真空预压联合间歇电渗加固疏浚淤泥试验研究

Experimental study on dredged slurry improvement by vacuum preloading combined with intermittent electroosmotic

沿海地区疏浚工程产生大量疏浚淤泥。为了研究疏浚淤泥的处理方法,通过室内模型试验,对温州地区的疏浚淤泥进行分级真空预压联合间歇电渗的加固处理,并对间歇通电的时间及间歇逐级加压电渗进行研究。试验过程中监测真空压力、电流、排水量和土表的沉降;试验之后,对土体含水率、十字板剪切强度以及电极腐蚀质量进行测量。试验结果表明:虽然间歇通电时间越长,土体固结效果越好,但间歇通电时长超过24 h后,土体加固效果开始减弱;然而,电极腐蚀质量和间歇电渗的平均能耗系数却依然与间歇通电时长呈正相关。此外,分级真空预压联合间歇逐级加压电渗法相比于分级真空预压联合间歇电渗法获得了更佳的土体加固效果,并且其电极腐蚀质量和间歇电渗的平均能耗系数也显著降低。

A large number of dredged slurry are produced in coastal areas.In order to study the treatment methods of dredged slurry,an indoor model test had been conducted to reinforce dredged slurry in Wenzhou area by stepped vacuum preloading combined with intermittent electroosmosis.And the time of intermittent energization and intermittent stepped voltage electroosmosis has been studied.The vacuum pressure,electric current,water discharge and surface settlement were monitored during the test.After the test,the water content of the soil,vane shear strength of soil and the corrosion quality of the electrode were measured.The test results show that the longer the intermittent energization time,the better the soil consolidation effect.However,when the intermittent energization time exceeds 24 h,the soil reinforcement effect begins to weaken;The corrosion quality of electrodes and the average energy consumption coefficient of intermittent electroosmosis are still positively correlated with the time of intermittent energization.In addition,the stepped vacuum preloading combined with intermittent stepped voltage electroosmosis method has a better soil reinforcement effect than the stepped vacuum preloading combined with intermittent electroosmosis method.And the corrosion quality of electrodes and the average energy consumption coefficient of intermittent electroosmosis of the stepped vacuum preloading combined with intermittent stepped voltage electroosmosis method are also significantly reduced.