Abstract:

A field experiment of high energy dynamic compaction (HEDC) with 15 000 kN•m was carried out on a rubble fills site underlain by soft interlayer along coastal area for the first time in China. The ground settlements of drop points and their surrounding areas during a single drop DC are monitored, the dynamic penetration test (DPT) is carried out before and after HEDC. The test results are comprehensively analyzed, and the comparative studies are systematically done. Furthermore, the reinforcement mechanism of HEDC is discussed on a rubble fills site underlain by soft interlayer underlain, and some conclusions such as effective depth of improvement (EDI) on rubble fills site with 15 000 kN•m HEDC are drawn. It is recommended that the EDI should be 11.5 m, the intervals of 12.5 m between main drop points, and the drop numbers of 18-22 are suitable for a rubble fills foundation underlain by soft interlayer.

Key words: high energy dynamic compaction(HEDC), 15 000 kN•m, soft interlayer underlain, dynamic penetration test(DPT), effective depth of improvement (EDI)