• KEERTHI

There are approximately 5.90 million kilometers of roads in India, with 300,000 kilometers comprising National Highways (NH) and State Highways (SH). As a result of an increase in traffic flow and the ageing of bituminous surfaces, the majority of these road segments are currently under resurfacing, rehabilitation, and upgradation (4/6 laning). Massive amounts of aggregates and asphalt binder are needed for all of these tasks. On the other hand, when current highways are upgraded (4/6 laning), large sections of bituminous pavement are buried to make room for new facilities such as flyovers, vehicular underpasses (VUPs), pedestrian underpasses (PUPs), and more. As bituminous pavement ages, it becomes necessary to mill or remove it before resurfacing or rehabilitation can begin. Reclaimed asphalt pavement (RAP) allows for the possible reuse of old bituminous pavement materials that are buried during up gradation (4/6laning) and milled or removed during resurfacing or rehabilitation. In addition to protecting the environment and reducing construction costs, reusing RAP in pavement construction also decreases the necessity of virgin materials, which helps preserve natural resources for future generations and eliminates waste. Subgrade, granular subbase, base course, and bituminous binder course are the four layers that make up flexible pavement. RAP can be utilized in each of these layers. Subgrade, granular subbase, and base course applications of RAP with reinforcing elements can improve the performance of flexible pavement. Because of its lower unit rates, RAP does not significantly increase the financial advantage when used in subgrade construction. In contrast, bituminous binder course manufacture requires RAP of exceptionally high quality with consistent characteristics. Therefore, the purpose of this research is to investigate the potential use of RAP in the building of Flexible Pavement's granular Subbase and Base course. Mixing RAP with Crushed Stone Aggregates (CSA) and/or stabilizing it with a small percentage of cement improved its California Bearing Capacity Ratio (CBR) and Unconfined Compressive Strength (UCS) value, making it suitable for use in the construction of granular Subbase / Base course of Flexible Pavement. However, untreated RAP was not deemed suitable for this purpose. Pavement alternatives that used stabilized RAP as subbase, consisting of 50% RAP, 50% CSA, and 4% cement, outperformed traditional flexible pavement with granular subbase in terms of predicted pavement life. iv The findings of the model experiments show that when compared to unreinforced WMM materials laid over a soft marine clay bed, the load settlement characteristics of RAP and mixtures of RAP and Wet Mix Macadam (WMM) reinforced with Polymer geogrid, Polymer geocells, Bamboo geogrid, and Bamboo geocell are superior. So, instead of using traditional WMM foundation materials for Flexible Pavement construction, you can utilize polymer-reinforced aggregate (RAP) or a blend of RAP and WMM (50:50). Bamboo geogrid and bamboo geocell are reinforcing materials that are treated with bitumen emulsion to make them more durable. In contrast, polymer reinforcements are not biodegradable. When compared to traditional flexible pavement with granular subbase, alternative pavement choices using stabilized RAP as subbase are approximately 36% more cost effective, according to market- based cost analyses. Similarly, when compared to traditional flexible pavement with granular subbase, the use of polymer/bamboo geogrid and geocell reinforced RAP as subbase had the potential to reduce costs by around 11.50%.

SUB BASE

"ANALYSIS ON THE STABILIZATION OF SUBGRADE SOIL USING RECLAIMED ASPHALT PAVEMENT", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.11, Issue 7, page no.h724-h749, July-2024, Available :http://www.jetir.org/papers/JETIR2407781.pdf

"ANALYSIS ON THE STABILIZATION OF SUBGRADE SOIL USING RECLAIMED ASPHALT PAVEMENT", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.11, Issue 7, page no. pph724-h749, July-2024, Available at : http://www.jetir.org/papers/JETIR2407781.pdf