Characteristics of Roof Movement and Ground Pressure Behavior of Gob-side Entry Retaining by Roof Cutting in Continuous Mining

The mine pressure behavior characters of shallow buried coal seam differed from both shallow seam mining and general depth seam. Mine pressure observation and numerical analysis were applied to research mine pressure behavior laws in fully mechanized face of shallow buried coal seam with thick bedrock and thin alluvium. It showed that the ground subsidence level phenomenon did not appear obviously although with obvious dynamic loading of fully mechanized face during the pressure period. The appearance was due to non-synchronized fracture from two key layers in the overlying rock layers and their interaction, which leaded to roof breaking initially and caving rocks with the form of an arch. Due to the periodic breaking and caving characteristics appearing as fully cut-down and arch alternately, the periodic pressure of shallow buried coal seam face showed as different size. The conclusion could be a reference for similar working face control.

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Effects of gully terrain on stress field distribution and ground pressure behavior in shallow seam mining

International Journal of Mining Science and Technology ◽

10.1016/j.ijmst.2015.12.011 ◽

2016 ◽

Vol 26 (2) ◽

pp. 255-260 ◽

Cited By ~ 2

Author(s):

Jianwei Li ◽

Changyou Liu ◽

Tong Zhao

Keyword(s):

Stress Field ◽

Field Distribution ◽

Pressure Behavior ◽

Ground Pressure ◽

Seam Mining

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The Pressure Behavior Regularity of Workface and Simulation Optimization Analysis of Support Type Choice

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.282-283.90 ◽

2011 ◽

Vol 282-283 ◽

pp. 90-95

Author(s):

Hong Kai Dong ◽

Hou Quan Zhou

Keyword(s):

Simulation Optimization ◽

Discrete Element ◽

Mine Pressure ◽

Strata Movement ◽

Pressure Behavior ◽

Simulation Techniques ◽

Ground Pressure ◽

Geological Conditions ◽

Mining Face ◽

Overburden Strata

This paper simulated mining face advancing with discrete element software UDEC to study the mining overburden strata movement and mine pressure behavior, so as to determine reasonable supporting method. According to the simulation test data, this paper also determines the range of compaction region, support active region, pressure increase region and stable pressure region, so as to prove the reasonability of the hydraulic support type, and proposes the method of support type choice by simulation techniques. Ground pressure behavior is an inevitable phenomenon during the mining process[1-3]. It is necessary to take the appropriate supporting measures to support the surrounding rock, lest endanger the safety of personnel and engineer equipments in underground workface. More laboratory studies[4][5] and scene investigation are in the existing studies, so there is a good understanding of ground pressure behavior. The numerical simulation can be made in advance when geological conditions can be determined. It can provide corresponding suggestions for the project according to ground pressure appearing regularity founded by simulation. This paper studys the overburden strata movement and ground pressure behavior, and determines reasonable support type by simulation optimization with discrete element software[6] UDEC. And by comparing with the work field, we found evidences that the simulation optimization is feasible. with work field.

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The Influences of Key Strata Compound Breakage on the Overlying Strata Movement and Strata Pressure Behavior in Fully Mechanized Caving Mining of Shallow and Extremely Thick Seams: A Case Study

Advances in Civil Engineering ◽

10.1155/2019/5929635 ◽

2019 ◽

Vol 2019 ◽

pp. 1-11 ◽

Cited By ~ 6

Author(s):

Junmeng Li ◽

Yanli Huang ◽

Jixiong Zhang ◽

Meng Li ◽

Ming Qiao ◽

...

Keyword(s):

Numerical Simulation ◽

Abutment Pressure ◽

Simulation Software ◽

Strata Movement ◽

Key Strata ◽

Pressure Behavior ◽

Ground Pressure ◽

Working Face ◽

Overlying Strata Movement ◽

Overlying Strata

In order to analyze the impact of compound breakage of key strata on overlying strata movement and strata pressure behavior during the fully mechanized caving mining in shallow and extremely thick seams, this paper took the 1322 fully mechanized caving face in Jindi Coal Mine in Xing County as the engineering background. Under the special mining and geological condition mentioned above, UDEC numerical simulation software was applied to research the engineering problems, and results of numerical simulation were verified through the in-site measurement. The research results showed that during the fully mechanized caving mining in shallow and extremely thick seams, the inferior key strata affected by mining movement behaved in the mode of sliding instability and could not form the stable structure of the voussoir beam after breaking and caving. In addition, the main key strata behaved in the mode of rotary instability, and the caving rocks behind the goaf were gradually compacted because of the periodic instability of the main key strata. With the continuous advance of the working face, the abutment pressure of the working face was affected by the compound breakage and periodic instability of both the inferior key strata and the main key strata, and the peaks of the abutment pressure presented small-big-small-big periodical change characteristics. Meanwhile, the risk of rib spalling ahead of the working face presented different levels of acute or slowing trends. The actual measurement results of ground pressure in the working face showed that, in the working process, the first weighting interval of the inferior key strata was about 51 m and its average periodic weighting interval was about 12.6 m, both of which were basically consistent with the results of numerical simulation. The research has great significance in providing theoretical guidance and practical experience for predicting and controlling the ground pressure under the similar mining and geological conditions.

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