Settlement characteristics and calculation of bending moment for large-area thick raft foundation under tall buildings

Under similar geological conditions, the settlement of integrated tall building with large area raft is more greatly reduced than that of single tall building with similar size and loading. Compared to that of the single tall building at later period after completion, the settlement of the integrated tall building is smaller, generally less than 20% of the total amount. The settlement of the integrated tall building usually becomes stable about one year after its completion. When the integral flexure of plate-raft foundation is no more than 0.02% and the crack resistance of raft foundation is no less than 2, only the local bending moment should be taken into consideration in the design of plate-raft foundation, and the integral bending moment is ensured through structural measures. When the integral flexure of plate-raft foundation is more than 0.02% or the crack resistance of raft foundation is less than 2, the effects of the local and integral bending moments should be considered.