为研究高庙子钠基（GMZ01）膨润土在碱性孔隙水长时间侵蚀下膨胀变形的变化规律，将GMZ01膨润土与1 mol/L 的NaOH溶液混合密封放置一定预定时间进行化学反应后，将其制成压实试样于蒸馏水中进行膨胀变形试验，发现试样的膨胀性能随碱性孔隙水作用时间的增加而减小.通过对不同反应时间的膨润土试样进行矿物成分分析，发现膨润土中蒙脱石含量随反应时间的增加而逐渐减小，而长石等矿物含量逐渐增大，表明在NaOH溶液长期作用下蒙脱石被逐渐溶解生成非膨胀性的长石等矿物，进而导致膨润土膨胀性能逐渐衰减.基于膨胀分形模型对碱性溶液混合试样的膨胀变形试验数据进行整理分析，发现不同反应时间试样的蒙脱石孔隙比与考虑了孔隙水渗透吸力的有效应力之间均符合统一的em-pe分形关系，表明被NaOH溶液溶蚀后试样的膨胀变形衰减主要是受蒙脱石含量减小的影响，而蒙脱石的其他性质变化较小.
The GMZ01 bentonite was mixed with 1 mol/L NaOH solution and sealed tightly. After different preset time of placement, the swelling deformation tests of specimens were produced in distilled water to research the variation of swelling characteristics influenced by the alkaline pore water during long time, and the swelling property was found to decrease with the reaction time. Mineral composition analysis of the specimens reveals a decrease in the montmorillonite content with reaction duration while an increase in the feldspar content, and suggests that during the longtime exposure to NaOH solution, the montmorillonite dissolute gradually to precipitate the non-swelling minerals, leading to the swelling attenuation. The swelling fractal model was employed to analyze the swelling test results, the montmorillonite void ratio of specimens during different reaction time can be expressed by a unique em-pe fractal relationship using an effective stress incorporating with osmotic suction of pore water. It suggests the swelling deformation of specimens corroded by NaOH solution are mainly dependent on the montmorillonite content with few variation in the other properties of montmorillonite.
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