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When it comes to mining operation and civil engineering activities like tunnelling and dam constr... more When it comes to mining operation and civil engineering activities like tunnelling and dam constructing the importance of blasting cannot be underestimated. A nearly perfect estimate of explosion loading on rock mass is an essential prerequisite to initiating such activities. The ability of transmitting vibrations differs in different rock types due to their differing rock mass properties. For example, rigid competent rock types with high compressive strength and high density have a good transmitting ability. The present study focuses on different qualities of rock mass properties including good and average quality. Moreover, it is in effect a comparative study between numerical simulation and empirical equations. The results indicate that in empirical equations only compression wave of pressure are taken into account and the tensile waves are ignored. It is also demonstrated that the dynamic load on the borehole wall is more in the rock mass of good quality than in the average quality.
Journal of The Institution of Engineers (India): Series D, 2017
One of the popular methods of underground and surface excavations is the use of blasting. Through... more One of the popular methods of underground and surface excavations is the use of blasting. Throughout this method of excavation, the loading resulted from blasting can be affected by different geo-mechanical and structural parameters of rock mass. Several factors affect turbulence in underground structures some of which are explosion, vibration, and stress impulses caused by the neighbouring blasting products. In investigating the blasting mechanism one should address the processes which expand with time and cause seismic events. To protect the adjoining structures against any probable deconstruction or damage, it is very important to model the blasting process prior to any actual operation. Efforts have been taken in the present study to demonstrate the potentiality of numerical methods in predicting the specified parameters in order to prevent any probable destruction. For this purpose the blasting process was modeled, according to its natural implementation, in one of the tunnels of Siahbishe dam by the 3DEC and AUTODYN 3D codes. 3DEC was used for modeling the blasting environment as well as the blast holes and AUTODYN 3D for modeling the explosion process in the blast hole. In this process the output of AUTODYN 3D, which is a result of modeling the blast hole and is in the form of stress waves, is entered into 3DEC. For analyzing the amount of destruction made by the blasting operation, the key parameter of Peak Particle Velocity was used. In the end, the numerical modeling results have been compared with the data recorded by the seismographs planted through the tunnel. As the results indicated 3DEC and AUTODYN 3D proved appropriate for analyzing such an issue. Therefore, by means of these two softwares one can analyze explosion processes prior to their implementation and make close estimation of the damage resulting from these processes.
Journal of Mountain Science, 2011
The stability of slopes is always of great concern in the field of rock engineering. The geometry... more The stability of slopes is always of great concern in the field of rock engineering. The geometry and orientation of pre-existing discontinuities show a larger impact on the behavior of slopes that is often used to describe the measurement of the steepness, incline, gradient, or ...
When it comes to mining operation and civil engineering activities like tunnelling and dam constr... more When it comes to mining operation and civil engineering activities like tunnelling and dam constructing the importance of blasting cannot be underestimated. A nearly perfect estimate of explosion loading on rock mass is an essential prerequisite to initiating such activities. The ability of transmitting vibrations differs in different rock types due to their differing rock mass properties. For example, rigid competent rock types with high compressive strength and high density have a good transmitting ability. The present study focuses on different qualities of rock mass properties including good and average quality. Moreover, it is in effect a comparative study between numerical simulation and empirical equations. The results indicate that in empirical equations only compression wave of pressure are taken into account and the tensile waves are ignored. It is also demonstrated that the dynamic load on the borehole wall is more in the rock mass of good quality than in the average quality.
Journal of The Institution of Engineers (India): Series D, 2017
One of the popular methods of underground and surface excavations is the use of blasting. Through... more One of the popular methods of underground and surface excavations is the use of blasting. Throughout this method of excavation, the loading resulted from blasting can be affected by different geo-mechanical and structural parameters of rock mass. Several factors affect turbulence in underground structures some of which are explosion, vibration, and stress impulses caused by the neighbouring blasting products. In investigating the blasting mechanism one should address the processes which expand with time and cause seismic events. To protect the adjoining structures against any probable deconstruction or damage, it is very important to model the blasting process prior to any actual operation. Efforts have been taken in the present study to demonstrate the potentiality of numerical methods in predicting the specified parameters in order to prevent any probable destruction. For this purpose the blasting process was modeled, according to its natural implementation, in one of the tunnels of Siahbishe dam by the 3DEC and AUTODYN 3D codes. 3DEC was used for modeling the blasting environment as well as the blast holes and AUTODYN 3D for modeling the explosion process in the blast hole. In this process the output of AUTODYN 3D, which is a result of modeling the blast hole and is in the form of stress waves, is entered into 3DEC. For analyzing the amount of destruction made by the blasting operation, the key parameter of Peak Particle Velocity was used. In the end, the numerical modeling results have been compared with the data recorded by the seismographs planted through the tunnel. As the results indicated 3DEC and AUTODYN 3D proved appropriate for analyzing such an issue. Therefore, by means of these two softwares one can analyze explosion processes prior to their implementation and make close estimation of the damage resulting from these processes.
Journal of Mountain Science, 2011
The stability of slopes is always of great concern in the field of rock engineering. The geometry... more The stability of slopes is always of great concern in the field of rock engineering. The geometry and orientation of pre-existing discontinuities show a larger impact on the behavior of slopes that is often used to describe the measurement of the steepness, incline, gradient, or ...