scholarly journals The Stability of Roadway Groups under Rheology Coupling Mining Disturbance

2021 ◽  
Vol 13 (21) ◽  
pp. 12300
Author(s):  
Sen Yang ◽  
Guichen Li ◽  
Ruiyang Bi ◽  
Bicheng Yao ◽  
Ruiguang Feng ◽  
...  
Keyword(s):  
Coupling Effect ◽  
Coal Pillar ◽  
Mine Safety ◽  
Key Strata ◽  
Deep Well ◽  
Working Face ◽  
Safety Production ◽  
Mining Disturbance ◽  
The Stability ◽  
And Control

The deep roadway groups play an important role in transportation and ventilation in coal mine production. Therefore, it is very important to comprehensively analyze the coupling effect of rheological deformation and coal mining on the stability of the roadway groups. In this paper, the disturbance effects of different stop-mining lines on roadway groups under long-term rheology were investigated by numerical simulation, and the failure mechanism of roadway groups with large sections and multiple disturbances in a deep well was revealed. The results show that the long working face will lead to the collapse of key strata, and the influence range will spread to the adjacent roadway groups. When the distance between the working face and the stop-mining line is 100 m, the roadway groups cannot be affected by the working face mining, and the reserved width of the coal pillar can be determined to be 100 m, which increases the stability of the roadway’s surrounding rock and maintains the mine safety production. This paper aims to provide a reference for groups design and control under similar conditions.

scholarly journals Stability Analysis of Roadway Groups under Multi-Mining Disturbances

2021 ◽  
Vol 11 (17) ◽  
pp. 7953
Author(s):  
Yuantian Sun ◽  
Ruiyang Bi ◽  
Qingliang Chang ◽  
Reza Taherdangkoo ◽  
Junfei Zhang ◽  
...  
Keyword(s):  
Coal Mining ◽  
Coal Pillar ◽  
Stability Control ◽  
Surrounding Rock ◽  
Key Strata ◽  
Working Face ◽  
Roadway Stability ◽  
Mining Disturbance ◽  
Mining Face ◽  
The Stability

The roadway stability has been regarded as the main challenging issue for safety and productivity of deep underground coal mines, particularly where roadways are affected by coal mining activities. This study investigates the −740 m main roadway in the Jining No. 2 Coal Mine to provide a theoretical basis for the stability control of the main deep roadway affected by disturbances of adjacent working activities. Field surveys, theoretical analyses, and numerical simulations are used to reveal mechanisms of the coal mining disturbance. The field survey shows that the deformation of roadway increases when the work face advances near the roadway group. Long working face mining causes the key strata to collapse based on the key strata theory and then disturbs the adjacent roadway group. When the working face is 100 m away from the stop-mining line, the roadway group is affected by the mining face, and the width roadway protection coal pillar is determined to be about 100 m. Flac3D simulations prove the accuracy of the theoretical result. Through reinforcement and support measures for the main roadway, the overall strength of the surrounding rock is enhanced, the stability of the surrounding rock of the roadway is guaranteed, and the safe production of the mine is maintained.

Numerical Analysis for the Influence of Mining Deep Coal Seam on Oversize Normal Fault

2014 ◽  
Vol 1073-1076 ◽  
pp. 2112-2116
Author(s):  
Xin Xian Zhai ◽  
Shi Wei Zhang ◽  
She Jun Ma ◽  
Guang Sen Li
Keyword(s):  
Coal Seam ◽  
Abutment Pressure ◽  
Water Inrush ◽  
Coal Pillar ◽  
Normal Fault ◽  
Mine Safety ◽  
Coal Face ◽  
Safety Production ◽  
Floor Water Inrush ◽  
The Stability

The F2 fault Guo in Tianyu Coal Mine belongs to the oversize normal fault, and mining deep coal seam has an influence on the floor water-inrush. Therefore, study the reasonable width of the fault protected coal pillar is a great significance for the mine safety production. With different advance distances of coal face into the fault hangingwall, the authors, by FLAC numerical calculation, studied the characteristics of plastic zone and stress field in front of the coal face. The results show that influence zone scope of moving abutment pressure is about 70~ 80m. The fault is still in the pressure-relief area when it is in the moving abutment pressure zone. The conclusion is conducive to the stability of F2 fault Guo, to prevent the floor from water-inrush, when the reasonable coal pillar width of the fault is wider than 80m.

