Roadways subjected to heavy and frequent traffic with extremes in weather conditions can often experience rutting that compromises the roadway’s integrity. This was the case for the Agra-Gwalior Highway, which connects the northernmost and southernmost tips of India. A trial featuring PGXpand®, a bitumen-friendly polymer additive for asphalt, was the subject of an article featured in the August 2022 issue of AsphaltPro.  

 

PATH India, which spearheaded the trial along with the National Highway Authority of India, noted that rutting had been a primary concern regarding the well-traveled highway. By incorporating PGXpand into their polymer modified bitumen (PMB) mix, the agencies looked to achieve performance specifications that could stand up to heavy and constant traffic conditions in addition to temperatures exceeding 45°C. 

 

Initial preparations included the development of a mix design including PGXpand by PATH India and an independent research facility. “PGXpand has been tested, evaluated, and vetted by leading experts in academia, industry and transportation agencies from around the world,” said Sachin Raje, General Manager, Bitpath. “It has been trusted and effectively used on roadways across the globe since 2015.” With this confidence and a final mix design, the field trial parameters were established and approved.  

 

The PMB mix created for the trial consisted of VG30 grade bitumen and 1.5% PGXpand. The mix was used to pave a 30-mm wear layer on a four-lane-km stretch of the highway. Initial response to the trial, which will undergo additional evaluation by an independent agency, was positive. Speaking of PGXpand, Nakul Agarwal, Project Head, PATH India, noted, “It was hassle-free to manufacture the PMB and the Mix, it was simple to transport the Mix to the site, and the roadway was easy to pave. We are waiting for the post-trial evaluation results and, if everything looks good, we will surely use PGXpand on our other projects.” 

 

Read the full article including the trial details and other unique applications for PGXpand as a polymer additive for asphalt.