外加电场改性处理高填方黄土地基的试验研究

摘要

External electric field treatment can improve and reinforce soil. Proper amounts of modified materials such as lime and sodium sulfate were added to the loess, which would be compacted to meet the predetermined dry density, then a certain in-tensity of electric field was added on. The unconfined compression tests, direct shear tests, high pressure compression tests and collapsibility tests were carried out for the soil after curing. The test results show that the compressive strength and shear strength are bigger than that of the remolded loess while the compressibility is smaller, moreover the collapsibility has been removed under different degree of compaction. The microstructure is analyzed by using scanning electron microscope ( SEM) and the improving mechanism of the improved soils was studied. The results can provide references for further study and engineering application of external electric field treatment technology.%外加电场处理技术是一项新型土壤改性加固技术，具体操作步骤是先以一定量的石灰和硫酸钠为改性材料掺入黄土中拌和均匀，然后根据设计的干密度对混合土料进行压实，再对压实土样施加一定强度的外加电场处理。养护完成后对土样进行无侧限压缩试验、直剪试验、高压固结与湿陷试验。试验结果表明，与压实重塑黄土相比，混合土料经电场处理后其抗压强度与抗剪强度提高，压缩性降低，且在各压实度条件下均无湿陷性。利用扫描电镜( SEM)对其微观结构进行初步观察，分析了新型固化技术加固黄土的机理，为外加电场处理技术的进一步研究和应用提供依据。