Bentonite is commonly utilized as a waterproofing and buffering material due to its high expansibility and very low permeability. The cation exchange capacity is a crucial parameter that influences the microstructure of montmorillonite

thereby modifying its expansibility

hydraulic properties

and diffusion characteristics. Various montmorillonite samples with reduced cation exchange capacity were produced by heating lithium-modified bentonite at varying temperatures. By employing nuclear magnetic resonance and X-ray diffraction techniques

we acquired information on the distribution of pore water and interlayer spacing in montmorillonite with reduced cation exchange capacity under varying water content. Furthermore

we investigated the effect of cation exchange capacity on hydration in montmorillonite interlayers. The research demonstrates that a decrease in cation exchange capacity results in a reduction in the number of expandable layers

consequently lowering the liquid limit of bentonite. An preliminary approach for determining the proportion of expandable layers is suggested using the T distribution curve derived from nuclear magnetic resonance. The results from this method closely align with the proportion of reduced exchangeable cations.