scholarly journals Stability Control of a Goaf-Side Roadway under the Mining Disturbance of an Adjacent Coal Working Face in an Underground Mine

2019 ◽  
Vol 11 (22) ◽  
pp. 6398
Author(s):  
Houqiang Yang ◽  
Changliang Han ◽  
Nong Zhang ◽  
Changlun Sun ◽  
Dongjiang Pan ◽  
...  
Keyword(s):  
Stress Distribution ◽  
Stability Control ◽  
Surrounding Rock ◽  
Engineering Practice ◽  
Key Strata ◽  
Coal Recovery ◽  
Working Face ◽  
Underground Coal Mines ◽  
Mining Disturbance ◽  
The Stability

Goaf-side roadway driving could not only notably reduce the loss of coal resources and improve the coal recovery rates, but also greatly mitigate the imbalance between excavation speed and production needs, which are able to prolong the service life of the mine and are pivotal to sustainable and efficient development of underground coal mines. However, it is difficult to control the stability of the goaf-side roadway, especially under mining disturbance of another adjacent coal working face. In order to control the stability of the goaf-side roadway, Haulageway 1513 in the Xinyi Coal Mine of China, under mining disturbance, theoretical analysis, numerical simulation, and engineering practice were carried out to reveal the mechanism of overburden key strata fracture, stress distribution, and deformation characteristics of the surrounding rock of the goaf-side roadway due to mining disturbance. Results showed that some key strata above Goaf 1512 did not fracture due to the influence of the strata caving angles. However, these key strata would fracture and break into rock blocks when suffering from mining disturbance of the adjacent coal working face, which changed the stress distribution and increased the deformations of the surrounding rock of the goaf-side roadway. The combined techniques of pressure relief and bolt support were proposed and carried out to control the stability of the goaf-side roadway. Engineering practice indicated that the maximum deformations of the roof and sidewall-to-sidewall were 220 mm and 470 mm, respectively. The deformations of the goaf-side roadway under mining disturbance were efficiently controlled.

scholarly journals Study on Reasonable Roadway Position of Working Face under Strip Coal Pillar in Rock Burst Mine

2020 ◽  
Vol 2020 ◽  
pp. 1-21 ◽  
Author(s):  
Hengze Yang ◽  
Zhongping Guo ◽  
Daozhi Chen ◽  
Chao Wang ◽  
Fuyu Zhang ◽  
...  
Keyword(s):  
Simulation Experiment ◽  
Longitudinal Crack ◽  
Coal Pillar ◽  
Distribution Law ◽  
Working Face ◽  
Coal Wall ◽  
Safety Production ◽  
The Stability ◽  
Two Sides ◽  
Selection Of

It is of great significance to study the reasonable position of mining roadway under strip coal pillar for increasing the stability of mining roadway, reducing the waste of resources, and realizing the safety production of working face. Based on the research background of the working face under the strip coal pillar in Jinqiao Coal Mine of Jining, Shandong Province, through theoretical analysis, similar material simulation experiment, and numerical simulation experiment, the stress distribution law, plastic failure range, and rationality of coal pillar setting in different width sections are systematically studied. Finally, the tailentry of working face is determined at the position of 5 m from the bottom of strip coal pillar to 1308 goaf. During the mining period of 1310 working face, the peak value of side abutment pressure is at the position of 3∼4 m; beyond 25 m in front of the coal wall, the deformation of the surrounding rock on the tailentry surface is small. After entering the advanced support section, the deformation of the two sides is mainly longitudinal crack expansion and local shallow small flakes; however, the roof is complete and stable. Therefore, the selection of tailentry location and coal pillar width has played a good role. The research results of this study can provide some reference for similar mine with similar geological and production technical conditions.

scholarly journals Study on the Fracture Law of Inclined Hard Roof and Surrounding Rock Control of Mining Roadway in Longwall Mining Face

