Evolution of Non-standard Bituminous Mix—A Study on Indian Specification

Abstract

In India, the aggregate gradation of bituminous mixes and acceptable limits of mix design parameters have evolved through experience in construction and performance. Emphasis, generally, is on the maximum attainable density and strength parameters. However, in view of the fact that pavement failure due to fatigue cracking is predominantly observed in bituminous roads in India, it is necessary to develop or revise suitable specifications for bituminous mixes so that the mixes have high fatigue strength while satisfying the Marshall stability requirement. The present work reports a comparative study of the engineering parameters of various bituminous mixes with aggregate gradations that are different from those recommended in the Ministry of Surface Transport (MOST) specifications for bituminous concrete (BC). New mix specifications for BC have been proposed in this paper, which showed better performance than the conventional gradation without compromising with the Marshall stability and other mix volumetric requirements. A model table is presented to show the economy in terms of reduction of design thickness of pavement compared to the conventional BC mix.

Keywords:

• Bituminous mix
• Mix design
• Marshall method
• Non-standard gradation
• Fatigue performance

Notes

^†Email: [email protected]

Additional information

Notes on contributors

B.B. Pandey †

†Email: [email protected]