Effects of aggregate size on water retention capacity and microstructure of lime-treated silty soil

Yejiao Wang (1) , Yu-Jun Cui (1) , Anh Minh A.M. Tang (2) , Chaosheng Tang (3) , Nadia Benahmed (4)

1 navier umr 8205 - Laboratoire Navier
2 cermes - Géotechnique
3 School of Earth Sciences and Engineering
4 UR OHAX - Ouvrages hydrauliques et hydrologie

Lime treatment is a common technique of improving the workability and geotechnical properties of soils. In this study, the aggregate size effects on the water retention capacity and microstructure of lime-treated soil were investigated. Two soil powders with different maximum aggregate sizes (D max = 0·4 and 5 mm) were prepared and stabilised by 2% lime (by weight of dry soil). Soil samples were prepared by compaction at dry side of optimum water content (w = 17%) with a dry density of 1·65 Mg/m 3. Suction and pore size distribution were determined after different curing periods. The results obtained show that: (a) the treated soil with smaller D max presents relatively smaller modal sizes and lower frequency of macropores (10–330 μm); (b) lime addition effectively improves the soil water retention capacity and decreases both the modal sizes of macro-and micropores gradually over time. Moreover, a higher air entry value and larger water retention capacity were also observed for a smaller D max value, in agreement with the pore size distributions.

Mots clés: laboratory tests; soil stabilisation; fabric/structure of soils

Domaines: Sciences de l'ingénieur [physics]; Génie civil; Géotechnique

Yejiao Wang, Yu-Jun Cui, Anh Minh A.M. Tang, Chaosheng Tang, Nadia Benahmed. Effects of aggregate size on water retention capacity and microstructure of lime-treated silty soil. Géotechnique Letters, 2015, 5 (4), pp.269-274. ⟨10.1680/jgele.15.00127⟩. ⟨hal-01271314⟩