Chengdu-Chongqing High Speed Railway Jialing River Bridge,Originally, there was only one kind of high-speed EMU for Chengdu-Chongqing high-speed railway, CRH380D. With the increase of passenger flow in Chengdu-Chongqing high-speed railway, Chengdu Railway Bureau connected the CRH 3 type high-speed EMU transferred from Beijing Railway Bureau in order to alleviate the passenger flow demand.