Consolidation Behavior and Compression Prediction Model of Coastal Cement Soil Modified by Nanoclay

Abstract

Coastal cement soil modified by nanoclay (NCS) has particular research significance as a modification approach to improve the high compressibility of coastal cement soil (CCS). At curing ages of 7 days and 28 days, consolidation and SEM tests were performed on 6 groups of NCS samples with a nanoclay content between 0% and 10% and 6 groups of CCS samples with a cement content between 10 and 20%, and a compression prediction model was established based on the test results. Test results show that (1) there is a linear interval for the improvement effect of the increment of cement content on the compression of CCS samples. In this test, the cement content in this interval is between 12% and 18%. CCS with a cement content of 18% is preferred. (2) The improvement effect on the compression of the sample is better with a nanoclay content of 4% and 8%, but poor with a content of 2%. At a consolidation pressure between 100 kPa and 800 kPa, NCS with a nanoclay content of 4% is preferred. (3) Adhesion is better with a nanoclay content of 4%, and the filling effect is better with a content of 8%. (4) The cosine-power function-exponential model is established, and the measured data are fitted, and a prediction model for the compression amount of CCS and NCS is established.

Experimental Study on the Mechanical Properties of Diatomite-Modified Coastal Cement Soil

“…The increase in the strength of coastal cement soil mixed with diatomite is mainly due to the large amount of active SiO 2 in diatomite. This active SiO 2 can react with the cement hydration product Ca(OH) 2 to generate hydrated calcium silicate gel (C-S-H), and C-S-H has strong cementation, thus improving the compressive strength of coastal cement soil [ 32 ]. With the increase in diatomite content, the peak strength still increased.…”

Modification Effect of Nano-Clay on Mechanical Behavior of Composite Geomaterials: Cement, Nano-Silica and Coastal Soft Soil

“…At present, many scholars at home and abroad have carried out much research on the use of nano-materials to modify coastal soft soil and proved its effectiveness [4,[15][16][17][18]. Compared with traditional materials, nano-materials have the characteristics of great specific surface area and minimal size, which have the ability to speed up cement hydration during the hydration reaction to effectively enhance the mechanical strength and durability of cement soil [19,20], and reduce environmental pollution, providing great possibilities for the sustainable development of the construction industry.…”