针对电渗法与外荷载联合作用进行了室内试验,设计了9组对比试验,包括在相同外荷载作用下改变电渗电压、在相同电渗电压作用下改变外荷载作用以及单纯外荷载作用下的普通固结试验.对各组试验中的电路电流、土体出流、土体含水率分布、土体沉降、土体电导率、pH值等指标进行了量测,分析了外荷载、电渗电压对电渗过程的影响,并在外荷载与电渗电压之间建立了一定的联系.试验结果表明,增加外荷载对土样排水的促进作用优于提高电压梯度;外荷载作用能够促进阴极排水口处的出流量;在40 kPa外荷载作用下的普通固结与在0.5 V/cm电压梯度作用下的电渗固结作用及效果相当,在1 V/cm电压梯度作用下的电渗固结与在50 ∼60 kPa外荷载作用下的普通固结作用效果相当.研究及结果表明,外荷载与电渗法联合作用和单纯电渗法及单纯预压法相比,能够显著提高地基处理效果.
A series of tests were conducted to investigate the consolidation mechanism and effect of the combined application of electro-osmosis drainage and preloading. Test results for consolidation with variable voltage gradient, consolidation with variable loads and consolidation with constant preloading loads were presented and discussed. Current, soil flow, soil moisture content, displacement, soil conductivity, soil pH and other indicators were monitored during the tests. The effect of preloading loads and voltage gradient on electro-osmosis drainage was explored and the corresponding relationship between the preloading loads and the voltage gradient was established. The test results indicate that, compared to improved electro-osmosis voltage, increasing preloading loads can increase soil flow significantly. Preloading loads can increase soil flow at the cathode outfall. The effect of soil treatment with 40 kPa preloading loads is roughly equal to that of electro-osmotic consolidation with 0.5 V/cm voltage gradient. The effect of electro-osmotic consolidation with 1 V/cm voltage gradient is roughly equal to that of preloading with 50∼60 kPa loads.Compared to the effect of electro-osmosis drainage or preloading, the combined application of preloading and electro-osmosis drainage can significantly improve the effect of soil treatment.
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