|
|
|
| Advance stress release construction technology of small pilot tunnel in TBM strong rock burst tunneling section |
| ZHAO Yi
|
| China Railway Tunnel Stock Co., Ltd., Zhengzhou 450000, Henan, China |
|
|
|
|
Abstract In order to reduce or avoid the disaster of rockburst during the construction of the long and deep tunnel TBM, the small pilot tunnel excavation technology to release the stress of the surrounding rock in the tunnel in advance was adopted, and the stress release effect through the microseismic monitoring equipment was monitored. The results showed that the excavation of the small pilot tunnel could effectively release the stress in the tunnel and reduce the intensity and frequency of rock bursts. On this basis, the effects of different single-shot doses and the cross-sectional dimensions of small pilot holes on stress release were studied. The results showed that the single-shot dose was basically proportional to the microseismic monitoring data, that was, within a certain range, the greater the single-shot dose was, the better the stress relief effect was; the larger the cross-section size was more conducive to stress relief. In actual engineering, the stress should be released as much as possible based on the actual situation and under the premise of ensuring safety.
|
|
Received: 11 August 2021
Published: 20 March 2022
|
|
|
|
|
|
|
|
