In situ stress determination from excavation-induced stress by the compact conical-ended borehole overcoring method

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68145535%3A_____%2F16%3A00462327" target="_blank" >RIV/68145535:_____/16:00462327 - isvavai.cz</a>

Výsledek na webu

—

DOI - Digital Object Identifier

—

Jazyk výsledku

angličtina

Název v původním jazyce

In situ stress determination from excavation-induced stress by the compact conical-ended borehole overcoring method

Popis výsledku v původním jazyce

The Compact Conical Borehole Overcoring (CCBO) method originally developed in Japan tondetermine stress in rock has been widely used by the Institute of Geonics, Czech Academy of Sciences. Only one borehole is required to install the CCBO instrument, measure strains and determine the full stress tensor in rock mass. To determine the pre-mining stress around the circular tunnel in undisturbed hard rock, the measurement requires a borehole of certain length to install the CCBO cell in location where the excavation does not affect the stress field.To reduce the drilling and installation costs, the Institute is developing new theoretical solutions for a short borehole strain measurement method enabling the CCBO cell installation closer to the circular tunnel. Thenproposed semi-analytical approach uses the short borehole strain measurement results, theoretical calculations of stress distribution in the elastic medium around the circular tunnel and numerical modelling, to back analyze the probable pre-mining stress tensor. This approach enables determination of pre-mining stress obtained from the short borehole strain measurements in excavation-induced zone around underground opening. Discussed here are the theoretical calculation methods, numerical modelling results and a practical example of the pre-mining stress determination from the short borehole strain measurements using the CCBO instrument.

Název v anglickém jazyce

In situ stress determination from excavation-induced stress by the compact conical-ended borehole overcoring method

Popis výsledku anglicky

The Compact Conical Borehole Overcoring (CCBO) method originally developed in Japan tondetermine stress in rock has been widely used by the Institute of Geonics, Czech Academy of Sciences. Only one borehole is required to install the CCBO instrument, measure strains and determine the full stress tensor in rock mass. To determine the pre-mining stress around the circular tunnel in undisturbed hard rock, the measurement requires a borehole of certain length to install the CCBO cell in location where the excavation does not affect the stress field.To reduce the drilling and installation costs, the Institute is developing new theoretical solutions for a short borehole strain measurement method enabling the CCBO cell installation closer to the circular tunnel. Thenproposed semi-analytical approach uses the short borehole strain measurement results, theoretical calculations of stress distribution in the elastic medium around the circular tunnel and numerical modelling, to back analyze the probable pre-mining stress tensor. This approach enables determination of pre-mining stress obtained from the short borehole strain measurements in excavation-induced zone around underground opening. Discussed here are the theoretical calculation methods, numerical modelling results and a practical example of the pre-mining stress determination from the short borehole strain measurements using the CCBO instrument.

Druh

D - Stať ve sborníku

CEP obor

—

OECD FORD obor

20703 - Mining and mineral processing

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2016

Kód důvěrnosti údajů

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

Název statě ve sborníku

Rock Mechanics and Rock Engineering: From the Past to the Future

ISBN

978-1-138-03265-1

ISSN

—

e-ISSN

—

Počet stran výsledku

4

Strana od-do

1203-1206

Název nakladatele

CRC Press, Taylor and Francis Group

Místo vydání

London

Místo konání akce

Cappadocia

Datum konání akce

29. 8. 2016

Typ akce podle státní příslušnosti

WRD - Celosvětová akce

Kód UT WoS článku

000719660400085