Baldovino Jair Arrieta, Diaz Kevin Cardenas, Royero Jorge Martínez, Sierra Rohonal Serrano, Nuñez de la Rosa Yamid E
Civil Engineering Program, Universidad de Cartagena, Cartagena de Indias 130015, Colombia.
Faculty of Engineering and Basic Sciences, Fundación Universitaria Los Libertadores, Bogota 110231, Colombia.
Materials (Basel). 2025 Apr 9;18(8):1720. doi: 10.3390/ma18081720.
This study explores using natural rubber latex (NRL) as a sustainable polymeric additive to improve the mechanical performance of cement-stabilized soil-crushed limestone waste (CLW) mixtures for pavement base applications. The experimental program involved varying cement contents (3%, 6%, and 9% by weight of soil) and NRL replacement levels (10%, 15%, 20%, and 25% of an 18% optimum water content, as determined by the standard Proctor test) under two target dry unit weights (16.6 and 17.6 kN/m) and curing periods of 7 and 28 days. Unconfined compressive strength (UCS) tests and stiffness (Go) measurements were performed, while microstructural developments were examined using scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS). The results indicate that an optimal NRL replacement exists for each cement content, enhancing interparticle bonding through the formation of polymeric films that reduce porosity and improve the ductility of the matrix. However, excessive NRL was found to retard cement hydration and ultimately decrease strength. On average, a 28-day curing period produced a 38% increase in UCS over 7-day values, independent of the NRL dosage. Comparisons with literature standards, including the ASTM D4609 threshold of 345 kPa for field strength, confirm that the optimized mixtures meet and exceed the minimum performance requirements. These findings underscore the potential of NRL as a viable alternative to conventional synthetic latexes in sustainable pavement base materials.
本研究探索使用天然橡胶胶乳（NRL）作为一种可持续的聚合物添加剂，以改善用于路面基层的水泥稳定土 - 碎石灰石废料（CLW）混合物的力学性能。试验方案包括在两种目标干容重（16.6和17.6kN/m³）以及7天和28天的养护期下，改变水泥含量（按土重的3%、6%和9%）和NRL替代水平（占通过标准普氏试验确定的18%最佳含水量的10%、15%、20%和25%）。进行了无侧限抗压强度（UCS）试验和刚度（Go）测量，同时使用扫描电子显微镜（SEM）和能谱仪（EDS）研究微观结构的发展。结果表明，对于每种水泥含量都存在一个最佳的NRL替代量，通过形成聚合物膜增强颗粒间的粘结，从而降低孔隙率并提高基体的延展性。然而，发现过量的NRL会阻碍水泥水化并最终降低强度。平均而言，28天的养护期使UCS比7天的值提高了38%，与NRL用量无关。与文献标准（包括现场强度的ASTM D4609阈值345kPa）的比较证实，优化后的混合物达到并超过了最低性能要求。这些发现强调了NRL作为可持续路面基层材料中传统合成胶乳的可行替代品的潜力。
