This paper deal with to investigation of the results of mineralogical and geotechnical studies on lime–stabilized soft clay soils in the southwest of Hamedan. In this order, the hydrated lime was added in the order of 1%, 3%, 5% and 7% by weight and laboratory experiments including mineralogical studies, grain size distribution, plasticity limits, compaction and uniaxial compressive strength were conducted on samples after 7, 15, 30 and 45 days of curing time. The test results indicate that increasing the lime percentage, the soil gradually loses it's plasticity characteristics and finally, it is non-plastic. In addition to, increasing the added lime and curing time, the compressive strength and elasticity modulus of the lime - treated soils increases. Based on the test results was determined that by addition of 7% lime and after 30 days curing time, the studied soft clay soil is stabilized as satisfactory. Therefore, the optimum lime content and proper curing time for limetreated soils is 7% and 30 days, respectively. Also, In order to investigation of relationship between lime-treated geotechnical properties with lime percentage and curing time, the multivariate regression analysis has been carried out that the results demonstrate high regression coefficients for the proposed relationships.
