Field Construction and Investigation on Asphalt-Rubber Gap-Graded (AR-Gap) Pavements Placed on Highways in India

Description

Field Construction and Investigation on Asphalt-Rubber Gap-Graded (AR-Gap) Pavements Placed on Highways in India

Veena Venudharan, Ashish Kumar, Krishna Prapoorna Biligiri, Ujjwal Kumar Mukherjee

ABSTRACT: Over the past few decades, researchers have observed that CR modifiers could be successfully engineered with unconventional aggregate skeleton by using gap and/or open-graded gradation due to the presence of extra space available in the aggregate matrix for accommodating CR particles. Though several laboratory and few field investigations have proven that gap graded CR mixtures are successful in outperforming conventional ones, there is still a need to further investigate the modified mixtures for their field performance. Thus, the objective of the study was to construct AR-Gap mixtures based on laboratory customized product developed by the authors and to investigate the various aspects during the field construction of those AR-Gap mixtures. The scope of the study included: construction of the AR-Gap mixtures based on the laboratory studies, cost analysis of AR-Gap pavement test sections, and field visual performance evaluation of test sections. The study concluded that AR-Gap mixture with higher binder content (additional 1%) is a promising paving material that could enhance field performance without any significant increase in the cost of the pavement system compared to conventional ones. Overall, it is envisioned that this study will provide an essential understanding towards the field construction and performance of AR-Gap mixtures.

KEYWORDS: AR-Gap construction, Asphalt-rubber, gap aggregate gradation, field test section, cost analysis, visual inspection