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FLAC^(3D)中锚杆剪切破断失效的实现及应用

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岩石力学与工程学报 2017年第8期36卷 1899-1909页

作者：宋远霸闫帅柏建彪郝胜鹏陈勇中国矿业大学矿业工程学院江苏徐州221116 中国矿业大学煤炭资源与安全开采国家重点实验室江苏徐州221116

为解决FLAC^(3D)中无法实现锚杆剪切破断失效的问题,基于PILE结构单元提出锚杆剪切破断判据Fs(i)≥Fsmax(i),采用Fish编程语言二次开发,建立PILE结构单元杆体修正力学模型,并嵌入到FLAC^(3D)主程序中。分别采用PILE单元杆体原模型和修... 详细信息

为解决FLAC^(3D)中无法实现锚杆剪切破断失效的问题,基于PILE结构单元提出锚杆剪切破断判据Fs(i)≥Fsmax(i),采用Fish编程语言二次开发,建立PILE结构单元杆体修正力学模型,并嵌入到FLAC^(3D)主程序中。分别采用PILE单元杆体原模型和修正力学模型,进行杆体剪切实验和煤岩交界面滑移情况下的锚杆支护实验对比分析,结果表明:(1)修正模型杆体剪切荷载–位移曲线呈现出剪切破断失效的特性,达到了以剪力为判据的定量破断,且破断部位结构单元剪力和轴力在发生剪切破断后均突变为零,实现了FLAC^(3D)主程序中锚杆剪切破坏。(2)采用修正模型的锚杆支护方案中,煤岩交界面附近杆体发生剪切破断,且煤–底板交界面附近杆体破断先于煤—顶板交界面附近杆体;煤岩交界面最大滑移量比原模型大17.5 mm,结果更接近实际。(3)PILE修正单元剪切破断失效的实现扩展了FLAC^(3D)的应用范围。

关键词：岩土工程锚杆 FLAC^3D二次开发 PILE结构单元修正力学模型剪切破断失效

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沿空留巷巷旁充填体对拉锚杆加固机理研究

采矿与安全工程学报 2018年第6期35卷 1129-1134页

作者：陈勇杨玉贵闫帅郝胜鹏曹其嘉中国矿业大学煤炭资源与安全开采国家重点实验室矿业工程学院江苏徐州221116 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 蒙得利尔理工学院土木、地质和采矿工程系加拿大魁北克H3C3A7

针对高水材料巷旁充填沿空留巷充填体大变形的问题,通过建立沿空留巷巷旁充填体加固力学模型和基于UDEC 6.0 Trigon网格划分方法的数值模型,得到对拉锚杆、钢筋网等构件对充填体的加固机理,表现为“三大两小”:随着充填体的压缩变形,加... 详细信息

针对高水材料巷旁充填沿空留巷充填体大变形的问题,通过建立沿空留巷巷旁充填体加固力学模型和基于UDEC 6.0 Trigon网格划分方法的数值模型,得到对拉锚杆、钢筋网等构件对充填体的加固机理,表现为“三大两小”:随着充填体的压缩变形,加固构件对其围压增大,充填体内垂直应力集中面积增大,最大承载能力增大20.3%,两帮变形及顶底角鼓包减小,内部错动开裂减小;对拉锚杆和钢筋网的加固作用在充填体大变形情况下尤为明显,使其更好地适应巷道围岩剧烈变形。

关键词：沿空留巷充填体对拉锚杆大变形加固机理

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沿空留巷巷旁充填体稳定性控制技术研究

煤炭科学技术 2019年第9期47卷 273-278页

作者：陈勇孟宁康杨玉贵郝胜鹏中国矿业大学煤炭资源与安全开采国家重点实验室江苏徐州221116 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 Polytechnique Montreal CivilGeological and Mining EngineeringQuebec CanadaH3C3A7

