Effect of Joint Orientation on the Breakage Behavior of Jointed Rock Mass Loaded by Disc Cutters

The factors affecting the TBM tunnel behavior in jointed rock mass is investigated. In the numerical models the concrete segment lining of TBM tunnel is concerned, which is simulated as a tube neglecting the segment joint. And the TBM tunnel construction process is simulate considering the excavation and installing of the segment linings. Some cases are analyzed with different joint orientation, joint spacing, joint strength and tunnel depth. The results show that the shape and areas of loosing zones of the tunnel are influenced by the parameters of joint sets and in-situ stress significantly, such as dip angle, spacing, strength, and the in-situ stress statement. And the stress and deformation of the tunnel lining are influenced by the parameters of joint sets and in-situ stress, too.

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Effects of joint orientation and spacing on the boreability of jointed rock mass using tunnel boring machines

Arabian Journal of Geosciences ◽

10.1007/s12517-020-06428-x ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Morteza Khosravi ◽

Ahmad Ramezanzadeh ◽

Shokrollah Zare

Keyword(s):

Rock Mass ◽

Jointed Rock ◽

Jointed Rock Mass ◽

Joint Orientation ◽

Tunnel Boring Machines ◽

Tunnel Boring ◽

Boring Machines

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Study on the breaking process of jointed rock mass by disc cutters based on digital image correlation and infrared thermography

E3S Web of Conferences ◽

10.1051/e3sconf/202123303006 ◽

2021 ◽

Vol 233 ◽

pp. 03006

Author(s):

Xie Junning ◽

Liu Bolong ◽

Zeng Nianchang

Keyword(s):

Rock Mass ◽

Digital Image Correlation ◽

Digital Image ◽

Thermal Infrared ◽

Jointed Rock ◽

Jointed Rock Mass ◽

Experimental Results ◽

Image Correlation ◽

Strain Fields ◽

Disc Cutters

Jointed rock masses are frequently encountered during the TBM excavation. To investigate the rock breakage mechanism of jointed rock mass by disc cutter and precursory information before rock failure, a series of indentation tests were performed on shear rheological test system. During the test, breaking process of specimens were recorded by digital image correlation system and thermal infrared imager simultaneously. Therefore, the strain fields and thermal infrared images of jointed rock mass by disc cutters were obtain. The experimental results show that the failure process of jointed rock mass can be divided into four stages: compaction stage, linear elastic stage, residual failure transition stage and post-failure stage. Besides, the characteristic of strain fields shows a good accordance with that of infrared radiation temperature fields at each stage. The failure of rock samples is dominated by shear failure, and the localized temperature rise is an important infrared precursor of rock fracture and instability. The experimental results are of great significance to the deep understanding of the breaking mechanism of jointed rock mass and warnings of engineering disasters.

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