scholarly journals Influencing Factors of Disturbance Effects of Blasting and Driving of Deep Mine Roadway Groups

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Jiaguang Kan ◽  
Peng Wang ◽  
Peng Wang
Keyword(s):  
Conveyor Belt ◽  
Horizontal Distance ◽  
Deep Mine ◽  
Disturbance Effects ◽  
Rock Structure ◽  
Blasting Excavation ◽  
Mine Roadway ◽  
Deformation Speed ◽  
Group Layout ◽  
Bolt Support

The development and application of roadway group layout methods in coal mines have become more common and the mutual disturbance of blasting and driving of roadway groups has also become more prominent at depth. To improve the stability of rock mass surrounding roadways, we performed a systematic study on the factors that influence blasting and driving disturbances of adjacent roadways in deep mine roadway groups. We use the dynamic analysis module in FLAC3D to obtain the influence laws of three factors on the disturbance effects of adjacent roadways, namely, excavation methods, layer position changes of the roadway group, and whether or not bolt support is applied in the first roadway. Blasting strongly influences the surrounding roadway and increased horizontal distance can effectively reduce the disturbance effects of blasting and driving between adjacent roadways compared with increased vertical distance. Bolt support of the first excavated roadway enhances the roadway integrity and better stabilizes the rock structure surrounding the roadway. Industrial tests were carried out on three uphill roadways in the Gubei no. 1 mine (6-2). The monitoring results show that the movement of the roof and floor of the floor uphill return wind roadway is larger than that on the two sides. There is no notable change in the deformation speed of the surrounding rock in the floor return air roadway, but the deformation speed of the uphill conveyor belt roadway changes significantly. The results show that when the blasting excavation of a deep mine roadway group is more than five times the tunnel spacing, the increased horizontal distance effectively reduces the disturbance effects of excavation between adjacent roadways, which is consistent with the simulation results.

scholarly journals The Effectiveness of Bolt Support in Maintaining Mine Roadway

1982 ◽  
Vol 98 (1128) ◽  
pp. 73-77
Author(s):  
Makoto IHARA ◽  
Kikuo MATSUI ◽  
Yukiyoshi ICHIKAWA
Keyword(s):  
Mine Roadway ◽  
Bolt Support

scholarly journals Hollow Effect of Ground Vibration Induced by Electronic Detonator in Shallow Tunnel

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Weijie Ding ◽  
Bei Jia ◽  
Dianshu Liu
Keyword(s):  
Field Experiments ◽  
Optimal Parameter ◽  
Ground Vibration ◽  
Dominant Frequency ◽  
Tunnel Construction ◽  
Shallow Tunnel ◽  
Horizontal Distance ◽  
Mode Decomposition ◽  
Blasting Excavation ◽  
Electronic Detonator

Blasting excavation is extensively used in tunnel construction, and the adverse effect of ground vibration induced by blasting on surrounding structures and inhabitants is a critical problem. This study aims to investigate the tunnel hollow effect on triaxial peak particle velocities (PPV) and dominant frequencies induced by electronic detonator. Field experiments were conducted in a shallow tunnel construction site and the ground vibration waveforms were recorded. Variational mode decomposition (VMD) was applied to denoise and correct the zero-drift phenomenon, and the proposed method of selecting the optimal parameter was verified. A series of statistical analyses and tests were performed to evaluate the differences of peak particle velocity and dominant frequency among various monitoring points. The results showed that the hollow effect on Z-axis PPV is significant, and triaxial PPV is also affected when the horizontal distance exceeds 30 m. The hollow effect on dominant frequency could not be identified since the hollow of tunnel is a free face, and the dominant frequency of reflected wave remains unchanged. An augmented factor of 1.229 is determined carefully as the hollow effect factor on PPV. Therefore, blasting vibration induced by electronic detonator of the excavated zone should be attached with greater importance, and hollow effect on PPV should be considered in the blasting design of tunnel excavation.

The Application of Thermal Insulation Glazed Hollow Bead Concrete in Tunnel Cooling Structure

2012 ◽  
Vol 226-228 ◽  
pp. 1699-1703 ◽  
Author(s):  
Ke Jie Li ◽  
Zhu Li ◽  
Xiu Hua Guo ◽  
Yuan Zhen Liu
Keyword(s):  
Thermal Insulation ◽  
Effect Of Temperature ◽  
Insulation Material ◽  
Tunnel Wall ◽  
Mixture Ratio ◽  
Deep Mine ◽  
Mining Depth ◽  
Exhaust Heat ◽  
Mine Roadway ◽  
Coefficient Of Heat Conductivity

With the mining depth increasing, the effect of temperature on coal mine is outstanding with each passing day. In order to enhance the tunnel insulating layer heat insulation effect, thermal insulation glazed hollow bead concrete will be used in tunnel wall thermal insulation layer, the characteristics of thermal insulation glazed hollow bead concrete will be discussed and the appropriate mixture ratio and coefficient of heat conductivity will also be determined, as well as in the basis of reasonable theoretical analysis and derivation, prediction of the thermal insulation material of surrounding rock after exhaust heat will drop significantly, and it is proved that the thermal insulation glazed hollow bead concrete used in deep mine roadway can produce the benefit and have broad prospects.

scholarly journals Numerical Simulation Study on the Influence of Mine Earthquake on the Bolt Stress

2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Xiaoqian Zhang ◽  
Heng Zhang ◽  
Chengmin Wei
Keyword(s):  
Safety Factor ◽  
Coal Mine ◽  
Axial Stress ◽  
Microseismic Monitoring ◽  
Earthquake Hypocenter ◽  
Mine Roadway ◽  
Bolt Stress ◽  
The Stability ◽  
The Impact ◽  
Bolt Support

Mine earthquake, as an underground disaster that occurs frequently, has a great impact on coal mine roadway and support. The stability analysis of the bolt support in roadway under different mine earthquake magnitudes is a key issue to be solved urgently in mining fields. This paper attempted to simulate the occurrence state of mine earthquake with explosive blasting process and verified it with actual coal mine microseismic monitoring data. ANSYS/LSDYNA software was used to analyze the impact of magnitude and location of mine earthquake hypocenter on the stability of bolt support and the dynamic stress characteristics of bolt. The results showed that with the increase in source energy of mine earthquake, the damage location of bolt mainly appears in the front of bolt and the loading position has no obvious change, but there is stress wave superposition effect, which deepens the damage of bolt. The bolts in the middle of the lane and the middle of the roof are greatly affected, so the support strength should be strengthened in these places. In addition, this paper compared the safety factor of bolt and the supporting effect of different schemes from three aspects such as roof subsidence, axial stress of bolt, and safety factor of bolt and then put forward a more economical and effective supporting scheme.

Sign in / Sign up

Export Citation Format

Share Document