Soil replacement 2. Preloading 3. Preloading with vertical drains 4. Water removal by trenching technique 5. Vibro-compaction 6. Electro-osmosis 7. Dynamic compaction 8. Vibro-replacement 9. Vibro-displacement 10. Geosynthetics 11. Thermal method of soil improvement 12. Grouting Read more about it here.