TY - GEN A1 - Geißler, Peter T1 - Modelling of compaction grouting using the implicit MPM N2 - Compaction grouting involves the injection under high pressure of a highly viscous grout into the soil to displace and compact the surrounding soil without fracturing it. This ground improvement technique has been used widely for settlement control, increasing liquefaction resistance or bearing capacity of soil under new or existing structures. The work presented here aims to show some numerical and experimental investigations being carried out to understand the compaction mechanism and the soil-grout interaction, which is crucial for a successful usage of this technique. To investigate compaction grouting in the laboratory under various stress conditions, a large-scale testing chamber has been developed. The grout was injected directly at the transparent vertical window of the chamber in order to investigate the possibility to monitor the injection process with a camera to measure the in-plane soil displacements and strains by means of the PIV technique. The other aim of this study is to develop a numerical model, which should be able to deal with large displacements and deformations and to simulate the change in shape of the distinct soil-grout interface solely as a result of the interaction between the injected grout and the surrounding soil. Based on these considerations, as a numerical technique, we employ the implicit Material Point Method based on a mixed formulation, which is implemented in the open source Kratos Multiphysics framework. In contrast to standard FE formulations, the usage of the MPM avoids both the numerical instability caused by extensive mesh distortion and the high computational costs of remeshing. The main results focus on the different evolution of the grout bulb inside the soil under various stress states. T2 - 28th ALERT Workshop CY - Aussois, France DA - 02.10.2017 KW - Compaction grouting KW - Soil-grout interface KW - Material point method (MPM) KW - Mixed formulation KW - Particle image velocimetry (PIV) PY - 2017 UR - https://opus4.kobv.de/opus4-bam/frontdoor/index/index/docId/42432 AN - OPUS4-42432 AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany