scholarly journals Numerical Simulation of Rock Mass Structure Effect on Tunnel Smooth Blasting Quality: A Case Study

2021 ◽  
Vol 11 (22) ◽  
pp. 10761
Author(s):  
Jianxiu Wang ◽  
Ansheng Cao ◽  
Jiaxing Liu ◽  
Huanran Wang ◽  
Xiaotian Liu ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Rock Mass ◽  
Layered Structure ◽  
High Speed ◽  
Numerical Test ◽  
Great Influence ◽  
Structure Effect ◽  
Rock Mass Structure ◽  
Massive Structure ◽  
Smooth Blasting

Taking the Zigaojian tunnel, Hangzhou–Huangshan high-speed railway, China, as background, the rock mass structure effect on smooth blasting quality was studied. Four rock mass structures were determined on the basis of the information collected on the tunnel site. Smooth blasting finite element models were established using LS-DYNA. The accuracy of the numerical calculation model was verified by comparing the overbreak and underbreak between the numerical simulation and monitoring. Orthogonal numerical test was used to study the rock mass structure effect through single factor and main effect analysis methods. With the decrease in rock mass integrity, the smooth blasting overbreak of tunnels with massive integrity structure, massive structure, layered structure, and cataclastic structure increased. For massive integrity structure and cataclastic structure, the peripheral hole spacing should be emphatically considered. Meanwhile, in massive structure and layered structure, the included angle and spacing of structural planes had a great influence on the smooth blasting quality. The research results could provide a reference to improve the quality of similar tunnel smooth blasting.

Study on the Rockmass Instability of Open-Pit Mine by Block Theory and Numerical Simulation Methods

2013 ◽  
Vol 353-356 ◽  
pp. 1077-1081
Author(s):  
Hai Gang Li ◽  
Zhi Jun Yang ◽  
Tong Lin Han
Keyword(s):  
Numerical Simulation ◽  
Rock Mass ◽  
Finite Difference ◽  
Surrounding Rock ◽  
Open Pit ◽  
Rock Mechanic ◽  
Mining District ◽  
Lagrangian Analysis ◽  
Rock Mass Structure ◽  
Block Theory

On the background of rock masses and field engineering geology of a mine, the feature of rock mechanics and rock mass structure of surrounding rock at mining district are analyzed. Based on the finite difference theory and block theory, FLAC3D program (Fast Lagrangian Analysis for Continuum), rock mechanic and rock mass structure results are used to construct the finite difference mechanical model, which reflected the surrounding rock stability when mining. By the numerical simulation, the mechanical effect is studied by the process of mining and its results can be used to produce some theory and actual basis.

Meshing Method of Calculating Water-Entry Flow Field at High Speed

2013 ◽  
Vol 300-301 ◽  
pp. 1144-1147
Author(s):  
Zhu Zhu ◽  
Xu Long Yuan ◽  
Ya Dong Wang ◽  
Yun Ju Yan
Keyword(s):  
Numerical Simulation ◽  
Flow Field ◽  
Unsteady Flow ◽  
High Speed ◽  
Great Influence ◽  
Water Entry ◽  
Unsteady Process ◽  
Natural Cavitation ◽  
Multi Phase

An important part of the numerical simulation is the grid which the quality has great influence on the calculation precision, and also the influence often is crucial factor in most of situation. Water-entry at high speed is a complex unsteady process, and its numerical simulation needs to take consider of natural cavitation as well as rotation of the underwater body. In this paper, a new meshing method was given with using the Layering, Smoothing and Remeshing for calculating the unsteady flow field. Numerical simulation shows that the mesh given in this paper has better quality, and can be used to calculate the multi-phase mode of water-entry at the high speed.

scholarly journals Study on the Applicability of an Improved Pile-Beam-Arch Method of Metro Station Construction in the Upper-Soft and Lower-Hard Stratum

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Xinping Guo ◽  
Annan Jiang ◽  
Shanyong Wang
Keyword(s):  
Numerical Simulation ◽  
Rock Mass ◽  
Great Influence ◽  
Horizontal Displacement ◽  
Vertical Displacement ◽  
Vertical Stress ◽  
Surface Settlement ◽  
Metro Station ◽  
Study Laboratory ◽  
The Impact

The main challenge for metro station construction is to ensure the construction schedule while minimizing the impact on the surrounding environment. Based on the characteristics of the upper-soft and lower-hard stratum in the Dalian city of China, a special structure with six pilot tunnels and three spans of the pile-beam-arch (PBA) method is proposed and applied to the construction of the Labor Park metro station. In this study, laboratory experiments, numerical simulation analysis, and field monitoring data are used to investigate the applicability of six pilot tunnels and three spans of the PBA method in the process of construction. In the process of numerical simulation, the ground surface settlement, arch vertical displacement, the horizontal displacement of rock mass on both sides of the station, and vertical stress of support structure are analyzed. The numerical simulation results are found to be in good agreement with field measurement. Furthermore, the results indicate that, in the construction of six pilot tunnels and three spans of the PBA method, pilot tunnel construction and arch construction have a great influence on the surface settlement. The part of the initial vertical support of the pilot tunnels is removed, which caused the change of the position of maximum vertical stress and the redistribution of vertical stress. Because of reinforcement by side piles on both sides of the station, the horizontal displacement of the rock mass was reduced by 44.76% compared with that without reinforcement. The six pilot tunnels and three spans of the PBA method can effectively control the surface settlement, arch vertical displacement, and horizontal displacement of the rock mass.

