Notice of Retraction: Theory and experimental study on soft rock roadway blasting destressing in deep mine

2011 ◽  
Author(s):  
Qi Zong ◽  
Luping Yan
Keyword(s):  
Experimental Study ◽  
Soft Rock ◽  
Deep Mine ◽  
Soft Rock Roadway ◽  
Rock Roadway

Research on Supporting Theory of Pressure-Bearing Ring and Yield Supporting Technology in Extremely Soft Rock Roadway

2013 ◽  
Vol 395-396 ◽  
pp. 536-543 ◽  
Author(s):  
Guang Long Qu ◽  
Jun Wang ◽  
Guo Lei Liu
Keyword(s):  
Soft Rock ◽  
Steel Tube ◽  
Surrounding Rock ◽  
Concrete Lining ◽  
Mining District ◽  
Deep Mine ◽  
Bearing Ring ◽  
Soft Rock Roadway ◽  
Specific Project ◽  
Rock Roadway

The soft rock roadway is classified by uniaxial compressive strength of rock and water-physical properties, which includes hard surrounding rock in deep mine, soft surrounding rock, and extremely soft surrounding rock. Aimed to the situation of being hard to support the extremely soft rock roadway, with combination of the specific project of return airway crossheading roadway of sea area NO.2 mining district in Beizao coal mine, a compound roadway supporting technology based on the concrete-filled steel tube support, reinforced concrete lining, with combination of yield supporting technology was used for this specific project, for which the mechanical model of the pressure-bearing ring structure was analyzed and calculated by using fixed-end arch theory in structural mechanics and Lame formula in Elastic theory. The field test results showed that this new compound roadway supporting technology was an ideal method to support the extremely soft rock roadway, which could control the deformation of roadway and realize the stability of roadway, effectively.

Experimental Study on Infrared Radiation Changes with the Fracture and Progressive Failure of the Submarine Soft Rock Roadway

2011 ◽  
Vol 105-107 ◽  
pp. 1822-1826 ◽  
Author(s):  
Yong Jun Zhang ◽  
Li Qian An ◽  
Xie Xing Miao
Keyword(s):  
Experimental Study ◽  
Infrared Radiation ◽  
Progressive Failure ◽  
Peak Load ◽  
Soft Rock ◽  
High Strength ◽  
Interaction Range ◽  
Physical Model Tests ◽  
Soft Rock Roadway ◽  
Rock Roadway

Based on the submarine soft rock supporting engineering in Beizao Mine, the physical model tests of four kinds of supports were carried out including high strength (HS) roadway without support, HS soft rock roadway with U-shape steel support (U-S-S-S), low strength (LS) roadway with bolt support (B-S), and LS roadway with U-S-S. The thermal infrared (TIR) changes with the fracture and damage of roadway are investigated. It is discovered that the TIR radiation is the stronger in the stress concentrated area, strong friction and interaction range between U-steel support and roadway than that in the stress relaxed area and week friction. The TIR temperature (TIRT) of the fracture increased higher and changed rapidly than other parts. The TIR radiation of soft rock is influenced with seawater. The TIR-anomaly appears at the stress concentrated area, interaction ranges and fractures. The TIR omens occur when load is 65%~90% of the peak load.

scholarly journals Study on the Deformation Mechanism of Soft Rock Roadway under Blasting Disturbance in Baoguo Iron Mine

2018 ◽  
Vol 2018 ◽  
pp. 1-12
Author(s):  
Hong-di Jing ◽  
Yuan-hui Li ◽  
Kun-meng Li
Keyword(s):  
Rock Mass ◽  
Deformation Mechanism ◽  
Soft Rock ◽  
Deformation Monitoring ◽  
Underground Mines ◽  
Blasting Vibration ◽  
Iron Mine ◽  
The Stability ◽  
Soft Rock Roadway ◽  
Rock Roadway

