modeling and optimization of unconfined compressive strength of soil with simultaneous addition of gypsum and lime

N this research, it was tried to investigate the effect of gypsum and lime on the unconfined compressive strength of the soil. to achieve this goal, different amounts of gypsum, lime and kaolin were used. the experiment was designed using d-optimal method in design-expert 11 software. the results showed that the quadratic model is the appropriate model to fit to the available data. it has been found that this model can be used to predict the results. finally, with the help of numerical optimization, the optimal values for effective factors were determined. in practice, the result of these predictions was compared with the empirical result. it was found that the proposed model was able to provide a very good accurate prediction of the unconfined compressive strength obtainable from the soil according to the effective factors.