Dynamic analysis of quadrilateral concrete foundation integrated with NFRP layers based on numerical method

Mathematical modelling of quadrilateral concrete foundation is a novel topic in the literature. In this paper, dynamic response of quadrilateral concrete foundation resting on soil medium subjected to blast load is presented for the first time. The concrete foundation is covered by nano-fiber reinforced polymer (NFRP) layers at the top and bottom surfaces for improving the stiffness. The NFRP are containing carbon nano-fibers (CNF) and its equivalent material characteristics are calculated by Mori-Tanaka model incorporating the agglomeration effects. On the basis of Sinusoidal shear deformation theory (SSDT) and Hamilton's principle, the motion final equations are obtained assuming structural damping utilizing Kelvin-Voigt model. The dynamic deflection of the quadrilateral concrete foundation is discussed based on transformed weighing (TW) coefficients-differential quadrature method (DQM) in conjunction with Newmark method. The influences of different parameters of soil foundation, blast load, volume fraction and agglomeration of CNFs, structural damping, NFRP layer, geometrical parameters and side angles of the quadrilateral concrete foundation are shown on the dynamic displacement. The results are compared with other published works in the literature for presenting the accuracy of the applied model and method. The outcomes show that the dynamic defection will be reduced with enhancing the CNFs volume fraction. In addition, with with increasing the side angle of quadrilateral plate, the dynamic deflection is increased.