لحساب قوة التلامس باستخدام كتل صلبة وزنبرك

Spring-mass model is developed to calculate the contact force history during low velocity impacts on composite plates. It includes the influence of damping effects on the contact area and can take into account fiber fracture or other damage events with appropriate modifications of the relevant parameters.
The model describes the impactor and the target laminate by two rigid masses, while the contact interaction is represented by a Hertzian spring and a non linear viscous damper and the deformation behavior of the laminate by a combination of bending and membrane springs.
To incorporate major damage events in the model, the bending and membrane stiffness of the composite plate may be reduced, after reaching a critical load, to account for the degradation of the material associated to the progression of broken fibers. In this case, the reduced stiffness values introduced in the model were obtained by post-failure FEM calculations as a function of contact force and extension of fiber fracture