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An experimental study of a yielding support for roadways constructed in deep broken soft rock under high stress 被引量:7
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作者 Lu Yinlong Wang Lianguo Zhang Bei 《Mining Science and Technology》 EI CAS 2011年第6期839-844,共6页
A rationally designed support for deep roadways excavated in broken soft rock under high stress was investigated. The deformation and failure characteristics and the mechanism of ''yielding support'' w... A rationally designed support for deep roadways excavated in broken soft rock under high stress was investigated. The deformation and failure characteristics and the mechanism of ''yielding support'' was studied for anchor bolts and cables. The rail roadway of the 2-501 working face in the Liyazhuang Mine of the Huozhou coal area located in Shanxi province was used for field trials. The geological conditions used there were used during the design phase. The new ''highly resistant, yielding'' support system has a core of high strength, yielding bolts and anchor cables. The field tests show that this support system adapts well to the deformation and pressure in the deep broken soft rock. The support system effectively controls damage to the roadway and ensures the long term stability of the wall rock and safe production in the coal mine. This provides a remarkable economic and social benefit and has broad prospects for fur- ther application. 展开更多
关键词 High stress Broken soft rock Roadways Yielding support Yielding anchor bolt
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SOFT SENSING MODEL BASED ON SUPPORT VECTOR MACHINE AND ITS APPLICATION 被引量:3
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作者 YanWeiwu ShaoHuihe WangXiaofan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2004年第1期55-58,共4页
Soft sensor is widely used in industrial process control. It plays animportant role to improve the quality of product and assure safety in production. The core of softsensor is to construct soft sensing model. A new s... Soft sensor is widely used in industrial process control. It plays animportant role to improve the quality of product and assure safety in production. The core of softsensor is to construct soft sensing model. A new soft sensing modeling method based on supportvector machine (SVM) is proposed. SVM is a new machine learning method based on statistical learningtheory and is powerful for the problem characterized by small sample, nonlinearity, high dimensionand local minima. The proposed methods are applied to the estimation of frozen point of light dieseloil in distillation column. The estimated outputs of soft sensing model based on SVM match the realvalues of frozen point and follow varying trend of frozen point very well. Experiment results showthat SVM provides a new effective method for soft sensing modeling and has promising application inindustrial process applications. 展开更多
关键词 soft sensor soft sensing MODELING support vector machine
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A study of support strategies in deep soft rock:The horsehead crossing roadway in Daqiang Coal Mine 被引量:14
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作者 Guo Zhibiao Yang Xiaojie +2 位作者 Bai Yunpeng Zhou Feng Li Erqiang 《International Journal of Mining Science and Technology》 SCIE EI 2012年第5期665-667,共3页
