真空电渗联合振动碾压加固超软黏土试验研究

对于含水率高、强度低、压缩性大以及渗透性低的超软黏土地基,常规的真空电渗联合动力挤密加固技术(低能量强夯+电渗降水)容易产生"橡皮土"现象,以振动碾压代替强夯开展真空电渗联合振动碾压加固超软黏土试验,并同步开展单独真空电渗降水的对比试验。试验结果表明:振动碾压在挤密土体的同时增大渗流路径的压差,提高真空电渗排水速率;闭合电渗产生的裂缝,从而增强土体中的电流,并维持土体内的真空度;加快固结速度,减小单位排水量的电渗能耗。有必要结合实际工程开展现场试验进一步验证。

Experimental study of combined application of vacuum electroosmotic drainage and vibration rolling in ultra-soft clay improvement

For the ultra soft clay characterized by high moisture content,low strength,compressibility and low permeability,the conventional method of soft foundation reinforcement,which combined vacuum electroosmotic and low energy dynamic compaction,is prone to form rubber soil.Therefore,the dynamic compaction replaced by vibration rolling is suggested,and the laboratory tests of vacuum electroosmotic drainage with and without vibration rolling are carried out.The result shows that the vibration rolling can increase the difference of the water head in the soil and improve velocity of the vacuum electroosmotic drainage;the soil fissure caused by electroosmosis can be closed by the vibration rolling,which increases the current and keeps the vacuum degree of the soil;the vibration rolling can hasten the rate of consolidation and reduce the energy consumption also.This new method is necessary to be verified in the engineering practice.