Preservation of Indian National Highways Using Asphalt Recycling Techniques

Abstract

 Pavement preservation using reclaimed asphalting techniques is a new field of research which has not yet been explored in India to a great length and valid guidelines and specification are still not established with available road maintenance norms. A rigorous literature review has been made in this regards to explore an additional method of rehabilitation for maintaining a great Indian road network through asphalt recycling techniques and to understand its cost effectiveness and mix design philosophy. In the present study an attempt has been made to strengthening Chennai-Tada Road, N.H-5, by milling of the damaged bituminous layer through cold planning and cold in- place recycling technique using foamed Bitumen in chainage from 22+000 to 54+300. Various distressed stretches with first stage failure were selected. Cores were taken from distressed chainages. Reclaimed asphalt pavement (RAP) material was collected using miller machine from the longest stretch in the job to enable the mix to be designed based on representative of the site condition. Proper evaluation of the RAP and mix design was undertaken based on the guidelines of Wirtgen Cold Recycling Technology, Technical guideline for bitumen stabilized materials, TG2 Second revision, May 2009 and IRC- 37: 2012. Blending of aggregate was done as per the specified grading requirement for Bituminous stabilized material (BSM). Under strict laboratory control, all required tests were performed on specimen prepared with Rap material for the road base, with different percentage of foamed bitumen content which varies from 1.5% to 2.5%. Using suggested guidelines, Bituminous stabilized material (BSM) was successfully produced with composition of 82% RAP material, 17% Dust, 1% Cement, Bitumen VG-10, 2% and 6.53% water for optimum control.  The Test results obtained classifies the mix as BSM1which can be used for the heavily traffic in the road base as an alternative option to Dense bituminous macadam (DBM) layer.