- 期刊
PERFORMANCE OF SAND DUNES IN STABILIZING HIGHLY EXPANSIVE SOIL
摘要
The expansive soil and sand dunes are abundant in desert areas at which new cities have been constructed. One of the effectively mitigation techniques for the expansive soil is to mix it with a non-swelling soil. This paper aims to study the influence of different sand dunes fractions, varying from zero to 50%, on the behaviour of the highly expansive clay. The clay-sand mixtures were also chemically stabilized by 10% of lime. The samples were remoulded according to the modified AASHTO compaction tests results. Swelling and strength tests were performed on each mixture. The results showed that mixing sand dunes with expansive clay reduced its swell potential and swelling pressure. The reductions increased as the increment of sand fraction. The swell potential and swelling pressure of the clay reduced to approximately the one-third when utilizing 50% sand. But mixing lime and sand with clay caused further significant reductions in swell properties. The swell potential and the swelling pressure of the clay were approximately suppressed when it was stabilized by 50% sand and 10% lime. Adding sands to clays had a negative effect on the strength. The CBR and UCS values of the clay-sand mixture decreased with increasing sand fractions. Once adding lime to the clay-sand mixtures, the CBR and UCS after 8-weeks curing time increased. The increments raised with increasing of sand fraction. The existence and the increment of sand dunes in clay influenced effectively on the chemical reactions with lime.