Rockburst prevention via destress blasting of competent roof rocks in hard coal longwall mining

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68145535%3A_____%2F18%3A00491712" target="_blank" >RIV/68145535:_____/18:00491712 - isvavai.cz</a>

Výsledek na webu

<a href="http://www.scielo.org.za/pdf/jsaimm/v118n3/09.pdf" target="_blank" >http://www.scielo.org.za/pdf/jsaimm/v118n3/09.pdf</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.17159/2411-9717/2018/v118n3a6" target="_blank" >10.17159/2411-9717/2018/v118n3a6</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Rockburst prevention via destress blasting of competent roof rocks in hard coal longwall mining

Popis výsledku v původním jazyce

Although the application of destress blasting as an active rockburst mitigation measure is not yet commonplace in hard coal longwall mining, the method is assuming heightened importance due to increases in mining depth and high horizontal stresses in the rock mass. The main goals of destress blasting are the softening of competent rock layers, the reduction of strain energy storage, and rock mass stress release, which together contribute to minimizing rockburst occurrence and risk. One such region in which destress blasting in competent rock is applied is the Upper Silesian Coal Basin, mainly in its Czech part. Here a case study of destress blasting is presented and evaluated in terms of rockburst prevention, focusing on a thick coal seam (about 5 m) subject to longwall mining under very unfavourable geomechanical conditions (great depth - 1200 m, competent rigid rocks between coal seams, unfavourable stress field due to long-term mining). Destress blasting stages were carried out in groups of between four and eight boreholes 95 mm in diameter, with the total explosive charge ranging from 2100 kg to 3750 kg, detonated regularly at distances of 43 m to 114 m ahead of the advancing longwall face. Evaluation of destress blasting based on seismic monitoring revealed that the longwall blasts were very successful in terms of rock mass stress release and decreasing the rockburst risk, with only one rockburst occurring on a roadway 210 m from the longwall face. The following longwall section was mined safely without rockburst occurrence.

Název v anglickém jazyce

Rockburst prevention via destress blasting of competent roof rocks in hard coal longwall mining

Popis výsledku anglicky

Although the application of destress blasting as an active rockburst mitigation measure is not yet commonplace in hard coal longwall mining, the method is assuming heightened importance due to increases in mining depth and high horizontal stresses in the rock mass. The main goals of destress blasting are the softening of competent rock layers, the reduction of strain energy storage, and rock mass stress release, which together contribute to minimizing rockburst occurrence and risk. One such region in which destress blasting in competent rock is applied is the Upper Silesian Coal Basin, mainly in its Czech part. Here a case study of destress blasting is presented and evaluated in terms of rockburst prevention, focusing on a thick coal seam (about 5 m) subject to longwall mining under very unfavourable geomechanical conditions (great depth - 1200 m, competent rigid rocks between coal seams, unfavourable stress field due to long-term mining). Destress blasting stages were carried out in groups of between four and eight boreholes 95 mm in diameter, with the total explosive charge ranging from 2100 kg to 3750 kg, detonated regularly at distances of 43 m to 114 m ahead of the advancing longwall face. Evaluation of destress blasting based on seismic monitoring revealed that the longwall blasts were very successful in terms of rock mass stress release and decreasing the rockburst risk, with only one rockburst occurring on a roadway 210 m from the longwall face. The following longwall section was mined safely without rockburst occurrence.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

20703 - Mining and mineral processing

Projekt

<a href="/cs/project/LO1406" target="_blank" >LO1406: Institut čistých technologií těžby a užití energetických surovin - Projekt udržitelnosti</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2018

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Journal of the Southern African Institute of Mining and Metallurgy

ISSN

2225-6253

e-ISSN

—

Svazek periodika

118

Číslo periodika v rámci svazku

3

Stát vydavatele periodika

ZA - Jihoafrická republika

Počet stran výsledku

8

Strana od-do

235-242

Kód UT WoS článku

000432337200006

EID výsledku v databázi Scopus

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