the input strain energy,elastic strain energy,and dissipated strain energy also increase;(3)When the stress is low,the increase in elastic strain energy is large and shows a steady growth;with an increase in stress,the increase of elastic strain energy decreases;(4)The square of stress at any time has a good linear relationship with elastic strain *** to the relationship obtained from the test,the elastic strain energy at the peak stress time can be obtained;(5)A new criterion for assessing rock burst proneness is proposed:residual energy release rate index W_(T),which characterizes the energy release per unit time when the rock burst *** intervals for evaluating the rock burst proneness of the residual energy release rate index W_(T) are as follows:W_(T)2,indicating strong rock burst proneness;and(6)The rationality of the proposed residual energy release rate index W_(T) is verified by the multi-index method and the multi-sample method,and the proposed residual energy release rate index

关键词： energy storage law Rock burst proneness Rock-burst criterion elastic strain energy Residual energy release rate Rationality verification

Study on creep deformation and energy development of underground surrounding rock under four‐dimensional support

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Deep Underground Science and Engineering 2024年第1期3卷 25-38页

作者： Zhanguo Ma Junyu Sun Peng Gong Pengfei Yan Nan Cui Ruichong Zhang School of Mechanics and Civil Engineering China University of Mining and TechnologyXuzhouChina State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering China University of Mining and TechnologyXuzhouChina Department of Mining Engineering Colorado School of MinesGoldenUSA

There is an urgent need to develop optimal solutions for deformation control of deep high‐stress roadways,one of the critical problems in underground *** previously proposed four‐dimensional support(hereinafter 4D support),as a new support technology,can set the roadway surrounding rock under three‐dimensional pressure in the new balanced structure,and prevent instability of surrounding rock in underground ***,the influence of roadway depth and creep deformation on the surrounding rock supported by 4D support is still *** study investigated the influence of roadway depth and creep deformation time on the instability of surrounding rock by analyzing the energy *** elastic strain energy was analyzed using the program redeveloped in *** numerical simulation results indicate that the combined support mode of 4D roof supports and conventional side supports is highly applicable to the stability control of surrounding rock with a roadway depth exceeding 520 *** the increase of roadway depth,4D support can effectively restrain the area and depth of plastic deformation in the surrounding ***,4D support limits the accumulation range and rate of elastic strain energy as the creep deformation time increases.4D support can effectively reduce the plastic deformation of roadway surrounding rock and maintain the stability for a long deformation period of 6 *** confirmed by in situ monitoring results,4D support is more effective for the long‐term stability control of surrounding rock than conventional support.

关键词： coal mines elastic strain energy four‐dimensional support large roadway depth long‐term stability control plastic deformation surrounding rock

Computer simulation of strain-induced morphological transformation of coherent precipitates

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Journal of University of Science and Technology Beijing 2003年第4期10卷 55-60页

作者： Yuhong Zhao, Zheng Chen, and Xiaoling LiDepartment of Materials Science and Engineering, Northwestern Polytechnical University, Xi’an 710072, China Northwestern Polytech Univ Dept Mat Sci & Engn Xian 710072 Peoples R China

The coherent elastic strain-induced morphological transformation of a binarycubic model alloy was simulated with different strain energy parameters. The microscopic diffusionequation was combined with the theory of microscopic elasticity. The results show that when thestrain energy is neglected, the randomly distributed equiaxed particles are obtained with isotropiccharacteristic. It is coarsening that follows the Ostwald ripening mechanism: smaller particlesdwindle and larger particles grow; when the elastic strain is considered, plate precipitates tend toalign along the elastically soft directions with anisotropic characteristic. The particlesgrow in the soft directions and coarsen further; particles dwindle in out of the soft *** the coarsening of the particles localized in the same row or column follows the rule: smallerparticles shrink and larger ones grow.

关键词： elastic strain energy coherent precipitate model alloy and computersimulation

Anchoring properties of substrate with a grating surface

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Chinese Physics B 2007年第2期16卷 493-498页

作者：叶文江邢红玉杨国琛 School of Sciences Hebei University of Technology Tianjin 300130 China

The anchoring properties of substrate with a grating surface are investigated analytically. The alignment of nematic liquid crystal （NLC） in a grating surface originates from two mechanisms, thus the anchoring energy consists of two parts. One originates from the interaction potential between NLC molecules and the molecules on the substrate surface, and the other stems from the increased elastic strain energy. Based on the two mechanisms, the expression of anchoring energy per unit area of a projected plane of this grating surface is deduced and called the equivalent anchoring energy formula. Both the strength and the easy direction of equivalent anchoring energy are a function of the geometrical parameters （amplitude and pitch） of a grating surface. By using this formula, the grating surface can be replaced by its projected plane and its anchoring properties can be described by the equivalent anchoring energy formula.

关键词： anchoring properties anchoring energy elastic strain energy equivalent anchoring energy formula

Discrete element modeling of acoustic emission in rock fracture

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Theoretical & Applied Mechanics Letters 2013年第2期3卷 46-50页

作者： Shunying Ji Shaocheng Di State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology

The acoustic emission （AE） features in rock fracture are simulated numerically with discrete element model （DEM）. The specimen is constructed by using spherical particles bonded via the parallel bond model. As a result of the heterogeneity in rock specimen, the failure criterion of bonded particle is coupled by the shear and tensile strengths, which follow a normal probability distribution. The Kaiser effect is simulated in the fracture process, for a cubic rock specimen under uniaxial compression with a constant rate. The AE number is estimated with breakages of bonded particles using a pair of parameters, in the temporal and spatial scale, respectively. It is found that the AE numbers and the elastic energy release curves coincide. The range for the Kaiser effect from the AE number and the elastic energy release are the same. Furthermore, the frequency-magnitude relation of the AE number shows that the value of B determined with DEM is consistent with the experimental data.

关键词： acoustic emission discrete element model failure criteria elastic strain energy parallelbonding

Nonuniform B-spline Mesh Fairing Method

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Computer Aided Drafting,Design and Manufacturing 1991年第1期2卷 20-28页

作者： RONG Huanzong CHEN Gang ZHANG Weirong

A method for fairing a surface composed of a set of discrete data points distributed in a nonrectangular topological mesh is *** curves are expressed by nonuniform cubic B-spline *** fairing method is minimizing the elastic strain energy of mesh curves and of springs at- tached to the data *** fairing surface can be generated by interpolating through the mesh *** generation and fairing of a ship hull surface is given as an example.

关键词： CAD Ship-hull surface Fairing method elastic strain energy Nonuniform cubic Bspline