Research on Loose Circle Test of Deep Broken Roadway

2014 ◽  
Vol 638-640 ◽  
pp. 904-907 ◽  
Author(s):  
Feng Zhan Cui ◽  
Hua Jun Xue ◽  
Tian Yu He ◽  
Tao Tao Li ◽  
Jin Jing Zuo ◽  
...  
Keyword(s):  
Soft Rock ◽  
Surrounding Rock ◽  
Sonic Method ◽  
Single Hole ◽  
Deep Well ◽  
The Stability ◽  
Two Sides

To control the stability of deep well broken surrounding rock, single-hole sonic method is used to test the loose circle of-1180 east-rock main roadway and its damage range. The study indicates the loose circle is about 1.8 ~ 2.2 m, which is typical large loose circle. And its button is slightly larger than two sides’, right side slightly larger than left. The roadway rock has some engineering features of soft rock. The broken and expand deformation of loose circle does large, difficult to support. Combined support is usually used in this rock condition.

Judgement Method for Surrounding Rock Stability of Guanjiao Tunnel Based on Catastrophe Theory

2011 ◽  
Vol 90-93 ◽  
pp. 2307-2312 ◽  
Author(s):  
Wen Jiang Li ◽  
Su Min Zhang ◽  
Xian Min Han
Keyword(s):  
Plastic Strain ◽  
Catastrophe Theory ◽  
Soft Rock ◽  
Surrounding Rock ◽  
In Situ Monitoring ◽  
Engineering Practice ◽  
Stability Of Surrounding Rock ◽  
The Stability ◽  
Rock Tunnel

The stability judgement of surrounding rock is one of the key jobs in tunnel engineering. Taking the Erlongdong fault bundle section of Guanjiao Tunnel as the background, the stability of surrounding rock during construction of soft rock tunnel was discussed preliminarily. Based on plastic strain catastrophe theory, and combining numerical results and in-situ data, the limit displacements for stability of surrounding rock were analyzed and obtained corresponding to the in-situ monitoring technology. It shows that the limit displacements obtained corresponds to engineering practice primarily. The plastic strain catastrophe theory under unloading condition provides new thought for ground stability of deep soft rock tunnel and can be good guidance and valuable reference to construction decision making and deformation managing of similar tunnels.

Study on the Application of Bolt-Grout Reinforcement in the Deep Soft Rock Roadway

2011 ◽  
Vol 90-93 ◽  
pp. 1956-1959 ◽  
Author(s):  
Zhi Lin Dun ◽  
Da Shuai Ren ◽  
Lian Wei Ren
Keyword(s):  
Soft Rock ◽  
Field Monitoring ◽  
Surrounding Rock ◽  
Geological Condition ◽  
Mining Depth ◽  
Air Inlet ◽  
Strata Behavior ◽  
Soft Rock Roadway ◽  
Two Sides ◽  
Rock Roadway

With the increasement of mining depth, the strata behavior of the roadway is obvious. As the stress of surrounding rock increases, the bottom of the soft rock roadway becomes deformed easily compressed by its top rock and two sides rock, which leads to the occurrence of the pucking and roadway destruction. Aiming the air inlet roadway destruction phenomenon of -450th level powder magazine in Hebi Zhongtai Mining Co.Ltd, the geological condition and the mechanism of the roadway failure are analysed comprehensively, and the bolt-grout supporting method is also proposed in this paper. At last, the deformation and heaving floor are controlled effectively which is proved by the field monitoring results.

Numerical Simulation of Bolt-Mesh-Anchor Support Technology at Soft Rock Roadway

2013 ◽  
Vol 868 ◽  
pp. 251-254 ◽  
Author(s):  
Hui Yu ◽  
Ling Gen Kong ◽  
Zhi Yong Niu ◽  
Shi Ting Zhu ◽  
Dan Yang Jing
Keyword(s):  
Simulation Analysis ◽  
Soft Rock ◽  
Confining Pressure ◽  
Surrounding Rock ◽  
Numerical Software ◽  
The Stability ◽  
Roadway Deformation ◽  
Soft Rock Roadway ◽  
Surrounding Rock Stress ◽  
Rock Roadway

The roof of 12501 transportation roadway of Tunlan mine is friable. To solve the problem of large roadway deformation, the bolt-mesh-anchor support scheme is put forward. With the FLAC3D numerical software in the program, the simulation analysis shows that the program can effectively increase the roadway confining pressure to improve the state of the surrounding rock stress, reduce roadway displacement and deformation and thus keep the stability of the surrounding rock. The results show that Bolt and cable support can effectively control the surrounding rock, with the roadway convergence rate small, and the support system safe.

