Low-Cost Maintenanceof old Existing Indian Highways Using Asphalt Recycling Techniques

Abstract

In the present study,an experimental attempt has been made to design andproduce Bituminous Stabilized Material (BSM) and to use it as a road base material for the strengthening of Dewas- Bhopal 4 lane Road, S.H-18, through cold in-place recycling technique using foamed Bitumen. A complete survey was carried out for structural and functional failures. The results from the field and laboratory investigation indicate that the road is structurally sound but functionally failed in maximum stretches.  It was decided to replace the damaged top asphalt layercompletely with a bituminous stabilized material (BSM) as an alternative to the DBM course. Various distressed stretches with first-stage failure were selected for milling purposes.Cores were taken from distressed chainages. Reclaimed asphalt pavement (RAP) material was collected using a miller machine from the longest stretch in the job to enable the mix to be designed based on the 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 guidelines for bitumen stabilized materials, TG2 Second revision, May 2009,and IRC- 37: 2012.The blending of aggregate was done as per the specified grading requirement for Bituminous stabilized material (BSM). Under strict laboratory control, all required tests were performedon the Rap material:Atterberg limits, Procter test for MDD and OMC, and Determination of Hygroscopic moisture content.Properties of foamed bitumen and its half-life were found in the lab, Bituminous Stabilized Material was produced with different percentages of foamed bitumen content which varies from 1.5% to 2.5%. By using the suggestedguidelines, Bituminous stabilized material (BSM)wastested for Indirect Tensile Strength under wet and dry conditions and BSM was produced with the composition of 82% RAP material, 17% Dust, 1% Cement, Bitumen VG-10, 2%, and 6.53% water for optimum control successfully.The Test results obtained classify the mix as BSM1which can be used for the heavy traffic in the road base as an alternative option to the Dense bituminous macadam(DBM) layer.