Innovative delivery models attempt to deliver major construction projects within budget and on time. However, proving their efficiency is difficult because of a missing base for comparing innovative and traditional delivery models. Therefore, a common ground is mandatory, as given in the “Gemeinschaftskraftwerk Inn” (GKI). Part of the GKI is a 23.5 km long headrace tunnel. The excavations started in the design-bid-build model with a unit price contract, which was terminated during construction by mutual agreement. The alliance contract was chosen to continue the tunnel advance with a new contractor. Only key personnel was exchanged. That allows a unique direct comparison of both delivery models. A probabilistic analysis was conducted. In principle, probabilistic models of the excavations were introduced to compare the construction time in the two different contract models. The key finding is that the construction time is 15 % to 22 % faster using the alliance delivery model.     «

Innovative delivery models attempt to deliver major construction projects within budget and on time. However, proving their efficiency is difficult because of a missing base for comparing innovative and traditional delivery models. Therefore, a common ground is mandatory, as given in the “Gemeinschaftskraftwerk Inn” (GKI). Part of the GKI is a 23.5 km long headrace tunnel. The excavations started in the design-bid-build model with a unit price contract, which was terminated during...    »