充填体稳定性控制是沿空留巷成功的关键因素之一。为获得合理的充填体稳定性控制技术,以三河尖煤矿7136工作面千米深井沿空留巷为工程背景,采用UDEC6.0的Trigon模型校正了巷旁充填体(高水材料水灰比为1.5∶1.0)的数值模型,然后对充填体... 详细信息

充填体稳定性控制是沿空留巷成功的关键因素之一。为获得合理的充填体稳定性控制技术,以三河尖煤矿7136工作面千米深井沿空留巷为工程背景,采用UDEC6.0的Trigon模型校正了巷旁充填体(高水材料水灰比为1.5∶1.0)的数值模型,然后对充填体稳定控制的钢筋梯子梁直径、对拉锚杆直径及数量不同时的充填体应力应变进行了模拟分析。研究结果表明:充填体的加固作用可有效约束充填体表面位移,综合提升充填体的承载能力可达20%以上,提高了沿空留巷充填体的稳定性,特别是增加对拉锚杆直径和数量在大变形的条件下可有效控制充填体帮部的整体横向变形和鼓包现象,是提高充填体加固系统护表能力、充填体承载能力的重要参数之一。研究成果成功应用于千米深井沿空留巷,加固后的充填体帮平均变形不超过150mm,顶板下沉量不超过250mm,表明充填体加固系统可靠,而且具有良好的适应性。

关键词：沿空留巷充填体对拉锚杆钢筋梯子梁

带有导向孔的浅孔爆破在留巷切顶卸压中的应用研究

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采矿与安全工程学报 2015年第2期32卷 253-259页

作者：陈勇郝胜鹏陈延涛张自政武立飞刘洪林中国矿业大学煤炭资源与安全开采国家重点实验室、深部煤炭资源开采教育部重点实验室、矿业工程学院江苏徐州221116

厚层坚硬顶板切顶卸压是优化沿空留巷围岩应力和结构有效途径之一,将导向孔应用到切顶卸压中是新的尝试。基于浅孔爆破沿空留巷切顶卸压机制,利用LS-DYNA数值模拟与理论分析相结合的方法,分析了导向孔作用机理,探究了参数选取对爆破效... 详细信息

厚层坚硬顶板切顶卸压是优化沿空留巷围岩应力和结构有效途径之一,将导向孔应用到切顶卸压中是新的尝试。基于浅孔爆破沿空留巷切顶卸压机制,利用LS-DYNA数值模拟与理论分析相结合的方法,分析了导向孔作用机理,探究了参数选取对爆破效果的影响。研究结果表明:导向孔增加了自由面,对炮孔连线方向上的切向应力影响明显,提高了炮孔间裂隙贯通率和炸药能量利用率;装药孔不耦合系数取1.31时可充分发挥导向孔应力集中效应;最大切向拉应力与导向孔直径呈正变关系,但对远离导向孔的位置影响微小。根据岩石的动态抗拉强度,确定装药孔间距1.2 m。

关键词：导向孔沿空留巷浅孔爆破切顶卸压

采空区煤柱下沿空留巷围岩破坏特征和控制技术研究

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中国煤炭 2015年第7期41卷 58-61页

作者：徐军郝胜鹏杨建雄白宇扬州工业职业技术学院江苏省扬州市225127 中国矿业大学煤炭资源与安全开采国家重点实验室江苏省徐州市221116

中兴煤矿1204下工作面开采2#下煤层,与2#煤层间距3m左右,巷道顶板薄、破碎,基于中兴煤矿1204下工作面材料巷沿空留巷工程实践,结合UDEC数值模拟对采空区煤柱下沿空留巷围岩破坏特征进行了研究,并提出用短锚索对巷道进行支护,取得了良好... 详细信息

中兴煤矿1204下工作面开采2#下煤层,与2#煤层间距3m左右,巷道顶板薄、破碎,基于中兴煤矿1204下工作面材料巷沿空留巷工程实践,结合UDEC数值模拟对采空区煤柱下沿空留巷围岩破坏特征进行了研究,并提出用短锚索对巷道进行支护,取得了良好的效果。

