To improve construction management in the urban rail-transit,the WBS concept is well exploited by crossing a horizontal breakdown of urban rail-transit construction activities with a vertical breakdown of its technology system,thus a WBS matrix is obtained,which is more complete and useful than the WBS tree.This article firstly stated the concepts of interface and WBS matrix,with urban rail-transit analysis of how to use WBS matrix to improve interface management.The composition,structure system and princip...