Up–up construction takes off in Korea

An innovative deep-basement construction technique pioneered in Korea is proving highly beneficial and looks set for adoption worldwide. Experience on over 40 deep-basement building projects shows that it cuts construction times and costs by 15–20% and significantly reduces ground movements and personal injuries. The technique eliminates the need for installing and removing traditional temporary propping systems by using a permanent steel basement framework to support lateral soil loads during excavation. When the excavation and framework reach the bottom, upward construction of the basement and superstructure start simultaneously—hence the description ‘up–up’. This paper describes the first project on which the technique was used and sets out its many advantages over temporary propping systems as well as alternative top–down construction techniques.