Abstract
The size of the construction projects become huge and complex, and the depth of excavation for the underground structures become deeper. Also the working area is not enough for loading materials and temporary facilities. This is the most case of recent construction projects in downtown area. Top-down is the most useful method for this kind of construction projects. Top-down construction method consists of supporting method, retaining wall type, foundation type and construction direction such as up-down or up-up. construction managers have to select sub-elements for top-down construction method in planning phase. This study is to suggest the sub-elements selection model for the top-down construction method, and the case study is conducted for evaluating this model.