Value Engineering to achieve resilience in pavement – Disaster Recovery Project (DRFA)

Abstract

These abstract outlines a comprehensive approach to road rehabilitation in Condamine flood plains, specifically addressing the challenges posed by rain damage and the unique characteristics of black soil subgrade & its behaviour due to long term inundation and its consequences on the pavement. The study employs the principles of value engineering, emphasizing sustainability through the innovative use of existing materials via pulverizing and achieving resilient product. The Condamine flood plains present a complex environment for road infrastructure. During the 2022 rain event, Bowenville Norwin Road located outside town of Bowenville in Darling Downs was significantly affected and had extensive damage due to severe rainfall. As part of the Disaster Recovery works (DRFA) a section of road (10 kms) needed full rehabilitation as 90% of the section being significantly damage, as opposed to isolated pavement repairs. The team at TMR Darling Down integrated value engineering methodologies to optimize cost-effectiveness and environmental impact, offering a sustainable solution tailored to the region's specific challenges rather than traditional approach of “like for like” as stipulated under DRFA guidelines. One key focus is the incorporation of black soil subgrade, a prevalent soil type in the area. Through thorough analysis and engineering techniques, the investigation proposed strategies to enhance the subgrade's stability and resilience to rain-induced damage. Value engineering principles guide decision-making to ensure that interventions not only address immediate concerns of pavement damage but also contribute to the long-term durability of the road infrastructure by addressing the highly reactive black soil, which was affected by over 9 months of rain events. A central aspect of the proposed approach involves the use of existing materials through pulverization & stabilising the subgrade/subbase. By recycling and reusing the existing road material, the project aims to minimize the environmental footprint associated with traditional rehabilitation methods that often involve extensive resource extraction and transportation. By use of existing material, the project also tries to address other requirements of traffic management during construction and reducing the impact on local community due to disruption or road closures. The project also aims to provide “Value for Money” and a viable treatment required for site conditions rather than traditional “like for like” replacement of pavement under Disaster relief funding. Pulverization & stabilization combined serves as a sustainable alternative, promoting circular economy principles and reducing the demand for new raw materials. The project team explored the technical aspects of the pulverization process, considering factors such as material composition, particle size distribution, and compaction. The findings demonstrate that this approach not only contributes to environmental sustainability but also offers significant cost savings compared to traditional methods. In conclusion, the integration of value engineering principles, coupled with the innovative use of existing materials through pulverization, provides a holistic and sustainable solution for road rehabilitation in Condamine flood plains with black soil subgrade. This approach not only addresses the immediate challenges posed by rain damage but also aligns with broader environmental and economic goals, making it a valuable contribution to the field of civil engineering and infrastructure development.