Reducing the costs for deep foundations of high-rise buildings by advanced numerical modelling

Abstract

When considering foundations for high-rise buildings in urban areas a mayor task is the reduction of settlements and differential settlements of new structures and adjacent buildings to ensure their safety and serviceability. In many cases the soil conditions can lead to deep foundations in order to transfer the high loads of the building into deep soil strata with higher bearing capacities. Compared to traditional piled foundations where building loads are assumed to be transferred to the soil only by piles, the combined piled raft foundation (CPRF) is a rather new approach. A CPRF is consisting of the three bearing elements piles, raft and subsoil. The load share between piles and raft is taken into consideration and the piles can be used up to a load level equal or greater than the bearing capacity of a comparable single pile. This design concept can lead to a considerable cost reduction for foundations of more than 50 % compared to the traditional piled foundation.