Cost Overrun Control during Tunnel Construction

Cost overrun is common in tunnel projects. During the construction of a tunnel, overrun is mainly related to unpredicted geological conditions as well as prolonged time schedule. The uncertainty of the ground conditions is one of the main features of tunnel design and construction. The main reasons for cost overrun during tunnel construction are analyzed and the measures of controlling cost overrun are presented, with especial reference to the period of tunnel construction. An object-oriented and balanced cost risk system is vital to cost overrun control during tunnel construction under difficult geological conditions.