Energies ◽  
2020 ◽  
Vol 13 (20) ◽  
pp. 5344
Author(s):  
Feng Cui ◽  
Shuai Dong ◽  
Xingping Lai ◽  
Jianqiang Chen ◽  
Chong Jia ◽  
...  
Keyword(s):  
Energy Release ◽  
Longwall Mining ◽  
Coal Pillar ◽  
High Energy ◽  
Mechanical Analysis ◽  
Engineering Practice ◽  
Analysis Model ◽  
Hard Roof ◽  
Working Face ◽  
The Stability

In the inclination direction, the fracture law of a longwall face roof is very important for roadway control. Based on the W1123 working face mining of Kuangou coal mine, the roof structure, stress and energy characteristics of W1123 were studied by using mechanical analysis, model testing and engineering practice. The results show that when the width of W1123 is less than 162 m, the roof forms a rock beam structure in the inclined direction, the floor pressure is lower, the energy and frequency of microseismic (MS) events are at a low level, and the stability of the section coal pillar is better. When the width of W1123 increases to 172 m, the roof breaks along the inclined direction, forming a double-hinged structure, the floor pressure is increased, and the frequency and energy of MS events also increases. The roof gathers elastic energy release, and combined with the MS energy release speed it can be considered that the stability of the section coal pillar is better. As the width of W1123 increases to 184 m, the roof in the inclined direction breaks again, forming a multi-hinged stress arch structure, and the floor pressure increases again. MS high-energy events occur frequently, and are not conducive to the stability of the section coal pillar. Finally, through engineering practice we verified the stability of the section coal pillar when the width of W1123 was 172 m, which provides a basis for determining the width of the working face and section coal pillar under similar conditions.

scholarly journals Dual Quaternion Based Close Proximity Operation for In-Orbit Assembly via Model Predictive Control

2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Chuqi Sun ◽  
Yan Xiao ◽  
Zhaowei Sun ◽  
Dong Ye
Keyword(s):  
Control System ◽  
Model Predictive Control ◽  
Predictive Control ◽  
Coupling Effect ◽  
Suboptimal Control ◽  
Dual Quaternion ◽  
Close Proximity ◽  
The Stability ◽  
Six Degree Of Freedom ◽  
And Control

This paper studies the problem of guidance and control for autonomous in-orbit assembly. A six-degree-of-freedom (6-DOF) motion control for in-orbit assembly close proximity operation between a service satellite and a target satellite is addressed in detail. The dynamics based on dual quaternion are introduced to dispose the coupling effect between translation and rotation in a succinct frame, in which relevant perturbation and disturbance are involved. With the consideration of economical principle for fuel consume, a generic control system based on model predictive control (MPC) is then designed to generate a suboptimal control sequence for rendezvous trajectory considering actuator output saturation. The stability and robustness issues of the MPC-based control system are analyzed and proved. Numerical simulations are presented to demonstrate the effectiveness and robustness of the proposed control scheme, while additional comparisons for diverse horizons of the MPC are further conducted.

scholarly journals Research on Management and Control of Miners’ Unsafe Behavior Based on Gray Theory

2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Shuicheng Tian ◽  
Guangtong Shao ◽  
Hongxia Li ◽  
Pengfei Yang ◽  
Qingxin Dang ◽  
...  
Keyword(s):  
Coal Mine ◽  
Mine Safety ◽  
Gray Relational Analysis ◽  
Safety Level ◽  
Labor Discipline ◽  
Production Water ◽  
Unsafe Behavior ◽  
Safety Production ◽  
Unsafe Behaviors ◽  
And Control

A large number of accidents and scientific researches show that miners’ unsafe behavior affects coal mine safety production seriously. In order to effectively reduce the incidence of miners’ unsafe behavior, to improve their safety level, and reduce accidents caused by it, this paper used gray relational analysis method to analyze the miners’ unsafe behavior of W mine and quantitatively calculated the risk value of miners’ unsafe behavior. The results showed that the risk value of unsafe behavior in violation of labor discipline was 0.4358, which was much higher than that of other miners’ unsafe behaviors. Therefore, unsafe behavior in violation of labor discipline was determined as the key point of control in the next stage. Then, GM (1, 1) method was used to establish a predicted model for unsafe behavior, to predict the number of unsafe behaviors in violating labor discipline in next quarter, and to determine reasonable unsafe behavior control target. This study plays a driving role in controlling unsafe behaviors of miners and improving safe production water of coal mine.

scholarly journals Analysis of regenerated roof and instability support control countermeasures in a steeply dipping working face

