Preparation of the non-cohesive soil sample and calibration of the pneumatical launcher in the dynamic soil test SHPB

Abstract

The paper analyzes the problem of initial compaction of a non-cohesive soil sample on the example of dry silty sand samples. Two different compaction methodologies were used: I) dynamic compaction - using split Hopkinson pressure bar and II) vibration compaction - using a vibrating shaker. A better result of the compaction process was obtained for dynamic compaction with an initial pressure value of 0.5 bar (small difference in the result - both methods obtained comparable results). The paper also includes a numerical analysis of the calibration of the pneumatic launcher in the Matlab environment on the basis of the system of difference equations. The calibration process was carried out in the initial pressure range from 0.5 to 3.0 bar for three different variants of the bar-projectile length: 100 mm, 200 mm and 250 mm and compared with the experimental analysis - the results were consistent.