JIANG Li-zhong1,LONG Wei-guo1,2,YU Zhi-wu1 ,CHEN Ling-kun1 ,LI Li3
(1. School of Civil Engineering and Architecture, Central South Univ, Changsha,Hunan410075,China;2. School of Mathematics and Physics, Univ of South China,Hengyang,Hunan421001,China;3. The Third Railway Survey and Design Institute Group Corporation,Tianjing300142,China)