title: Compaction of highly porous granular matter by impacts on a hard wall.
abstract: Using a granular-mechanics code, we study the impact of a highly porous granular body on a hard wall. The projectile consists of monodisperse adhesive micrometer-sized silica grains. For the impact velocities studied, v<0.5m/s, the sample does not fragment, but is compacted. We find that the compaction is proportional to the impact speed. The proportionality constant increases with decreasing porosity. However, the compaction is inhomogeneous and decreases with distance from the target. A compaction wave runs through the aggregate; it slows down while the compaction becomes less efficient.
authors.affiliation: Physics Department and Research Center OPTIMAS, University Kaiserslautern, Erwin-Schrödinger-Straße, D-67663 Kaiserslautern, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Ringl
authors.affiliation: Physics Department and Research Center OPTIMAS, University Kaiserslautern, Erwin-Schrödinger-Straße, D-67663 Kaiserslautern, Germany.
authors.forename: Nina
authors.initials: N
authors.lastname: Gunkelmann
authors.affiliation: CONICET and Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo, Mendoza 5500, Argentina.
authors.forename: Eduardo M
authors.initials: EM
authors.lastname: Bringa
authors.affiliation: Physics Department and Research Center OPTIMAS, University Kaiserslautern, Erwin-Schrödinger-Straße, D-67663 Kaiserslautern, Germany.
authors.forename: Herbert M
authors.initials: HM
authors.lastname: Urbassek