Abstract:Based on four forms of shared path route, a multi objective non linear mixed integer programming (MIP) optimization model of calculating the number of transit unit(TU) with separate or shared using mode is presented. A calculation software tool based on this model is developed and a case is proposed to testify the availability and validity of the model. The results show that the number of TU affected by five key factors such as headway of shared path sections, number of trains in different routes, running time of routes, layover time in terminals and the using mode (separate or shared) of TU. The practical application of the model to urban rail transit train plan maker (TPM) and its prospects are introduced finally.