In order to provide a theoretical basis for running speed-up trains on single-track railways
in China, an analysis is made of the influence of running speed-up trains on the carrying capacity on
speed-up single-track lines. A calculating model for speed-up trains coefficient of deduction is
developed. Through numeric analysis and simulation, an important conclusion is drawn out that the
passenger trains coefficient of deduction on single-track lines decreases with the increase of running
speed. Through analysis of the relationship between the numbers of passing and overtaking
behaviors of speed-up trains on single-track lines, a reasonable quantity of speed-up trains to run on
single-track lines is worked out, and a general conclusion about the influenceof thequantity and running
speed of the speed-up trains on the travelling speed of freight trains on single-track lines is made.