软土地基电动化学加固法的试验研究

Experimental study on electrochemical reinforcement of soft soil ground

针对软土地基电动化学加固方法的相关机理和对土体性质变化的影响规律,提出了金属电极端部效应对电极的工作性能产生不利影响,讨论了土体强度的增长机制,并通过大尺寸模型试验和现场试验,验证所提出概念的正确性,结合现场试验获取了土体含水率、黏聚力、内摩擦角实测数据,探究了电动化学加固对土体物理力学和化学性能的影响。利用电动化学灌浆加固技术对珠海地区的软基进行了加固,结果表明,应用电动化学灌浆加固技术可以有效降低软土的含水率和改变软土的塑性,加固后软土的平均抗剪强度提高了3倍以上,软土的流动性显著降低。该方法能耗低、施工工期短、不需要大型施工设备、现场易于操作;灌入的化学浆液以及发生化学反应后生成的盐和沉淀物对周围环境无污染。

In view of the relevant mechanism of electro-chemical reinforcement method for soft soil ground and the law of its influence on soil properties,the adverse effect of metal electrode extremity on electrode performance was proposed,and the mechanism of soil strength increase was discussed.The correctness of the proposed concept was verified by large-scale model tests and field experiments.The effects of electro-chemical reinforcement on the physical,mechanical and chemical properties of soil mass were investigated based on the field data of soil moisture content,cohesion and internal friction angle obtained from field experiments.The electro-chemical grouting technique is used to strengthen the soft ground in Zhuhai area.The results show that the application of electro-chemical grouting technique can effectively reduce the water content of the soft ground and change the plasticity of the soft soil,the average shear strength of the soft soil is increased by more than 3 times,and the fluidity of the soft soil is significantly reduced.This method has the advantages of low energy consumption,short construction period,no need of large construction equipment and easy operation on site.The chemical slurry injected and the salt and sediment generated after the chemical reaction are pollution-free to the surrounding environment.