Origin of compaction bands: Anti-cracking or constitutive instability?

►Different types of compaction bands have been reproduced in the numerical models. ►These bands can form only when the hardening modulus H is between Hmax and Hmin. ►The band type depends notably on H and the dilatancy factor Beta. ►Dense zigzag bands form when H is close to Hmin and Beta is slightly negative. ►Long, linear bands form when H approaches Hmax and Beta has high negative value.