Development of Low Noise Road Surfacing on Local Roads in Hong Kong

Hong Kong being one of the most densely populated cities in the world, the large number of residential developments and the very concentrated road network systems make road traffic noise become a concerning environmental issue. While the road traffic noise impacts from the new roads and to the new developments are now reduced significantly through noise planning process, HKSAR government also attempts to alleviate existing road traffic noise impacts by various approaches such as retrofitting noise barriers and paving roads with Low Noise Road Surface (LNRS). The performance of Polymer Modified Friction Course (PMFC) has been found satisfactory for high speed roads; yet, the durability of paving PMFC for local roads is an issue. To explore alternative LNRS materials for local roads, polymer modified stone mastic asphalt (PMSMA) and rubberized asphalts are studied to investigate its noise reduction performance and durability. For concrete road surface, the Next Generation Concrete Surface (NGCS), a type of diamond grinding technology, was also studied to evaluate the technical feasibility of achieving noise reduction in local roads in Hong Kong situation. This paper reviews and presents the experiences and technical findings of the mentioned road surfacing studies and trial projects on local road at present.