The Surrounding Rock of Deep Borehole Pressure Relief and Let the Pressure Bolt Coupling Analysis

2013 ◽  
Vol 446-447 ◽  
pp. 1421-1424 ◽  
Author(s):  
Shu Guang Zhang ◽  
Long Chen ◽  
Hong Yu Jia

Roadway borehole pressure relief and let the pressure anchor combined support technology were based on using the new pressure high strength bolt instead of ordinary bolt ,Combined with the borehole pressure relief principle, aim at releasing high stress of surrounding rock of roadway ,Complying with the deformation characteristics of supporting technology of the surrounding rock. In this paper, we used scaled numerical simulation technology —— ADINA to analyze the roadway borehole pressure relief and let the pressure anchor coupling support technology. To the tunnel, we used the method of numerical simulation of let the pressure bolt support independently, drilling pressure relief, and borehole pressure relief and let the pressure anchor coupling support three kinds of the comparison numerical simulation. The advantages of coupling supporting effect was elaborated, It was instructive for the deeply roadway engineering in the future.

2020 ◽  
Vol 2020 ◽  
pp. 1-14
Author(s):  
Xiaojie Yang ◽  
Chenkang Liu ◽  
Honglei Sun ◽  
Songlin Yue ◽  
Yuguo Ji ◽  
...  

Affected by the mining activities of the working face, the surrounding rock of the roadway is easily deformed and destroyed. For deep buried roadways, the deformation and destruction of the surrounding rock is particularly prominent. Under the influence of in situ stress fluctuation, 3−1103 tailgate of the Hongqinghe coal mine was in a complex stress environment with a maximum stress exceeding 20 MPa. Affected by mining stress, the roadway behind the working face was seriously deformed. In order to alleviate the deformation of the roadway, directional blasting and cutting measures for the 3−1103 tailgate were adopted in this paper. The mechanism of crack propagation in single-row to three-hole directional blasting was revealed by numerical simulation. The blasted rock was divided into three regions according to the crack condition. The numerical analysis of the cutting heights of 0 m, 10 m, 12 m, and 14 m, respectively, showed the stress peaks of different cutting heights and the deformation law of the surrounding rock. The pressure relief effect was the best at 14 m cutting height. At this time, the peak stress was 39 MPa with the smallest roadway deformation. Based on numerical simulation and theoretical analysis results, engineering tests were carried out. Field monitoring showed that the deformation of the roadway was inversely proportional to the roof cutting height. The higher the cutting height is, the more preferential the roadway is to reach the stable state. It can be concluded that directional blasting can change the surrounding rock structure, control the deformation of the roadway, and play a role in pressure relief. It provides a new measure to control roadway deformation.


2016 ◽  
Vol 23 (2) ◽  
pp. 440-448 ◽  
Author(s):  
Shu-cai Li ◽  
Hong-tao Wang ◽  
Qi Wang ◽  
Bei Jiang ◽  
Fu-qi Wang ◽  
...  

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Wen Zhai ◽  
Yachao Guo ◽  
Xiaochuan Ma ◽  
Nailv Li ◽  
Peng Zhang ◽  
...  

With the increase of mining depth in underground engineering, deep ground pressure has an extremely unfavorable impact on safety production and the economic benefits of coal mines and the control of the roadway stability in deep mines are gradually highlighted. In this study, the working face 14203 of the Zaoquan coal mine was taken as the engineering background, the deformation mechanism of surrounding rock in the deep-buried high-stress roadway was analyzed, and the hydraulic fracturing pressure relief technology in the advanced roadway was proposed for surrounding rock control. Finally, the numerical simulation and field tests were used to validate the comprehensive effect of the proposed technology. Without damaging the roadway stability in the working face, the hydraulic fracturing pressure relief technology can optimize the stress environment and stability of the roadway through the artificial control of the roof fracture position. The numerical simulation shows that under the action of hydraulic fracturing, the cutting slot is formed, the deformation and failure mode of the roof are changed, the stress of surrounding rock is reduced, and the development of the plastic zone of surrounding rock is limited. As a result, the stability of surrounding rock in the roadway is effectively protected. The field test shows that after the adoption of hydraulic fracturing pressure relief technology, the roof subsidence, floor separation, bolt stress, and cable stress decrease, and the deformation of surrounding rock is reduced significantly. Therefore, hydraulic fracturing pressure relief technology is verified as an effective method to control the large deformation of the surrounding rock in the deep-buried roadway.


2012 ◽  
Vol 466-467 ◽  
pp. 1031-1035
Author(s):  
Zhan Jin Li ◽  
Xue Li Zhao ◽  
Yang Zhang

Using numerical simulation technology, coupling support mechanism of anchor-mesh-cable+ bottom-anchor has been analyzed. According to actual engineering of the Fifth Coal Mine of Hemei, the reasonable coupling support structure of anchor-mesh-cable+ bottom-anchor + truss under high stress has been analyzed. It is proposed roadway damage is twist deformation under high stress. By using the reasonable coupling support structure and parameter of anchor-mesh-cable+ bottom-anchor the high stress in underground rock laneway can be controlled and supporting effect is perfect.


