Abstract: The Technical Specification represents a dynamic document, subject to continuous evolution through the ongoing inclusion or exclusion of the latest techniques and technologies over time. This study thoroughly examines the Third Edition of the Roads and Highways Department (RHD) Technical Specification (2016) pertaining to the production and placement of dense bituminous surfacing. The scope of modification is assessed based on current state-of-the-art technologies. Various elements of the existing specification, including minimum and maximum VMA requirements, VFA range, lift thickness, field density measurement system, aggregate gradation, and binder grading, appear to be inappropriate. This study identifies the inadequacies and proposes improvements such as restrictions on natural sand content, the use of hydrated lime, incorporation of the Baily method in aggregate blending, Apparent Film Thickness requirements, Gmm criteria, HMA performance tests, and statistics-based quality acceptance. These enhancements are expected to significantly enhance the assurance of bituminous surfacing performance. Furthermore, introducing a certain level of flexibility in specification requirements related to census and strength properties of aggregates, considering the design traffic environment and layer position, could optimize performance, economics, and sustainability.
Keywords: VMA, VFA, lift thickness, hydrated lime, Baily method and performance test.
Title: RHD TECHNICAL SPECIFICATION FOR DENSE BITUMENOUS SURFACING: A COMPREHENSIVE REVIEW
Author: Nahida Sultana, A H M Javed Hossain Talukdar, Md Joynul Abadin
International Journal of Engineering Research and Reviews
ISSN 2348-697X (Online)
Vol. 11, Issue 4, October 2023 - December 2023
Page No: 75-85
Research Publish Journals
Website: www.researchpublish.com
Published Date: 14-December-2023
