English：

In order to ensure the comfort of subway operation, taking the prefabricated slab track projectof Shenzhen Metro Line 16 as an example, a series of adjustment and optimization processes were carriedout based on the railway track quality index ( TQI ), and a relatively complete technical system ofparameter standard, data acquisition, analysis and optimization adjustment was established, whichsignificantly improves the smoothness of seamless lines in the section after rail welding, and effectivelysolves the technical problems of overall track irregularity caused by laying prefabricated track plates and25m standard track banks in subway track engineering. Combined with engineering examples, the keyand difficult problems of the application of TQI in the construction of urban rail transit structure areanalyzed.