The Impact Of Extreme Climate On The Asphalt Pavement And Countermeasure In Guangdong Region

With the increasing frequency and intensity of extreme climate，it has causedbigger harm for China road. But extreme climate include many types of climate,it also caused different road damages in different parts. Over the years,Highway workers havea lot of research about the impact of climate on the road,And achieved fruitful results.However, these mostly studies focus on the impact of climate change on the highwaynationwide, not have enough comprehensive and in-depth study on the impact of road weather conditions in the region.This paper research1980-2009years of climate change about four typical areain Guangdong, and detailed analysis the characteristic ofclimatic changeand development; Through the investigation on early damages of theasphalt road surface in Guangdong region, set up the evaluation index of extreme climateaffecting the asphalt pavement and propose the appropriate measures.This papaer surveys the impact of the multiple extreme weather events in southern China on asphalt pavement performance of the current situation, pointing out that extreme weather factors affecting the asphalt pavement performance and pavementdisease, and analyzed their relationships deeply. The study summarizes high temperature and precipitation trends and laws in the Guangdong region during nearly30years; found that the frequency, intensity and duration of the region’s extreme heat andheavy precipitation were tested growth trend. To combine the shortcomings of existing domestic and international construction specifications of the high-temperature indicators in practical engineering application. Proposed a continuous hottest three days andthe average maximum temperature value as the asphalt pavement design for the Guangdong region of high temperature indicators, temperature sequence of97percentilethreshold as extreme heat indicators for the realization of the asphaltpavement of theGuangdong region effectively partition to provide reliable basis. In view of the trend of extreme rainfall and the project requirements, The30-year daily rainfall of97percentile threshold was first proposed as extreme precipitation index and asphalt pa vement design precipitation index in Guangdong area.The paper bases on the frequent, multiple trend of extreme high tempreature and rainfall, proposed using asphalt concrete of high modulus to answer the rutting and water damage caused by extreme high tempreature and rainfall. Selection the AC-13C and AC-20gradation that used as asphalt surfaceand asphalt middle course inGuangdong region，through the static modulus and splitting strength test to determine the best dosage of high-modulus additive of0.6%. Respectively using the ruttingtest, RLWT test and the dynamicmodulus test for the high temperature stability testfor the AC-13C mixture with the additive SBS modified asphalt and the AC-20mixture with the additive and70#asphalt. In addition, the paper build a new method on existingsimulated tests, the moisture stability of AC-13C and AC-20high-modulusasphalt mixture was studied by new simulated tests in the laboratory and outdoor. The result of above experimental show high-modulus asphalt mixture have characterized by well high temperature stability and moisture stability. Itcan be used to meet the challenge by the impact of extreme weather on the asphalt pavement in Guangdong region.