IUTAM ISIMM Symposium on Mathematical Modeling and Physical Instances of Granular Flows : Reggio Calabria Italy 14 18 September 2009 Visco plasticity and micromechanics of rate dependent flow Elasto plasticity and micromechanics of rate indepedent flow: Non polar continuum modeling experiment numerical simulation statistical mechanics and statistical physics ; Polar continuum modeling : experiment and numerical simulation Segregation Waves