Abstract

Mapping underground constructions is an indispensable task for modern cities in the world and Hồ Chí Minh City is not an exceptional case. Due to the lack of information of underground works constructed before 1975 together with the increase in  new subsurface sites and inconsistent administration in Hồ Chí Minh City, numerous problems and difficulties have been arisen during solving underground issues. This article introduces GPR surveys, which has been applied in checking and defining locations of some underground constructions  (Water sewers and cables) in Hồ Chí Minh City in order to provide the most suitable solution of the above challenging problems. The results of GPR indicated that a lot of underground works are not situated in accordance with the database and  new construction works have not been updated. Our findings contribute to ensure the safety for civil construction works,  metro line No. 2,, for design and construction of new  warer sewers as well as for identification of “flame igniters” in Bình Thạnh District, Hồ Chí Minh City, Việt Nam.