Soil–alkali interaction leads to abnormal soil behavior due to significant changes in mineralogy and morphology. The effect of alkali on the swelling behavior of natural clays has been explored in recent years, but the swelling behavior of alkali-transformed clay minerals is still unclear. The objective of the current study was to investigate the effect of alkali concentration on swelling characteristics of natural and alkali-transformed kaolinitic clays. The study was complemented further with micro-level investigations. Red earth and kaolin, which are regarded as non-swelling kaolinitic clays, were utilized. The results showed that alkalis induced greater swelling in natural clays than in alkali-transformed clays. The results revealed further that alkali-transformed clays exhibited decreases in swelling when exposed to increased alkali concentrations. Moreover, the degree of transformation played an important role in the swelling behavior of alkali-transformed kaolinitic clays when inundated with water and with various alkali concentrations. These variations may be attributed to the different extents of mineralogical and microstructural changes caused by alkali treatment.

中文翻译：

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碱浓度对转化高岭土溶胀特性的影响

由于矿物学和形态学的显着变化，土壤-碱相互作用导致土壤行为异常。近年来，人们对碱对天然粘土溶胀行为的影响进行了探索，但碱转化粘土矿物的溶胀行为尚不清楚。本研究的目的是研究碱浓度对天然高岭土和碱转化高岭土溶胀特性的影响。该研究进一步补充了微观层面的调查。红土和高岭土被认为是不溶胀的高岭土粘土。结果表明，碱在天然粘土中比在碱转化粘土中引起更大的膨胀。结果进一步表明，当暴露于增加的碱浓度时，碱转化粘土表现出溶胀降低。此外，当被水和各种碱浓度淹没时，转化程度对碱转化高岭土的溶胀行为起着重要作用。这些变化可能归因于碱处理引起的不同程度的矿物学和微观结构变化。