Dynamic Numerical Simulation for the Problem of Tunnel Rock Mass Large Deformation of a Hydropower Project in the Upper Reaches of Lancang River

2011 ◽  
Vol 250-253 ◽  
pp. 1315-1319
Author(s):  
Yu Sheng Li ◽  
Guang Peng Cao ◽  
Jie Bao
Keyword(s):  
Numerical Simulation ◽  
Rock Mass ◽  
Large Deformation ◽  
Surrounding Rock ◽  
Underground Engineering ◽  
Rock Mass Structure ◽  
Roof Fall ◽  
Relaxation Stress ◽  
Stress Environment ◽  
Dynamic Numerical Simulation

It is a very effective technology methods that using dynamic numerical simulation of discrete element method to study the large deformation problems of underground engineering rock mass which in the complex rock mass mechanics environmental conditions.Research achievements show that the development of deformation failure of the tunnel surrounding rock and the final convergence stability are mainly controlled by rock mass structure and its stress environment in the special toppling deformation rock mass. Deformation of the rock mass that in the lateral unloading and relaxation and also has a complex rock mass structure developed sustainably and progressivity over time,will eventually seriously damaged in roof fall. The surrounding rock deformation of the tunnel ,which have a good rock mass integrity and do not have the obvious unloading and relaxation stress environment, gradually tended to be stable after the initial deceleration-type development.

Numerical simulation of high-speed civil transport inlet operability with angle of attack

AIAA Journal ◽  
1998 ◽  
Vol 36 ◽  
pp. 1223-1229
Author(s):  
Ge-Cheng Zha ◽  
Doyle Knight ◽  
Donald Smith ◽  
Martin Haas
Keyword(s):  
Numerical Simulation ◽  
High Speed ◽  
Angle Of Attack

Numerical Simulation of High-Speed Crack Propagating and Branching Phenomena

2016 ◽  
Vol 37 (7) ◽  
pp. 729-739
Author(s):  
GU Xin-bao ◽  
◽  
ZHOU Xiao-ping ◽  
XU Xiao ◽  
Keyword(s):  
Numerical Simulation ◽  
High Speed

scholarly journals Stress wave propagation in different number of fissured rock mass based on nonlinear analysis

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Xiaoming Lou ◽  
Mingwu Sun ◽  
Jin Yu
Keyword(s):  
Numerical Simulation ◽  
Rock Mass ◽  
Confining Pressure ◽  
Displacement Discontinuity ◽  
Stress Wave Propagation ◽  
Theoretical Derivation ◽  
Mechanics Model ◽  
Fissured Rock ◽  
Deep Rock ◽  
Theoretical Accuracy

AbstractThe fissures are ubiquitous in deep rock masses, and they are prone to instability and failure under dynamic loads. In order to study the propagation attenuation of dynamic stress waves in rock mass with different number of fractures under confining pressure, nonlinear theoretical analysis, indoor model test and numerical simulation are used respectively. The theoretical derivation is based on displacement discontinuity method and nonlinear fissure mechanics model named BB model. Using ABAQUS software to establish a numerical model to verify theoretical accuracy, and indoor model tests were carried out too. The research shows that the stress attenuation coefficient decreases with the increase of the number of fissures. The numerical simulation results and experimental results are basically consistent with the theoretical values, which verifies the rationality of the propagation equation.

scholarly journals Evolution Pattern and Matching Mode of Precursor Information about Water Inrush in a Karst Tunnel

Water ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1579
Author(s):  
Jie Song ◽  
Diyang Chen ◽  
Jing Wang ◽  
Yufeng Bi ◽  
Shang Liu ◽  
...  
Keyword(s):  
Rock Mass ◽  
Stress Field ◽  
Displacement Field ◽  
Water Inrush ◽  
Seepage Field ◽  
Karst Tunnel ◽  
Rock Mass Structure ◽  
Evolution Pattern ◽  
Water Blocking ◽  
Precursor Information

The water inrush of the Shangjiawan karst tunnel is used to study the evolution pattern of precursor water inrush information in water-filled caves and to further reveal the matching mode of the information. The three-dimensional numerical method FLAC3D was used to simulate the evolution process of water inrush after damage to a water-blocking rock mass structure in a water-filled cave and to obtain the evolution pattern of precursor water-inrush information caused by the damage. The results show that the multifield response to the characteristic precursor information of the water-inrush pattern after the fracture of the water-blocking rock mass follows the order of stress-field displacement-field seepage-field. Further, the matching pattern of the information shows that the stress field increased first and then decreased, the displacement field always increased, and the seepage field increased first and then decreased.

Rock mass structure analysis based on seismic velocity and attenuation images

2000 ◽  
Vol 45 (13) ◽  
pp. 1211-1216 ◽  
Author(s):  
Xu Chang ◽  
Yike Liu ◽  
Hui Wang ◽  
Xing Gao
Keyword(s):  
Rock Mass ◽  
Structure Analysis ◽  
Seismic Velocity ◽  
Rock Mass Structure
Sign in / Sign up

Export Citation Format

Share Document