Bulging as a pile imperfection

Piled foundation is a method of overcoming difficulties of founding on soft soils to ensure structural safety by transferring structural load through weak soil to a stiff stratum. Due to piles importance, it is becoming necessary to avoid pile defects. These defects arouse from inadequate ground investigations, construction phases, pile loading test, and natural unforeseen geological causes. In this paper bulging is studied as a pile imperfection. The effects of bulging width, length, and shape on the pile ultimate load are investigated. Bulging may increase pile ultimate load though it is still considered as a pile defect. It was found that bulging can increase the ultimate pile load up to 200%.