Experimental Analysis on Microstructure and Mineral Composition of Jurassic Soft Rock in Shajihai Mining Area of Xinjiang

2013 ◽  
Vol 353-356 ◽  
pp. 24-27
Author(s):  
Xiao Lei Wang ◽  
Shun Xi Yan ◽  
Hai Qiao Wen
Keyword(s):  
Mineral Composition ◽  
Soft Rock ◽  
Mining Area ◽  
Sem Analysis ◽  
Surrounding Rock ◽  
Test Results ◽  
X Ray Diffraction ◽  
Component Content ◽  
The Stability ◽  
Soft Rock Roadway

In order to find out themicroscopic structure and determine mineral composition and relative content ofroadway soft rock in Shajihai mining area, this paper carried out experimentsof scanning electron microscope (SEM) analysis and X-ray diffraction analysis.SEM test results show that the microstructure of the surrounding rock isgenerally poor and joint, crack, pore are developed. The crack is easy toexpand under the effect of surrounding rock pressure and water, which makesrock mass more broken and greatly reduces the stability of surrounding rock.X-ray diffraction analysis test shows that the component content of clayminerals in the surrounding rock is high. Clay mineral in mudstone containsmontmorillonite and content of illite/smectite mixed layer is relativelyhigher, up to 45%. In conclusion, soft rock roadway of Shajihai mine areabelongs to the typical swelling-jointed compound soft rock. The targeted andreasonable compound transformation technology and coupling support measuresmust be adopted when supporting.

scholarly journals Numerical Simulation Analysis of New Steel Sets Used for Roadway Support in Coal Mines

Metals ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 606 ◽  
Author(s):  
Qinghai Li ◽  
Jingkai Li ◽  
Jinpeng Zhang ◽  
Changxiang Wang ◽  
Kai Fang ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Theoretical Analysis ◽  
Simulation Analysis ◽  
Coal Mines ◽  
Soft Rock ◽  
Observation Point ◽  
Surrounding Rock ◽  
Surrounding Rock Control ◽  
Roadway Support ◽  
Two Sides

The surrounding rock control is a tough issue in the roadway with the swelling soft rock. The steel set is an important material for the control of swelling soft rock roadways. However, traditional steel sets failed to prevent the expansive pressure of the soft rock. Based on traditional steel sets, this paper developed a new steel set through both theoretical analysis and numerical simulation. The results showed that the new steel set was the set with the roof beam 1000 mm from the top of the set and the floor beam 400 mm from the bottom end of the set. The maximum deformations of the roof-floor and two sides of the ventilation roadway controlled by the best-improved set at the observation point were 147 mm and 108 mm, respectively. So, the best-improved set can effectively control the surrounding rock of the ventilation roadway. This provides an effective method for the surrounding rock control in extremely soft rock roadways.

scholarly journals Research and Application of Directional Roof Cutting and Pressure Releasing Technology for Retracement Channel of 3314 Working Face in Hexi Coal Mine

2021 ◽  
Author(s):  
Jindong Cao ◽  
Xiaojie Yang ◽  
Ruifeng Huang ◽  
Qiang Fu ◽  
Yubing Gao
Keyword(s):  
Coal Mine ◽  
High Stress ◽  
Surrounding Rock ◽  
Engineering Practice ◽  
Mine Pressure ◽  
Working Face ◽  
Geological Conditions ◽  
Cutting Effect ◽  
The Stability ◽  
Two Sides

Abstract The high stress of the surrounding rock of Hexi Coal Mine easily leads to severe deformation of the retracement channel and the appearance of the mine pressure during the retreat severely affects the stability of the roadway. In order to solve the above problems, a roadway surrounding rock control technology is proposed and tested. The bidirectional energy-concentrated tensile blasting technology is used to perform directional cutting to cut off the stress propagation path. Firstly, the deformation mechanism of the roof is analyzed by establishing the deformation mechanical model of the roof of the retracement channel. Then, according to the geological conditions of working face 3314 and theoretical calculation, the key parameters of roof cutting and pressure releasing of retracement channel are determined, and through the numerical analysis of its cutting effect, the length of cutting seam is 11.5m, and the cutting angle is 10°. Finally, a field test is carried out on the retracement channel of 3314 working face to verify the effect of roof cutting. The results show that the deformation of the retracement channel and the main roadway is very small. In the process of connecting the working face and the retracement channel, the maximum roof to floor convergence is 141mm, and the two sides convergence is 79mm. After the hydraulic support was retracted, the maximum roof to floor convergence of the surrounding rock is 37 mm, and the two sides convergence is 33mm. The roof cutting and pressure releasing of the retracement channel ensures the safe evacuation of the equipment and the stability of the main roadway. The cutting effect is obvious for the release of pressure, which is of great significance to engineering practice.

