Highway to polymer bitumen hits a snag

Infographic: TBS

With no testing facilities or technicians available for checking the quality of imported polymer modified bitumen, the project to repair the Dhaka-Chattogram Highway has remained incomplete three years since it began.

The special variety – polymer modified bitumen (PMB) – will be used for the first time in the country on the highway to make it more durable.

Potholes began appearing on the upgraded four-lane highway, a crown jewel in Bangladesh's development plan built at a cost of Tk3,600 crore – double the initial estimate – only seven months after completing construction in December 2016.

The potholes were blamed on faulty construction techniques and movement of overloaded vehicles.

The potholes meant traffic could not smoothly ply the highway, the key transport point from Chattogram Port.  Renovation works on different parts of this highway began from the mid-2017. But those were not a permanent solution.

In July 2019, a project worth Tk793 crore was undertaken to complete the renovation of the highway by June 2023 by applying the special variety of bitumen on 50 millimetres of the existing surface, without repairing the holes fully.

But as per the rules of the commerce ministry, the quality of imported PMB must be tested in labs before being unloaded.

This is where the problem began.

Importers could not test the bitumen at the labs in BSTI, Buet and Eastern Refinery, as those did not have any equipment to assess the quality of the imports.

Only the Roads and Highways Department had the needed equipment, but they did not have any technicians to conduct the tests.

Against this backdrop, the conditions for importing polymer bitumen were relaxed for six months on 13 February, after which the price of asphalt had increased in the international market.

But why did it take two years to come to this decision?

Suniti Chakma, project manager and executive engineer, Department of Roads and Highways (RHD), Cumilla, said, "The process of tendering and issuing the work order took time. We gave the work order 28 March 2021. Then the import hit the snag as there were no labs," he said, adding Covid-19 also played a role in the delays.

Till date, only 30% of the demand has been met through imports.

On the other hand, contractors are also facing problems removing undulations on the highway which have increased in recent days due to technical faults.

Officials said that a proposal has been made to extend the duration of the project for two years as it would not be possible to complete the repair work within the June deadline next year.

A meeting of the steering committee of the project chaired by Road Transport and Highways Secretary Nazrul Islam on February 23 proposed increasing the term and costs.

Suniti Chakma told The Business Standard, "The complex issue of polymer bitumen import was not discussed when the project was approved. The idea was to get special support from the government for importing PMB.

"The PMB is being used experimentally on the Dhaka-Chattogram highway for the first time in Bangladesh. Due to the mixing of plastic with bitumen, it does not melt even at high temperatures. This makes the road sustainable.

"It was also thought that labs can be easily set up at the BSTI, Buet and Eastern Refinery for testing bitumen. But these institutions could not set up such labs," he added.

Meanwhile, the three bodies mentioned in the commerce ministry circular say that while they were expected to set up the labs, they weren't given any directives.

Md Lokman, managing director of the Eastern Refinery Ltd, said that they had no plans to set up a lab for PMB testing as there was no directive from the authorities in this regard.

Mohammad Monir Hossain Howlader, deputy director of the commerce ministry who signed the six-month import relaxation notice, said they were aware that Buet was going to conduct the tests, but Eastern Refinery couldn't at the time.

"We gave them six months' time. We want them to set up the labs as fast as possible, but they need to have the budget, manpower and experts for it. It cannot be rushed. We hope it will be done soon and we will give them the time they need to do so," he said.

Rafiqul Islam, instructor, Transport Engineering Lab, Buet, said, "We test general bitumen here in Buet lab. We do not have the equipment to test PMB. However, there are plans to modernise the lab."

He added there were plans to set up a lab by next year and this was in their internal budget.

Waliur Rahman, additional chief engineer, RHD, said that PMB roads were becoming popular in different countries of the world as it ensured that roads don't melt at high temperatures.

He said PMB, which was resistant to rut, was being used on all major highways, including the expressway in India.

The use of PMB also has environmental benefits.

Head of the environment sciences department at Stamford University Professor Ahmed Kamruzzaman Majumder said that there are three types of benefits of PMB. As it is made with recycled plastic, it plays an important role in safeguarding the environment.

