Abstract
This paper examines an importance of mechanical properties of lime stabilized soil with recycled bassanite (CaSO4·1/2H2O) derived from waste plasterboard. In order to clarify the influence of the new soil stabilizer on stabilization effect, four kinds of soil samples mixed with the stabilizer at different mixture rate were investigated by a series of laboratory tests (unconfined compression test, X-ray analysis and scanning electron microscope observation). The following conclusions were obtained from the present study: (1) Even if the stabilized soil is expanded by generating ettringite, the soil material gets to be strong gradually by increasing curing period. (2) The new lime stabilizer is suitable for better fine-grained soils than coarse-grained soils. However, even if coarse-grained soil, necessary strength can be secured by raising moderately the degree of compaction of the specimens. (3) Much ettringite (needle crystal, 3CaO·Al2O3·3CaSO4·32H2O) were generated in the lime stabilized soils, and those were locking soil particles.
