Strength behaviour of kaolin treated by demolished concrete materials

Abstract

Kaolin has claynite structure in nature, presenting several properties which may justify in many engineering and industrial applications. However, this type of soil is categorised as problematic soil because the presence of claynite properties eventually resulting the kaolin to have low shear strength and high compressibility as other clay soil. Due to that weakness, kaolinite does not meet the requirements necessary for any construction purposes particularly at the preliminary stage. Hence, to overcome this issue, soil stabilisation process is needed prior any construction works. The aim of this study is to determine the strength characteristics of stabilised soft clay soil (Kaolin S300) with demolished concrete materials (DCM). The selection of DCM as the stabilizer for the purpose reutilisation of waste materials that currently has been a great concern for the environmental sustainability. The percentages of DCM content used were 5%,10%,15%20%,25%,30% with varying curing time of 7days, 14 days and 28 days, respectively. Based on the result it was reported that, the unconfined compressive strength (UCS) test shows that the highest strength value obtained of 595.6 kPa kaolin treated with 30% DCM at 28 curing days. It is equivalent to 92% increment from the untreated kaolin sample at 0 days. However, the optimum amount of DCM which provides significant strength improvement was found when more than 20% of DCM is presented after 14 curing days. Hence, it shows the possible usage of DCM as waste material to effectively stabilize kaolin at specific amounts sufficiently.