CRITICAL GRAVITATIONAL ACCELERATION ANALYSIS ON THE STABILITY OF A TUNNEL ROOF WITH A JOINT ORIENTATION OF 60°

• Main Author: ARCHICO NARENDRA (NIM : 12114061), MUHAMMAD
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/29139
• Institution: Institut Teknologi Bandung

The mining industry’s purpose is to utilize the mineral resources contained in the earth's crust for the sake of human well-being. In some cases, valuable materials beneath the earth's surface do not provide an economic value if it is mined using a surface mining method. Hence, mining activities should be carried out using an underground mining method. Therefore, a tunnel failure analysis is essential to prevent accidents affecting the production and safety of the workers. One form of physical modeling that can be performed to analyze a tunnel failure is by using a centrifuge test. <br /> <br /> The physical model of the tunnel in the centrifuge test is made using blocks with a certain dimension. The variations for the tunnel roof blocks used are joint orientation and joint spacing. The values of the joint orientation are 60°, 90°, and 45° and the values of the joint spacing are 5.14 cm, 4 cm, and 3 cm. Then, the model is given a centrifugal force with different speeds, starting from 10 RPM, with a 2.5 RPM interval for 30 seconds until failure occured. The centrifuge test will represent the gravitational acceleration existing on the field. <br /> <br /> The experiment results show that the joint orientation on the tunnel roof affects the stability of the tunnel. The more upright the orientation is, the easier it will be for the tunnel roof to fail. In addition, the results also show that the value of joint spacing and the volume of tunnel roof failure is directly proportional. The larger the value of joint spacing is, the greater the volume of roof tunnel failure will be when given a centrifugal force.