Study on Structural Scheme of Approach Slab at Roadbed-bridge Transition Section of Slab Track

According to the structure characters of approach slab at roadbed-bridge transition section of slab track,four structural schemes of approach slab are given,and a finite element model of approach slab is established.The mechanics of slab track corresponding to each approach slab scheme is analyzed and compared between them,and the optimal scheme was proposed.In addition,the impact of approach slab unsupported-length on the mechanics of slab track was analyzed.The conclusion can provide the support for the design of roadbed-bridge transition section of slab track.Approach slab can improve the regularities of the track,reduce the types of slab and optimize the mechanics of slab track.However,approach slab position has large impact on the mechanics of slab track.According to the analysis results,the optimal scheme is characterized by approach slab placed on abutment,two ends of the approach slab aligned with the slab edge above,continuous bed pate and rigid foam panel set above the end-near-abutment of approach slab.Besides,the unsupported-length of approach slab has huge impact on the mechanics of slab track and itself,and the design of approach slab and bed plate above should be enhanced.