The performance of pavement preservation is significantly affected by climate conditions, as mentioned in the literature review. However, no sole material can completely fulfill the criteria of performance as flexible pavement in a variety of environments. Moreover that, with the changes of the times, some innovative pavement materials are invented and adopted in other countries which might be can adopted in Hong Kong. As a result, a review on flexible pavement preservation materials selection is required.
Although the Research and Development Division of the Highways Department provides technical assistance for government engineers, the instruction for choosing materials for preservation measures of flexible pavement is not disclosed and verified in the public documents uploaded by Highways Department, which will be confused for the public, even including the Contractor.
According to Tezera, the unique characteristics of different stakeholders, as well as their interactions with other determinants, make them essential to the implementation process. It is vital that the feedbacks and voice from different stakeholders in the society can be taken into consideration for the establishment of a successful policy or strategy as supports from public is essential for every successful policy or strategy indispensably. Therefore, to suit the development of city with rapid business activities, the flexible pavement preservation strategy should seek public consultation and be updated on a regular basis for future traffic development in Hong Kong.
To gain a comprehensive picture of the flexible pavement preservation strategy in Hong Kong, the following questions need to be addressed or investigated.
First of all, the design approaches and concepts of flexible pavements have been evolved over the past decades. For the purpose of designing an effective flexible pavement preservation strategy, understanding the origins of the development of flexible pavement is essential. So, the evolution of flexible pavement design theory approaches and concepts will be analyzed from past to present for the development of flexible pavement strategy.
Moreover, views from different parties are crucial for strategic planning since they involve different stakeholders. Hence, the incentives like economic issues and social factors related to implementing flexible pavement preservation will be discussed to explore the relationship between the development of flexible pavement strategy and stakeholders.
Besides that, pavement preservation strategies are various worldwide based on the difference of diverse factors, such as climate, culture and types of the car passing by. Therefore, the relevant factors that affect the overall performance of flexible pavement strategy will be studied to strengthen the preservation strategy's pertinence. Meanwhile, the existing flexible pavement preservation strategy adopted in Hong Kong will be reviewed and compared with other countries to evaluate its efficiency.
Last but not least, the requirements of materials selection for flexible pavement will be investigated since the instruction for the selection of materials of flexible pavement is not revealed or clearly stated in the documents issued by the Highways Department of Hong Kong.