Projects

Description

The Pakwashan Tunnel, a 5 kilometer long twin-tube expressway tunnel central Taiwan.
Facilities in this 10.5 m wide tunnel include Control systems for air conditioning, lighting, electrical supply, traffic surveillance, fire protection, etc., and one vent shaft.
The Pakwashan Tunnel stands out not only because it is the second longest roadway tunnel in Taiwan, but also because it is situated in the Tokoshan Gravel Formation, a layer of gravel with sand having geological conditions never encountered before in other construction projects, and requiring design considerations much different from that of rock tunnels.

CECI’s scope of work includes surveying, testing, geological investigation, planning and design of the Pakwashan Tunnel. After a careful evaluation, the New Austrian Tunneling Method (NATM) was adopted for the design, and supplementary methods were selected for drainage and grouting.
Construction for the project began in November 1996 and its completion and opening to traffic in April 2005 marked a major milestone in the advancement of tunnel engineering technology in Taiwan.
Observations and engineering knowledge gathered from this special project and experience will serve as an invaluable reference for other gravel tunnels constructed
in the future.