Insights into the design of the two-phase deliver model in the design phase of infrastructure projects

Abstract

Currently, the infrastructure industry is in transformation and moving towards new project delivery approaches. Aiming to improve the predictability of projects and due to a growing desire for collaboration between clients and contractors, the two-phase model has made its entrance in the industry and has been gaining popularity.
During the first phase of the two-phase model, client and contractor work together on the design. The first phase results in a detailed design including the price for execution. After a successful first phase, client and contractor come to an agreement for the execution phase. The price determination of the execution costs is delayed until after the first phase. The contractor therefore has a better grasp of the project risks and is in a better position to offer a more reliable price. The two-phase model is relatively new on the market and therefore has not yet been standardized. The elements of a two-phase model have not been identified scientifically. This research contributes to making reasoned choices on how the elements of a two-phase model can be operationalized in infrastructure projects in a way that the two-phase model contributes to achieving the project's objectives.
The main research question of this study is: What is the optimal operationalization of elements in designing the first phase of the two-phase model in infrastructure projects?