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Numerical simulation of the effect of coupling support of bolt-mesh-anchor in deep tunnel

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Mining Science and Technology 2009年第3期19卷 352-357页

作者： sun xiao-ming CAI Feng YANG Jun CAO Wu-fu School of Mechanics and Civil Engineering China University of Mining ＆ Technology Beijing 100083 China State Key Laboratory for Geomechanics and Deep Underground Engineering Beijing 100083 China Beijing Track-Traffic Construction Management Limited Company Beijing 100037 China

The mechanical effects of bolt-mesh-anchor coupling support in deep tunnels were studied by using a numerical method, based on deep tunnel coupling supporting techniques and non-linear deformation mechanical theory of rock mass at great *** is shown that the potential of a rigid bolt support can be efficiently activated through the coupling effect between a bolt-net support and the surrounding *** is found that the accumulated plastic energy in the surrounding rock can be sufficiently transformed by the coupling effect of a bolt-mesh-tray *** strength of the surrounding rock mass can be mobilized to control the deforma-tion of the surrounding rock by a pre-stress and time-space effect of the anchor *** high stress transformation effect can be realized by the mechanical coupling effect of the bolt-mesh-anchor support, whereby the force of the support and deformation of the surrounding rock tends to become uniform, leading to a sustained stability of the tunnel.

关键词： mining engineering deep tunnel non-linear large deformation mechanics bolt-mesh-anchor support coupling support effect

Supporting characteristics analysis of constant resistance bolts under coupled static-dynamic loading

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Journal of Mountain Science 2019年第5期16卷 1160-1169页

作者： CHEN Feng TANG Chun-an sun xiao-ming MA Tian-hui DU Yan-hong School of Civil Engineering Dalian University of Technology State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and Technology School of Mechanics and Engineering Liaoning Technical University

To study the tensile mechanical properties of constant resistance bolts, the RFPA(Rock Failure Process Analysis) statics software is used to perform a uniaxial tensile test on a constant resistance bolt. The numerical test results show that the plastic strain value is 12 times the magnitude of the elastic strain. During plastic deformation, the fluctuation in the stress magnitude is relatively stable, indicating that the bolt has good constant resistance characteristics. The numerical test results are in good agreement with the laboratory test results of M.C. He, and the accuracy and reliability of the numerical test method are verified. Therefore, the RFPA software with coupled static-dynamic loading is further adopted to study the supporting effects of traditional bolts and constant resistance bolts under coupled staticdynamic loading. The numerical comparison of the test results show that the constant resistance bolts can effectively control the deformation amount and rate of the laneway surrounding rock, reduce the total and rate of increase in the accumulated acoustic emissions,decrease the stress on the units in the model and protect the stability of the laneway. This paper verifies that a constant resistance bolt has better impact resistance mechanical properties than those of a traditional bolt and provides an effective way to control rock burst and soft rock that is prone to large deformation damage.

关键词： Rock mechanics Coupled static-dynamic loading Deep laneway Constant resistance bolt RFPA

Analysis of blasting vibration signal of high steep anti-dip layered rock slope

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Journal of Mountain Science 2022年第11期19卷 3257-3269页

作者： sun xiao-ming PANG Shi-hui QIN Ke SHITing-ting ZHU Chun TAO Zhi-gang State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining&Technology(Beijing)Beijing 100083China School of Mechanics and Civil Engineering China University of Mining&Technology(Beijing)Beijing 100083China College of Earth Science and Engineering Hohai UniversityNanjing 210098China

