Soltani Amin, Raeesi Ramin, Taheri Abbas, Deng An, Mirzababaei Mehdi
School of Engineering, IT and Physical Sciences, Federation University, Churchill, VIC 3842, Australia.
Department of Infrastructure Engineering, The University of Melbourne, Parkville, VIC 3010, Australia.
Polymers (Basel). 2021 Feb 28;13(5):764. doi: 10.3390/polym13050764.
This study examines the potential use of sodium alginate (SA) biopolymer as an environmentally sustainable agent for the stabilization of rubberized soil blends prepared using a high plasticity clay soil and tire-derived ground rubber (GR). The experimental program consisted of uniaxial compression and scanning electron microscopy (SEM) tests; the former was performed on three soil-GR blends (with GR-to-soil mass ratios of 0%, 5% and 10%) compacted (and cured for 1, 4, 7 and 14 d) employing distilled water and three SA solutions-prepared at SA-to-water (mass-to-volume) dosage ratios of 5, 10 and 15 g/L-as the compaction liquid. For any given GR content, the greater the SA dosage and/or the longer the curing duration, the higher the uniaxial compressive strength (UCS), with only minor added benefits beyond seven days of curing. This behaviour was attributed to the formation and propagation of so-called "cationic bridges" (developed as a result of a "Ca/Mg ⟷ Na cation exchange/substitution" process among the clay and SA components) between adjacent clay surfaces over time, inducing flocculation of the clay particles. This clay amending mechanism was further verified by means of representative SEM images. Finally, the addition of (and content increase in) GR-which translates to partially replacing the soil clay content with GR particles and hence reducing the number of available attraction sites for the SA molecules to form additional cationic bridges-was found to moderately offset the efficiency of SA treatment.
本研究考察了海藻酸钠（SA）生物聚合物作为一种环境可持续试剂在稳定由高塑性黏土和轮胎衍生的磨碎橡胶（GR）制备的橡胶化土混合物方面的潜在用途。试验方案包括单轴压缩试验和扫描电子显微镜（SEM）试验；前者针对三种土 - GR混合物（GR与土的质量比分别为0%、5%和10%）进行，采用蒸馏水以及三种SA溶液（以SA与水的质量 - 体积比为5、10和15 g/L配制）作为压实液进行压实（并养护1、4、7和14天）。对于任何给定的GR含量，SA用量越大和/或养护时间越长，单轴抗压强度（UCS）越高，养护超过七天后增加的效益较小。这种行为归因于随着时间推移，相邻黏土表面之间所谓“阳离子桥”的形成和扩展（这是由于黏土和SA成分之间的“Ca/Mg⟷Na阳离子交换/取代”过程产生的），导致黏土颗粒絮凝。通过代表性的SEM图像进一步验证了这种黏土改良机制。最后，发现GR的添加（以及含量增加）——这意味着用GR颗粒部分替代土中的黏土含量，从而减少了SA分子形成额外阳离子桥的可用吸引位点数量——会适度抵消SA处理的效率。
