Planning the construction of a deep basement on the site of a previous retained excavation

The ICD Brookfield Place development in Dubai comprises a 290 m tall tower with a seven-level basement (the deepest in Dubai at the time of construction). A five-level basement, with temporary anchored retaining walls along three sides, was previously constructed on the site along with all the foundation piles for the intended structure. The basement was later backfilled when construction ceased in 2009. The previous basement provided considerable constraints to construction of the new basement. Particular challenges included deepening of the basement, the construction of new deeper temporary retaining walls, pile reuse and construction in close proximity to adjacent structures. This paper describes how the constraints were assessed and how a basement construction strategy was developed to overcome them.