In order to study the deformation mechanism of soft rock roadway in underground mines, it is necessary not only to study the influence of the dynamic disturbance caused by the cyclic mining blasting vibration on the stability of the soft rock roadway but also to study the degradation of the roadway surrounding rock itself and other factors. The paper presented a synthetic research system to investigate the factors that influence roadway rock structure deterioration in Baoguo Iron Mine. Firstly, the stability of rock mass was analyzed from the perspective of the physical and structural characteristics of the rock mass. Afterwards, according to monitoring data of mining blasting vibration, a suitable safety blasting prediction model for Baoguo Iron Mine was determined. And then, combining the results of mining blasting vibration monitoring and deformation monitoring, the effect of cyclic mining blasting on the stability of the soft rock roadway was obtained. By systematically studying the intrinsic factors of rock quality degradation and external environmental disturbances and their interactions, this paper comprehensively explores the deformation mechanism of soft rock roadway and provides the support for fundamentally solving the large deformation problems of soft rock roadway in underground mines.

High Strength Combined Support Technology in Deep High Stress Soft Rock Roadway

2012 ◽  
Vol 524-527 ◽  
pp. 598-603
Author(s):  
Nian Jie Ma ◽  
Zhi Qiang Zhao ◽  
Hua Zhao ◽  
Li Shuai Jiang
Keyword(s):  
High Stress ◽  
Soft Rock ◽  
High Strength ◽  
Parameter Determination ◽  
Test Results ◽  
Actual Measurement ◽  
Computer Numerical Simulation ◽  
Soft Rock Roadway ◽  
Rock Roadway

In order to solve the serious damage and repeat revision problem of high stress soft rock roadway in deep -950 level of Tangshan coal mine, based on the theory of the maximum stress level, together with the actual measurement of geostress and the laboratory mechanical parameters of rock-core and computer numerical simulation, the high strength combined support technology and supporting parameters are determined and the engineering test has been done. The engineering test results show that the parameter determination of high strength combined support technology, which based on the actual measurement of geostress, can effective solve the support issue of high stress soft rock roadway and provide useful experience for similar engineering problems.

Determination of loading capacity index of a continuous miner in soft rock roadway and virtual test method

2022 ◽  
pp. 095440622110616
Author(s):  
Hong Zhang ◽  
You Chen ◽  
Zhihong Zhang ◽  
Honghong Yan
Keyword(s):  
Energy Consumption ◽  
Soft Rock ◽  
Test Method ◽  
Energy Utilization ◽  
Loading Capacity ◽  
Continuous Miner ◽  
Loading Efficiency ◽  
Wheel Loading ◽  
Soft Rock Roadway ◽  
Rock Roadway

To improve the loading efficiency and reduce energy consumption of a continuous miner in soft rock roadway, a seven-arm star wheel designed with Gaussian fitting method was proposed, and a coal loading model of the continuous miner star wheel loading mechanism was reconstructed with EDEM software. The loading capacity of the seven-arm star wheel and the three-arm star wheel of the EML340 continuous miner at different working speeds were studied respectively. The scientific and reasonable identification index was formulated and the index evaluation system of loading star wheel was established. It has been found that the performance of the loading star wheel is a collection of various identification indicators, the coal returning mass reducing the loading efficiency and increasing unnecessary energy consumption, therefore, it is difficult to identify by a single index. Loading coal and rock by the star wheel is a process that consumes energy and pays attention to output, therefore, the identification index should include two kinds of efficiency parameters and energy parameters. Rake coal torque and loading specific energy consumption have reflected the degree of energy utilization, which can be comprehensively used for preliminary design of the star wheel. The performance parameters such as loading power and loading efficiency are reliable indicators for designing and performance evaluation of the star wheel. Based on the statistical analysis of the test data, compared with the three-arm star wheel of the EML340 continuous miner, the loading efficiency of the seven-arm star wheel has been significantly improved. The loading power for coal loading has been reduced by 46%. The feasibility of the Gaussian design method of loading star wheel has been verified.

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

2013 ◽  
Vol 838-841 ◽  
pp. 1884-1890 ◽  
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.

Sign in / Sign up

Export Citation Format

Share Document