THE EFFECT OF SHOTCRETE CHARACTERISTIC ON THE SAFETY FACTOR VALUE IN THE TUNNEL MODELLING USING TWO DIMENTION FINITE ELEMENT METHOD

• Main Author: WICAKSONO (NIM : 12113028), PROBO
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/29998
• Institution: Institut Teknologi Bandung

Underground mining methods requires the construction of tunnels. Mostly the tunnels need to be supported in order to keep the surrounding rocks from collapsing. There are many varieties of tunnel supporting methods that can be used, one of which is shotcrete. An alternative to strengthening shotcrete is to add fiber into it. Therefore, this study was aimed to find out how the influence of fiber that was added into the shotcrete on the tunnel safety factor. <br /> <br /> <br /> <br /> <br /> Research began with the preparation of concrete samples with different fiber compositions. The concrete samples were tested in the uniaxial and triaxial compressive strength test to find out the characteristics of its mechanical properties. There were five fiber composition in the shotcrete used in this study: 0 ; 0.404 ; 1.778 ; 1,139 ; 4,501 grams. Then the characteristics of the mechanical properties of each shotcrete were modeled as a supporting material on the tunnel model using RS2 software. Then the value of tunnel safety factor will be calculated at four different points. <br /> <br /> <br /> <br /> <br /> The results showed that the addition of fiber in the shotcrete will initially increase the value of the safety factor. Then the more fiber added to the shotcrete composition the lower the value of the safety factor in the long-term. Additionally it was also found that shotcrete variations with fiber composition of 0.404 grams will provide the most optimum security factor value which is 1.63. <br />