Sharif Digital Repository

In concrete which is a quasi-brittle material failure initially occurs between aggregate and mortars. Fibers of all orientations, randomly embedded in FRC, serve to restrict and delay the coalescence of micro-cracks, micro-voids and micro-slips into wide continuous cracks. While the fibers increase the uniaxial tensile and compressive strength only moderately, they are very effective for enhancing the ductility and energy absorption capability. This elevates structure resistance to impact, ground-shock and blast. One of the most successful efforts toward reaching a macroscopic model which can take micromechanical properties into account is the Microplane model. In this microscopic... 

Concrete as a heterogeneous, quasibrittle and practical material has always been a challenging material for modeling. Although numerous models have been proposed since now, many of them have some deficits. Microplane is a multiscale model which introduces some micro-planes as interaction planes between concete and aggregates. To generate concrete behavior, stress-strain relations are established on these micro-planes. In the present study, two prominent microplane models, M2 and M4, has been used in 2D and 3D Finite element framework. M2 model has been applied and developed to produce FRC behavior for uniaxial tension and compression under static and cyclic loading. To better optimize M2...