关键词：采空区煤柱沿空留巷围岩控制巷道支护 UDEC模拟短锚索

Preparation of Low Ratio Magnesium Ccement by Acid Leaching Treatment of Boron Mud

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 120-129页

作者： YANG Mei ZHANG Mingzhe CHEN hao School of Materials Science and Engineering Shenyang Jianzhu UniversityShenyang 110168China School of Physical Science and Technology Shenyang Normal UniversityShenyang 110168China

The effects of liquid-solid ratio and reaction time on the leaching rate of magnesium at room temperature were investigated,as well as the effects of the molar ratio of MgO/MgCl_(2),the amount of water added,and the amount of acid-impregnated slag dosed on the compressive strength and water resistance of *** results showed that the magnesium element in the boron mud could be maximally leached under the conditions of 1:1 concentration of hydrochloric acid at room temperature,liquid-solid ratio of 2.5 mL·g^(-1),and reaction time of 5 h,and the main products were amorphous SiO_(2) as well as a small amount of magnesium olivine which had not been completely *** LR-MOC prepared using the acid-soaked mixture could reach a softening coefficient of 0.85 for 28 d of water immersion when the molar ratio of MgO/MgCl_(2) was 2.2,the amount of water added was 0 g,and the acid-soaked slag dosing was 40 wt%,which also led to an appreciable late-strength,with an increase of 19.4%in compressive strength at 28 d compared to that at 7 *** previous studies,LR-MOC prepared in this way has a final strength phase that is not the more easily hydrolysed 3-phase but the lath-like *** this phenomenon,we analyzed the mechanism and found that,during the acid leaching process,a part of amorphous SiO_(2) dissolved in the acid leaching solution formed a silica sol,in which Mg^(2+)played a bridging role to make the silica sol more *** the addition and hydrolysis of MgO,the silica sol gel coagulation slows down,providing a capping layer to inhibit the hydrolysis of the 5-phase crystals and providing some strength after *** amorphous SiO_(2) in the other part of the acid-impregnated slag generated M-S-H gel with Mg^(2+)and OH-,which synergised with the dense structure composed of interlocking crystals to improve the water resistance of LR-MOC.

关键词： boron mud magnesium chloride-oxygen cement acid immersion water resistance silica sol

The role of axon guidance molecules in the pathogenesis of epilepsy

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Neural Regeneration Research 2025年第5期20卷 1244-1257页

作者： Zheng Liu Chunhua Pan hao Huang Department of Neurology Affiliated Hospital of Zunyi Medical UniversityZunyiGuizhou ProvinceChina

Current treatments for epilepsy can only manage the symptoms of the condition but cannot alter the initial onset or halt the progression of the disease. Consequently, it is crucial to identify drugs that can target novel cellular and molecular mechanisms and mechanisms of action. Increasing evidence suggests that axon guidance molecules play a role in the structural and functional modifications of neural networks and that the dysregulation of these molecules is associated with epilepsy susceptibility. In this review, we discuss the essential role of axon guidance molecules in neuronal activity in patients with epilepsy as well as the impact of these molecules on synaptic plasticity and brain tissue remodeling. Furthermore, we examine the relationship between axon guidance molecules and neuroinflammation, as well as the structural changes in specific brain regions that contribute to the development of epilepsy. Ample evidence indicates that axon guidance molecules, including semaphorins and ephrins, play a fundamental role in guiding axon growth and the establishment of synaptic connections. Deviations in their expression or function can disrupt neuronal connections, ultimately leading to epileptic seizures. The remodeling of neural networks is a significant characteristic of epilepsy, with axon guidance molecules playing a role in the dynamic reorganization of neural circuits. This, in turn, affects synapse formation and elimination. Dysregulation of these molecules can upset the delicate balance between excitation and inhibition within a neural network, thereby increasing the risk of overexcitation and the development of epilepsy. Inflammatory signals can regulate the expression and function of axon guidance molecules, thus influencing axonal growth, axon orientation, and synaptic plasticity. The dysregulation of neuroinflammation can intensify neuronal dysfunction and contribute to the occurrence of epilepsy. This review delves into the mechanisms associated with

