The Challenge of TBM Push-through and Mine-through in Malaysia MRT Line 2
During feasibility study and design stage of an underground subway, the common method of TBM crossing of intermediate station, i.e. push-through and mine-through, which basically can be affirmed for detail deign, however the changes of environment and condition of certain project, such as possession of land, unanticipated geological condition, work planning, operation actual situation of excavation works and etc., will result to the method of TBM Crossing of station might be changed and optimized even though the project is on-going. In order to reduce the impacts on station design of earth retaining system, such as diaphragm wall, pile and horizontal support, and to induce the time and cost-savings, as well, for the excavation and first stage concrete, the optimization of TBM Crossing of station is necessary and worth-trying, There will be a lot of challenges, in terms of revised design, construction technology, sequence, operation, safety and risk control have to manage when a revised method is adopted. Therefore, the challenges on advantage or disadvantage of using jack lifting system for TBM and comprehensive analysis will be discussed and presented in this paper based on Malaysia MRT Line 2 project.