(1. School of Civil and Architectural Engineering，Shandong University of Technology，Zibo，Shandong 255049，China；2. Key Laboratory for Special Area Highway Engineering of Ministry of Education，Chang'an University，Xi'an，Shaanxi 710054，China；3. School of Transportation and Vehicle Engineering，Shandong University of Technology，Zibo，Shandong 255049，China)
Abstract：Seismic damages of embankment occurred widely in strong earthquakes. It is very important to carry out the probability risk assessment and to put forward a reasonable risk management method to improve the anti-seismic capacity of highway and the capacity of regional damage prevention and mitigation. The seismic damage levels of embankment were classified and the seismic damage parameters were selected. The relationship between the seismic damage levels and seismic damage parameters was established. The embankment at K1125+470 of the expressway of Xi?an to Baoji was studied with the seismic hazard assessment to highway based on CPSHA，the seismic fragility assessment on embankment based on IDA and PSDA，and the seismic probability risk assessment on embankment based on the hazard curve. The acceptable risk and the risk management method for embankment seismic damage were put forward. The positive effect of the retaining wall on the anti-seismic performance was verified. The seismic hazard assessment results of Xi'an－Baoji segment in Lianyungang－Huoerguosi expressway is higher than that of the fourth generation seismic zoning map，which is consistent with the reality of seismic activity in Weihe fault basin. When PGA(PGA is peak ground acceleration) reaches 0.6 g，the probability exceeding the severe damage is 65.910%，when PGA reaches 0.8 g，the probability exceeding the severe damage is 99.995%，indicating that the embankment is prone to seismic damage. The risk probability of exceeding the severe damage in the next 50 years is 36.46% and the probability of mainly intact and minor damage is 28.49%. The probability risk being 40% exceeding the severe damage in the next 50 years is regarded as the acceptable. The risk management method is suitable for the anti-seismic design of new embankments and anti-seismic strengthening of existing embankments. In the next 50 years，the probability risk exceeding the severe damage of the embankment with a retaining wall is 15.29% lower than the one without a retaining wall. The probability of mainly intact and minor damage is 15.62% higher than the one without a retaining wall.