2019 ◽  
Vol 38 (4) ◽  
pp. 1082-1098 ◽  
Author(s):  
Xiaolou Chi ◽  
Ke Yang ◽  
Qiang Fu
Keyword(s):  
Physical Simulation ◽  
Middle Part ◽  
Metal Mesh ◽  
Roof Structure ◽  
Working Face ◽  
Roof Fall ◽  
Set Up ◽  
The Stability ◽  
And Control ◽  
Compaction Degree

Roof regeneration in coal mining occurs when the remaining bottom slice of thick coal is re-mined. In view of the challenges of roof fall and instability support of a regenerative roof in the mining of steeply dipping coal seams, combined with the geological and engineering conditions of the working face in the Panbei Coal Mine, the mechanism of the instability of the regenerative roof and support is studied, and control countermeasures are proposed. Based on the comprehensive combination of the measurement of the roof structure, physical simulation, numerical simulation, and theoretical analysis, the cementation and compaction degree of the regenerated roof were described. The caving and sliding law of the regenerated roof after bottom slice mining was explored, and the model of support dumping and sliding instability under the roof fall state was established. The results obtained yielded three main findings. Firstly, the compaction degree of the regenerative roof is higher than that of the middle part of the working face, and the compaction degree of the upper part of the working face is the smallest. Secondly, the overburden structure instability of the bottom slice underwent six stages. The fracture of the cantilever beam and the slippage of gangue are the reasons for the enhancement of the acoustic signal at each stage. Finally, the upper part of the stope was identified as the crucial zone in the prevention and control of the support instability. A moving method of metal mesh with pressure and roof scraping was developed, and the support anti-overturning and anti-skid jack was set up to effectively control the stability of the support and roof fall, for safe and efficient mining of a steeply dipping coal seam under a regenerative roof.

The Comprehensive Water Control Technology in the Coal Floor Limestone High Confined Aquifer

2012 ◽  
Vol 518-523 ◽  
pp. 4283-4287 ◽  
Author(s):  
Pu Shan Li ◽  
Li Li A ◽  
Xin Yi Wang
Keyword(s):  
Water Inrush ◽  
Mine Safety ◽  
Confined Aquifer ◽  
Water Control ◽  
Control Plan ◽  
Fracture Development ◽  
Safety Production ◽  
Aquifer Characteristics ◽  
And Control ◽  
Coefficient Method

To solve water disasters of coal seam bottom in the 8th coal mine, with the analysis on the bottom aquifer characteristics, the water inrush coefficient method was applied to evaluate the dangers of the aquifer floor and to the dangers division of water inrush. In combination with the karst fracture development conditions of the aquifer, we designed the water prevention and control plan of the limestone water under the seam floor. All the schemes set the basis for the mine safety production.

scholarly journals Study on Failure Law of Mining Process of Narrow Coal Pillars in Fully Mechanized Caving Roadway

2019 ◽  
Vol 136 ◽  
pp. 04001
Author(s):  
Haifeng Ren ◽  
Xuewen Zhao ◽  
Peng Cao
Keyword(s):  
Finite Difference ◽  
Coal Pillar ◽  
Distribution Characteristics ◽  
Test Results ◽  
Anchor Cable ◽  
Working Face ◽  
Safety Production ◽  
Damage Law ◽  
Simulation Results ◽  
Coal Pillars

In order to determine the damage law of narrow coal pillars in the roadway along the goaf, taking the 4-5(06) working face of a mine in Xinjiang as the research object, the 3D finite difference software FLAC3D is used to analyse the stress and displacement distribution characteristics of narrow coal pillars in the mining process. The results show that the internal stress of the coal pillar reaches the peak when the narrow coal pillar advances from 11m to 12m, and the coal pillar is subjected to the pre-supporting pressure, the range of the rupture zone is increased, and the bearing capacity is obviously reduced. When the working face advances 65m, the displacement in the coal column reaches a peak, and the deformation of the coal column is more serious. The field test results show that the damage law of the narrow coal pillars in the working face mining process is basically consistent with the simulation results. After the bolts, the cable-stayed anchor cable and the shotcrete, the deformation of the narrow coal pillar is in a controllable range, and the safety production requirements of the working face are realized.

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