Structures that disapprove linearity: membranes, masonry structures, beams in contact with rough surfaces

The seminar addresses some major research topics of the nonlinear mechanics group. Masonry structures and thin membranes could not be more different. However they share a common feature. Both of them show a strongly nonlinear response, so that the corresponding equilibrium problem cannot be solved by means of the standard elastic theory. Nonetheless, it seems that a solution (although approximated) to these problems may be found by using suitable nonlinear elastic models. Some solution examples of masonry elements obtained by way of a one-dimensional model is presented. Membranes are studied by using the asymptotic model known as “wrinkle theory”. By this way, it is possible to find equilibrium solutions characterised by tensile stresses only (tension field). Friction is one among the major sources of nonlinearity in many different applications (even in masonry and membranes problems). The nonlinear dynamic response due to friction that may be observed in beams in contact with rough surfaces is the last topic. Some first considerations drawn from simple models are discussed.