Quest for Green Roads

Asphalt batching plant and surface preparation equipment manufacturer, Ammann India, in an interactive session with major stakeholders on sustainable, flexible and eco-friendly pavements, promotes usage of Modern Asphalt Plants. NBM&CW reports.

In a major bid to preserve ecological balance while constructing roads through reduced usage of virgin materials and also to make road projects eco-friendly and cost effective, Ammann India, along with project owners, developers and other stakeholders in road construction, discussed and deliberated new avenues for promoting greener and more sustainable road projects in India, at a one-day event held in New Delhi.

R.K. Pandey, Member Projects NHAI, said, “NHAI has taken up major studies for usage of geogrid to reduce the width of pavements. Design improvisations have accordingly been made. We are also putting emphasis on reducing the total lifecycle costs by bringing changes in the alignment pattern. Perpetual Pavements is being considered as a cheaper option. NHAI has taken up a major initiative towards usage of plastic waste, and tests will be undertaken to gauge the performance of the applied area.” He also expressed his concern that with increasing mechanization in road construction, there is a need for skilling operators in running the machines properly.

Sanjeev Kumar, Chief Engineer, Ministry of Road Transport (MoRTH), said, “The ambitious target of constructing 15,000 kms of National Highways by 2020 will mean a colossal consumption of aggregates, estimated to be about 150 million tons, even though National Highways constitute only two percent of the total road network. Though construction of roads is necessary for a growing economy, it is also necessary to curb exploitation of natural resources and reduce emission of greenhouse gases during construction. To make this happen, it will be essential to recycle and reuse bituminous materials, using milling technologies.”

He informed that MoRTH had issued guidelines on 5 September 2013 on its DPR towards utilization of recycled materials, with a stress on fly ash. The Indian Road Congress had framed guidelines for usage of waste plastic and had identified 350 kms of roads where waste plastic could be used. “With utilization of geo synthetic materials, dependence on virgin aggregates can be largely reduced,” he added.

Dr. Satish Chandra, Director, Central Road Research Institute (CRRI) informed the gathering that with availability of aggregates getting reduced, IRC 37 2018 guidelines stipulates usage of polymer stabilizer mixed with base course materials. To curtail usage of aggregates, it is essential for utilization of hot and cold recycling, especially for road rehabilitation projects.

“CRRI has recently undertaken some critical research on cement grouted bituminous mix (CGBM). The advantage of CGBM is wide as its lifecycle is more than that of bituminous concrete. As part of a case study on the Ranchi-Jamshedpur road, we studied rehabilitation with the use of steel slag and have also conducted some studies on use of ferrochrome, which gives more strength.”


He opined that MoRTH should come out with more trials on sections through use of waste plastic & slag and that CRRI could be a suitable partner in such a venture as Tata Steel had approached CRRI for use of waste slag.

Highlighting Ammann’s India strategy in making greener roads, Dharmesh Mashru, CEO, Plants Division, Ammann India, said, “With Ammann having a global presence and Apollo having a local origin, the joint venture entity is offering a wide range of solutions for road construction in India. Backed by its 150 years of experience, Ammann has the most advanced combustion technology in its asphalt batch mix plants. Since dust is a major issue in the operation of the plants, Ammann offers scavenging systems with advanced bag filters for full coverage of the plants. During recycling, there is a complete exhaust gas treatment in our plants. To curtail dust, Ammann has fully enclosed plants for storage of stockpiles. Under the Make in India initiative, our strategy is to manufacture cost-effective plants in India.”

Peter Maurer, Global Commercial Manager, Ammann India, added, “Since there are issues of getting virgin aggregates in India with consistent levels, it adds up to the cost. RAP is the most viable proposition for processing and heating recycled aggregates. However, for usage of RAP, proper handling and storage of the materials is vital as general crushing will generate fines, which can have a negative impact on the performance of the plants.”

Saurabh Bhargava, Deputy Manager, ICT, Deepak Jotawar, Principal Manager, Stup Consultants, and Shankar Lohani, Associate Director, AECOM India, shared their views on trends in pavement material design. According to them, supervision and a realistic assessment are major challenges while preparing flexible pavements and should be undertaken as per the design.

Sunil Sapru, CEO - Marketing, Ammann India, informed that the company’s research team was working towards utilization of waste plastic in its asphalt batch mix plants. “We will undertake critical value engineering for making the plants adaptable to the new materials and also for safe operation of the plants,” he said.

With respect to the Indian Road Congress’s specifications and standards for asphalt pavements, Secretary General, IRC, said, “To facilitate construction of flexible pavements, IRC had made revisions in the IRC-37 code, in 2012, and in some other codes as well.”


Dr. I.K Pateriya, Director - National Rural Infrastructure Development Agency, informed that to promote green roads, they have been using coir in the construction of roads in Kerala. “Since there are directives from the government for usage of plastic materials, we are looking towards using them in higher volumes. As a major initiative towards curtailment of carbon footprint in road construction, we are emphasizing procurement of local materials at source or in the vicinity of the road construction site to cut down transportation costs as well.”

The session conclude with the delegates and speakers observing that since use of plastic materials is being emphasized by the government, there should be a validation of the materials and they stressed that NHAI should give a mandate to CRRI for guiding the contractors in the use of plastic materials. As Mashru said, “Since usage of waste plastic materials is being focused on during preparation of the bituminous mix, NHAI should set stipulations on the melting points of the materials.”