Abstract: The standard system,design procedures,routine practices and other aspects of deep excavations design in Hong Kong SAR (Special Administrative Region) and Macau SAR of China and overseas regions are quite different from those in Mainland China. Based on the design practices of deep excavations in Barra Transportation Hub in Macau SAR,the design of deep excavation support in overseas projects is introduced in detail,including determination of the embedded depth of diaphragm wall,downward extension of diaphragm walls in hard rocks,strut system,structural calculation,verification of stability against overturning,etc. The stipulations of deep excavation design in British Standard and the standard of Hong Kong SAR are compared with those provided in the standards of Mainland China. During desk study,numerical modeling was adopted to calculate the force and deformation of bracing system of excavation; during construction,numerical method was also adopted for back analysis and predictions based on filed monitoring data,which guaranteed smooth construction.

Key words: overseas project, deep excavation, strut system, downward extension of diaphragm wall, numerical modeling, stability against overturning