Improved Shear Strength Performance of Compacted Rubberized Clays Treated with Sodium Alginate Biopolymer

Polymers

卷:13

Ramin Raeesi¹  An Deng²  Abbas Taheri²  Mehdi Mirzababaei³  Amin Soltani⁴ 

[1] Department of Infrastructure Engineering, The University of Melbourne, Parkville, VIC 3010, Australia;

[2] School of Civil, Environmental and Mining Engineering, The University of Adelaide, Adelaide, SA 5005, Australia;

[3] School of Engineering and Technology, Central Queensland University, Melbourne, VIC 3000, Australia;

[4] School of Engineering, IT and Physical Sciences, Federation University, Churchill, VIC 3842, Australia;

关键词: clay soil;    ground rubber;    sodium alginate;    uniaxial compressive strength;    scanning electron microscopy;    curing duration;   

DOI  :  10.3390/polym13050764

来源: DOAJ

【 摘 要 】

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 “Ca²⁺/Mg²⁺ ⟷ 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.

【 授权许可】

Unknown