Drill and blast method pdf file

In this way the shaft is sunk in a series of short wooden cylinders. Hole array is the arrangement of blastholes both in plan and section. Some controlled blasting methods used to reduce overbreak and backbreak beyond. This tunneling method involves the use of explosives. Pdf optimisation of drill and blast parameters using. Its suitability for medium to hard ground conditions has been well recorded. The method can be used in all types of rocks and the initial cost is lower than. In conventional core drilling method a complete analysis cannot be performed due to the lack of core orientation. The outcome of this thesis was to translate the standard of each country to english and to compare them with an example cases.

The drill and blast method is the most widely used technique for rock excavation in tunnelling and underground projects. Pdf stability problems in drillandblast tunnels caused. It is practiced most often in mining, quarrying and civil engineering such as dam, tunnel or road construction. The results showed that the mean fragmentation of the mine using current drill and blast parameters were below the expected mean fragment size of 415 mm. As the piles are driven down, the ground is excavated, and a circular crib is put in every few feet. Orientation of the core can be easily done with a core orientator. Vibration control in urban drill and blast tunneling. All of blastholes are fired and the rock within the planned round is well.

The method can be used in all types of rocks and the initial cost is lower than the mechanical method like tbm. Stability problems in drillandblast tunnels caused by faulted rock could tbm tackle most of these cases, or not. In the world of underground construction, there are two main methods for the excavation of tunnels in rock. The result of rock blasting is often known as a rock cut. Rock blasting consists of drilling holes in a rock mass. Drilling and blasting as a tunnel excavation method researchgate. Media in category drill and blast method tunneling the following 5 files are in this category, out of 5 total. Drilling and blasting an overview sciencedirect topics. Drilling and blasting is the controlled use of explosives and other methods such as gas pressure blasting pyrotechnics, to break rock for excavation. Pdf drilling and blasting as a tunnel excavation method. Drill and blast method is mostly used method for the excavation throughout the world. Using triple tube core barrels and van ruth downhole device, core can be recovered and oriented. Line drilling provides a plane of weakness to which a primary blast may. Drill and blast pattern the drilling program will be based on 2 rows of 212 inch diameter holes drilled with a grid spacing of approximately 3 feet by 5 feet along the ditch line.