COMPUTATIONAL MODELLING OF RC SLABS CRACKING WITH AN EMBEDDED DISCONTINUITY FORMULATION

Abstract

THIS PAPER INVESTIGATES THE CRACKING PROCESS OF REINFORCED CONCRETE SLABS SUBJECT TO VERTICAL LOAD, INVOLVING THEIR CRACK PATTERN AND THE LOAD-DISPLACEMENT CAPACITY CURVE. CONCRETE WAS DISCRETIZED WITH HEXAHEDRAL FINITE ELEMENTS WITH EMBEDDED DISCONTINUITIES; WHERE-AS STEEL REINFORCEMENT WAS REPRESENTED BY 3D BAR ELEMENTS, PLACED ALONG THE EDGES OF THE SOLID ELEMENTS, BOTH KINDS OF ELE-MENTS HAVE THREE DEGREES OF FREEDOM PER NODE. THE CONSTITUTIVE BEHAVIOUR OF CONCRETE CONSIDERS THE SOFTENING DEFORMATION AFTER REACHING A FAILURE SURFACE, WHEREAS THE HARDENING OF THE REINFORC-ING STEEL IS REPRESENTED BY A 1D RATE INDEPENDENT PLASTICITY MODEL WITH ISOTROPIC HARDENING. THE COUPLING OF SOLID AND BAR FINITE ELE-MENTS WAS VALIDATED WITH A REINFORCED CONCRETE SLAB REPORTED IN THE LITERATURE; OTHER TWO SLABS WERE ALSO INVESTIGATED SHOWING THEIR CRACKING PATTERS AT THE TOP AND AT THE BOTTOM SURFACES.