scholarly journals Progressive failure and friction motion characteristics of contact surface of composite rock mass

2021 ◽  
Vol 303 ◽  
pp. 01037
Author(s):  
Zhao Jinhai ◽  
Zhang Xinguo ◽  
Pan Haiyang ◽  
Chen Juntao
Keyword(s):  
Mechanical Properties ◽  
Rock Mass ◽  
Contact Surface ◽  
Failure Process ◽  
Single Fracture ◽  
Normal Contact ◽  
Deep Rock Mass ◽  
Failure Evolution ◽  
Deep Rock ◽  
The Relationship

The structural planes existing in natural rock mass can control the failure process of rock mass. Based on the progressive response-stability failure process of a single fracture interface, the relationship between progressive response and material failure of composite rock mass is discussed. The method of friction contact plane analysis in PANDAS numerical analysis software is applied to explore the correlation between the movement and mechanical properties of composite rock mass under external forces. The motion index is mainly represented by the sliding speed and distance of the contact surface, while the mechanical properties are mainly explained by the normal contact force, the friction of the contact surface, the friction coefficient and the material damage. The relationship between these six variables illustrates the progressive response relationship during the movement of the composite rock mass. Based on the static and progressive characteristics of the progressive response process of deep rock mass engineering, the failure evolution law and energy dissipation law of composite rock mass loading process and the synergistic failure characteristics of composite rock mass are discussed. The scientific problems that need to be studied in the structure, deformation and failure of deep rock mass are put forward. The reference is provided for the failure law of fractured rock mass in water inrush process under the influence of mining, as well as fault plate material and the study of mechanical state of rock mass in fault fracture zone.

Microseism Induced by Transient Release of In Situ Stress During Deep Rock Mass Excavation by Blasting

2012 ◽  
Vol 46 (4) ◽  
pp. 859-875 ◽  
Author(s):  
Jianhua Yang ◽  
Wenbo Lu ◽  
Ming Chen ◽  
Peng Yan ◽  
Chuangbing Zhou
Keyword(s):  
Rock Mass ◽  
In Situ Stress ◽  
Deep Rock Mass ◽  
Deep Rock

scholarly journals Study on the Generation Mechanism and Development Law of the Zonal Disintegration in Deep Burial Tunnels

2020 ◽  
Vol 2020 ◽  
pp. 1-16
Author(s):  
Xiaohui Ma ◽  
Jihong Wei ◽  
Jin Liu ◽  
Zezhuo Song ◽  
Yuxia Bai
Keyword(s):  
Mechanical Properties ◽  
Rock Mass ◽  
Maximum Stress ◽  
Axial Stress ◽  
Axial Direction ◽  
Tensile Failure ◽  
Zonal Disintegration ◽  
Nonlinear Characteristics ◽  
Deep Rock ◽  
New Phenomena

In the development of underground spaces, we found that the mechanical properties of rock mass often demonstrate strong nonlinear characteristics. Some new phenomena emerge in deep rock mass engineering. This includes zonal disintegration and rock burst. Zonal disintegration is very important in deep tunnels. In this paper, we start with the mechanical properties of deep rocks to understand the preconditions for zonal disintegration. Using the Failure Approach Index (FAI), the process of zonal disintegration can be modeled by FLAC (FISH language). Our results indicate that tensile failure in the Supporting Pressure Zone (SPZ) is a precondition for zonal disintegration. Various factors that affect the generation of zonal disintegration are studied. When the maximum stress is in the axial direction, zonal disintegration will be present in deep tunnels. The high axial stress is necessary for zonal disintegration. We will present a zonal disintegration simulation in one coal mine for comparison with the borehole teleview data. We suggest some measures to prevent the development of zonal disintegration.

