ABSTRACT
The bearing capacity of a raft-pile foundation under cyclic loading depends on the conditions of joint deformation of the soil, piles and pile cap, their strength and deformation properties and corresponds to the maximum cycle load that a raft-pile foundation can perceive with a given number of loading cycles and a predetermined maximum settlement. The maximum bearing capacity under cyclic loading is determined for the stage when tangential stresses along the lateral surface are absent in the upper and middle parts of the piles due to the achievement of the maximum shear resistance. It is assumed that a spatial stress-stain state is realized in the soil under the raft and under the pile toe. The bearing capacity of the raft-pile foundation is reached when the stresses under the pile toe and under the raft exceed the fatigue strength and the ultimate deformations of the soil under triaxial cyclic compression. The objective of study is to determine ultimate bearing capacity of the raft-pile foundation under cyclic loading. Theoretical studies have been carried out, the redistribution of efforts between the main elements of the raft-pile foundation has been considered. The change in the stress-strain state of the base of the raft-pile foundation under cyclic loading is considered. The significance of the obtained results for the construction industry lies in the fact that the proposed method for the first time allows us to evaluate the bearing capacity of a raft-pile foundation. Comparison of the calculation results for the proposed model with experimental studies showed good convergence.
