Concrete road : A hope for a durable solution in highway

Gulam Rabbani :
Bangladesh is a rainy country where rainfall sustains for about five to six months in a year. Besides, high temperature also prevails here throughout a large portion of the year. Since bitumen is sensitive to water and heat, most of the roads made with bituminous by the Roads and Highways Department (RHD) become damaged easily. As a result, the authorities concerned of the government are hoping for a durable solution to this problem by constructing concrete roads.
Government is constructing about 60 kilometers road with concrete matters from Bogura’s Mokamtola to Rangpur under its ‘SASEC Road Connectivity Project-2’. Under this project 190km highway will be expanded into four-lane from Elenga of Tangail to Rangpur. The highway has also service lanes.
Construction of such a large portion of highway with concrete pavement is also new in the country, where flexible pavement using bitumen is common. The project authorities said taking the climate nature of Bangladesh into consideration where rainy reason is relatively longer, concrete pavement is more durable and cost effective.
The Roads and Highways Department is implementing the project including land acquisitions at a cost of Tk 18,600 crore, with loan from Asian Development Bank. The project deadline is December 2024.
In Bangladesh, flexible pavement is being constructed on almost all roads. But lately, concrete pavement
or rigid pavement is being built on some parts of highways, especially in market and toll plaza areas and the places prone to water-logging.
Santosh Kumar Roy, Additional Project Director, said they decided to construct concrete pavement keeping various benefits in mind.
He said Bangladesh experiences rainfall for five to six months a year while temperature relatively remains high during the summer. But bitumen is vulnerable to water and heat, Santosh said, adding that overloaded vehicles cause serious damage to bituminous pavement.
He further said, “Although the design life span, the life expectancy of a structure, for bituminous road is 10 to 15 years, it has to be repaired every two-three year after the construction due to water-logging, plying of overloaded vehicles and some other reasons, which need a huge amount of money. On the other hand, the design life span of concrete pavement is 20 to 25 years and its maintenance cost is very minimal.”
The construction cost of concrete pavement is 10 to 15 percent higher than that of bituminous pavement, but the total life cycle cost of concrete pavement is 50 percent lower than the bituminous pavement due to nominal maintenance cost, said the official.
He added that except stone, materials used for concrete pavement are available in the country and that’s why concrete pavement is helpful in context of the current US dollar crisis.
During a recent visit it was seen that the authorities of the RHD project is using the state-of-the-art technology for the first time in the country to construct concrete pavement. Construction of concrete pavement in a major portion has already been completed.
Santosh said construction of concrete pavement manually causes roughness on the surface, which impacts on the ride quality. But their Chinese contractor is now using automatic concrete-paving machines, which ensure smooth surface, he added.
In response to the question whether road damage can cause tire puncture of the cars and trucks, Project Director Waliur Rahman said, “There is no such possibility. There are scopes to repair the damages which will be done with bitumen lining, and it will be more durable as the basement is stronger.”
Bituminous lining has been used to repair the damages in Bangabandhu Bridge (Jamuna Bridge) over the concrete basement and it is lasting for years, added the official.