Dynamic Behavior of Beam–Pile Structure Under Vertical Transient Excitation

Abstract

The dynamic response of beam–pile–soil system under vertical transient excitation is investigated. Both piles and beam are assumed to be one-dimensional rods and subjected to vertical exciting forces. The uniformly distributed Voigt models are introduced to simulate the pile tip resistances, and the dynamic interactions between piles and beam are simplified as a set of concentrated point loads. Then, the plane strain model, the theory of longitudinal vibration of one-dimensional rod, and the Timoshenko beam theory are used to establish the mathematical models for the motion of soil, piles, and beam, respectively. On this basis, the matrix equation for solving the governing equations is constructed in the Laplace domain and the time-domain response is then obtained by the discrete inverse Fourier transform. Comparisons with numerical simulations and model tests are conducted to evaluate the rationality of the present solution. The results show that the dynamic responses calculated by the proposed solution are generally consistent with simulated curves and experimental data.