2021 ◽  
Vol 13 (8) ◽  
pp. 4412
Author(s):  
Houqiang Yang ◽  
Nong Zhang ◽  
Changliang Han ◽  
Changlun Sun ◽  
Guanghui Song ◽  
...  

High-efficiency maintenance and control of the deep coal roadway surrounding rock stability is a reliable guarantee for sustainable development of a coal mine. However, it is difficult to control the stability of a roadway that locates near a roadway with large deformation. With return air roadway 21201 (RAR 21201) in Hulusu coal mine as the research background, in situ investigation, theoretical analysis, numerical simulation, and engineering practice were carried out to study pressure relief effect on the surrounding rock after the severe deformation of the roadway. Besides, the feasibility of excavating a new roadway near this damaged one by means of pressure relief effect is also discussed. Results showed that after the strong mining roadway suffered huge loose deformation, the space inside shrank so violently that surrounding rock released high stress to a large extent, which formed certain pressure relief effect on the rock. Through excavating a new roadway near this deformed one, the new roadway could obtain a relative low stress environment with the help of the pressure relief effect, which is beneficial for maintenance and control of itself. Equal row spacing double-bearing ring support technology is proposed and carried out. Engineering practice indicates that the new excavated roadway escaped from possible separation fracture in the roof anchoring range, and the surrounding rock deformation of the new roadway is well controlled, which verifies the pressure relief effect mentioned. This paper provides a reference for scientific mining under the condition of deep buried and high stress mining in western China.


2011 ◽  
Vol 71-78 ◽  
pp. 3572-3576
Author(s):  
An Nan Jiang ◽  
Peng Li

The uniform zonal disintegration of surrounding rock is the peculiar phenomena of deep and high stress field, researching the inner mechanism and affecting factors has important meaning for guaranteeing the safety of deep engineering. The paper adopted strain soft Mohr-Coulomb model and carried out numerical simulation of surrounding rock fracture and excavation. The simulation states that along with the unloading time accumulation, the shear belt produced from tunnel wall and developed to inner rock. The corresponding shear stress concentration zone also spread to inner rock and destroy zone increasing. The pore water pressure increasing will accelerate the shear belt developing and increase the destroy degree.


2019 ◽  
Vol 2019 ◽  
pp. 1-15 ◽  
Author(s):  
Enze Zhen ◽  
Yubing Gao ◽  
Yajun Wang ◽  
Siming Wang

Gob-side entry retaining is an environmentally friendly nonpillar mining technology with high efficiency and safety. With the continuous exploration of the gob-side entry retained by filling (GERF) with roadside supports, the GERF has enabled nonpillar mining. However, dense roadside supports or filled artificial pillars become subject to the pressure of roof pressure instead of coal pillars, which causes problems. Recently, an original innovative gob-side entry retaining technology by roof cutting and pressure relief (RCPR) was developed and extensively implemented in China’s coal production. The gob-side entry formed by different retaining methods has exhibited some differences in the strata behaviors and the results of retained roadways. Via industrial case and numerical simulation, this study explored the influence of entry retaining methods on the results of the entry retained. The results indicate that the total deformation of the surrounding rock of the GERF is larger and more severe; the convergence between the roof and floor and the entry sides displacement is 885 mm and 216 mm, respectively; the hydraulic support pressure near the retained entry is larger; and the peak value is 38.7 MPa. The deformation of the surrounding rock by RCPR is relatively small; the convergence between the roof and the floor and the entry sides displacement is 351 mm and 166 mm, respectively; the hydraulic support pressure near the retained entry is weakened to a certain extent; the peak value is 32.2 MPa; and the peak pressure is reduced by 16.8% compared with the GERF. A numerical simulation analysis reveals the following findings: RCPR changes the surrounding rock structure of a gob-side entry, optimizes the surrounding rock stress environment, and belongs to active pressure-relief entry retaining; the GERF does not adjust the surrounding rock structure of a gob-side entry and belongs to passive pressure-resistance entry retaining; and the surrounding rock of a gob-side entry is significantly affected by pressure. These two methods of gob-side entry retaining have different effects on the surrounding rock of the entry retained. This study can contribute to an exploration of the strata behaviors and the results of a retained roadway by the GERF or RCPR method.


2012 ◽  
Vol 446-449 ◽  
pp. 1657-1660
Author(s):  
Wei Dong Lv ◽  
Nan Nan Zhao

For roadway driving along next goaf of strip pillar second mining, being influenced by the abutment pressure of previous coal mining face and main roof breaking rotary deformation, the surrounding rock deformation is serious and the control effect of ordinary bolt supporting on the general stability of roadway driving along next goaf is poorer. According to the concrete geological and technique condition of the 2351 second mining strip pillar in Daizhuang Colliery, adopting the united support pattern combined high strength bolt of levorotatory continuous thread and anchor of low relaxation prestress, the safety of the roadway can be ensured and the stability of the roadway surrounding rocks can be improved. It is of significant reference meaning for bolting support of roadway driving along next goaf of second mining strip pillar under similar condition.


Sign in / Sign up

Export Citation Format

Share Document