Geomechanics in deep mines becomes more complex and structural support in soft rock can be very difficult.Highly stressed soft rock subject to expansion deformation is particularly difficult to control.The Tiefa Coal ... Geomechanics in deep mines becomes more complex and structural support in soft rock can be very difficult.Highly stressed soft rock subject to expansion deformation is particularly difficult to control.The Tiefa Coal Industry Group Daqiang Coal Mine is used as an example.A ventilation shaft,à550 horsehead,is located in tertiary soft rock.Analysis of the reasons for deformation shows an intumescent rock,which is easily damaged.Field observations and theoretical analysis led to a design capable of stabilizing the rock.A combination of spray,anchors,anchor bolts,and soft corner coupled truss supports allowed the deformation to be controlled.This provides a model for similar designs when support of a horsehead roadway is required. 展开更多
关键词 Deep well soft rock Horsehead Deformation mechanical mechanism Coupling support
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Improvement of the prediction performance of a soft sensor model based on support vector regression for production of ultra-low sulfur diesel 被引量:2
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作者 Saeid Shokri Mohammad Taghi Sadeghi +1 位作者 Mahdi Ahmadi Marvast Shankar Narasimhan 《Petroleum Science》 SCIE CAS CSCD 2015年第1期177-188,共12页
A novel data-driven, soft sensor based on support vector regression (SVR) integrated with a data compression technique was developed to predict the product quality for the hydrodesulfurization (HDS) process. A wid... A novel data-driven, soft sensor based on support vector regression (SVR) integrated with a data compression technique was developed to predict the product quality for the hydrodesulfurization (HDS) process. A wide range of experimental data was taken from a HDS setup to train and test the SVR model. Hyper-parameter tuning is one of the main challenges to improve predictive accuracy of the SVR model. Therefore, a hybrid approach using a combination of genetic algorithm (GA) and sequential quadratic programming (SQP) methods (GA-SQP) was developed. Performance of different optimization algorithms including GA-SQP, GA, pattern search (PS), and grid search (GS) indicated that the best average absolute relative error (AARE), squared correlation coefficient (R2), and computation time (CT) (AARE = 0.0745, R2 = 0.997 and CT = 56 s) was accomplished by the hybrid algorithm. Moreover, to reduce the CT and improve the accuracy of the SVR model, the vector quantization (VQ) technique was used. The results also showed that the VQ technique can decrease the training time and improve prediction performance of the SVR model. The proposed method can provide a robust, soft sensor in a wide range of sulfur contents with good accuracy. 展开更多
关键词 soft sensor support vector regression Hybrid optimization method Vector quantization Petroleum refinery Hydrodesulfurization process Gas oil
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Optimization of construction scheme and supporting technology for HJS soft rock tunnel 被引量:10
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作者 Wang Shuren Li Chunliu +1 位作者 Liu Zhaowei Fang Junbo 《International Journal of Mining Science and Technology》 SCIE EI 2014年第6期847-852,共6页
