Truckers overloading their vehicles and getting on Bailey bridges is causing frequent collapse of the temporary structures, some of which are decades old.
Signs near Bailey bridges are there to warn of the dangers of passing with heavy loads. But drivers, especially of trucks, pay little heed to the warnings and often cause the collapse of the bridges, resulting in fatalities and communication disruptions, experts said.
Even though the bridges are temporary, there are Bailey bridges that have been constructed right after the Liberation War but are still being used, sources said.
The Roads and Highways Department (RHD) has no recent data on the number of Bailey bridges in the country or how many of them are vulnerable.
The RHD data of December 2017 shows that there are 4,507 bridges under the department, of which 996 are Bailey bridges. Of them, 973 have steel decks while the rest have wooden decks.
At least two Bailey bridges collapsed in May, bringing the safety issue to the fore.
A decades-old Bailey bridge caved in on May 11 in Santosh area of Tangail Sadar when a truck with an overload of sand was crossing it. This snapped road communication between the district headquarters and five unions.
On May 18, a part of the deck of a Bailey bridge over the Langulia river in Nakachhim of Tangail’s Basail upazila collapsed, disconnecting Basanal and Sakhipur upazilas from the district town.
The RHD is now in the process of collecting data on bridges and would learn about the “health of the major bridges” early next year.
However, a preparatory survey of the RHD’s “Western Bangladesh Bridges Improvement Project” in 2015 said most of the Bailey bridges were in an “unsafe condition”.
It had said the conditions of the bridges deteriorated and, in some cases, the bridges had collapsed.
These bridges have thin steel or wooden decks, which get easily damaged by repeated use by heavily loaded vehicles. Due to insufficient repairs, many have been left in hazardous states, the survey reported.
Khurshid Alam, executive engineer of Bridge Construction and Management Division-1, said the Bailey bridges were built on temporary basis and with a standard load capacity of 7.50 tonnes.
“But overloaded vehicles are making them vulnerable,” he told this correspondent.
He said they put up warning signs near almost all the Bailey bridges about their load capacity, but a very few drivers abide by it.
After an accident, the RHD usually files a case against the owners of the overloaded vehicle, he added.
Asked about the absence of recent data on bridges, Rowshan Ara Khanam, additional chief engineer (bridge management wing) of the RHD, said they were collecting relevant data.
She said they have developed a software and provided training to some officials under the Bridge Management Capacity Development Project to create a database for bridges.
They have started collecting data in January and hope to get the information on major bridges within January next, she added. “The information will help them set maintenance priorities,” she added.
“Besides, we are gradually replacing all Bailey bridges with RCC/PC bridges [concrete bridges],” Rowshan Ara said. But she could not say when all of them would be replaced.
Transport expert Prof Shamsul Hoque said the root cause behind the collapse of Bailey bridges is the overloading of vehicles.
“In my assessment, one Bailey bridge collapses every month on an average,” he told this newspaper on May 19.
Besides, overloading also damages concrete bridges and roads and reduce their durability and ultimately increase maintenance cost.
Prof Shamsul, also the former director of Accident Research Institute at Buet, said modifications made to vehicles, especially trucks, create more scope for overloading.
Even though such modifications are illegal, those vehicles get their annual fitness certificate from the Bangladesh Road Transport Authority, he said.
The expert said the authorities have to stop issuing the fitness clearance to modified vehicles to stop overloading and save infrastructure and government money.
Setting up weigh scales on highways would not be viable, he said.
A trucker, wishing not to be named, said drivers hardly ever look at the warning signs placed before Bailey bridges. He said their job is to drive and they care little about the load unless it is to an extent that it damages the vehicle.