In the conventional packed drain method, a drain column is constructed in compressible soil by driving a casing to a designed depth, placing a cylindrical woven fabric pack or bag inside the casing, filling the pack with sand, and pulling out the casing. Four different types of non-woven and woven fabric packs were made and their performance during the construction was studied through a field test. As filling materials, sand, scrap tire, rock powder, bottom ash were used. Their applicability with respect to the different packs was investigated. An innovative method was introduced which was aimed to prevent the pack from being twisted inside the casing and, thus assure the soundness of drainage column. This method employs a specially designed guiding plate and an anti-twisting rod attached on the inner surface of the casing. The effectiveness of this method was evaluated as compared to that of the conventional packed drain method.
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