The Liquid Limit as a Factor in Assessing the Improvement of Stabilized Cement-Based Highwater Content Clayey Sediments

Abstract

The purpose of this study was to assess the performance of high water content clayey sediments at different liquid limits as the clays are treated with cement-based solidifying materials. Three clay samples are obtained from different locations in the Kumamoto Reservoir. Two types of cement-based solidifying agents, namely, ordinary Portland cement and a cement–fly ash binder, were used. Using the initial water content of clay and the mixing amount of the solidifying agent as experimental variables, a cone penetration test was performed on the solidifying agent-stabilized clays to obtain the cone index (qc). The results showed that when the water content to cementitious content ratio (w/AW) was used as a parameter for evaluating the improvement of solidifying agent-stabilized clay, different forms of improvements were observed when different water and solidifying agent contents were used. This implied that the parameter w/AW was not suitable for evaluating the improvement of such clay. A new parameter, K, representing the content of solidifying agent, was introduced to account for the water content. For all sampled clays, the correlation coefficients for the K–ln qc relationship exceeded 0.9. Considering the effect of the liquid limit of the samples, the modified content of the solidifying agent (KL) was introduced to evaluate the cone index of the stabilized soils. It was discovered that the proposed equation unified the assessment of the improvement of the three samples of Kumamoto clayey sediments owing to the new parameter, KL.

Unconfined Compressive Strength of Cement-Stabilized Qiantang River Silty Clay

“…Finally, they proposed a unified method to characterize the UCS of all types of cemented sandy clays using a free-water-to-cement ratio, ( w / w L )/ c . Similarly, Zhang et al [ 9 ] also proposed a unified prediction method of UCS of three types of sandy clays incorporating water content, cement content, and liquid limit. The unified UCS- w / c relationship suggested by the present study is only applicable to clay without a substantial amount of sand.…”

“…However, USC can be affected by a variety of factors, including the type of soil, cement content, water content, water-to-cement ratio, curing time, types of admixtures, etc. [ 4 , 5 , 6 , 7 , 8 , 9 ]. There is no universal method to predict the UCS of cement-stabilized soils.…”

Feasibility Study of Low-Environmental-Load Methods for Treating High-Water-Content Waste Dredged Clay (WDC)—A Case Study of WDC Treatment at Kumamoto Prefecture Ohkirihata Reservoir in Japan

“…The cone index of the stabilized soil with both OPC and DF solidifying agents rapidly increased when their respective contents exceeded 200 kg/m 3 and 300 kg/m 3 . The difference in improvement between the ordinary Portland cement (OPC) and cement-fly ash binder (DF) is primarily due to the sufficient hydration products that favor the embedding of fly ash particles into the gel material voids, thus enhancing the strength of the stabilized clay [45]. Therefore, the test results indicate that DF with only 30% cement content requires a higher mixing ratio to promote water and product generation.…”