Abstract: This paper studies the reinforcement of soft clay by dynamic consolidation with drainage.It develops a large-scale indoor simulation equipment and conducts some tests.It is focused on the monitoring and analyzing for settlement of tamping points as well as instantaneous and long-term variations of pore water pressure.The findings are that the wave generated by tamping spreads inward the soil and it can form stretcher fissures.The fissures become the first drainage channel.The variation of pore water pressure has fluctuations.At the tamping time it appears negative growth. Then it accumulates upward.The increasing range of pore water pressure is relevant with depth.The sand bedding can be used for drainage as well as static load for consolidation.