Experimental Study on Failure Mechanism of Soft Rock Roadway in Yangcheng Coal

For the mutual disturbance several roadway excavation, it is difficult to support the roadway and damage is more serious, the original supporting scheme has been out of action, so the article by using the method of field test, theoretical analysis and laboratory experiments on the Yangcheng coal mine soft rock roadway destruction mechanism of in-depth study, based on the theoretical and experimental data measured results were analyzed, and according to the deformation analysis of Yangcheng mine lane, the failure characteristics and causes of roadway, also according to each drill hole core lithology and laboratory test, the basic physical and mechanical parameters, provides a reliable data of Yangcheng coal mine soft rock roadway failure mechanism, for similar geological conditions of coal seam mining also provides practical guidance significance.

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Study on Stability for Intersection of Deep Soft Rock Roadway

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.243-249.2666 ◽

2011 ◽

Vol 243-249 ◽

pp. 2666-2669

Author(s):

Zhan Jin Li ◽

Yang Zhang ◽

Xue Li Zhao

Keyword(s):

Coal Mine ◽

Soft Rock ◽

Intersection Problem ◽

The Third ◽

Geological Conditions ◽

Control Stability ◽

Soft Rock Roadway ◽

Crossing Point ◽

Coupling Support ◽

Rock Roadway

With the depth increasing continuously, more complicated of geological conditions, will make intersection in deep soft rock roadway is very difficult to support. In order to solve the intersection problem of difficult to support, combined with the third levels of the Fifth Coal Mine of Hemei, the coupling supporting design—anchor-mesh-cable + truss to control stability of crossing point—is proposed. Based software of FLAC3D, simulate the program applicable in deep soft rock roadway intersection. Application results show that the coupling support technology of anchor-mesh-cable + truss can effectively control the deformation of intersection in deep soft rock roadway.

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Failure Mechanism Analysis and Support Design for Deep Composite Soft Rock Roadway: A Case Study of the Yangcheng Coal Mine in China

Shock and Vibration ◽

10.1155/2015/452479 ◽

2015 ◽

Vol 2015 ◽

pp. 1-14 ◽

Cited By ~ 11

Author(s):

Bangyou Jiang ◽

Lianguo Wang ◽

Yinlong Lu ◽

Shitan Gu ◽

Xiaokang Sun

Keyword(s):

Failure Mechanism ◽

Coal Mine ◽

Failure Mechanisms ◽

Soft Rock ◽

Deformation Monitoring ◽

Surrounding Rock ◽

Support Design ◽

Soft Rock Roadway ◽

Rock Roadway

This paper presented a case study of the failure mechanisms and support design for deep composite soft rock roadway in the Yangcheng Coal Mine of China. Many experiments and field tests were performed to reveal the failure mechanisms of the roadway. It was found that the surrounding rock of the roadway was HJS complex soft rock that was characterized by poor rock quality, widespread development of joint fissures, and an unstable creep property. The major horizontal stress, which was almost perpendicular to the roadway, was 1.59 times larger than the vertical stress. The weak surrounding rock and high tectonic stress were the main internal causes of roadway instabilities, and the inadequate support was the external cause. Based on the failure mechanism, a new support design was proposed that consisted of bolting, cable, metal mesh, shotcrete, and grouting. A field experiment using the new design was performed in a roadway section approximately 100 m long. Detailed deformation monitoring was conducted in the experimental roadway sections and sections of the previous roadway. The monitoring results showed that deformations of the roadway with the new support design were reduced by 85–90% compared with those of the old design. This successful case provides an important reference for similar soft rock roadway projects.

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A case study on large deformation failure mechanism of deep soft rock roadway in Xin'An coal mine, China

Engineering Geology ◽

10.1016/j.enggeo.2016.12.012 ◽

2017 ◽

Vol 217 ◽

pp. 89-101 ◽

Cited By ~ 134

Author(s):

Sheng-Qi Yang ◽

Miao Chen ◽

Hong-Wen Jing ◽

Kun-Fu Chen ◽

Bo Meng

Keyword(s):

Large Deformation ◽

Failure Mechanism ◽

Coal Mine ◽

Soft Rock ◽

Soft Rock Roadway ◽

Rock Roadway

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A Case Study on Large Deformation Failure Mechanism and Control Techniques for Soft Rock Roadways in Tectonic Stress Areas

