The American Concrete Institute (ACI) has released a paper called Cement Type Effect on Improvement of Clayey Soil Properties.
The document, written by Murat Mollamahmutoglu and Eyubhan Avci, investigated and compared some geotechnical properties of low-plasticity clay blended with calcium aluminate cement (CAC) at different contents with those of sulfate-resistant cement (SRC)-blended low-plasticity clay.
ACI says: “As the liquid limits of CAC and SRC-blended low-plasticity clay decreased, their plastic limits increased. Additionally, the liquid limit and the plastic limit of CAC-blended low-plasticity clay were found to be lower than those of SRC-blended low-plasticity clay.”
The findings revealed that CAC and SRC agents increased the optimum moisture content and maximum dry density of low-plasticity clay. Also, the optimum moisture content and maximum dry density values of CAC-blended low-plasticity clay were higher than those of SRC-blended low-plasticity clay.
“The shear strength of low-plasticity clay was also increased with the CAC and SRC additives. The internal friction angles of CAC-blended low-plasticity clay were higher than those of SRC-improved low-plasticity clay under both the wet-cured and air-dried conditions,” ACI adds.
The cohesion intercepts of CAC-improved low-plasticity clay under both the wet-cured and air-dried conditions were lower than those of SRC-improved low-plasticity clay. Additionally, the compressibility and swell characteristics of low-plasticity clay were considerably reduced with both CAC and SRC admixtures.
“However, the swell and compressibility of CAC-blended low-plasticity clay were lower than those of SRC-blended low-plasticity clay. Generally, the CAC agent was more effective than the SRC agent in the improvement of aforementioned low-plasticity clay properties,” ACI concludes.