For a soft rock tunnel under high stress in jointed and swell soft rock (HJS), two construction schemes pilot-tunneling enlarging excavation and step-by-step excavation were optimized using FLAC20, and the deformati... For a soft rock tunnel under high stress in jointed and swell soft rock (HJS), two construction schemes pilot-tunneling enlarging excavation and step-by-step excavation were optimized using FLAC20, and the deformation effects of the two construction schemes were verified by field tests. Based on engineer- ing geological investigation and mechanical analysis of large deformations, the complex deformation mechanisms of stress expansion and structural deformation of the soft rock tunnel were confirmed, and support countermeasures from the complex deformation mechanism converted to a single type were proposed, and the support parameters were optimized by field tests. These technologies were proved by engineering practice, which produced significant technical and economic benefits. 展开更多
关键词 soft rock tunnel High stress Deformation mechanism support parameters Optimization
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Numerical simulation of creep characteristics of soft roadway with bolt-grouting support 被引量:5
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作者 王连国 李海亮 张健 《Journal of Central South University》 SCIE EI CAS 2008年第S1期391-396,共6页
Based on the engineering background of a soft rock roadway in Qinan Coal Mine 82 Area,Huaibei Mining Group,three creep models with different support patterns in soft rock roadway were established by using geotechnical... Based on the engineering background of a soft rock roadway in Qinan Coal Mine 82 Area,Huaibei Mining Group,three creep models with different support patterns in soft rock roadway were established by using geotechnical software of FLAC2D.According to the calculation results of different models,the change law of mechanical properties with the time of bolt-grouting support structure was obtained.Furthermore,for the test bolt-grouting support roadway,the deformation law of surrounding rock got by underground industrial experiment and field observation accords with the creep law got by numerical calculation.The results of numerical calculation and field observation show that,compared with other supports,the creep of bolt-grouting support roadway enters the steady-state creep stage from tertiary creep stage ahead,the deformations of roof,floor and two sides are decreased greatly,the plastically deforming area in surrounding rock is reduced obviously,and the distribution ranges of maximum and minimum principal stress are shrank obviously.All those fully show that the bolt-grouting support has its remarkable advantages in controlling surrounding rock creep and improving the whole strength of surrounding rock and self-bearing capacity. 展开更多
关键词 soft ROCK BOLT-GROUTING support CREEP NUMERICAL simulation engineering practice
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Bolt-grouting combined support technology in deep soft rock roadway 被引量:15
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作者 Chen Yanlong Meng Qingbin +2 位作者 Xu Guang Wu Haoshuai Zhang Guimin 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第5期777-785,共9页