Blasting is one of the most economical and efficient mining methods in open-pit mine ***,behind the huge benefits,it poses a hidden threat to the quality of slope rock mass,stability of slope,and safety of nearby *** order to explore the influence of blasting vibration on the stability of anti-dip layered rock slopes,herein,the site near the large-scale toppling failure area of Changshanhao gold mine stope of Inner Mongolia Taiping Mining Co.,*** selected for on-site blasting test and *** Peak Particle Velocity(PPV)measured at the monitoring point is located on the lower side of the maximum allowable vibration velocity curve that is prepared based on the allowable speed standard evaluation chart in the full frequency domain established by standards practiced in various countries such as German DIN4150,the USBM RI 8507,and Chinese *** indicates that the blasting vibration has less influence on the location of the monitoring *** vibration signals obtained in the blasting test were analyzed using the wavelet packet theory,and it was concluded that the blasting vibration signals measured in the anti-dip layered rock slope were mainly concentrated in two frequency bands of 0-80 Hz and 115-160 *** sum of energy of the two frequency bands accounted for more than 99%,wherein,the energy contained in the 0-80 Hz frequency band accounted for more than 85%of the monitoring *** vibration signal with 0-80 Hz frequency band monitored at the slope toe was selected for the energy attenuation *** results showed that the energy attenuation decreased in radial,vertical,and tangential ***,the Energy Attenuation Rate per Meter(EARPM)was *** conjunction with the site characteristics analysis,it was found that the energy attenuation rate was significantly affected by the rock mass characteristics of the structural *** slope reinforcement project can effectively reduce the absorption

关键词： Anti-dip rocky slope Blasting vibration PPV Wavelet packet theory EARPM

Numerical simulation of rockburst disaster and control strategy of constant resistance and large deformation anchor cable in Gaoloushan tunnel

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Journal of Mountain Science 2023年第6期20卷 1605-1619页

作者： MIAO Cheng-yu JIANG ming LI Zhi-hu sun xiao-ming ZHANG Tong ZHANG Yong YANG Jin-kun REN Chao SONG Peng State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and Technology(Beijing)Beijing 100083China School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing 100083China School of Civil Engineering Nanyang Institute of TechnologyNanyang 473000China

The Gaoloushan Tunnel in Longnan City,Gansu Province,China,frequently experiences rockburst disasters due to high in-situ *** rockburst in deep-buried tunnels remains a challenging *** paper employs RFPA(Rock Failure Process Analysis)software to establish a calculation model of constant resistance and large deformation(CRLD)anchorages and analyzes the effects of different support methods and pre-stress levels on *** simulate the process of tunnel rockburst disasters and find that ordinary anchor support incurs rockburst on the right arch waist and arch top,forming a V-shaped explosion *** anchor support has several advantages in rockburst control,such as more uniform stress distribution in the surrounding rock,a uniform distribution of plastic zones,less noticeable damage to the tunnel,and effective control of the arch top *** effectiveness of the CRLD anchor support under varying pre-stress conditions shows that a higher prestress results in a smaller plastic zone of the surrounding rock and arch top displacement and a lower number of acoustic emission signals,which better explains the excavation compensation ***,adding long anchorages in the deep surrounding rock area can better control rockburst and reduce surrounding rock *** on these findings,we propose a comprehensive control system that combines long and short anchorages and provides the optimal scheme based on ***,by using high-prestress CRLD anchor support and the combination of long and short anchorages at critical positions,we can enhance the integrity of the surrounding rock,effectively absorb the energy released by the surrounding rock deformation,and reduce the incidence of rockburst disasters.

关键词： Tunnel Rockburst RFPA Constant Resistance and Large Deformation anchor cable Long and short cable coupling support.

Failure mechanism and control countermeasures of surrounding rock at deep large section chamber intersection in the Wanfu Coal Mine

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Journal of Mountain Science 2023年第7期20卷 2058-2075页

作者： sun xiao-ming QI Zhen-min ZHANG Yong MIAO Cheng-yu ZHAO Cheng-wei HE Man-chao State Key Laboratory for GeoMechanics and Deep Underground Engineering China University of Mining&Technology BeijingBeijing 100083China School of Mechanics and Civil Engineering China University of Mining&Technology-BeijingBeijing 100083China Institute of Rock and Soil Mechanics Chinese Academy of SciencesWuhan 430060China

