The efficiency of calcium lignosulfonate (CLS) as an expansive soil stabiliser was studied. CLS is a bio-based polymer, obtained as a sub-product of the paper industry. Its use as a soil stabilizer not only enhances the properties of the soil but also eliminates the economic and environmental costs of its disposal. In this project, CLS was added to a natural smectite clay (Clay) from Comodoro Rivadavia, Argentina. Smectite clays exhibit significant plastic volumetric deformations when subjected to moisture variations. Clay was stabilised using 3.0 and 5.0% mass of CLS. The efficiency of CLS as a stabilising agent was measured studying its influence on the physical properties of Clay (Atterberg limits, Cation Exchange Capacity, Specific Surface Area). Considerable reductions of the cation exchange capacity (CEC) and the specific surface were registered. Furthermore, a full hydro-mechanical characterisation of Clay with CLS was performed in saturated and unsaturated conditions. Results from free swell and swelling pressure tests show that CLS reduces by nearly a half and nearly a quarter the free swell and swelling pressure of Clay, respectively. Additionally, mercury intrusion porosimetry (MIP) and scanning electron microscopy (SEM) tests were carried out to evaluate the microstructure re-arrangement of Clay when CLS was added. Results showed that a relatively small amount of CLS might yield a reasonably satisfactory performance as a stabiliser, particularly in reducing the natural Clay’s swelling potential. Moreover, CLS induced an increase in the stiffness and strain at failure of Clay and a reduction in its porosity.

研究了木质素磺酸钙（CLS）作为膨胀土稳定剂的效率。CLS是一种生物基聚合物，是造纸工业的副产品。它作为土壤稳定剂的用途不仅可以增强土壤的特性，而且还消除了其处置的经济和环境成本。在此项目中，将CLS添加到了来自阿根廷Comodoro Rivadavia的天然蒙脱石粘土（粘土）中。蒙脱石粘土在经受水分变化时表现出明显的塑性体积变形。使用3.0和5.0％质量的CLS稳定粘土。通过研究CLS作为稳定剂的效率，研究其对粘土的物理性能（Atterberg限值，阳离子交换容量，比表面积）的影响。记录到阳离子交换容量（CEC）和比表面积显着降低。此外，在饱和和不饱和条件下用CLS对粘土进行了完整的水力力学表征。自由膨胀和膨胀压力测试的结果表明，CLS分别使粘土的自由膨胀和膨胀压力降低了近一半和近四分之一。此外，还进行了压汞法（MIP）和扫描电子显微镜（SEM）测试，以评估添加CLS后粘土的微观结构重排。结果表明，相对少量的CLS可能会产生相当令人满意的稳定剂性能，尤其是在降低天然粘土的溶胀潜力方面。此外，