scholarly journals Deformation Mechanism and Support Technology of Deep and High-Stress Soft Rock Roadway

2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Lujing Zheng ◽  
Yujun Zuo ◽  
Yafei Hu ◽  
Wei Wu
Keyword(s):  
Mechanical Properties ◽  
Bearing Capacity ◽  
High Stress ◽  
Soft Rock ◽  
Physical And Mechanical Properties ◽  
Surrounding Rock ◽  
Rock Fragmentation ◽  
The Stability ◽  
Soft Rock Roadway ◽  
Rock Roadway

In this study, the analysis and control of stability of surrounding rock in deep fractured soft rock roadway located in the underground mine of Jinfeng gold mine in Guizhou Province, China, has been investigated. The surrounding rock of roadway has been analyzed to characterize its deformation and failure mechanism through field survey, testing of rock physical and mechanical properties, in situ stress measure, analysis of mineral components of rock, and investigation of rock fragmentation degree. Based on the numerical simulation technology, the influence of different factors on the stability of roadway is studied. The physical and mechanical properties of surrounding rock and the bearing capacity of surrounding rock layer are to be improved to maintain the stability of broken soft rock roadway as high ground stress, rock fragmentation, and poor lithology leading to tunnel instability. Hence, a high-strength “cable bolt + fiber-reinforced shotcrete + steel mesh + split sets + resin bolt + cement grouting” combined support system has been proposed to improve the effective bearing structure significantly with high integrity and bearing capacity.

The Integrated Control Countermeasures on Floor Heave of Broken Soft Rock with High Ground Stress

2014 ◽  
Vol 875-877 ◽  
pp. 2259-2263 ◽  
Author(s):  
Yao Bin Li
Keyword(s):  
Integrated Control ◽  
Soft Rock ◽  
Mining Area ◽  
Stability Control ◽  
Surrounding Rock ◽  
Deep Well ◽  
Rock Stability ◽  
Geological Conditions ◽  
Floor Heave ◽  
Key Issues

The floor heave is one of the key issues of surrounding rock stability control during the deep well mining process. To solve the problem about floor heave occupying the most of roof and floor convergence deformation, the author analyzed the engineering geological conditions of broken surrounding rock and the floor heave features in PanEr Coal Mine East 2 mining area when it through the fault zone with high pressure. It pointed out that we should make full use of the reinforcement of the roof and laneway's side to limit the deformation of the floor, and make use of overbreak, prestressed anchor cable, bottom corner bolt, deep hole grouting and backfill as direct bottom control countermeasures.

scholarly journals Application of Modified Hoek–Brown Strength Criterion in Water-Rich Soft Rock Tunnel

Geofluids ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Xianghui Deng ◽  
Yuncai Wang ◽  
Rui Wang ◽  
Daohong Xia ◽  
Zhiqing Zhao
Keyword(s):  
Soft Rock ◽  
Strength Criterion ◽  
Surrounding Rock ◽  
Calculation Formula ◽  
Rock Stratum ◽  
Rock Stability ◽  
Deformation Limit ◽  
Disturbance Factor ◽  
The Stability ◽  
Rock Tunnel

When a tunnel is excavated in the water-rich soft rock stratum, the strength of the soft rock is greatly reduced due to the seepage of groundwater. The condition may result in engineering accidents, such as large deformation, limit invasion, and even local collapse of the tunnel. Therefore, it is very important to research the stability of the surrounding rock in the water-rich soft rock tunnel. The water-rich disturbance factor considering the seepage influence of groundwater and blasting disturbance is proposed, and the generalized Hoek–Brown strength criterion is modified on the basis of the immersion softening test of soft rock. In accordance with the classical elastic–plastic mechanics theory, the stress, strain, and displacement calculation formulas of the tunnel surrounding rock are derived. The displacement of tunnel surrounding rock is analyzed using the derived formula and the modified Hoek–Brown strength criterion and then compared with the measured value. Results show that the displacement of surrounding rock, which is calculated by modified Hoek–Brown strength criterion considering water-rich disturbance factor and the displacement calculation formula, is close to the measured deformation of surrounding rock in water-rich soft rock tunnel, and the error is small. Therefore, the modified Hoek–Brown strength criterion can be applied to the water-rich soft rock tunnel, and the derived displacement calculation formula can accurately calculate the deformation of tunnel surrounding rock. It is of great significance to the study of surrounding rock stability of water-rich soft rock tunnel.

Sign in / Sign up

Export Citation Format

Share Document