According to the distribution of abutment stress in a stope,this research established the mechanical model of mining abutment pressure transmission in floor base on the theory of semi-infnite plate body in elasticity....According to the distribution of abutment stress in a stope,this research established the mechanical model of mining abutment pressure transmission in floor base on the theory of semi-infnite plate body in elasticity.This study takes the 762 working face of Haizi Coal Mine as a case in point,and analyzed the dynamic evolution law of seam floor stress during the mining process.With an organic combination of the mining floor stress and surrounding rock stress,the study obtained the change laws of the maximum principle stress and the minimum one for the floor roadway surrounding rock when mining the upper working face.Considering the non-constant pressure force state and the cracks revolution mechanisms of floor roadway surrounding rock,the research built the mechanical model of roadway stress.Simulation results verify the reliability of the above conclusions.Moreover,this model could provide the theoretical basis and technical support for controlling floor roadway surrounding rock.展开更多
Accuracy of simulated permeability can be improved using soft data during the process of simulation. Integrating soft data with hard data, a method based on COSISIM （sequential indicator cosimulation） was proposed t...Accuracy of simulated permeability can be improved using soft data during the process of simulation. Integrating soft data with hard data, a method based on COSISIM （sequential indicator cosimulation） was proposed to reconstruct permeability. The algorithm COSISIM extends the SISIM （sequential indicator simulation） algorithm to handle secondary data. At the difference of SISIM, data must already be an indicator-coded prior to using COSISIM. The soft data were integrated with hard data using the Markov-Bayes algorithm and must be coded into indicators before they are used. This method was tested on a regional simulation of permeability. The simulated results and the original distribution of permeability were compared. The experimental results demonstrate that this method is practical.展开更多
A study of the characteristics of the accumulative rock failure and its evolution byapplication of the group renormalization method were presented. In addition, the interactionand long-range correlated effects between...A study of the characteristics of the accumulative rock failure and its evolution byapplication of the group renormalization method were presented. In addition, the interactionand long-range correlated effects between the immediate neighboring units was studied.The concept of mechanical transference for model OFC, employed in the study ofself-organized criticality, and the coefficient a were introduced into the calculation model forgroup renormalization. With the introduction, mechanisms for the drastic increase and decrease of failure intensity of rocks were investigated under similar macro-conditions.展开更多
Poor interfacial adhesion and dispersity severely obstruct the continued development of carbon nanotube(CNT)-reinforced epoxy(EP)for potential applications.Herein,hierarchical CNT nanohybrids using nickel phyllosilica...Poor interfacial adhesion and dispersity severely obstruct the continued development of carbon nanotube(CNT)-reinforced epoxy(EP)for potential applications.Herein,hierarchical CNT nanohybrids using nickel phyllosilicate(Ni-PS)as surface decorations(CNT@Ni-PS)were synthesized,and the nanocomposites derived from varied mass fractions of EP and CNT@Ni-PS were prepared.The morphological structures,tribological performances,curing behaviors and thermal properties of EP/CNT@Ni-PS nanocomposites were carefully investigated.Results show that hierarchical CNT nanohybrids with homogeneous dispersion and well-bonded interfacial adhesion in the matrix are successfully obtained,presenting significantly improved thermal and tribological properties.Moreover,analysis on cure kinetics proves the excellent promotion of CNT@Ni-PS on the non-isothermal curing process,lowering the curing energy barrier steadily.展开更多
Fig.7(a,a')on page 1289:It has come to our attention that the SEM picture of Fig.7(a,a')for the worn surface of pure EP are misused,because it has been reported in our previous work and was chosen accidentally...Fig.7(a,a')on page 1289:It has come to our attention that the SEM picture of Fig.7(a,a')for the worn surface of pure EP are misused,because it has been reported in our previous work and was chosen accidentally to denote as the same control sample prepared using the exactly same procedure.The corrected Fig.7(a,a')is shown below.The data analysis,description and conclusion are not affected by this unintentional error.展开更多
