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Rock burst usually occurs as a violent failure and release of strain energy in high stress and deep underground mines and tunnels. This phenomenon usually occurs at depths over than 600 m in rocks with uniaxial compressive strength of over 140 MPa. As a result of this phenomenon, rock fragments are thrown through the air, which may cause accident and damage to workers and equipment. Therefore, it is necessary to have a good knowledge of rock burst and its mechanism. In this study, the analysis of rock bursts has been conducted by using of data obtained from the laboratory, field, and literature review that by using empirical methods and rock bursting evaluation values, the sensitive points in the route of tunnel were identified. The tunnel being analyzed is a waterway tunnel with 11 kilometer in length passing through high mountains with depths of approximately 1200m from the surface. Because the tunnel runs deep under the mountain, many dynamic rock bursts may be occur. The tunnel begins at Sabzkuh drainage basin and terminates at Choghakhor dam reservoir in western part of Iran. the route of tunnel is located in Zagros fold belt and middle alpine fold belt that consist various types of rock mass including stiff, weak and brecciaed units.
Various factors such as physical and geometrical properties of pressure cell, properties of surrounding media and installation techniques seriously affect the accuracy of total pressure measurement within soil or concrete structure. In this study a numerical code was used to simulate some of factors affecting calibration coefficient and steps of installation in soil and tunnel concrete lining, for this purpose more than 1200 elastic 3D analysis for various installation situations performed. The results show for pressure cell in soils, geometric factors and compaction quality of the surrounding material greatly affect on the precision of measurement and for pressure cells that are installed in tunnel concrete lining, the most important factor in the installation method, is the place that pressure cell is installed in respect to the stress concentration.