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Research on the Purification Ability of Porous Asphalt Pavement to Runoff Pollution

PAP has widely used in Europe, the U.S, and Japan. As an effective technology for urban stormwater management, PAP not only decreases stormwater volumes but also improves runoff water quality including heavy metals, suspended solids (SS) and nutrients. In addition, it help protects groundwater and urban environment. In this paper the current trends of investigating the purification ability of PAP are introduced. The characteristics, the pavement structures and materials are analyzed. The recent researches in field studies and laboratory experiments are highlighted. The present applications of and challenges to PAP are discussed. Further research needs are recommended.