supported by the National Natural Science Foundation of China(Nos.51178101 and 51378112);the Doctoral Program Project of the Ministry of Education(No.20110092110011);the NationalKey Laboratory of Civil Engineering Disaster Prevention of Tongji University(No.SLDRCE08-HZ-02),China
Project supported by the National Natural Science Foundation of China(Nos.51178101 and 51378112);the Doctoral Program Project of the Ministry of Education(No.20110092110011);the National Key Laboratory of Civil Engineering Disaster Prevention of Tongji University(No.SLDRCE08-HZ-02),China