#TITLE_ALTERNATIVE#

• Main Author: KARIAN (NIM : 22110028), TRI
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/20585
• Institution: Institut Teknologi Bandung

Underground coal mining method is an alternative mining method that can be used to fulfill the increasing demand of coal. One of underground coal mining methods which is widely applied in the world is longwall method. This method is categorized as caving method. Panel area which is mined out is allowed to fall. This area is known as go out and fall (goaf) area. The purpose is to reduce stress load at mining front and power roof support so that mining activity can be carried out safely. As the consequences, surface above the underground mining is potentially to subside. Regarding that matter, it is important to study surface subsidence prediction <br /> <br /> <br /> and its characteristics. Surface subsidence characteristics are consist of three things which are subsidence maximum value, subsidence area, and subsidence profile. With this prediction, it is expected that subsidence that may occur can be anticipated so <br /> <br /> <br /> the impact on the environment will be minimum. Subsidence characteristic prediction is carried out using three methods which are numerical method using <br /> <br /> <br /> distinct element 3D model, empirical method using UK National Coal Board Chart and physical model using centrifuge device. Based on the analysis, empirical method can only give prediction of subsidence maximum value and subsidence profile for single panel extraction. Numerical method can give further prediction which consists of all subsidence characteristic for both single panel extraction and more than one panel extraction. Physical model can also predict all subsidence characteristics and subsidence process <br /> <br /> <br /> time for both single panel extraction and more than one panel extraction but has constraint in the device ability. There is difference between subsidence maximum value predicted by numerical method and empirical method where the subsidence maximum value of numerical method is 30-40% lower than the empirical method. Subsidence <br /> <br /> <br /> maximum value of empirical method is always higher than the numerical ones but the area of subsidence is always lower than the numerical ones. Moreover, based on <br /> <br /> <br /> comparison with physical model, numerical method prediction is relatively close to physical model prediction compared to the empirical ones.