KUCHING: Universiti Malaysia Sarawak (UNIMAS) has welcomed the announcement of the federal government’s allocation of RM50 million in the Budget 2023 to embark on a Cup Lump Modified Bitumen (CMB) technology for road maintenance.
“Cup lump rubber is more accessible for road construction than rubber tyres since it does not require extensive processing,” said its Deputy Vice-Chancellor, Research & Innovation Professor Dr Wan Hashim Wan Ibrahim. “Using cup lump rubber in road construction will increase domestic rubber consumption and will greatly reduce the surplus of rubber on the market.”
Speaking to New Sarawak Tribune, he said cup lump rubber is produced when latex is left uncollected and allowed to solidify due to bacterial action. It is typically composed of the dried films and rubber bits discovered in the tapping cups at the beginning of consecutive tapping. Cup lump rubber is widely used as a filler to enhance the performance of roadway surfaces.
“A part of cup lump rubber that has been pre-treated will be combined with bitumen to generate CMB,” explained Wan Hashim.
“Then, a predetermined quantity of CMB will be mixed with aggregates to produce Cup Lump Modified Asphalt (CMA). The potential of CMB to increase the durability, skid resistance, and permanent deformation of road pavements caught the interest of industries involved in road construction. On average, more than four tonnes of cup lumps are used every kilometre of roadway.”
Two layers of CMA are typically used as the surface of the pavement. As the initial layer, a thicker CMA layer is used to add durability and strength to the pavement, allowing it to withstand the weight of heavy vehicle traffic.
The second layer consists of a thin CMA layer that contributes to the needed smooth and level surface for asphalt paving, hence increasing its resistance to the wear and tear caused by automobile traffic.
Wan Hashim also highlighted the use of cup lump rubber to cover cracks and cavities in pavement.
“CMB is placed into the crack or void, heated and compacted until it forms a strong bond with the surrounding asphalt, and then allowed to cool. This contributes to the production of a better seal, preventing more pavement cracking and damage.”
In addition to creating a smoother surface, cup lump rubber also reduces the noise generated by automobile traffic. “This is because the rubber material absorbs a portion of the sound energy, lowering the amount of noise generated by passing automobiles,” said Wan Hashim.
Using cup lump rubber in asphalt pavement construction has substantial environmental benefits as well. “It reduces the volume of cup lump rubber that, if mismanaged, would contribute to waste and pollution,” added Wan Hashim.
The CMB technology is expected to provide an eco-friendly and cost-effective solution for road maintenance in Malaysia while also increasing domestic rubber consumption and improving the livelihoods of Malaysian rubber tappers.