Sustainability ◽

10.3390/su11133510 ◽

2019 ◽

Vol 11 (13) ◽

pp. 3510 ◽

Cited By ~ 6

Author(s):

Xue ◽

Gu ◽

Fang ◽

Wei

Keyword(s):

Numerical Simulation ◽

Large Deformation ◽

Failure Mechanism ◽

Support System ◽

Soft Rock ◽

Tectonic Stress ◽

Geological Conditions ◽

Soft Rock Roadway ◽

Rock Roadway

Large deformation and failure of soft rock are pressing problems in the mining practice. This paper provides a case study on failure mechanisms and support approaches for a water-rich soft rock roadway in tectonic stress areas of the Wangzhuang coal mine, China. Mechanic properties of rock mass related to the roadway are calibrated via a geological strength index method (GSI), based on which a corresponding numerical simulation model is established in the Universal Discrete Element Code (UDEC) software. The failure mechanism of the roadway under water-saturating and weathering conditions is revealed by field tests and numerical simulation. It is found that the stress evolution and crack development are affected by weathering and horizontal tectonic stresses. The roadway roof and floor suffer from high stress concentration and continuous cracking, and are consequently seen with rock failure, strength weakening, and pressure relief. Unfortunately, the current support system fails to restrain rock weathering and strength weakening, and the roadway is found with serious floor heave, roof subsidence, and large asymmetric deformation. Accordingly, a new combined support system of “bolt–cable–mesh–shotcrete + grouting” is proposed. Moreover, numerical simulation and field testing are conducted to validate the feasibility and effectiveness of the proposed approach, the results of which demonstrate the capacity of the proposed new support method to perfectly control the surrounding rock. Findings of this research can provide valuable references for support engineering in the soft rock roadway under analogous geological conditions.

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Failure mechanism of Mesozoic soft rock roadway in Shajihai coal mine and its surrounding rock control

International Journal of Mining Science and Technology ◽

10.1016/j.ijmst.2014.10.019 ◽

2014 ◽

Vol 24 (6) ◽

pp. 853-858 ◽

Cited By ~ 8

Author(s):

Yue Yuan ◽

Yongjian Zhu ◽

Weijun Wang ◽

Weijian Yu

Keyword(s):

Failure Mechanism ◽

Coal Mine ◽

Soft Rock ◽

Surrounding Rock ◽

Surrounding Rock Control ◽

Soft Rock Roadway ◽

Rock Roadway

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Strength Assessments of Concrete-Filled Steel Tubular Support of Soft Rock Roadway

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.838-841.1884 ◽

2013 ◽

Vol 838-841 ◽

pp. 1884-1890 ◽

Cited By ~ 1

Author(s):

Guang Long Qu ◽

Yan Fa Gao ◽

Liu Yang ◽

Bin Jing Xu ◽

Guo Lei Liu ◽

...

Keyword(s):

Bearing Capacity ◽

Coal Mine ◽

Soft Rock ◽

Surrounding Rock ◽

Flexural Performance ◽

Laboratory Test Results ◽

Different Types ◽

Soft Rock Roadway ◽

Core Concrete ◽

Rock Roadway

Compared with I-shaped and U-shaped supports in soft rock roadway, concrete-filled steel tubular (CFST) support, as a new supporting form, has stronger bearing capacity with reasonable price. So it is becoming more and more popular in roadway supporting of coal mine in China. In this article, the surrounding rock in soft rock roadway was classified into three different types: hard rock in deep coal mine, soft surrounding rock, extremely soft surrounding rock. And, according to the characteristics of deformation failure of the CFST support and the surrounding rock in the industrial tests, three different strength assessments, including assessment of axial compressive strength, assessment of lateral flexural performance, assessment of hardening rate of core concrete, were proposed through mechanical analysis and laboratory tests for the three different types of the surrounding rock, respectively. Moreover, aimed to insufficient flexural strength of the support or low hardening rate of the core concrete in some of the roadway supporting, strengthening lateral flexural performance or making early strength concrete was necessary for the above unfavorable situations. The laboratory test results showed that the ultimate bearing capacity for the CFST support with φ194*8mm of steel tube reinforced by φ38mm round steel was 31% greater than that of the unreinforced one, 177% greater than that of the U-shaped one with equivalent weight per unit length.

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