电渗注浆加固土遗址片状剥离实验研究

Experimental study on electro-osmosis grouting reinforcement of scaling off earthen sites

片状剥离是具有二元结构特征的干旱区土遗址常见病害,常规的渗透方法对片状剥离加固效果不甚理想。研究以电渗法为借鉴,通过研制电渗装置并进行常压滴渗和电渗注浆的片状剥离对比渗透加固试验,证明电渗注浆能均匀加固半径与扩展加固深度。在此基础上以硅酸钠溶液进行不同电极布置形式下的电渗注浆渗透试验,通过分析试验过程中电流、注浆量、能耗系数变化遴选出正六边形为最优布置形式。然后以最优布置开展3种加固溶液的电渗注浆现场加固试验和加固土体的相关性质测试,研究结果表明:糯米浆和硅酸钠溶液不适用于电渗注浆加固;SH溶液电渗注浆加固后片状剥离层间黏结紧密,加固区土体贯入阻力、硬度、波速、抗风蚀性能和抗崩解性能均较未加固土体有显著提升。

Scaling off is a common disease of earthen sites with dual structure characteristics in arid areas,and conventional infiltration methods are not ideal for scaling off reinforcement. Using electroosmosis as a reference,an electroosmosis equipment was developed and penetration and reinforcement tests of atmospheric dripping and electroosmosis grouting were carried out. It is found that electroosmosis grouting can uniformly penetrate the radius and expand the penetration depth. On this basis,electroosmosis grouting penetration tests with sodium silicate solution were carried out under different electrode layouts. Regular hexagon was selected as the optimal layout by analyzing the changes in current,grouting volume and energy consumption coefficient during the test. Then,the field reinforcement tests of electroosmosis grouting of three kinds of reinforcement solutions and the related property test of the reinforced soil were carried out with the optimal layout. It is shown that glutinous rice slurry and sodium silicate solution are not suitable for electroosmosis grouting reinforcement,while that,after electroosmosis grouting by SH solution,the bonding between the scaling off layers is tight,and the penetration resistance,hardness,wave speed,wind erosion resistance and disintegration resistance of the soil in the reinforced area are significantly improved compared with the unreinforced soil.