The fracture behavior parallel to the fibers of an E-glass/epoxy unidirectional laminate was studied by
means of three-point tests on notched beams. Selected tests were carried out within a scanning electron
microscope to ascertain the damage and fracture micromechanisms upon loading. The mechanical behavior
of the notched beam was simulated within the framework of the embedded cell model, in which the
actual composite microstructure was resolved in front of the notch tip. In addition, matrix and interface
properties were independently measured in situ using a nanoindentor. The numerical simulations very
accurately predicted the macroscopic response of the composite as well as the damage development
and crack growth in front of the notch tip, demonstrating the ability of the embedded cell approach to
simulate the fracture behavior of heterogeneous materials. Finally, this methodology was exploited to
ascertain the influence of matrix and interface properties on the intraply toughness
