In this study, consolidation settlements of soft clay caused by cyclic loading and the affecting factors such as number of cycles and stress level were experimentally investigated. A group of samples prepared in slurry consolidometer in the laboratory were tested using cyclic simple shear testing device. Normally consolidated samples were subjected to five consecutive series of cyclic loading and drainage for 60 min were applied between each cyclic loading stages. Cyclic tests were performed with stress controlled two-way sinusoidal wave loading with different stress levels and number of cycles. Frequency of cyclic loading was constant as 0.1 Hz. As a result of this study, it can be concluded that soft clays subjected to undrained cyclic loading and drainage cycles exhibit more resistance against subsequent cyclic shear stresses. The consolidation settlements, pore pressures and shear strains decrease after each stage of cyclic loading. (c) 2006 Elsevier Ltd. All rights reserved.