Rigid-Body-Spring Network with Visco-Plastic Damage Model for Simulating Rate Dependent Fracture of RC Structures
The mechanical properties of concrete materials vary with the loading rate underdynamic conditions, which can inﬂuence the dynamic fracture behavior of structures. The ratedependency is reported as due to the microscopic mechanisms, such as a material inertia eﬀectand the Stefan eﬀect. In this study, the rigid-body-spring network (RBSN) is employed forthe fracture analysis, and the visco-plastic damage model is implemented to represent the rateeﬀect in this macroscopic simulation framework. The parameters in the Perzyna type visco-plastic formulation are adjusted through the direct tensile test with various loading rates asa preliminary calibration. As the loading rate increases, the strength increase is presented interms of the dynamic increase factor (DIF), and compared with the experimental and empiricalresults. Next, the ﬂexural beam test is conducted for plain and reinforced concrete beams underslow and impact rates of loading. At the failure stage, diﬀerent crack patterns are observeddepending on the loading rate. The impact loading induces the failure to be more localizedon the compressive zone of the beam, which is due to rather the rate dependent materialfeatures. In structural aspects, the reinforcement exerts stronger eﬀects on reducing crack widthand improving ductility at the slow loading rate. The ductility is also evaluated through thecomparison of load-deformation curves until the ﬁnal rupture of the beams. This study canprovide understandings of the structural rate dependent behavior and the reinforcing eﬀectunder dynamic loadings.
Ezio Cadoni and Marco di Prisco
K. Kim et al., "Rigid-Body-Spring Network with Visco-Plastic Damage Model for Simulating Rate Dependent Fracture of RC Structures", Applied Mechanics and Materials, Vol. 82, pp. 259-265, 2011