Analyzing the mineral composition, mechanical properties and ground stress testing in surrounding rock,the study investigated the failure mechanism of deep soft rock roadway with high stress. The boltgrouting combined... Analyzing the mineral composition, mechanical properties and ground stress testing in surrounding rock,the study investigated the failure mechanism of deep soft rock roadway with high stress. The boltgrouting combined support system was proposed to prevent such failures. By means of FLAC3D numerical simulation and similar material simulation, the feasibility of the support design and the effectiveness of support parameters were discussed. According to the monitoring the surface and deep displacement in surrounding rock as well as bolt axial load, this paper analyzed the deformation of surrounding rock and the stress condition of the support structure. The monitor results were used to optimize the proposed support scheme. The results of field monitors demonstrate that the bolt-grouting combined support technology could improve the surround rock strength and bearing capacity of support structure, which controlled the great deformation failure and rheological property effectively in deep soft rock roadway with high stress. As a result, the long term stability and safety are guaranteed. 展开更多
关键词 Deep soft rock roadway Bolt-grouting support Numerical simulation Similar material simulation High stress
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Discussion on Reasonable Supporting Parameters for Repairing Underground Projects in Bulking Soft Rock
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作者 宋宏伟 《International Journal of Mining Science and Technology》 SCIE EI 1999年第1期18-21,共4页
Based on analysis of the supporting object of bulking soft rock and comparing the supporting difficulty of the repairing projects with that of the newly excavated projects, this paper proposes a method to determine re... Based on analysis of the supporting object of bulking soft rock and comparing the supporting difficulty of the repairing projects with that of the newly excavated projects, this paper proposes a method to determine reasonable supporting parameters for soft rock project repairing. This method has been verified to be reasonable and economical in an industrial test. 展开更多
关键词 soft ROCK supportING supportING parameter repairing of UNDERGROUND project supportING mechanism broken ROCK ZONE
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Influence of dynamic pressure on deep underground soft rock roadway support and its application 被引量:5
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作者 Meng Qingbin Han Lijun +4 位作者 Chen Yanlong Fan Jiadong Wen Shengyong Yu Liyuan Li Hao 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第5期903-912,共10页
Due to high ground stress and mining disturbance, the deformation and failure of deep soft rock roadway is serious, and invalidation of the anchor net-anchor cable supporting structure occurs. The failure characterist... Due to high ground stress and mining disturbance, the deformation and failure of deep soft rock roadway is serious, and invalidation of the anchor net-anchor cable supporting structure occurs. The failure characteristics of roadways revealed with the help of the ground pressure monitoring. Theoretical analysis was adopted to analyze the influence of mining disturbance on stress distribution in surrounding rock,and the change of stress was also calculated. Considering the change of stress in surrounding rock of bottom extraction roadway, the displacement, plastic zone and distribution law of principal stress difference under different support schemes were studied by means of FLAC3D. The supporting scheme of U-shaped steel was proposed for bottom extraction roadway that underwent mining disturbance. We carried out a similarity model test to verify the effect of support in dynamic pressure. Monitoring results demonstrated the change rules of deformation and stress of surrounding rock in different supporting schemes. The supporting scheme of U-shaped steel had an effective control on deformation of surrounding rock. The scheme was successfully applied in underground engineering practice, and achieved good technical and economic benefits. 展开更多
