Effect of Deep Remediation and Improvement on Bearing Capacity and Settlement of Piled Raft Foundation Subjected to Static and Cyclic Vertical Loading

ABSTRACT The effect of lime piles on the behavior of piled-raft foundation constructed on such soil and subjected to static and cyclic vertical loading was also investigated. The soil samples were contaminated artificially by light fuel oil (LFO) mixed with water and kerosene to simulate the contaminants that are usually disposed directly to the soil from the electricity power plant as a byproduct. The lime columns are holes of 20 mm diameter and 500 mm deep were drilled in the soil and filled with lime mixture. The lime mixture was prepared by mixing a dry soil with 15% of lime and natural water content and then poured into the holes and mixed thoroughly. The lime mixture was left for four weeks to allow the completion of most chemical reactions necessary for improvement and remediation of oil contaminated soil. Aluminum piles of 20 mm in diameter and 300 mm long were installed in soil models and subjected to static and cyclic vertical loading. Load-settlement curves showed that the contaminated soils have more settlement values compared with the intact soil, but improvement and remediation of soil samples showless settlement than that of contaminated samples. Lime piles are considered an efficient technique for decreasing the settlement of piled-raft foundations.