Asphalt pavement stability at high-temperature for the Jiangyin bridge in China

Jiangyin Bridge with a main span of 1385 m, located at the lower reaches of Yangtze River in Jiangsu Province, is a broad way across river of two national expressways (Tong Jiang to Sanya; Beijing to Shanghai). According to the natural environment, the asphalt deck pavement of bridge should bear serious heavy traffic loads and bad weather condition without any damage in the working temperature -14℃ to +70℃. Therefore, Guss Asphalt 50 mm of depth, the British pavement technique is adopted and the lake asphalt (TLA) from Trinidad and Tobago, South America is used as asphalt cement, the basalt from China is used as coarse aggregates.Guss asphalt pavement mixture made by rule of British Standard has more excellences, such as better waterproof quality, smaller void ratio, perfect anti fatigue quality and anti brittle fracture at low temperature. But the high temperature stability of the mixture is not so ideal, even if the mixture is made by rule of the extra heavy traffic class H of British Standard, the stability of anti rut is not satisfied with Chinese Standard about expressway asphalt pavement. The main reason is the difference of geographical location between China and England. Four important measures are adopted in research work: ①revise the ratio of mixture, raise the content of TLA; ②reduce the content of soluble asphalt; ③increase the content of main aggregate (6.0 mm~10.0 mm); ④guarantee the ratio of fine dust to asphalt cement.By testing whole indexes of mixture in laboratory, the optimal design of material ratio of mixture is decided, which not only retaines original excellences, but also improves the high temperature stability of asphalt mixture, successfully makes good use of improved foreign technique to build deck pavement of giant bridge in China.