In order to clarify the collapse mode of multi-span simply-supported beam bridges of high-speed railway， a 10-span high speed railway simply-supported beam bridge in northwest China is taken as the actual engineering background. Combined with the characteristics of double block ballastless track structure on the bridge， the track-bridge integration research model is established. The collapse mode of this kind of ballastless track bridge in high intensity earthquake zone is studied by using explicit integral meth od and energy method. The results show that the key parts of the destruction of high-speed railway multi-span simply-supported beam bridge mainly concentrate on the track area of the bridge expansion joint， the concrete area of the support and the support con tact surface， and the bottom area of the pier. The energy ratio of the 10-span high-speed railway simply-supported beam bridge col lapse discrimination is 89.33%. By coupling the track plate and the groove section at the bridge expansion joint to optimize the struc tural system， the integrity of the track and bridge connection is improved， so that the track at the bridge expansion joint avoids be coming the key part of the destruction at the early stage of the earthquake. The collapse time of structural system is prolonged by about 45%， and the probability of the beam falling is reduced， so that the overall collapse resistance ability of the bridge is improved.