KUALA LUMPUR: The Pulau Indah Expressway is one of three roads identified as being severely damaged due to overloading from heavy vehicles plying the roads daily.
The other two roads are Jalan Permatang Pauh in Penang and Jalan Aring 8-Jeneris in Kelantan.
The Works Department said federal roads that require high maintenance are those used in the transportation of minerals, including from quarries and logging areas, covering a total distance of 156.06km.
"Each road is designed based on specific lifespan, and those with low traffic volume such as rural roads have a lifespan of up to 10 years.
"Meanwhile, roads with medium or high traffic volume are designed with a lifespan of 20 years," the department told Harian Metro.
The department said the lifespan of roads could be reduced by half if vehicles exceed at least by 10 per cent of the permissible laden weight.
If the vehicles exceed the allowable payload by 20 per cent, the roads' lifespan would drop to zero, causing them to suffer damages in a short time.
"This means, if the road was designed with a lifespan of 10 years, it could only last five years if it is regularly plied with vehicles with 10 per cent more of the allowed payload."
Repair works on federal roads, involving a total cost of RM3.2 billion and covering a total distance of 3,821km are still pending.
However, the cost could increase up to RM4.3 billion based on the current prices of goods.
The department said road damages are categorised as functional and structural, with the latter requiring a higher cost.
Overloading could cause the structure capacity to deteriorate and this would affect the road's lifespan.
"If maintenance works are not done within the stipulated period, the pavement structure would worsen, resulting in increasing overall maintenance cost."
There are several factors determining the road specifications and bridge load that needs to be studied before the permissible laden weight could be increased.
The Works Department said the maximum payload is set and gazetted in reference to the Weight Restriction Order.
"In general, the permissible laden weight depends on factors including the existing road specifications, namely, the road width and design.
"We have to also look at the road bridge load capacity on the federal and state routes in determining the allowable payload for heavy vehicles."
There are 15 different classes of weight allowed in the country, with a maximum capacity of between 36 and 53 tonnes.
The allowable payload for heavy vehicles must be approved by the cabinet before it is gazetted, by taking into consideration other implications including coordination and enforcement aspects, it said.
The roads in Malaysia cover a total distance of 20,133.152km, as of Dec 31, 2022, according to the department.
"Of the total, a total 2,016.050km of roads, comprising tolled routes, are under the jurisdiction of the Malaysian Highway Authority, while the department is responsible for federal roads covering a total distance of 18,117.102km, including 3,240.335km in Sabah, Sarawak and Labuan.
"State roads with a total distance of 53,962.923km are also under the purview of the department."
The Road Transport Department (RTD) seized 44 heavy vehicles in its operations between Jan 1 and Oct 31, last year.
RTD enforcement senior director Datuk Lokman Jamaan said the vehicles were found ferrying goods between 70 and 140 per cent above the allowable payload.
Of the total, he said, 17 vehicles were seized in Selangor, 11 in Pahang, seven each in Negri Sembilan and Kelantan and two in Perak.
"The vehicles were confiscated under Section 80 of the Land Transport Act 2010," he told Harian Metro.
Lokman said among the common excuses given by the drivers included low wages and that they were merely following instructions by the owners.
"This shows their lack of road safety awareness.
"Vehicles can also be confiscated for other offences including unregistered machines and those without insurance coverage, as well as having foreign drivers without valid driver's license."