In situ experimental investigation of basalt spalling in a large underground powerhouse cavern

Jiang, Quan; Feng, Xia‐Ting; Fan, Yilin; Fan, Qixiang; Li, Guofeng; Pei, Shufeng; Duan, Shuqian

doi:10.1016/j.tust.2017.05.020

Cited by 89 publications

(9 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The inner surfaces of a borehole might crack or peel off when the stress reaches a certain level. Such occurrences can also be used to determine the direction of the stress [17,18,19]. In our validation of the system, we used it to observe this borehole, and found the existence of cracks at 20 m (see Fig.…”

Section: Analyses Of the Resultsmentioning

confidence: 99%

A geostress measurement method based on an integrated drilling and optical microscopic imaging system

Wang¹,

Wang²,

Han³

et al. 2018

ActaGeotechSlov

View full text Add to dashboard Cite

Conventional geostress measurement methods are limited by deficiencies including the measurable depth, the complexity, and the long duration of operation. To address these problems and achieve the measurement of geostress in deep wells under conditions of complex high pressures and high temperatures, we propose a new measurement method for geostress based on an integrated drilling and optical microscopy system. Its innovative integrated structure eliminates the problems associated with complex procedures and depth limits, and avoids rock creep caused by long delays, significantly improving the accuracy and range of the measurements. It works by using microscopic imaging and direct contact probes to capture the changes of a borehole's cross-sectional outlines before and after stress relief. The resulting images are analyzed with search circles to obtain the positions of probe apices, which can be fitted into ellipses that describe the outlines, and calculate the state of the stress. The validity and accuracy of the method was verified by indoor tests and field applications in the ZK1 borehole. The results show that: (1) the integrated system can be used to measure micrometer-grade deformations; (2) the searchcircle approach can accurately obtain the positions of probe apices; and (3) the stress measurement method based on the system is accurate and feasible.

show abstract

Section: Analyses Of the Resultsmentioning

confidence: 99%

A geostress measurement method based on an integrated drilling and optical microscopic imaging system

Wang¹,

Wang²,

Han³

et al. 2018

ActaGeotechSlov

View full text Add to dashboard Cite

show abstract

“…Spalling and rockburst are two common failure modes in deep hard-rock tunnels [7,8]. Rock spalling, embodied as parallel fractures close to the free surface, is a tensional and brittle splitting failure process with no obvious ejection performance [2,9,10]. Different from the static failure mode of spalling, rockburst is a kind of artificial earthquake induced by human activities, such as mining excavations [4-6, 11, 12].…”

Section: Introductionmentioning

confidence: 99%

Effect of Joint Density on Rockburst Proneness of the Elastic‐Brittle‐Plastic Rock Mass

Pan

Ren

Cai

2021

Shock and Vibration

View full text Add to dashboard Cite

The prediction of rockburst proneness is the basis of preventing and controlling rockburst disasters in rock engineering. Based on energy theory and damage mechanics, the quantitative functional relationship between joint density and energy density was derived. Then, the theoretical results were verified by numerical simulation and uniaxial compression test, and the effect of joint density on rockburst proneness of the elastic-brittle-plastic rock mass was discussed. The results show that the relationship between the joint density and the dissipated energy index of the jointed rock mass is a logarithmic function. With the same total input energy, the higher the joint density, the more the damage dissipation energy. Even in the case of high joint density, the rock mass still has limited resistance to external failure. Under the same joint density, the strength of parallel jointed rock mass is better than that of the cross-jointed rock mass, and the parallel jointed rock mass can accumulate more elastic strain energy and has higher rockburst proneness. The joint density is closely related to the ability of the rock mass to store high strain energy. The higher the joint density is, the weaker the ability to accumulate the elastic strain energy of rock mass is and the lower the rockburst proneness is. It is helpful to predict rockburst proneness by investigating and studying the properties of geological discontinuities. The research results have some theoretical and engineering guiding significance for the prediction of rockburst proneness of the jointed rock mass.

show abstract

“…Although great progress has been made in studying the microscopic mechanisms of rock specimens (Tang et al, 2001;Liu et al, 2002;Fang et al, 2002;Sahouryeh et al, 2002;Dyskin et al, 2003), laboratory or field experiments (Bauch et al, 2004;Wong et al, 2004;Li et al, 2011;Jiang et al, 2017;Liu et al, 2017;Gong et al, 2012;Gong et al, 2018) and numerical simulations (Zhu et al, 2010;Wang et al, 2016;Sharif et al, 2019;Wowk et al, 2019), so far there is no widely accepted theoretical explanation for splitting failure, and further improvement of theoretical methods is still needed. In this paper, the 3D geomechanical model test of splitting failure is firstly introduced, and the variations of displacement and stress around the high sidewall cavern are given.…”

Section: Introductionmentioning

confidence: 99%

Failure Mechanism and Numerical Simulation of Splitting Failure for Deep High Sidewall Cavern Under High Stress

Zhang

Wen

et al. 2021

Geotech Geol Eng

View full text Add to dashboard Cite

With the increase of the depth of the underground engineering, the phenomenon of splitting failure of the deep rock will appear, which is very different from the shallow cavern. In order to reveal the formation mechanism of splitting damage, mechanical model tests and numerical simulations of splitting damage were carried out respectively. Using the Pubugou Hydropower Station as the engineering background, a three-dimensional (3D) geomechanical model test was conducted relying on a high stress three-dimensional load test system. The splitting damage phenomenon of high sidewall cavern was observed, and the oscillation variations of displacement and stress were measured. Based on strain gradient theory and continuum damage mechanics, an elastic-plastic damage softening model for splitting damage was established. The relationship between rock damage and energy dissipation was analyzed. Based on the strain energy density theory, the splitting damage criterion based on the strain gradient is established. A numerical analysis method for splitting damage was proposed, and a regional disintegration calculation program was developed based on a commercial finite element code. The numerical simulation results are in basic agreement with the 3D geomechanical model test.

show abstract

In situ experimental investigation of basalt spalling in a large underground powerhouse cavern

Cited by 89 publications

References 46 publications

A geostress measurement method based on an integrated drilling and optical microscopic imaging system

A geostress measurement method based on an integrated drilling and optical microscopic imaging system

Effect of Joint Density on Rockburst Proneness of the Elastic‐Brittle‐Plastic Rock Mass

Failure Mechanism and Numerical Simulation of Splitting Failure for Deep High Sidewall Cavern Under High Stress

Contact Info

Product

Resources

About