| Title |
A Case Study on Penetrating Hard Rock with Alternative Methods of Shield TBM for Weathered Layer in Subway Construction |
| Keywords |
shield TBM;hard rock boring;schedule delay;boring stoppage;alternative method;쉴드 TBM 공법;경암 굴착;공기지연;대체공법;경암 발파;제거 공법 |
| Abstract |
Recently, the Shield TBM (Tunnel Boring Machine) construction method is used gradually to increase at the Tunnel Constructin site. However the design and application of the Shield TBM were carried out without sufficient investigation of the ground conditions in the construction site. Due to insufficient understanding to the corresponding equipment is frequently occurring unexpected construction cost and extension of a construction period. The most suitable alternative construction method was determined by analyzing tunneling rate, duration, construction cost of shield machine and tunneling data of alternative method. The result of the case study is suggested as follows. First, the accurate soil exploration on the construction site should be preceded to prevent from tunneling stoppage and schedule delay. Second, the most suitable selection of the shield machine to the ground conditions of the construction site should be executed based on the investigation. Third, the best alternative method for boring of hard rock section is "hard rock blasting after open cut and cover method". |