关键词 Deep soft rock roadway Dynamic pressure impact Similarity model test Combined support Ground pressure monitoring
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深部软岩复合衬砌支护结构室内模型实验及力学效应分析
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作者 杜志强 张金松 +2 位作者 黄嘉玲 朱晓凡 邵良超 《煤》 2026年第2期48-58,64,共12页
以朱集西煤矿1采区为研究对象,基于相似理论构建物理模型试验体系,系统探究不同侧压力系数与埋深耦合作用下围岩应力重分布规律、衬砌内力传递特性及结构损伤扩展模式。试验采用衬砌结构-土压水压复合体模型试验系统,通过X、Y、Z三向独... 以朱集西煤矿1采区为研究对象,基于相似理论构建物理模型试验体系,系统探究不同侧压力系数与埋深耦合作用下围岩应力重分布规律、衬砌内力传递特性及结构损伤扩展模式。试验采用衬砌结构-土压水压复合体模型试验系统,通过X、Y、Z三向独立加载模拟软岩巷道真实应力环境,集成电阻式传感器与应变式土压力盒监测技术,定量分析围岩与支护结构的动态力学响应,结果表明,相似模型能够准确反映围岩-结构协同作用机制,支护加密能够在一定地程度上更约束围岩的变形,从而减少衬砌明显的应力集中现象,该研究可以对朱集西煤矿巷道产生显著的支护效果,特别是在控制围岩变形和抑制应力集中方面,研究结果表明,拱脚支护加密能够有效降低两帮区域峰值,可降低51%,并对底板围岩起到了有效的支护作用。 展开更多
关键词 物理模型 软岩巷道 监测技术 支护加密 应力集中
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隧洞软岩洞段大变形分析及初期支护措施
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作者 姜封国 林抒予 +1 位作者 姜婷玉 韩羽 《黑龙江科技大学学报》 2026年第1期23-28,共6页
为解决高应力软岩隧洞开挖过程中因大变形导致的工程问题,以某水电站引水隧洞工程为对象,依托现场施工揭露的地质现象分析了隧道开挖时部分洞段发生大变形的原因,结合数值模拟手段研究了隧洞围岩变形及塑性区的演化规律,并给出相应的支... 为解决高应力软岩隧洞开挖过程中因大变形导致的工程问题,以某水电站引水隧洞工程为对象,依托现场施工揭露的地质现象分析了隧道开挖时部分洞段发生大变形的原因,结合数值模拟手段研究了隧洞围岩变形及塑性区的演化规律,并给出相应的支护措施。结果表明:隧洞开挖后围岩变形起初随着开挖荷载释放率的增加呈线性增长,到达突变点后,塑性区快速发展,围岩位移呈非线性增长的趋势,易导致隧洞坍塌,在荷载释放率为70%左右时,施加初期支护较为合适;原初期支护强度不能满足稳定性要求,需采取一定的强化措施,调整后锚杆最大受力298.5 MPa,钢拱架最大受力295.3 MPa,均满足规范要求。 展开更多
关键词 隧道工程 初期支护 软岩
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基于深部软岩巷道的锚注式柔性锚杆支护研究
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作者 沈国扬 李英明 叶敏杰 《煤矿机械》 2026年第1期43-47,共5页
针对深部软岩巷道围岩变形严重、支护困难的问题,引入一种新型锚注式柔性锚杆支护技术,对涡北煤矿84采区瓦斯测试巷展开修复方案设计研究,并采用数值模拟及工程应用实测的方法对修复方案可行性进行验证。模拟研究表明,以柔性锚杆与普通... 针对深部软岩巷道围岩变形严重、支护困难的问题,引入一种新型锚注式柔性锚杆支护技术,对涡北煤矿84采区瓦斯测试巷展开修复方案设计研究,并采用数值模拟及工程应用实测的方法对修复方案可行性进行验证。模拟研究表明,以柔性锚杆与普通锚杆结合的联合支护方式可产生内外拱承载效应,显著提高支护强度。最终修复方案在现场实践应用后,证实以注浆式柔性锚杆为主体的联合支护方案可以有效控制围岩变形,保证巷道稳定。 展开更多
关键词 深部软岩巷道 支护方案优化 锚注式柔性锚杆 数值模拟
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深部软岩巷道支护方案及参数优化设计
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作者 叶明才 《凿岩机械气动工具》 2026年第1期73-75,共3页
以某工程为例,设计深部软岩巷道锚杆、锚索、喷混凝土支护方案,进行支护参数优化设计,并从位移、应力分布情况及围岩破碎区范围等方面着手,分析支护效果。研究结果表明,支护参数优化后,能有效约束巷道围岩变形,改善应力分布状态,缩小围... 以某工程为例,设计深部软岩巷道锚杆、锚索、喷混凝土支护方案,进行支护参数优化设计,并从位移、应力分布情况及围岩破碎区范围等方面着手,分析支护效果。研究结果表明,支护参数优化后,能有效约束巷道围岩变形,改善应力分布状态,缩小围岩破碎区范围。 展开更多
关键词 深部软岩巷道 支护参数 围岩稳定性
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三软地层建下充填开采技术研究与应用
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作者 邹玉龙 周景奎 +1 位作者 刘明明 万蕾 《煤矿现代化》 2026年第1期80-87,共8页
梁家煤矿是典型的软岩矿井,建(构)筑物下压煤严重,为解决建下压煤开采问题,积极寻求适合软岩条件的建下充填开采方法。鉴于软岩随采随冒的特性,制约瓶颈是没有充填时间和空间,基于对煤矿安全生产先进适用技术推广目录中连采连充工艺的... 梁家煤矿是典型的软岩矿井,建(构)筑物下压煤严重,为解决建下压煤开采问题,积极寻求适合软岩条件的建下充填开采方法。鉴于软岩随采随冒的特性,制约瓶颈是没有充填时间和空间,基于对煤矿安全生产先进适用技术推广目录中连采连充工艺的不断调研、分析,结合矿井实际,系统阐述了软岩矿井实施充填开采的可行性,通过优化工作面设计、充填工艺、支护工艺、封堵工艺等,有针对性制订了软岩条件下连采连充方案。配合锚杆测力计、顶板离层仪、充填体应力计和位移计等监测方法和工具,针对充填巷双帮、单帮制定差异化支护措施,规避了顶板下沉、帮部片落的风险,经现场应用,解决了软岩顶板维护问题,开创软岩矿井充填开采的先河,填补软岩充填开采技术空白,形成一套采用固体废物实施绿色开采关键技术。 展开更多
关键词 软岩充填 随采随冒 差异化支护 连采连充
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近河道暗浜软土地基深基坑支护施工技术实践分析
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作者 潘炯 《工程建设与设计》 2026年第1期47-51,共5页
以上海某近河道暗浜软土地基深基坑工程为例,分析了在软土、暗浜等不良地质条件下的施工重难点。工程采用双排搅拌桩止水帷幕与钻孔灌注桩挡土,并结合钢筋混凝土与钢管支撑体系施工。针对暗浜区域土质松散等问题,通过提高搅拌桩水泥掺... 以上海某近河道暗浜软土地基深基坑工程为例,分析了在软土、暗浜等不良地质条件下的施工重难点。工程采用双排搅拌桩止水帷幕与钻孔灌注桩挡土,并结合钢筋混凝土与钢管支撑体系施工。针对暗浜区域土质松散等问题,通过提高搅拌桩水泥掺量、严格执行“两喷三搅”工艺及换填浅层不良土体等针对性措施,有效保障了基坑稳定与止水效果。 展开更多
