Evaluating sulfur-free lignin as a sustainable additive for soil improvement against frost resistance

JOURNAL OF CLEANER PRODUCTION

卷:251

Article

Liu, Yaowu¹  Zheng, Wenle¹  Wang, Qing¹  Cao, Chengjun¹  Chang, Mushi¹  Rocchi, Irene² 

[1] Jilin Univ, Coll Construct Engn, Changchun 130026, Peoples R China

[2] Tech Univ Denmark, Dept Civil Engn, Bldg 119, DK-2800 Lyngby, Denmark

关键词: Sulfur-free lignin;    Soil improvement;    Freeze-thaw cycles;    Sustainable geotechnical engineering;    Bioethanol waste elimination;   

DOI  :  10.1016/j.jclepro.2019.119504

来源: Elsevier

【 摘 要 】

This study investigates using Sulfur-Free Lignin (SFL) as a stabilizer to reinforce soil for civil engineering construction. To comprehensively evaluate the engineering performance of SFL stabilized soil, 3, 7, 10, 12 and 15% mixtures were tested and the influence of climate factors (assessed subjecting the soil to different freeze-thaw cycles) was also considered. The experimental program investigated mechanical strength (unconfined compressive strength) and physicochemical properties, which included grain size distribution, Atterberg limits, variation of elemental and mineral composition, pH, cation exchange capacity, X-ray diffraction/fluorescence and thermal conductivity. In addition, micro-characterization through SEM and pore size distribution was also performed. A considerable improvement of the mechanical properties was observed, which increases with SFL content up to 12%. This was based on changes in the physical and not chemical properties, hinting that the stabilization mechanism consists in physical binding unlike for traditional soil stabilizers. Moreover, it was found that SFL addition improved frost resistance. Based on these results, utilizing SFL as a soil stabilizer for application in earthworks shows great potential and would promote the bio-ethanol industry and engineering construction to be more sustainable and greener, particularly because it does not risk inducing soil pH contamination unlike traditional chemical agents. (C) 2019 Elsevier Ltd. All rights reserved.

【 授权许可】

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