The Experimental Research of Slurry Improvement with Different Kinds of Vertical Drains under New Vacuum Conditions

Abstract:

The results of experimental research are presented and discussed with focus on the ground improvement effect of slurry with different kinds of vertical drains under new vacuum conditions. In these conditions, horizontal sand cushion, which is requested in regular vacuum preloading method, is cancelled. Vertical drains are connected with sealed pipes, so the vacuum head can be transmitted into vertical drains without decreasing. For the experimental research, slurry taken from reclaimed soil zone is placed into six model casing boxes. Different kinds of vertical drains (prefabricated vertical drains (PVDs) and sand drains) are installed into the soil with different spacing (0.4 m and 0.8 m). A vacuum pressure of 80 kPa was applied continuously for 90 days. The effect of filter type of PVD, type of vertical drain and drain spacing under new vacuum preloading condition to slurry soil improvement is examined. Test results show that this new vacuum preloading condition can transmit vacuum head into vertical drains efficiently and the effect of drain filter to slurry improvement is affected by the drain spacing.

• Periodical: Applied Mechanics and Materials (Volumes 405-408)
• Pages: 396-401
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.405-408.396
• Online since: September 2013
• Authors: Jian Chen, Qiao Liang Tang, Shi Jing Liu
• Keywords: Energy Efficiency, New Vacuum Conditions, Soft Ground Improvement, Vertical Drain

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