This paper describes the influence of joint spacing and joint orientation on the penetration rate of a Tunnel Boring Machine(TBM) disc cutter as modeled by the Discrete Element Method(DEM).The input data for the simul...This paper describes the influence of joint spacing and joint orientation on the penetration rate of a Tunnel Boring Machine(TBM) disc cutter as modeled by the Discrete Element Method(DEM).The input data for the simulations were obtained from the sandstone along the Alborz tunnel that is currently being excavated in Iran using a 5.2 m diameter open TBM.Three joint spacings,150,200,and 300 mm,were modeled together with seven values of joint orientation;0°,15°,30°,45°,60°,75°,and 90°.The results show that the penetration increases when joint orientation increases from 0° to 75°,but it decreases as the joint orientation increases further from 75° to 90°.This is true for each joint spacing.In addition,for a given joint orientation increasing the joint spacing causes the TBM penetration to decrease.The optimum joint orientation,from the viewpoint of TBM penetration,is about 60-75°.展开更多
Due to various geological processes such as tectonic activities fractures might be created in rock mass body which causes creation of blocks with different shapes and sizes in the rock body. Exact understanding of the...Due to various geological processes such as tectonic activities fractures might be created in rock mass body which causes creation of blocks with different shapes and sizes in the rock body. Exact understanding of these blocks geometry is an essential issue concerned in different domains of rock engineering such as support system of underground spaces built in jointed rock masses, design of blasting pattern, optimization of fragmentation, determination of cube blocks in quarry mines, blocks stability, etc. The aim of this paper is to develop a computer program to determine geometry of rock mass blocks in two dimensional spaces. In this article, the geometry of jointed rock mass is programmed in MATLABTM.展开更多
文摘This paper describes the influence of joint spacing and joint orientation on the penetration rate of a Tunnel Boring Machine(TBM) disc cutter as modeled by the Discrete Element Method(DEM).The input data for the simulations were obtained from the sandstone along the Alborz tunnel that is currently being excavated in Iran using a 5.2 m diameter open TBM.Three joint spacings,150,200,and 300 mm,were modeled together with seven values of joint orientation;0°,15°,30°,45°,60°,75°,and 90°.The results show that the penetration increases when joint orientation increases from 0° to 75°,but it decreases as the joint orientation increases further from 75° to 90°.This is true for each joint spacing.In addition,for a given joint orientation increasing the joint spacing causes the TBM penetration to decrease.The optimum joint orientation,from the viewpoint of TBM penetration,is about 60-75°.
文摘Due to various geological processes such as tectonic activities fractures might be created in rock mass body which causes creation of blocks with different shapes and sizes in the rock body. Exact understanding of these blocks geometry is an essential issue concerned in different domains of rock engineering such as support system of underground spaces built in jointed rock masses, design of blasting pattern, optimization of fragmentation, determination of cube blocks in quarry mines, blocks stability, etc. The aim of this paper is to develop a computer program to determine geometry of rock mass blocks in two dimensional spaces. In this article, the geometry of jointed rock mass is programmed in MATLABTM.
