Experimental investigation on the lateral deformation of soft ground under combination of vacuum pressure and surcharge load

摘要

Laboratory large scale model (length: 1.50 m, width: ～0.62m, height: 0.85 m) tests were conductedrnto investigate the characteristics of lateral displacement of soft ground under the combination ofrnvacuum pressure and surcharge load. The surcharge loading system consists of 3 Bellofram cylinders and 3rnsteel loading plates. To simulate the embankment load, the load applied to two side loading plates was half ofrnthe value of the center one. The technique of applying vacuum pressure is called vacuum-drain method whichrnuses a surface soil layer as sealing layer. Denoting the ratio of surcharge load to measured final vacuum pressurernas RL_m, 4 cases with RL_m = 0.8 to 2.0 were tested. The test results show that the outward lateral displacementrnof the model ground increases with the increase of RLm. The maximum outward lateral displacement forrnRL_m = 2.0 is about 3.5 times of RL_m = 0.8. The test results suggested that it is possible to minimize or controlrnthe lateral displacement by adjusting the ratio of load.