Mechanism of improvement in the strength and volume change behavior of lime stabilized soil

Use of quick and hydrated lime in stabilization of lateritic soil: comparative analysis of laboratory data

“…As with the results of the swell test, the changes in hydraulic conductivities are consistent with changes in the thickness of the adsorbed layer [11,18].…”

“…However, for the quicklime-treated specimens, the maximum swell value When lime is added to the soil, it causes (a) cation exchange and (b) flocculationagglomeration of clay particles. The combination of these two phenomena allows the small clay particles to floc together resulting in agglomerate of larger clay particles [18]. The net result is a substantial decrease in swelling characteristics of the soils.…”

“…As a result, there can be an immediate change in the workability of the material caused in the first instance by cation exchange which occurs when calcium ions released by the lime, exchange with metal ions within or on the clay structure. This cation exchange can increase the plastic limit (PL) and in turn reduce the PI [18,26]. With time, as the pozzolanic reactions begin to take effect, the plasticity changes further take place so that the plasticity index continues to decrease.…”

“…Overall, when lime is added to soil, reduction in swell potential occurs primarily because of alteration in clay structure [18,25,26]. Figure 13 shows the hydraulic conductivity values of the quick and hydrated lime stabilized lateritic soil.…”

“…In addition, pozzolanic reactions occur later between the calcium ions and the silica and alumina of the clay minerals. This results in the formation of cementitious products such as calcium-silicate-hydrates (C-S-H), calcium-aluminate-hydrates (C-A-H) and calcium-aluminum-silicate-hydrates (C-A-S-H) that are also responsible for the strength increase [1,7,13,18,27].…”