关键词 深基坑工程 暗浜 支护结构 软土地基
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双地铁车站间复杂内支撑体系下的深大基坑设计
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作者 吴鑫鑫 《工程建设与设计》 2026年第3期55-58,共4页
以某市地铁某换乘区间深基坑工程为依托,基于当地地质水文条件,优化内支撑体系,提出复杂内支撑设计方案,并通过结合数值模拟及现场监测进行验证。结果表明,该体系可将围护结构最大水平位移控制在23.6 mm,邻近地铁隧道沉降量小于8 mm,满... 以某市地铁某换乘区间深基坑工程为依托,基于当地地质水文条件,优化内支撑体系,提出复杂内支撑设计方案,并通过结合数值模拟及现场监测进行验证。结果表明,该体系可将围护结构最大水平位移控制在23.6 mm,邻近地铁隧道沉降量小于8 mm,满足规范及地铁保护要求;数值模拟与现场监测数据均在合理误差以内,验证了设计的科学性与合理性。 展开更多
关键词 深大基坑 双地铁区间 复杂内支撑体系 软土地区
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软岩区域煤层沿空巷道支护方案
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作者 邢夏冰 《凿岩机械气动工具》 2026年第1期61-63,共3页
软土区域的地质特性使底板结构难以为支护结构提供有效支撑,常规支护方案存在失效、性能不佳等问题。基于此,提出软岩区域煤层沿空巷道支护方案,以5 m为间隔在巷道布置测点,用静压式比压仪测底板比压曲线,算出底板容许比压与极限底板比... 软土区域的地质特性使底板结构难以为支护结构提供有效支撑,常规支护方案存在失效、性能不佳等问题。基于此,提出软岩区域煤层沿空巷道支护方案,以5 m为间隔在巷道布置测点,用静压式比压仪测底板比压曲线,算出底板容许比压与极限底板比压,量化评估底板支撑压力。据此设计单锚索偏心支护架构,采用混凝土进行喷层封闭,形成整体性的封闭支护结构。应用结果表明,该方案下的巷道两帮累计移近量最大值为168.0 mm,平均值为110.3 mm,稳定性好,适用于软土区域。 展开更多
关键词 软岩区域 沿空巷道 支护方案
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厚煤层复杂应力条件下侵蚀巷道支护技术研究与实践
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作者 常超 《煤》 2026年第1期58-61,共4页
虎龙沟煤矿81507工作面运输巷在原有支护体系下出现了显著的围岩变形。为应对这一工程难题,本研究首先通过现场监测手段,详细记录了巷道围岩的变形数据,并深入分析了其失稳机理。在此基础上,设计了一套融合“锚杆-锚索-金属网-注浆”的... 虎龙沟煤矿81507工作面运输巷在原有支护体系下出现了显著的围岩变形。为应对这一工程难题,本研究首先通过现场监测手段,详细记录了巷道围岩的变形数据,并深入分析了其失稳机理。在此基础上,设计了一套融合“锚杆-锚索-金属网-注浆”的协同支护体系。为验证该方案的有效性,采用FLAC 3D数值模拟软件,对比分析了原支护与优化支护方案下围岩的变形响应。模拟结果证实了优化方案的可行性,随后进行了现场工业性试验。监测数据表明:实施新支护方案60 d后,围岩变形速率明显减缓并逐渐趋于稳定;90 d的观测期内,巷道顶底板累计移近量控制在190 mm以内,两帮移近量为134 mm,底鼓量为93 mm.上述结果证明,该联合支护技术能够有效维持复杂应力条件下巷道的长期稳定。 展开更多
关键词 深部开采 软岩巷道 失稳机制 联合支护技术
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深部高应力软岩巷道钢管混凝土支架支护技术
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作者 李亚其 《江西煤炭科技》 2026年第1期117-120,共4页
针对胡底煤业二盘区大巷围岩失稳破坏、控制困难等诸多问题,通过分析大巷破坏原因,并依托巷道承压环强化支护理论,决定采用“锚网喷+钢管混凝土支架”联合支护方式;应用表明,该联合支护承载能力强,能有效抑制巷道变形,巷道满足现场使用... 针对胡底煤业二盘区大巷围岩失稳破坏、控制困难等诸多问题,通过分析大巷破坏原因,并依托巷道承压环强化支护理论,决定采用“锚网喷+钢管混凝土支架”联合支护方式;应用表明,该联合支护承载能力强,能有效抑制巷道变形,巷道满足现场使用需求。 展开更多
关键词 巷道 高应力 软岩 钢管混凝土支架 联合支护
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Study on Repairing Permanent Transportation Roadway in Deep Mining by Bolt-Shotcrete and Mesh Supporting 被引量:10
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作者 宋宏伟 鹿守敏 《International Journal of Mining Science and Technology》 SCIE EI 1999年第2期167-171,共5页
The roadway support in many places of Jiulongkou Colliery, Fengfeng Mining Bureau, such as in the Permanent transportation roadway, was failed or locally caved, which seriously affected the colliery’s coal production... The roadway support in many places of Jiulongkou Colliery, Fengfeng Mining Bureau, such as in the Permanent transportation roadway, was failed or locally caved, which seriously affected the colliery’s coal production performance and safety. Based on analysis of supporting objects for roadway repairing, this paper proposes the supporting parameters and condruction technics. The industrial ted of 70m long roadway repairing shows that the proposed parameters and technics of bolt shotcrete and mesh support for roadway repairing are reasouable, bring good technical and economic results for the colliery, and the repairing is successful. 展开更多
关键词 ROADWAY repairing soft ROCK support bolt-shotcrete supportING broken ROCK zone
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