Experimental study on artificial marine clay: Preparation and structural characteristics

Laboratory testing is a fundamental approach in marine geotechnical engineering; however, obtaining undisturbed submarine deposits remains technically challenging and economically costly. Therefore, developing effective methods to simulate marine clay under controlled laboratory conditions is of both scientific and practical significance. This study proposes a rapid preparation methodology for artificially structured specimens exhibiting the high void ratio, sensitivity, and strain-softening characteristics representative of marine clays. Using kaolin as the base material, a layered compaction–vacuum–saturation technique was developed to efficiently prepare highly saturated specimens ( S r >95%). Portland cement and sodium silicate were introduced to stabilize large-void-ratio specimens and reproduce the high sensitivity characteristic of natural marine clays. Vane shear tests showed that the sensitivity of the artificially structured specimens ranged from 4.8 to 11.6 and was primarily governed by cement content. The strain-softening characteristics were further evaluated using the ξ 95 parameter derived from shear strength degradation curves. Through systematic investigation of admixture contents and void ratios, a preparation framework was established for producing artificial structured clay specimens with targeted undrained shear strength, sensitivity, and representative structural characteristics. These findings provide a reliable material preparation approach for physical model testing and laboratory investigations in marine geotechnical engineering.