The Austroads Road Design Task Force (RDTF) identified that in Australia and New Zealand the road design process and resulting design solution appears to be predominantly driven by design and construction cost. The notion that a design is governed by cost is also found to vary by contract type and the phases of design included in each contract. The RDTF has indicated that there is a general perception that a design is considered compliant, safe and efficient, if the design process follows and adheres to the relevant guides and standards. This results in less emphasis on constructability, appearance of the road, how it will operate, incorporation of Safe System principles, application of value engineering, and analysis of the resulting whole-of-life costs for the design life. It appears that the concept of sound, robust engineering thinking and judgement has become a ‘lost art’. The current design approach and way of thinking tend to minimise option development and analysis, risk identification and mitigation, and can minimise innovation. Proper design methodology and processes have a high potential to reduce whole-of-life costs. Whole-of-life cost savings are likely to significantly offset additional costs incurred from a more thorough design process. Proper design methodology and process should ensure that the design objective is achieved, whilst also achieving a balance of the objectives of road design. The purpose of this project was to identify the possible reasons that contribute to the fundamental objectives of road design not being achieved. It sought to detect where the existing technical and design process guidance can be improved to provide designers with the information and guidance to apply robust engineering judgment, apply value engineering, apply Safe System principles, and assess whole-of-life costs, whilst also achieving the fundamental objectives of road design. The project concluded that the design guidance in Australia is technically sound including on context-sensitive design and the use of design values within the design domain. The guidance, however, does not adequately inform a designer how to achieve the objectives of road design while balancing competing project objectives, or be cost-effective while considering value engineering and whole-of-life costs (of all engineering disciplines and stakeholders), this includes guidance on how to evaluate a design to determine if the objectives of road design have been achieved. It was identified that if there is to be an improvement in achieving the objectives of road design in the final design solution, designers and practitioners should be further educated as to what the objectives of road design are, why it is important to achieve them, and how to achieve them. Improvements in education are required in conjunction with providing additional guidance for design development and evaluation. Evaluation tools should also be provided, particularly to encourage the development and evaluation of multiple design solutions. A further adaptation of a number of existing design practices have been identified to potentially contribute to the objectives of road design being achieved. In addition, a Definition of Road Design and Road Design Principles was developed to provide a foundation for design philosophy, providing guidance for designers to develop a solution within the project constraints that also meets the objectives of road design. The definition and principles should be integrated with the Austroads Guide to Road Design, so they can be referenced within design tenders, briefs and contracts. Consideration should also be given to legislating that a design solution is required to demonstrate that it achieves the objectives of road design, including being cost-effective, provides value engineering and demonstrates acceptable whole-of-life costs. (Author/publisher)
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