In order to solve the problem of large deformation at the intersection of deep large section soft rock roadway,this paper takes the intersection of kilometer-deep roadway in the Wanfu Coal Mine as an engineering example and applies Negative Poisson’s Ratio(NPR)steel anchor cable in roadway support for the first *** combining numerical simulation indoor test,theoretical analysis and field test,the deformation mechanism of surrounding rock at the intersection of deep-buried roadway was analyzed,and the control strategy with micro NPR steel anchor cable as the core was put *** numerical simulation,the numerical analysis model of roadway intersection with different intersection angles and excavation sequence was constructed,and the impact of two key variables of rake angle and excavation sequence on the stability of surrounding rock at roadway intersection was *** optimal dip angle is 90°and the optimal excavation sequence was determined as pump house-pump house *** mechanical properties of the micro-NPR steel anchor cable were studied through the static tensile test in the *** results showed that the micro-NPR steel anchor cable showed high constant resistance,uniform tensile,no yield platform,and no obvious necking phenomenon during *** theoretical derivation,it was calculated that the vertical stress of roadway intersection is 45 MPa,and the bearing capacity of superposed arch composed of micro NPR steel anchor cable is 1257 kN,which is enough to guarantee the overall stability of *** application test and monitoring were carried out on site,and it was verified that the combined support strategy of short and long micro NPR steel anchor cable has a good control effect on large deformation of surrounding rock at intersection,which provides a new support material and support means for the safety and stabilization control of surrounding rock at intersection.

关键词： Mountain tunnel Composite lining Surrounding rock grade Force variation Primary support Secondary lining

Effect of in ovo zinc injection on the embryonic development, tissue zinc contents, antioxidation, and related gene expressions of broiler breeder eggs

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Journal of Integrative Agriculture 2018年第3期17卷 648-656页

作者： sun xiao-ming LIAO Xiu-dong LU Lin ZHANG Li-yang MA Qiu-gang XI Lin LUO Xu-gang Mineral Nutrition Research Division Institute of Animal Science Chinese Academy of Agricultural Sciences College of Animal Science and Technology China Agricultural University Department of Animal Science North Carolina State University

Two experiments were conducted to investigate the effect of in ovo zinc （Zn） injection on the embryonic development, tissue Zn contents, antioxidation and related gene expressions of fertilized eggs of Arbor Acres broiler breeders. Experiment 1 was conducted to determine an optimal embryonic age for early in ovo injection. A total of 720 fertilized eggs with similar weights were randomly allotted to 4 treatments with 6 replicates per treatment and 30 eggs per replicate in a completely randomized design. The eggs were injected with 0.1 mL sterilized water at 3, 6 and 9 embryonic days of incubation （E3, E6 and E9） or non-injection （the control）, respectively. The results from experiment 1 showed that E3 and E6 injections increased （P〈0.05） the embryonic mortalities, and decreased （P〈0.05） hatchabilities compared to the non-injected control, but no differences （P〉0.05） between E9 injection and the non-injected control were observed in either embryonic mortality or hatchability. The findings suggest that the E9 is the optimal embryonic age for early in ovo injection. In experiment 2, a total of 672 fertilized eggs with similar weights were randomly allocated to 7 treatments with 6 replicates per treatment and 16 eggs per replicate in a completely randomized design. The eggs were injected with 0 （the negative control）, 50, 100, 150, 200, or 250 μg Zn/egg as reagent grade ZnSO4.7H20 in a 0.1-mL solution, or non-injection （the positive control）, respectively at E9-10. The results from the experiment 2 demonstrated that no differences （P〉0.05） among 50 and 100 μg Zn/egg groups and the negative control were observed in the embryonic mortality and hatchability, however, the injection of 200 μg Zn/egg increased （P〈0.05） the embryonic mortality, and injections of 150 and 200 μg Zn/egg decreased （P〈0.05） hatchabilities compared with the controls. The embryonic tibia Zn contents at E20 were increased （P〈0.05） by injections of 150, 200 and 250μg Zn/egg. Zinc injection did not affe

关键词： in ovo injection zinc embryonic development gene expression broiler breeder egg

Stability control measures for roof cutting and NPR supporting of mining roadways in fault areas of kilometre-deep coal mine

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Journal of Mountain Science 2023年第10期20卷 3051-3065页

作者： sun xiao-ming WANG Jian ZHANG Yong ZHAO Wen-chao GUO Zhi-biao HE Man-chao CHEN Feng MIAO Cheng-yu State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and Technology(Beijing)Beijing 100083China School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing 10oo83China School of Civil Engineering Nanyang Institute of TechnologyNanyang 4730ooChina

