This paper briefly describes the Extended Design Domain concept (EDD) that has been developed by the Queensland Department of Main Roads for road restoration projects. The paper then examines about three years experience with using EDD in Main Roads. The EDD concept was developed initially to address the sight distance issue with road restoration projects. Namely, the existing alignment is retained yet the available sight distance at some places on the road is less than the minimum given in current design guides for the future operating conditions. Furthermore, development of the EDD concept addressed the issue of potential liability for road authorities within the context set by the joint judgement in the Brodie High Court decision of 2001. Besides giving some examples that demonstrate the benefits of using the EDD concept, the paper specifically addresses the issues of design experience and documentation importance. (a) For the covering entry of this conference, please see ITRD abstract no. 0612AR242E.
Abstract