Laboratory experimental study on electroosmotic drainage technology of low-permeability dense clay
LI Jindian1，2，HAN Meng1，2，FENG Haiyang1，2，CHEN Yafei1，2
(1. China Coal Technology and Engineering Group Shenyang Research Institute，Fushun，Liaoning 113122，China；
2. State Key Laboratory of Coal Mine Safety Technology，Fushun，Liaoning 113122，China)
Abstract：Many achievements of electroosmotic drainage technology have been made in soft soil foundation reinforcement. Low-permeability dense clay was not well reinforced by conventional drainage consolidation method. In order to solve the problem，a low permeability dense clay sample of an open pit coal mine was selected. The electroosmotic drainage test was carried out on undisturbed soil and remolded clay samples in the laboratory. The results show that the electroosmotic drainage was divided into initial drainage stage，stable drainage stage，and later drainage stage. In practical engineering，the sharp decrease of current can be used as the end sign of electroosmotic drainage to avoid increasing energy consumption in the later drainage stage. During the reinforcement of low-permeability dense undisturbed clay by electroosmotic drainage method，the water content decreased by 13.4 % on average, the bearing capacity increased by 1.34 times on average，and the shear strength increased by 1.85 times on average. In addition，under the same conditions，the plate electrode layout has a better reinforcement effect on soil，but the electrode parallel dislocation layout is more suitable for practical engineering.
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2021, Vol. 40 
