Abstract
Coal mining is vulnerable to multiple kinds of threat from water incursion. Many coal seams contain dissolved H2S, which may be released during mining, seriously endangering the health of workers. Orthogonal testing was used to analyze the physical and mechanical properties of composite slurries in different proportions. The results showed slurry with a water-solid ratio of 0.8:1 to have the optimal combination of properties. A uniform experimental method was used to investigate the impact of the water-cement ratio, concentration of sodium silicate, and volume of cement-sodium silicate (CS) on the setting time and consolidating strength of CS slurry. This paper provides the appropriate application scope of two grouting materials (optimized composite slurry and CS slurry), based on experimental data and the results of a large number of in situ trials. Finally, the optimized composite slurry and cement-sodium silicate slurry were used to carry out grouting of the center auxiliary transport roadway of the 3−1 coal seam at the Ningtiaota Coal Mine, operated by the Shaanxi Coal Industry Group. It was shown that the type and formula of the slurry could be changed in a timely manner, based on the water outlet and concentration of H2S at the site, achieving successful grouting reinforcement and seepage-proofing.
Highlights
The coal fields of China vary widely in terms of the age and nature of the seams, and many exhibit complex geology
Approaches to improving the strength of grouting materials have included the use of composite cement-sodium silicate, proposed by Maoyin Wu et al [7]; sodium silicate with high Baume degree or composite cement grouting with the appropriate ratio of cement, fly ash and mineral powder can increase the strength of slurry concretion
This paper presented an introductory study on the properties of composite slurry and cement-sodium silicate slurry; the results are as follows: 1. Orthogonal testing was used to analyze the physical and mechanical properties of composite slurry of different proportions
Summary
The coal fields of China vary widely in terms of the age and nature of the seams, and many exhibit complex geology. Many mines that are threatened by unpredictable water intrusion contain H2S. This presents a serious safety hazard for those working in the shaft. Traditional slurry, including pure cement slurry, cement-fly ash slurry, cement-clay slurry, and chemical slurry, all have drawbacks, and attention is turning to grouts of composite type. Approaches to improving the strength of grouting materials have included the use of composite cement-sodium silicate, proposed by Maoyin Wu et al [7]; sodium silicate with high Baume degree or composite cement grouting with the appropriate ratio of cement, fly ash and mineral powder can increase the strength of slurry concretion. It was demonstrated that neither of above two slurries was suitable for use in environment with a significant presence of H2S, and nor did they contribute to decreasing the cost of grouting
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: The Open Construction and Building Technology Journal
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
