OICC Press Journal of Solid Mechanics 2008-7683 4 2 2012 06 30 Nonlinear Finite Element Eccentric Low-Velocity Impact Analysis of Rectangular Laminated Composite Plates Subjected to In-phase/Anti-phase Biaxial Preloads 177 194 EN M Shariyat Faculty of Mechanical Engineering, K.N. Toosi University of Technology M Moradi Faculty of Mechanical Engineering, K.N. Toosi University of Technology S Samaee Faculty of Mechanical Engineering, K.N. Toosi University of Technology Journal Article 2012 06 30 All impact analyses performed so far for the composite plates, have treated central impacts. Furthermore, investigations on influences of the in-plane biaxial compression, tension, or tension-compression preloads on various responses of the low-velocity impact, especially the indentation, have not been performed so far. In the present research, a finite element formulation is presented for response prediction of a low-velocity eccentric impact between a rigid spherical indenter and a laminated composite rectangular plate with asymmetric lamination scheme. Different contact laws are considered for the loading and unloading phases. A parametric study is performed to investigate influence of the specifications of the plates and the indenter, the eccentric value, and the in-plane preloads on the indentation and force time histories. Results show that the compressive and tensile in-plane preloads reduce and increase the contact force (and consequently, the indentation values), respectively. Therefore, the extensive tensile preloads may lead to higher damages.