The study focuses on the stability control measures for mining roadways in fault zones of deep mines,using Daqiang Coal Mine as a case *** control system under consideration,referred to as"pre-splitting cutting roof+NPR anchor cable"(PSCR-NPR),is subjected to scrutiny through theoretical analysis,numerical modelling,and field ***,a comprehensive analysis is undertaken to evaluate the stability control mechanism of this particular *** study provides evidence that the utilization of deep-hole directional energy-concentrated blasting facilitates the attainment of directional roof cutting in *** aforementioned procedure leads to the formation of a uniform structural surface on the roof of the roadway and causes modifications in the surrounding geological *** examination of the lateral abutment pressure and shear stress distribution,both prior to and subsequent to roof cutting,indicates that the implementation of pre-splitting techniques leads to a noteworthy reduction in *** proposition of incorporating the safety factor Q for roof cutting height is suggested as a method to augment comprehension of the pressure relief phenomenon in the field of *** analysis of numerical simulation has indicated that the optimal pressure relief effect of a mining roadway in a fault area is attained when the value of Q is *** NPR anchor cable exhibits noteworthy characteristics,including a high level of prestress,continuous resistance,and substantial *** the excavation of the roadway,a notable reduction in radial stress occurs,leading to the reinstatement of the three-phase stress state in the surrounding *** restoration is attributed to the substantial prestress exerted on the radial *** termination point of the NPR anchor cable is strategically positioned within a stable rock formation,allowing for the utilization of the mechanical characteristics of the deep stable rock *** posi

关键词： Kilometre-deep mine Fault Mining roadway Pre-splitting cutting roof High pre-stress NPR anchor cable

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多种物品三维装箱问题的一种启发式算法

上海交通大学学报 2007年第8期41卷 1244-1247页

作者：翟钰孙小明上海交通大学工业工程与管理系上海200240

针对多种物品单箱三维装箱的问题,设计了一种新的启发式算法.该算法基于"平面"和"块"的概念,采取树搜索策略,允许货物在任何可行方向上旋转,在保证箱空间利用率足够高的同时,满足货物摆放稳定性的要求.实验结果表明,该算法是解决此类问... 详细信息

针对多种物品单箱三维装箱的问题,设计了一种新的启发式算法.该算法基于"平面"和"块"的概念,采取树搜索策略,允许货物在任何可行方向上旋转,在保证箱空间利用率足够高的同时,满足货物摆放稳定性的要求.实验结果表明,该算法是解决此类问题的一种有效的方法.

关键词：三维装箱问题物流配送启发式算法

测量爆炸火焰真温的多光谱温度计的研制--现场实验与测量精度分析

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光谱学与光谱分析 2013年第6期33卷 1719-1722页

作者：孙崐孙晓刚于晓洋孙晓明哈尔滨理工大学测控技术与仪器黑龙江省高校重点实验室黑龙江哈尔滨150080 哈尔滨理工大学工程电介质及其应用技术教育部重点实验室黑龙江哈尔滨150080 哈尔滨工业大学

研制了可用于大型爆炸现场的、测量爆炸火焰真温的多光谱温度计(量程为800～3 500℃,波长范围为0.6～1.1μm)。测量原理进一步改进,加入亮温逼近法解决了二次测量法初值选取困难的问题,并应用此高温计在空旷场地对3kg TNT炸药爆炸的全... 详细信息

研制了可用于大型爆炸现场的、测量爆炸火焰真温的多光谱温度计(量程为800～3 500℃,波长范围为0.6～1.1μm)。测量原理进一步改进,加入亮温逼近法解决了二次测量法初值选取困难的问题,并应用此高温计在空旷场地对3kg TNT炸药爆炸的全过程进行测量。通过实验结果的分析可知,此高温计可以测量爆炸火焰真温变化全过程,对波阵面瞬时温度与燃烧火球温度的测量均具有很好的效果。同时,分析了影响此高温计测量精度的各个因素,得出目前制约多光谱高温计测量精度提高的主要因素仍然为真温算法及标定方法的误差,这为今后研制高精度高温计明确了方向。

关键词：多光谱爆炸火焰真温测量 TNT 测量不确定度