Abstract: The detailed subsurface geotechnical investigation results indicate the poor and heterogeneous conditions underneath the proposed coalburning boiler of No. 2 CoalSteam Converting Station of Fengcheng Oil Field. The subsurface soils could not meet the design requirement as well as a wetting collapse exists in the soils. The feasibility of the soil improvement analysis indicates that the dynamic compact is the most cost effective method for the strengthening the soil strength and eliminating the wetting induced collapse in loess soils. The third party insitu testing results before and after the improvement demonstrated the success of applying this method.

Key words: Wetting Induced Collapse, Dynamic Compaction, Cost Comparisons, Improvement Verifications