Furthermore, it creates employment opportunities for those who collect plastic, while it is possible to build a sustainable communication system through its use, he said.

Higher price of polymer bitumen

Around 28,000 tonnes of polymer bitumen would be needed for the 192.3km road from Daudkandi to Chattogram on the Dhaka-Chattogram highway. So far, only 8,500 tonnes have been imported after the relaxation of government conditions.

People concerned said testing of imported PMB may become mandatory again after mid-August, which could further hamper the implementation of the project.

SM Mumtaz Uddin, director of Spectra Engineers which is the contractor for 125.9km of the road on the Cumilla section, said, "We have to import PMB at a much higher price now as it could not be done on time. The cost per tonne of bitumen from Dubai has increased by 40%. If the extra price is not adjusted with the construction cost, we face a loss."

He said, "We have to import 18,000 tonnes of polymer bitumen for the Cumilla section of the highway. So far, only 7,000 tonnes have been imported. Meanwhile, once the import conditions are changed, getting PMB will become complicated again."

An official of the RHD, on condition of anonymity, said 10,000 tonnes of PMB is required for six kilometres of the Chattogram part. Only 1,500 tonnes have been imported so far.

Unplanned project proposal

Issues with the bitumen import is only one part of the story.

Undulations and ruts on the highway have also increased due to the lack of repairs, but the purchase of materials needed to fix those were not included in the project proposal.

A proposal in this regard has been placed to amend the project proposal to include the items needed to repair the undulations, which would increase both cost and duration of the project.

Suniti Chakma, the project manager, said, "We could not assess the issue of undulation during the preparation of the project proposal. Now we have to measure the amount of undulation before buying the construction material and amend the proposal accordingly."

Pintu Chakma, executive engineer, RHD, Chattogram, said, "The Chattogram section has rutting on a 48 km stretch which cannot be cut and levelled with a machine. But we have seen that undulations still remain after removing the rutting. If the repairs are done without solving this problem, the project would bring no success."

Until the problems are solved, commuters, along with businesses, will continue to suffer.

Bangladesh Truck-Covered Van Owners Association General Secretary Rustam Ali Khan said the Dhaka-Chittagong was not of international standard and potholes appeared within days of upgrading the highway to four lanes.

The holes damaged vehicles and led to gridlocks, eventually leading to losses for businesses.

He said that although repair works were taken up, no work was being done. "The busiest highway in the country should have been repaired on time," he said.

Mohammad Hatem, executive president of the Bangladesh Knitwear Manufacturers and Exporters Association, said the highway needs to be repaired day by day. If not, congestion will increase and increased traffic on such an important highway affects imports and exports.

Amirul Huq, former director of the Bangladesh Chambers of Commerce & Industries and also the Chittagong Chamber, echoed these views.

"The state of the highways has increased the sufferings of people and the cost of doing business. This is sheer negligence from the authority," he said.

PMB getting popular in road tech

Polymer modified bitumen, a mix of bitumen and polymer, has been in use for road construction for its extra strength, additional elasticity, high resistance to deformations, heat and frost, according to studies by global civil engineering firms, including those in India, Pakistan and Sri Lanka.

Roads made from PMB can save up to 32% in maintenance cost during a 12-year cycle of operation, says a report of Gazprom of Russia, which is a major supplier of PMB to Europe, South America and Asia.

Increasing traffic volumes, vehicle loads and tyre pressures cause accelerated degradation of roads and PMB has become a popular option in road technology for at least three decades to reduce rutting, cracking and stripping, and to make highways last longer with lower maintenance.

Still a small one, the global PMB market is expected to grow at 4.4% over the next five years, to cross $10.6 billion in 2024, according to data released by market research firm, MarketWatch.

Polymeric bitumen was introduced in road technology in Europe in the 1970s, while its consumption in the US increased in the mid-1980s, according to IntechOpen.

Highway engineers agree that water that enters through cracks and gets trapped adversely affects the roads paved with bitumen, and the problem can be mitigated if polymer is added to bitumen.