Numerical Study on Zonal Disintegration of Deep Rock Mass Using Three-Dimensional Bonded Block Model

2019 ◽  
Vol 2019 ◽  
pp. 1-12 ◽  
Author(s):  
Qingteng Tang ◽  
Wenbing Xie ◽  
Xingkai Wang ◽  
Zhili Su ◽  
Jinhai Xu
Keyword(s):  
Rock Mass ◽  
Fracture Zone ◽  
Numerical Study ◽  
Confining Pressure ◽  
Surrounding Rock ◽  
Zonal Disintegration ◽  
Block Model ◽  
Deep Rock Mass ◽  
Damaged Zone ◽  
Deep Rock

Zonal disintegration, a phenomenon of fractured zones and intact zones distributed alternately in deep rock mass, is different from the excavation-damaged zone of shallow rock mass. In this study, bonded block model of 3DEC was employed to study the fracture mode and origination condition of zonal disintegration. Initiation, propagation, and coalescence progress of fracture around the roadway boundary under different triaxial stress conditions are elaborated. Numerical simulation demonstrated that zonal disintegration may occur when the direction of maximum principal stress is parallel to the roadway axis. It is interesting to find that the fracture around the roadway boundary traced the line of a spiral line, while slip-line fractures distributed apart from the roadway boundary. The extent of the alternate fracture zone decreased as the confining pressure increased, and alternate fracture zone was no longer in existence when the confining pressure reaches a certain value. Effects of roadway shape on zonal disintegration were also studied, and the results indicated that the curvature of the fracture track line tends to be equal to the roadway boundary in shallow surrounding rock of the roadway, while the fractures in deep surrounding rock seems unaffected by the roadway shape. Those findings are of great significance to support design of deep underground openings.

Research on Support Technique for Excavation Process of Deep Rock Mass

2013 ◽  
Vol 438-439 ◽  
pp. 1249-1252
Author(s):  
Hong Xiao Wu ◽  
Song Lin Yue ◽  
Cun Cheng Shi ◽  
Xiao Hu ◽  
Cheng Chu ◽  
...  
Keyword(s):  
Rock Mass ◽  
High Strength ◽  
Surrounding Rock ◽  
Support Program ◽  
Tunnel Excavation ◽  
Deep Rock Mass ◽  
Rock Stability ◽  
Excavation Process ◽  
Deep Rock ◽  
Fracturing Mechanism

In the deep rock mass surrounding, rock burst, large deformation, zonal fracturing and phenomena like these may occur in the tunnel excavation process. When zonal fracturing happens, it is essential to reconsider the types of support, the boundary of support and the approach of tunnel excavation. In this paper, the control theory about the surrounding rock stability under high pre-existing stresses was researched, and the efficient support form which was the combination of high strength anchor bar and anchor cable was ascertained to be adaptive to deep tunnel excavation. According to the deformation and zonal fracturing mechanism of the surrounding rock, a comprehensive support program that combined intensive short anchor bars and long anchor cables was established, and the numerical simulation was carried out to verify the feasibility of the support form.

The Influence of the Suspension on the Phenomena of Wheel-Rail Contact

2015 ◽  
Vol 809-810 ◽  
pp. 1061-1066
Author(s):  
Ioan Sebeşan ◽  
Valeriu Ştefan
Keyword(s):  
Contact Surface ◽  
Contact Problems ◽  
Contact Forces ◽  
Dynamic Loads ◽  
Friction Forces ◽  
Normal Contact ◽  
The Moment ◽  
The Relationship ◽  
Contact Pressures ◽  
Pivoting Friction

Efficient use of adhesion between wheels and rails involves a good knowledge of this phenomenon, in order to equip the vehicle with adequate facilities and systems that protect the vehicle and the rail. The loading of the vehicle's axle with dynamic loads in vertical and horizontal planes, are to be developed in the area of contact, both normal stress and shear distributed stress, their sum giving the friction force and the moment of pivoting friction (spin). This makes the wheel-rail contact problems take the two aspects of the study, namely the problem of normal and tangential contact issue. The normal contact problem involves regular geometric shape bodies, determining the size of the resulting contact surface, the distribution of the normal contact pressures and the relationship between the proximity of the bodies and the normal contact force. Solving the problem of the tangential wheel-rail contact is about to establish the correlation between the creepage, normal contact forces and friction forces, and also the ratio between the adherent contact surface and the nominal contact surface where the creepage ocurs.

Sign in / Sign up

Export Citation Format

Share Document