基金supported by the National Natural Science Foundation of China(No.51074004)the Open Project of State Key Laboratory Breeding Base for Mining Disaster Prevention and Control of Shandong University of Science and Technology of China(No.MDPC2012KF06)+1 种基金the Natural Science Foundation of Anhui Province of China(No.11040606M102)Young Teachers Science Foundation of Anhui University of Science&Technology of China(No.2012QNZ14)
文摘According to the distribution of abutment stress in a stope,this research established the mechanical model of mining abutment pressure transmission in floor base on the theory of semi-infnite plate body in elasticity.This study takes the 762 working face of Haizi Coal Mine as a case in point,and analyzed the dynamic evolution law of seam floor stress during the mining process.With an organic combination of the mining floor stress and surrounding rock stress,the study obtained the change laws of the maximum principle stress and the minimum one for the floor roadway surrounding rock when mining the upper working face.Considering the non-constant pressure force state and the cracks revolution mechanisms of floor roadway surrounding rock,the research built the mechanical model of roadway stress.Simulation results verify the reliability of the above conclusions.Moreover,this model could provide the theoretical basis and technical support for controlling floor roadway surrounding rock.
基金Supported by the National Natural Science Foundation of China（50874005）
文摘Accuracy of simulated permeability can be improved using soft data during the process of simulation. Integrating soft data with hard data, a method based on COSISIM （sequential indicator cosimulation） was proposed to reconstruct permeability. The algorithm COSISIM extends the SISIM （sequential indicator simulation） algorithm to handle secondary data. At the difference of SISIM, data must already be an indicator-coded prior to using COSISIM. The soft data were integrated with hard data using the Markov-Bayes algorithm and must be coded into indicators before they are used. This method was tested on a regional simulation of permeability. The simulated results and the original distribution of permeability were compared. The experimental results demonstrate that this method is practical.
基金Supported by the National Science Foundation of China (50674002)
文摘A study of the characteristics of the accumulative rock failure and its evolution byapplication of the group renormalization method were presented. In addition, the interactionand long-range correlated effects between the immediate neighboring units was studied.The concept of mechanical transference for model OFC, employed in the study ofself-organized criticality, and the coefficient a were introduced into the calculation model forgroup renormalization. With the introduction, mechanisms for the drastic increase and decrease of failure intensity of rocks were investigated under similar macro-conditions.
基金the National Natural Science Foundation of China(Grant No.51775001)Natural Science Foundation of Anhui Province(Grant No.1908085J20)+1 种基金University Synergy Innovation Program of Anhui Province(Grant No.GXXT-2019-027)the Leading Talents Project in Colleges and Universities of Anhui Province.
文摘Poor interfacial adhesion and dispersity severely obstruct the continued development of carbon nanotube(CNT)-reinforced epoxy(EP)for potential applications.Herein,hierarchical CNT nanohybrids using nickel phyllosilicate(Ni-PS)as surface decorations(CNT@Ni-PS)were synthesized,and the nanocomposites derived from varied mass fractions of EP and CNT@Ni-PS were prepared.The morphological structures,tribological performances,curing behaviors and thermal properties of EP/CNT@Ni-PS nanocomposites were carefully investigated.Results show that hierarchical CNT nanohybrids with homogeneous dispersion and well-bonded interfacial adhesion in the matrix are successfully obtained,presenting significantly improved thermal and tribological properties.Moreover,analysis on cure kinetics proves the excellent promotion of CNT@Ni-PS on the non-isothermal curing process,lowering the curing energy barrier steadily.
文摘Fig.7(a,a')on page 1289:It has come to our attention that the SEM picture of Fig.7(a,a')for the worn surface of pure EP are misused,because it has been reported in our previous work and was chosen accidentally to denote as the same control sample prepared using the exactly same procedure.The corrected Fig.7(a,a')is shown below.The data analysis,description and conclusion are not affected by this unintentional error.
