摘要：Ordinary co.umns of jet grouting are circular or fan-shaped. But in recent years, such shapes as candy-shaped co.umns were put to practical use. They are co.structed by switching the rotational speed of the stem in one rotation. We applied this method to swing jet grouting. That is, we changed the rotational speeds in the swing jet grouting to make elongated co.umns near rectangle. The test co.struction was succeeded and the co.umns’ shapes co.formed to those designed. In addition, the quality was co.firmed to be as good as ordinary co.umns. Radii （distances from center to outer ends） were 1.03 to 1.21 times as large as those designed. Improvement ratios were 95% or more in any position. Strengths were varied by location, but they satisfied design strength 1.5 kN/m2 at any position. We co.cluded that this new co.umn can be applied to practice in the same way as ordinary co.umns.