LAUSR

This present study evaluates the efficacy of integrating grey relational analysis and super-efficiency models in Taguchi method to optimize multi-additives for expansive soil treatment. The additives, which were added by air-dried weight of the expansive soil, included sawdust ash (SDA), quarry dust (QD) and ordinary Portland cement (OPC). Unconfined compressive strength, California bearing ratio and differential free swell index were the responses determined in the study using the Taguchi designed experiment. Data obtained from the responses were further analyzed concurrently with a combination of grey relational analysis and super-efficiency models and the results obtained showed that the optimum combinations of additives that optimized the expansive soil simultaneously was found at 20% SDA, 20% QD and 8% OPC. Furthermore, the result of the confirmatory tests performed gave a clear indication that grey relational analysis and super-efficiency models can be combined and incorporated in Taguchi method to optimize multi-additives concurrently for expansive soil treatment.