Long-term settlement of pile foundation of bridges based on generalized shear displacement method

Based on the deformation characteristics of pile group foundation of bridges, the interaction system is divided into three parts, pile cap, piles and soil. It assumes the compatibility of stress and deformation on the interface between the piles and the soil which present linear viscoelastic characteristics. Through the analysis of typical elements and the application of elastic-viscoelastic correspondence principle, a formula on pile settlement in Laplace transform domain is derived. After that, the numerical solution in time domain is derived by using the Schapery numerical inversion method of the Laplace transform. It is demonstrated that the solutions of pile settlement are in accordance with those of the finite element method. So the proposed method is rational and practicable. Based on the interaction coefficient which considers the “reinforcing effect” (owing to the presence of piles), the linear superposition of single pile settlement is carried out. Thus, the relationship between bridge pile group settlement and its variation with time is obtained. Finally, the proposed method is applied in pile settlement analysis of Taizhou Yangtze River Bridge, and it can provide guiding significance for the related engineering design.