ABSTRACT

The possibility of applying wood ash (WA), as a partial replacement of lime in subgrade stabilisation of clay soil of eastern Croatia, was explored in this study. The optimal ratios of lime substitution by WA were determined for the stabilisation of local clays of different plasticity. The results show that WA, a local available alternative material, can be used as a partial replacement of lime in the stabilisation of researched local clays for use in embankments and subgrades. The substitution of lime by WA resulted in similar changes in soil plasticity, granulometry and compaction properties. The optimal substitution ratio of lime with WA in the stabilised mixtures depends on the degree of plasticity of the base soil. The lowest optimal substitution ratio was recorded (25–50%) for high-plasticity soil. For medium- and low-plasticity soil, 50–75% of lime can be replaced by WA, resulting in the same or better California Bearing Ratio (CBR) values than the reference mixture. The CBR values for all mixtures were 18.82–107.34%. With the addition of all binder compositions, linear swelling was reduced to less than 1%. However, some aspects of chemical composition of WA can present limitations to WA use.

摘要

本研究探讨了在克罗地亚东部粘土路基稳定中应用木灰 (WA) 作为石灰部分替代物的可能性。确定了 WA 石灰替代的最佳比例，以稳定不同塑性的局部粘土。结果表明，WA，一种当地可用的替代材料，可用作石灰的部分替代物，用于稳定研究的当地粘土，用于路堤和路基。用 WA 代替石灰导致土壤可塑性、粒度和压实特性发生类似变化。稳定混合物中石灰与 WA 的最佳替代比取决于基土的可塑性程度。记录了高塑性土壤的最低最佳替代率（25-50%）。对于中低塑性土壤，50-75% 的石灰可以被 WA 替代，从而产生与参考混合物相同或更好的加利福尼亚轴承比 (CBR) 值。所有混合物的 CBR 值为 18.82–107.34%。随着所有粘合剂组合物的加入，线性溶胀降低到小于 1%。然而，WA 化学成分的某些方面可能会限制 WA 的使用。