Abstract

The organic matter within clay soil is one of the important factors affecting its engineering characteristics. In this study, the influence of organic matter on the strength evolution of cement-stabilized marine soft clay is evaluated by scanning electron microscopy (SEM) and unconfined compressive strength (UCS) testing. The experimental results show that the after-curing clay water content of the specimens increased with the organic matter content. However, the after-curing unit weight decreased with the organic matter content. The strength decreased with the increase in the amount of organic matter. The strength loss (SL) increased with the organic matter content. A new mathematical model was determined and then used to quantitatively analyze the strength of the investigated samples. A relationship between the strength and organic matter content was established. The evaluation of the accuracy of this new strength model was carried out by comparing the predicted values and measured values, and the results indicated that the deviation was mostly within 10%. Finally, the microscopic changes of the sample surface and influencing mechanism of the organic matter were revealed through SEM. A high soil strength is mainly due to a relatively low porosity, a dense microstructure and the formation of hydration products.

摘要

粘土中的有机质是影响其工程特性的重要因素之一。在本研究中，通过扫描电子显微镜 (SEM) 和无侧限抗压强度 (UCS) 测试评估有机质对水泥稳定海洋软粘土强度演变的影响。实验结果表明，随着有机质含量的增加，试样的固化后粘土含水量增加。然而，后固化单位重量随着有机物含量的增加而降低。强度随着有机质含量的增加而降低。强度损失（SL）随着有机质含量的增加而增加。确定了一个新的数学模型，然后用于定量分析所研究样品的强度。建立了强度和有机物含量之间的关系。通过比较预测值和实测值对这种新强度模型的准确性进行评价，结果表明偏差大多在10%以内。最后，通过扫描电镜揭示了样品表面的微观变化和有机物的影响机制。较高的土壤强度主要是由于相对较低的孔隙率、致密的微观结构和水化产物的形成。通过扫描电镜揭示了样品表面的微观变化和有机物的影响机制。较高的土壤强度主要是由于相对较低的孔隙率、致密的微观结构和水化产物的形成。通过扫描电镜揭示了样品表面的微观变化和有机物的影响机制。较高的土壤强度主要是由于相对较低的孔隙率、致密的微观结构和水化产物的形成。