A historic park area and a ground cover of only 10 – 32 feet (3 – 9.8 meters) above the proposed Fort Canning Tunnel posed significant design and construction challenges. Both the owner and the contractor sought an alternative tunnel construction method to avoid extensive surface disruption in the area.
Winner of the Building Authority Singapore Award NATM Design with Two-Pass Lining System:
Gall Zeidler Consultants provided an alternative New Austrian Tunneling Method (NATM) design, utilizing continuous grouted steel pipe, pre-support, and a two-pass lining system for the mined portion of the proposed tunnel. The design earned a Merit Award at the 2008 Design & Engineering Safety Excellence Awards.