关键词： axon guidance drug-resistant epilepsy epilepsy nerve regeneration nervous system diseases neural pathways neuroinflammatory diseases neuronal plasticity neurons synaptic remodeling

Gradient‑Layered MXene/Hollow Lignin Nanospheres Architecture Design for Flexible and Stretchable Supercapacitors

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Nano-Micro Letters 2025年第2期17卷 447-462页

作者： haonan Zhang Cheng hao Tongtong Fu Dian Yu Jane Howe Kaiwen Chen Ning Yan hao Ren Huamin Zhai Jiangsu Provincial Key Lab of Sustainable Pulp and Paper Technology and Biomass Materials NanJing Forestry UniversityNanjing 210037People’s Republic of China Department of Chemical Engineering and Applied Chemistry University of Toronto200 College StreetTorontoON M5S 3E5Canada Department of Materials Science and Engineering University of Toronto184 College StreetTorontoON M5S 3E4Canada College of Materials Science and Engineering Nanjing Forestry UniversityNanjing 210037People’s Republic of China

With the rapid development of flexible wearable electronics,the demand for stretchable energy storage devices has *** this work,a novel gradient-layered architecture was design based on single-pore hollow lignin nanospheres(HLNPs)-intercalated two-dimensional transition metal carbide(Ti_(3)C_(2)T_(x) MXene)for fabricating highly stretchable and durable *** depositing and inserting HLNPs in the MXene layers with a bottom-up decreasing gradient,a multilayered porous MXene structure with smooth ion channels was constructed by reducing the overstacking of MXene ***,the micro-chamber architecture of thin-walled lignin nanospheres effectively extended the contact area between lignin and MXene to improve ion and electron accessibility,thus better utilizing the pseudocapacitive property of *** these strategies effectively enhanced the capacitive performance of the *** addition,HLNPs,which acted as a protective phase for MXene layer,enhanced mechanical properties of the wrinkled stretchable electrodes by releasing stress through slip and deformation during the stretch-release cycling and greatly improved the structural integrity and capacitive stability of the *** electrodes and symmetric flexible all-solid-state supercapacitors capable of enduring 600%uniaxial tensile strain were developed with high specific capacitances of 1273 mF cm^(−2)(241 F g^(−1))and 514 mF cm^(−2)(95 F g^(−1)),***,their capacitances were well preserved after 1000 times of 600%stretch-release *** study showcased new possibilities of incorporating biobased lignin nanospheres in energy storage devices to fabricate stretchable devices leveraging synergies among various two-dimensional nanomaterials.

关键词： Hollow lignin nanospheres MXene Gradient-layered architecture Wrinkled electrodes Stretchable supercapacitors

Laser‑Induced Highly Stable Conductive Hydrogels for Robust Bioelectronics

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Nano-Micro Letters 2025年第3期17卷 117-120页

作者： Yibo Li hao Zhou Huayong Yang Kaichen Xu State Key Laboratory of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou 310058People’s Republic of China

Despite the promising progress in conductive hydrogels made with pure conducting polymer,great challenges remain in the interface adhesion and robustness in longterm *** address these challenges,*** Hwan Ko and Taek-Soo Kim’s team introduced a laserinduced phase separation and adhesion method for fabricating conductive hydrogels consisting of pure poly(3,4-ethylenedioxythiophene):polystyrene sulfonate on polymer *** laser-induced phase separation and adhesion treated conducting polymers can be selectively transformed into conductive hydrogels that exhibit wet conductivities of 101.4 S cm^(−1)with a spatial resolution down to 5μ***,they maintain impedance and charge-storage capacity even after 1 h of *** micropatterned electrode arrays demonstrate their potential in long-term in vivo signal recordings,highlighting their promising role in the field of bioelectronics.

关键词： Laser processing Conductive hydrogels Stable interface Bio-interfacing electrodes Bioelectronic application