  This paper presents a hybrid continuum discrete macro modelling strategy with
a multiscale calibration procedure for realistic simulations of brick masonry
bridges. The response of these structures is affected by the intrinsic
nonlinearity of the masonry material, which in turn depends upon the mechanical
properties of units and mortar joints and the bond characteristics. Finite
element approaches based upon homogenised representations are widely employed
to assess the nonlinear behaviour up to collapse, as they are generally
associated with a limited computational demand. However, such models require an
accurate calibration of model material parameters to properly allow for masonry
bond. According to the proposed approach, the macroscale material parameters
are determined by an advanced multi objective strategy with genetic algorithms
from the results of mesoscale virtual tests through the minimisation of
appropriate functionals of the scale transition error. The developed continuum
discrete finite element macroscale description and the calibration procedure
are applied to simulate the nonlinear behaviour up to collapse of multi ring
arch bridge specimens focusing on the 2D planar response. The results obtained
are compared to those achieved using detailed mesoscale models confirming the
effectiveness and accuracy of the proposed approach for realistic nonlinear
simulations of masonry arch bridges.
