Effects of GGBS and Fly Ash in Binders on Soil Stabilization for Road Construction

In this paper we propose a new technique of soil stabilization for road construction based on using new alternative binders. The project aims to evaluate the effects of alternative additive materials in soil stabilization contexts for road construction. The alternative binders (slag, energy ash and bio ash as new alternative road construction material) have been used to complement the traditional binders (cement and lime). The project used five binders and evaluated their effects on soil strength. The proposed method comprises advantages of using the alternative binders which are the residual products contributing to a lower environmental impact. The results have shown that only slag has significant effects on the strength of the stabilized soil, while bio ash and energy ash make a marginal contribution to the increase of strength. This is caused by the twofold reasons. First, the effects of the amount of ashes that should reach a certain threshold with respect to the total amount of binder that must be exceeded to have the effect of the soil mixture. Second, the bio fly ash was stored and it was not completely fresh which may have contributed to the carbonation during the storage period and results in a lower hardening ability. Based on the results of the study we recommend the use of bio fly ash as a supply material andfor its amount to be adjusted so the storage period is not too long. This study verified the effects of slag, cement and lime on stabilization of soil for road construction.