Next Article in Journal
New Adaptive Reclosing Technique in Unbalanced Distribution System
Previous Article in Journal
Prediction in Photovoltaic Power by Neural Networks
Article Menu
Issue 7 (July) cover image

Export Article

Open AccessArticle
Energies 2017, 10(7), 1005; https://doi.org/10.3390/en10071005

Numerical Modelling of Mechanical Behavior of Coal Mining Hard Roofs in Different Backfill Ratios: A Case Study

Key Laboratory of Deep Coal Resources Mining, School of Mines, Ministry of Education of China, China University of Mining & Technology, Xuzhou 221116, China
*
Author to whom correspondence should be addressed.
Received: 21 June 2017 / Revised: 12 July 2017 / Accepted: 13 July 2017 / Published: 15 July 2017
Full-Text   |   PDF [8605 KB, uploaded 15 July 2017]   |  

Abstract

In coal mining hard roofs are one of the main factors causing the occurrence of rock bursts in working panels. To solve this problem, the solid backfill coal mining (SBCM) technique is proposed and used as an effective measure to prevent the rock bursts induced by hard roofs. However, due to the different backfill ratios of working planes, the control effects on hard roofs are quite unique. By using a numerical simulation, this study simulates the deformation of hard roofs and distributions of stress and strain energies in different roof-control backfill ratios, so as to reveal the control mechanisms of SBCM on hard roofs. The results show that, when the roof-controlled backfill ratio are 0, 40% and 60%, the ratio exerts no influence on the distributions of advanced abutment stress and strain energies. While for roof-control backfill ratios of 82.5%, 91% and 93%, the advanced abutment stress and strain energies decrease significantly, but the increment of the ratio exerts little influence on the decrease. When the roof-control backfill ratio reaches 97%, the advanced abutment stress and strain energies again decrease. In this context, the stress concentration factor is only 1.5 and the peak strain energy is 544 kJ/m3, the stress concentration factor and peak strain energy decrease by 45.7% and 63.9%, respectively, compared with the caving method. As the roof-controlled backfill ratio rises, backfill materials tend to support hard roofs, thus significantly preventing dynamic hazards. View Full-Text
Keywords: hard roof; rock burst; roof-controlled backfill ratio; strain energy hard roof; rock burst; roof-controlled backfill ratio; strain energy
Figures

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).
SciFeed

Share & Cite This Article

MDPI and ACS Style

Li, M.; Zhou, N.; Zhang, J.; Liu, Z. Numerical Modelling of Mechanical Behavior of Coal Mining Hard Roofs in Different Backfill Ratios: A Case Study. Energies 2017, 10, 1005.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Energies EISSN 1996-1073 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top